query: 61% of colorectal cancer patients are diagnosed with regional or distant metastases.

title: Relation between Medicare screening reimbursement and stage at diagnosis for older patients with colon cancer.

text:
CONTEXT Medicare's reimbursement policy was changed in 1998 to provide coverage for screening colonoscopies for patients with increased colon cancer risk, and expanded further in 2001 to cover screening colonoscopies for all individuals.
 OBJECTIVE To determine whether the Medicare reimbursement policy changes were associated with an increase in either colonoscopy use or early stage colon cancer diagnosis.
 DESIGN, SETTING, AND PARTICIPANTS Patients in the Surveillance, Epidemiology, and End Results Medicare linked database who were 67 years of age and older and had a primary diagnosis of colon cancer during 1992-2002, as well as a group of Medicare beneficiaries who resided in Surveillance, Epidemiology, and End Results areas but who were not diagnosed with cancer.
 MAIN OUTCOME MEASURES Trends in colonoscopy and sigmoidoscopy use among Medicare beneficiaries without cancer were assessed using multivariate Poisson regression. Among the patients with cancer, stage was classified as early (stage I) vs all other (stages II-IV). Time was categorized as period 1 (no screening coverage, 1992-1997), period 2 (limited coverage, January 1998-June 2001), and period 3 (universal coverage, July 2001-December 2002). A multivariate logistic regression (outcome = early stage) was used to assess temporal trends in stage at diagnosis; an interaction term between tumor site and time was included.
 RESULTS Colonoscopy use increased from an average rate of 285/100,000 per quarter in period 1 to 889 and 1919/100,000 per quarter in periods 2 (P<.001) and 3 (P vs 2<.001), respectively. During the study period, 44,924 eligible patients were diagnosed with colorectal cancer. The proportion of patients diagnosed at an early stage increased from 22.5% in period 1 to 25.5% in period 2 and 26.3% in period 3 (P<.001 for each pairwise comparison). The changes in Medicare coverage were strongly associated with early stage at diagnosis for patients with proximal colon lesions (adjusted relative risk period 2 vs 1, 1.19; 95% confidence interval, 1.13-1.26; adjusted relative risk period 3 vs 2, 1.10; 95% confidence interval, 1.02-1.17) but weakly associated, if at all, for patients with distal colon lesions (adjusted relative risk period 2 vs 1, 1.07; 95% confidence interval, 1.01-1.13; adjusted relative risk period 3 vs 2, 0.97; 95% confidence interval, 0.90-1.05).
 CONCLUSIONS Expansion of Medicare reimbursement to cover colon cancer screening was associated with an increased use of colonoscopy for Medicare beneficiaries, and for those who were diagnosed with colon cancer, an increased probability of being diagnosed at an early stage. The selective effect of the coverage change on proximal colon lesions suggests that increased use of whole-colon screening modalities such as colonoscopy may have played a pivotal role.

title: Nationwide trends in incidence, treatment and survival of colorectal cancer patients with synchronous metastases

text: The aim of this study was to determine trends in incidence, treatment and survival of colorectal cancer (CRC) patients with synchronous metastases (Stage IV) in the Netherlands. This nationwide population-based study included 160,278 patients diagnosed with CRC between 1996 and 2011. We evaluated changes in stage distribution, location of synchronous metastases and treatment in four consecutive periods, using Chi square tests for trend. Median survival in months was determined, using Kaplan–Meier analysis. The proportion of Stage IV CRC patients (n = 33,421) increased from 19 % (1996–1999) to 23 % (2008–2011, p < 0.001). This was predominantly due to a major increase in the incidence of lung metastases (1.7–5.0 % of all CRC patients). During the study period, the primary tumor was resected less often in Stage IV patients (65–46 %) and the use of systemic treatment has increased (29–60 %). Also an increase in metastasectomy was found in patients with one metastatic site, especially in patients with liver-only disease (5–18 %, p < 0.001). Median survival of all Stage IV CRC patients increased from 7 to 12 months. Especially in patients with metastases confined to the liver or lungs this improvement in survival was apparent (9–16 and 12–24 months respectively, both p < 0.001). In the last two decades, more lung metastases were detected and an increasing proportion of Stage IV CRC patients was treated with systemic therapy and/or metastasectomy. Survival of patients has significantly improved. However, the prognosis of Stage IV patients becomes increasingly diverse.

title: Social and geographical factors affecting access to treatment of colorectal cancer: a cancer registry study

text:
OBJECTIVE Cancer outcomes vary between and within countries with patients from deprived backgrounds known to have inferior survival. The authors set out to explore the effect of deprivation in relation to the accessibility of hospitals offering diagnostic and therapeutic services on stage at presentation and receipt of treatment.
 DESIGN Analysis of a Cancer Registry Database. Data included stage and treatment details from the first 6 months. The socioeconomic status of the immediate area of residence and the travel time from home to hospital was derived from the postcode.
 SETTING Population-based study of patients resident in a large area in the north of England.
 PARTICIPANTS 39 619 patients with colorectal cancer diagnosed between 1994 and 2002.
 OUTCOMES MEASURED Stage of diagnosis and receipt of treatment in relation to deprivation and distance from hospital.
 RESULTS Patients in the most deprived quartile were significantly more likely to be diagnosed at stage 4 for rectal cancer (OR 1.516, p<0.05) but less so for colonic cancer. There was a trend for both sites for patients in the most deprived quartile to be less likely to receive chemotherapy for stage 4 disease. Patients with colonic cancer were very significantly less likely to receive any treatment if they came from any but the most affluent area (ORs 0.639, 0.603 and 0.544 in increasingly deprived quartiles), this may have been exacerbated if the hospital was distant from their residence (OR for forth quartile for both travel and deprivation 0.731, not significant). The effect was less for rectal cancer and no effect of distance was seen.
 CONCLUSIONS Residing in a deprived area is associated with tendencies to higher stage at diagnosis and especially in the case of colonic cancer to reduced receipt of treatment. These observations are consistent with other findings and indicate that access to diagnosis requires further investigation.

title: Malignancies, prothrombotic mutations, and the risk of venous thrombosis.

text:
CONTEXT Venous thrombosis is a common complication in patients with cancer, leading to additional morbidity and compromising quality of life.
 OBJECTIVE To identify individuals with cancer with an increased thrombotic risk, evaluating different tumor sites, the presence of distant metastases, and carrier status of prothrombotic mutations.
 DESIGN, SETTING, AND PATIENTS A large population-based, case-control (Multiple Environmental and Genetic Assessment [MEGA] of risk factors for venous thrombosis) study of 3220 consecutive patients aged 18 to 70 years, with a first deep venous thrombosis of the leg or pulmonary embolism, between March 1, 1999, and May 31, 2002, at 6 anticoagulation clinics in the Netherlands, and separate 2131 control participants (partners of the patients) reported via a questionnaire on acquired risk factors for venous thrombosis. Three months after discontinuation of the anticoagulant therapy, all patients and controls were interviewed, a blood sample was taken, and DNA was isolated to ascertain the factor V Leiden and prothrombin 20210A mutations.
 MAIN OUTCOME MEASURE Risk of venous thrombosis.
 RESULTS The overall risk of venous thrombosis was increased 7-fold in patients with a malignancy (odds ratio [OR], 6.7; 95% confidence interval [CI], 5.2-8.6) vs persons without malignancy. Patients with hematological malignancies had the highest risk of venous thrombosis, adjusted for age and sex (adjusted OR, 28.0; 95% CI, 4.0-199.7), followed by lung cancer and gastrointestinal cancer. The risk of venous thrombosis was highest in the first few months after the diagnosis of malignancy (adjusted OR, 53.5; 95% CI, 8.6-334.3). Patients with cancer with distant metastases had a higher risk vs patients without distant metastases (adjusted OR, 19.8; 95% CI, 2.6-149.1). Carriers of the factor V Leiden mutation who also had cancer had a 12-fold increased risk vs individuals without cancer and factor V Leiden (adjusted OR, 12.1; 95% CI, 1.6-88.1). Similar results were indirectly calculated for the prothrombin 20210A mutation in patients with cancer.
 CONCLUSIONS Patients with cancer have a highly increased risk of venous thrombosis especially in the first few months after diagnosis and in the presence of distant metastases. Carriers of the factor V Leiden and prothrombin 20210A mutations appear to have an even higher risk.

title: Hypoxia in relation to vasculature and proliferation in liver metastases in patients with colorectal cancer.

text:
PURPOSE To investigate hypoxia measured by pimonidazole binding, glucose transporter 1 (GLUT1) and carbonic anhydrase IX (CA-IX) expression, proliferation, and vascularity in liver metastases of colorectal cancer and to compare GLUT1 and CA-IX expression in corresponding primary tumors.
 METHODS AND MATERIALS Twenty-five patients with liver metastases of colorectal cancer, planned for metastasectomy, were included. The hypoxia marker pimonidazole and proliferation marker iododeoxyuridine were administered before surgery. After immunofluorescent staining of the frozen metastases, pimonidazole binding, vascularity, and proliferation were analyzed quantitatively. Thirteen paraffin-embedded primary tumors were stained immunohistochemically for GLUT1 and CA-IX expression, which was analyzed semiquantitatively in primary tumors and corresponding liver metastases.
 RESULTS In liver metastases, pimonidazole binding showed a pattern consistent with diffusion-limited hypoxia. The mean pimonidazole-positive fraction was 0.146; the mean distance from vessels to pimonidazole-positive areas was 80 microm. When expressed, often co-localization was observed between pimonidazole binding and GLUT1 or CA-IX expression, but microregional areas of mismatch were also observed. No correlation between the level of pimonidazole binding and GLUT1 or CA-IX expression was observed. In some patients, a large fraction (up to 30%) of proliferating cells was present in pimonidazole-stained areas. Expression of CA-IX in primary tumors and metastases showed a significant correlation, which was absent for GLUT1 expression.
 CONCLUSIONS Compared with other tumor types, liver metastases of colorectal cancer contain large amounts of hypoxic cells. The lack of correlation with pimonidazole binding brings into question the value of GLUT1 and CA-IX as endogenous markers of hypoxia.

title: Elevated expression of miR-24-3p is a potentially adverse prognostic factor in colorectal adenocarcinoma.

text:
OBJECTIVES Several miRNAs are aberrantly expressed in cancer. miR-24-3p is involved in cancer-related cellular processes, including cell cycle control, cell growth, proliferation, and apoptosis. In this study, we examined the potential diagnostic and prognostic significance of miR-24-3p expression in colorectal adenocarcinoma.
 DESIGN AND METHODS Total RNA was isolated from 182 colorectal adenocarcinoma specimens and 86 paired non-cancerous colorectal mucosae. After polyadenylation of 2μg total RNA and reverse transcription into first-strand cDNA using an oligo-dT-adapter primer, miR-24-3p expression was quantified using an in-house-developed reverse-transcription real-time quantitative PCR method, based on the SYBR Green chemistry. SNORD43 (RNU43) was used as a reference gene.
 RESULTS miR-24-3p levels do not significantly differ between colorectal adenocarcinoma and non-cancerous colorectal mucosae. Thus, miR-24-3p expression cannot be used for diagnostic purposes. However, high miR-24-3p expression predicts poor disease-free survival (DFS) and overall survival (OS) of colorectal adenocarcinoma patients. Multivariate Cox regression analysis confirmed that miR-24-3p overexpression is a significant predictor of relapse in colorectal adenocarcinoma and that its prognostic significance is independent of other established prognostic factors and treatment of patients. Of note, miR-24-3p overexpression retains its rather unfavorable prognostic value in the subgroup of patients with advanced yet locally restricted colorectal adenocarcinoma (T3) and in those without distant metastasis (M0). Moreover, miR-24-3p overexpression is a potentially unfavorable prognosticator for patients who were not treated with radiotherapy.
 CONCLUSIONS Strong expression of miR-24-3p predicts poor DFS and OS of colorectal adenocarcinoma patients, independently of clinicopathological parameters that are currently used for prognosis in this human malignancy.

title: Global cancer statistics 2018: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries.

text: This article provides a status report on the global burden of cancer worldwide using the GLOBOCAN 2018 estimates of cancer incidence and mortality produced by the International Agency for Research on Cancer, with a focus on geographic variability across 20 world regions. There will be an estimated 18.1 million new cancer cases (17.0 million excluding nonmelanoma skin cancer) and 9.6 million cancer deaths (9.5 million excluding nonmelanoma skin cancer) in 2018. In both sexes combined, lung cancer is the most commonly diagnosed cancer (11.6% of the total cases) and the leading cause of cancer death (18.4% of the total cancer deaths), closely followed by female breast cancer (11.6%), prostate cancer (7.1%), and colorectal cancer (6.1%) for incidence and colorectal cancer (9.2%), stomach cancer (8.2%), and liver cancer (8.2%) for mortality. Lung cancer is the most frequent cancer and the leading cause of cancer death among males, followed by prostate and colorectal cancer (for incidence) and liver and stomach cancer (for mortality). Among females, breast cancer is the most commonly diagnosed cancer and the leading cause of cancer death, followed by colorectal and lung cancer (for incidence), and vice versa (for mortality); cervical cancer ranks fourth for both incidence and mortality. The most frequently diagnosed cancer and the leading cause of cancer death, however, substantially vary across countries and within each country depending on the degree of economic development and associated social and life style factors. It is noteworthy that high-quality cancer registry data, the basis for planning and implementing evidence-based cancer control programs, are not available in most low- and middle-income countries. The Global Initiative for Cancer Registry Development is an international partnership that supports better estimation, as well as the collection and use of local data, to prioritize and evaluate national cancer control efforts. CA: A Cancer Journal for Clinicians 2018;0:1-31. © 2018 American Cancer Society.

title: Identification of bone and liver metastases from breast cancer by measurement of plasma alkaline phosphatase isoenzyme activity.

text: Plasma alkaline phosphatase isoenzyme activities were determined in patients with breast cancer to diagnose and monitor bone and liver metastases. Bone alkaline phosphatase activity was increased in 21 of 50 patients (42%) with radiologically confirmed bone metastases, while total alkaline phosphatase activity was increased in only 10 of 50 (20%); liver alkaline phosphatase activity was raised in 12 of 25 patients (48%) with liver metastases. All patients with liver metastases had bone metastases. Bone alkaline phosphatase activity was significantly higher in patients with symptomatic bone disease. Isoenzyme determination provided additional information that would have changed patient management in five of 20 patients who were monitored serially. Measurement of alkaline phosphatase isoenzyme activity, though less sensitive than imaging procedures, can assist in screening for, and in early detection of, a high proportion of bone and liver metastases, and can provide useful objective evidence of their response to treatment.

title: Operable non-small cell lung cancer diagnosed by transpleural techniques : do they affect relapse and prognosis?

text:
STUDY OBJECTIVE We assessed whether transpleural methods for diagnosing peripheral lung cancer, such as needle aspiration or tumor excision, affect relapse and prognosis, because these techniques have potential to spread malignant cells from the tumor.
 DESIGN A retrospective study.
 SETTING National referral hospital.
 PATIENTS We reviewed 239 patients who underwent surgery between 1990 and 1998 and for whom non-small cell lung cancer (NSCLC) of < 3 cm in maximum diameter was completely resected. The duration of postoperative follow-up ranged from 12 to 105 months, with a median period of 45 months.
 INTERVENTIONS We defined the transbronchial method as using a bronchoscope, and the transpleural method as using needle aspiration cytology or tumor excision. Dichotomous variables included gender, histologic type of squamous cell carcinoma or other type of carcinoma, pathologic stage, and whether the diagnostic method was the transbronchial type only (first-line method) or the transpleural type (second-line method).
 RESULTS NSCLC was diagnosed in 45 patients by the transpleural technique and in 194 patients by the transbronchial technique. There were no significant statistical differences in age of patients, gender, histologic type, pathologic stage, and tumor size. There were 42 relapses, 7 in the transpleural technique group and 35 in the transbronchial technique group (p = 0.90). Of the 7 patients in the transpleural group, there were 4 distant metastasis and 3 local relapses; of the 35 patients in the transbronchial group, there were 20 distant metastasis and 15 local relapses (p = 0.99). Pleural carcinomatosis occurred in none of the 45 patients in the transpleural group and in 1 case (0.5%) in the 194 patients in the transbronchial group (p = 0.99). Patients in the transpleural group had a statistically better 5-year survival rate than patients in the transbronchial group (79.4% vs 60.3%, p = 0.04). This is also confirmed as an independent prognostic factor in a multivariate analysis.
 CONCLUSIONS Transpleural methods seem to be an advisable way to diagnose operable lung cancer that is difficult to diagnose using bronchoscopy, because these methods did not affect relapse and prognosis in the patients in our study.

title: Colorectal cancer survival in socioeconomic groups in England: variation is mainly in the short term after diagnosis.

text:
UNLABELLED The objective of this study was to examine differences in cancer survival between socioeconomic groups in England, with particular attention to survival in the short term of follow-up.
 PATIENTS AND METHODS Individuals diagnosed with colorectal cancer between 1996 and 2004 in England were identified from cancer registry records. Five-year cumulative relative survival and excess death rates were computed.
 RESULTS For colon cancer there was a very high excess death rate in the first month of follow-up, and the excess death rate was highest in the socioeconomically deprived groups. In subsequent periods, excess mortality rates were much lower and there was less socioeconomic variation. The pattern of variation in excess death rates was generally similar in rectal cancer but the socioeconomic difference in death rates persisted several years longer. If the excess death rates in the entire colorectal cancer patient population were the same as those observed in the most affluent socioeconomic quintile, the annual reduction would be 360 deaths in colon cancer and 336 deaths in rectal cancer patients. These deaths occurred almost entirely in the first month and the first year after diagnosis.
 CONCLUSION Recent developments in the national cancer control agenda have included an increasing emphasis on outcome measures, with short-term cancer survival an operational measure of variation and progress in cancer control. In providing clues to the nature of the survival differences between socioeconomic groups, the results presented here give strong support for this strategy.

title: Pancreatic stellate cells: partners in crime with pancreatic cancer cells.

text: Pancreatic stellate cells (PSC) produce the stromal reaction in pancreatic cancer, but their role in cancer progression is not fully elucidated. We examined the influence of PSCs on pancreatic cancer growth using (a) an orthotopic model of pancreatic cancer and (b) cultured human PSCs (hPSC) and human pancreatic cancer cell lines MiaPaCa-2 and Panc-1. Athymic mice received an intrapancreatic injection of saline, hPSCs, MiaPaCa-2 cells, or hPSCs + MiaPaCa-2. After 7 weeks, tumor size, metastases, and tumor histology were assessed. In vitro studies assessed the effect of cancer cell secretions on PSC migration and the effect of hPSC secretions on cancer cell proliferation, apoptosis, and migration. Possible mediators of the effects of hPSC secretions on cancer cell proliferation were examined using neutralizing antibodies. Compared with mice receiving MiaPaCa-2 cells alone, mice injected with hPSCs + MiaPaCa-2 exhibited (a) increased tumor size and regional and distant metastasis, (b) fibrotic bands (desmoplasia) containing activated PSCs within tumors, and (c) increased tumor cell numbers. In vitro studies showed that, in the presence of pancreatic cancer cells, PSC migration was significantly increased. Furthermore, hPSC secretions induced the proliferation and migration, but inhibited the apoptosis, of MiaPaCa-2 and Panc-1 cells. The proliferative effect of hPSC secretions on pancreatic cancer cells was inhibited in the presence of neutralizing antibody to platelet-derived growth factor. Our studies indicate a significant interaction between pancreatic cancer cells and stromal cells (PSCs) and imply that pancreatic cancer cells recruit stromal cells to establish an environment that promotes cancer progression.

title: Metastatic colonization requires the repression of the epithelial-mesenchymal transition inducer Prrx1.

text: The epithelial-mesenchymal transition (EMT) is required in the embryo for the formation of tissues for which cells originate far from their final destination. Carcinoma cells hijack this program for tumor dissemination. The relevance of the EMT in cancer is still debated because it is unclear how these migratory cells colonize distant tissues to form macrometastases. We show that the homeobox factor Prrx1 is an EMT inducer conferring migratory and invasive properties. The loss of Prrx1 is required for cancer cells to metastasize in vivo, which revert to the epithelial phenotype concomitant with the acquisition of stem cell properties. Thus, unlike the classical EMT transcription factors, Prrx1 uncouples EMT and stemness, and is a biomarker associated with patient survival and lack of metastasis.

title: Chemotherapy options in elderly and frail patients with metastatic colorectal cancer (MRC FOCUS2): an open-label, randomised factorial trial

text:
BACKGROUND Elderly and frail patients with cancer, although often treated with chemotherapy, are under-represented in clinical trials. We designed FOCUS2 to investigate reduced-dose chemotherapy options and to seek objective predictors of outcome in frail patients with advanced colorectal cancer.
 METHODS We undertook an open, 2 × 2 factorial trial in 61 UK centres for patients with previously untreated advanced colorectal cancer who were considered unfit for full-dose chemotherapy. After comprehensive health assessment (CHA), patients were randomly assigned by minimisation to: 48-h intravenous fluorouracil with levofolinate (group A); oxaliplatin and fluorouracil (group B); capecitabine (group C); or oxaliplatin and capecitabine (group D). Treatment allocation was not masked. Starting doses were 80% of standard doses, with discretionary escalation to full dose after 6 weeks. The two primary outcome measures were: addition of oxaliplatin ([A vs B] + [C vs D]), assessed with progression-free survival (PFS); and substitution of fluorouracil with capecitabine ([A vs C] + [B vs D]), assessed by change from baseline to 12 weeks in global quality of life (QoL). Analysis was by intention to treat. Baseline clinical and CHA data were modelled against outcomes with a novel composite measure, overall treatment utility (OTU). This study is registered, number ISRCTN21221452.
 FINDINGS 459 patients were randomly assigned (115 to each of groups A-C, 114 to group D). Factorial comparison of addition of oxaliplatin versus no addition suggested some improvement in PFS, but the finding was not significant (median 5·8 months [IQR 3·3-7·5] vs 4·5 months [2·8-6·4]; hazard ratio 0·84, 95% CI 0·69-1·01, p=0·07). Replacement of fluorouracil with capecitabine did not improve global QoL: 69 of 124 (56%) patients receiving fluorouracil reported improvement in global QoL compared with 69 of 123 (56%) receiving capecitabine. The risk of having any grade 3 or worse toxic effect was not significantly increased with oxaliplatin (83/219 [38%] vs 70/221 [32%]; p=0·17), but was higher with capecitabine than with fluorouracil (88/222 [40%] vs 65/218 [30%]; p=0·03). In multivariable analysis, fewer baseline symptoms (odds ratio 1·32, 95% CI 1·14-1·52), less widespread disease (1·51, 1·05-2·19), and use of oxaliplatin (0·57, 0·39-0·82) were predictive of better OTU.
 INTERPRETATION FOCUS2 shows that with an appropriate design, including reduced starting doses of chemotherapy, frail and elderly patients can participate in a randomised controlled trial. On balance, a combination including oxaliplatin was preferable to single-agent fluoropyrimidines, although the primary endpoint of PFS was not met. Capecitabine did not improve QoL compared with fluorouracil. Comprehensive baseline assessment holds promise as an objective predictor of treatment benefit.
 FUNDING Cancer Research UK and the Medical Research Council.

title: Systematic review of role of bisphosphonates on skeletal morbidity in metastatic cancer.

text:
OBJECTIVE To review the evidence for the use of bisphosphonates to reduce skeletal morbidity in cancer patients with bone metastases.
 DATA SOURCES Electronic databases, scanning reference lists, and consultation with experts and pharmaceutical companies. Foreign language papers were included.    STUDY SELECTION Included trials were randomised controlled trials of patients with malignant disease and bone metastases who were treated with oral or intravenous bisphosphonate compared with another bisphosphonate, placebo, or standard care. All trials measured at least one outcome of skeletal morbidity.
 RESULTS 95 articles were identified; 30 studies fulfilled inclusion criteria. In studies that lasted > or = 6 months, compared with placebo bisphosphonates significantly reduced the odds ratio for fractures (vertebral 0.69, 95% confidence interval 0.57 to 0.84, P < 0.0001; non-vertebral 0.65, 0.54 to 0.79, P < 0.0001; combined 0.65, 0.55 to 0.78, P < 0.0001), radiotherapy (0.67, 0.57 to 0.79, P < 0.0001), and hypercalcaemia (0.54, 0.36 to 0.81, P = 0.003) but not for orthopaedic surgery (0.70, 0.46 to 1.05, P = 0.086) or spinal cord compression (0.71, 0.47 to 1.08, P = 0.113). The reduction in orthopaedic surgery was significant in studies that lasted over a year (0.59, 0.39 to 0.88, P = 0.009). Use of bisphosphonates significantly increased time to first skeletal related event but did not increase survival. Subanalyses showed that most evidence supports use of intravenous aminobisphosphonates.
 CONCLUSIONS In people with metastatic bone disease bisphosphonates significantly decrease skeletal morbidity, except for spinal cord compression and increased time to first skeletal related event. Treatment should start when bone metastases are diagnosed and continue until it is no longer clinically relevant.

title: Lysyl oxidase is essential for hypoxia-induced metastasis

text: Metastasis is a multistep process responsible for most cancer deaths, and it can be influenced by both the immediate microenvironment (cell–cell or cell–matrix interactions) and the extended tumour microenvironment (for example vascularization). Hypoxia (low oxygen) is clinically associated with metastasis and poor patient outcome, although the underlying processes remain unclear. Microarray studies have shown the expression of lysyl oxidase (LOX) to be elevated in hypoxic human tumour cells. Paradoxically, LOX expression is associated with both tumour suppression and tumour progression, and its role in tumorigenesis seems dependent on cellular location, cell type and transformation status. Here we show that LOX expression is regulated by hypoxia-inducible factor (HIF) and is associated with hypoxia in human breast and head and neck tumours. Patients with high LOX-expressing tumours have poor distant metastasis-free and overall survivals. Inhibition of LOX eliminates metastasis in mice with orthotopically grown breast cancer tumours. Mechanistically, secreted LOX is responsible for the invasive properties of hypoxic human cancer cells through focal adhesion kinase activity and cell to matrix adhesion. Furthermore, LOX may be required to create a niche permissive for metastatic growth. Our findings indicate that LOX is essential for hypoxia-induced metastasis and is a good therapeutic target for preventing and treating metastases.

title: Geographical access to healthcare in Northern England and post-mortem diagnosis of cancer.

text:
BACKGROUND There is some previous evidence that diagnosis of cancer at death, recorded as registry death certificate only records, is associated with problems of access to care.
 METHODS Records from the Northern and Yorkshire Cancer Registry for patients registered with breast, colorectal, lung, ovarian or prostate cancer between 1994 and 2002 were supplemented with measures of travel time to general practitioner and hospital services, and social deprivation. Logistic regression was used to identify predictors of records where diagnosis was at death.
 RESULTS There was no association between the odds diagnosis at death and access to primary care. For all sites except breast, the highest odds of being a cancer diagnosed at death fell among those living in the highest quartile of hospital travel time, although it was only statistically significant for colorectal and ovary tumours. Those in the most deprived and furthest travel time to hospital quartile were 2.6 times more likely to be a diagnosis at death case compared with those in the most affluent and proximal areas.
 CONCLUSIONS There is some evidence that poorer geographical access to tertiary care, in particular when coupled with social disadvantages, may be associated with increased odds of diagnosis at death.

title: Plasma vitamin D metabolites and risk of colorectal cancer in women.

text:
OBJECTIVE Experimental evidence suggests that 1,25-dihydroxyvitamin D and its precursor, 25-hydroxyvitamin D [25(OH)D], may aid in the prevention of colorectal cancer. We therefore examined risk in relation to plasma concentrations of these vitamin D metabolites.
 METHODS In a nested case-control study among women in the Nurses' Health Study, we identified 193 colorectal cancer cases, ages 46 to 78 years, diagnosed up to 11 years after blood collection. Two controls were matched per case on year of birth and month of blood draw. Odds ratios (OR) for risk of colorectal cancer were calculated using conditional logistic regression adjusted for body mass index, physical activity, smoking, family history, use of hormone replacement therapy, aspirin use, and dietary intakes.
 RESULTS We found a significant inverse linear association between plasma 25(OH)D and risk of colorectal cancer (P = 0.02). Among women in the highest quintile, the OR (95% confidence interval) was 0.53 (0.27-1.04). This inverse association remained strong when limited to women > or =60 years at blood collection (P = 0.006) but was not apparent among the younger women (P = 0.70). Benefit from higher 25(OH)D concentrations was observed for cancers at the distal colon and rectum (P = 0.02) but was not evident for those at the proximal colon (P = 0.81). In contrast to 25(OH)D, we did not observe an association between 1,25-dihydroxyvitamin D and colorectal cancer, although risk was elevated among the women in the highest quintile if they were also in the lower half of the 25(OH)D distribution (OR, 2.52; 95% confidence interval, 1.04-6.11).
 CONCLUSION From these results and supporting evidence from previous studies, we conclude that higher plasma levels of 25(OH)D are associated with a lower risk of colorectal cancer in older women, particularly for cancers at the distal colon and rectum.

title: Role of the vascular endothelial growth factor pathway in tumor growth and angiogenesis.

text: New blood vessel formation (angiogenesis) is a fundamental event in the process of tumor growth and metastatic dissemination. Hence, the molecular basis of tumor angiogenesis has been of keen interest in the field of cancer research. The vascular endothelial growth factor (VEGF) pathway is well established as one of the key regulators of this process. The VEGF/VEGF-receptor axis is composed of multiple ligands and receptors with overlapping and distinct ligand-receptor binding specificities, cell-type expression, and function. Activation of the VEGF-receptor pathway triggers a network of signaling processes that promote endothelial cell growth, migration, and survival from pre-existing vasculature. In addition, VEGF mediates vessel permeability, and has been associated with malignant effusions. More recently, an important role for VEGF has emerged in mobilization of endothelial progenitor cells from the bone marrow to distant sites of neovascularization. The well-established role of VEGF in promoting tumor angiogenesis and the pathogenesis of human cancers has led to the rational design and development of agents that selectively target this pathway. Studies with various anti-VEGF/VEGF-receptor therapies have shown that these agents can potently inhibit angiogenesis and tumor growth in preclinical models. Recently, an anti-VEGF antibody (bevacizumab), when used in combination with chemotherapy, was shown to significantly improve survival and response rates in patients with metastatic colorectal cancer and thus, validate VEGF pathway inhibitors as an important new treatment modality in cancer therapy.

title: Loss of imprinting in colorectal cancer linked to hypomethylation of H19 and IGF2.

text: Epigenetic alterations in human cancers include global DNA hypomethylation,gene hypomethylation and promoter hypermethylation, and loss of imprinting (LOI) of the insulin-like growth factor-II gene (IGF2). A mechanism for LOI described previously is hypermethylation of a differentially methylated region (DMR) upstream of the H19 gene, allowing activation of the normally silent maternal allele of IGF2. Here we show that this mechanism does not apply to colorectal cancers, which show hypomethylation of the H19 DMR as well as a DMR upstream of exon 3 of IGF2. This hypomethylation is found in both colorectal cancers and normal mucosa from the same patients, and in cell lines with somatic cell knockout of DNA methyltransferases DNMT1 and DNMT3B. These data suggest that hypomethylation is a mechanism for LOI, that the popular IGF2-H19 enhancer competition model for IGF2 imprinting does not apply to the human colon, and that an alternative model for LOI would involve a transcriptional repressor acting on the normally silent maternal allele of IGF2.

title: Cancer survival increases in Europe, but international differences remain wide.

text: The EUROCARE project analysed cancer survival data from 45 population-based cancer registries in 17 European countries, revealing wide international differences in cancer survival. We calculated 5-year relative survival for 1836287 patients diagnosed with one of 13 cancers during the period 1978-1989. The data, from 20 cancer registries in 13 countries, were grouped into four regions: Finland, Sweden, Iceland (Northern Europe); Denmark, England and Scotland (UK and Denmark); France, The Netherlands, Germany, Italy and Switzerland (Western Europe); Estonia and Poland (Eastern Europe), and broken down into four periods (1978-1980, 1981-1983, 1984-1986, 1987-1989). For each cancer, mean European and regional survival was estimated as the weighted mean of 5-year relative survival in each country. Survival increased with time for all tumours, particularly for cancers of testis (12% increase, i.e. from 79.9 to 91.9%), breast, large bowel, skin melanoma (approximately 9-10%), and lymphomas (approximately 7%). For most solid tumours, survival was highest in Northern Europe and lowest in Eastern Europe, and also low in the UK and Denmark. Regional variation was less marked for the lymphomas. Survival improved more in Western than Northern Europe, and the differences between these regions fell for bowel cancer (from 8.0% for those diagnosed in 1978-1980 to 2% for those diagnosed in 1987-1989), breast cancer (from 7.4% to 3.9%), skin melanoma (from 13.4% to 11.0%) and Hodgkin's disease (from 7.2 to 0.6%). For potentially curable malignancies such as Hodgkin's disease, large bowel, breast and testicular cancers, there were substantial increases in survival, suggesting an earlier diagnosis and more effective treatment. The persisting regional differences suggest there are corresponding differences in the availability of diagnostic and therapeutic facilities, and in the effectiveness of healthcare systems.


query: 7-day-old adult Caenorhabditis elegans exhibit approximately 5% of the learning capacity seen in 1-day old adults.

title: Insulin Signaling and Dietary Restriction Differentially Influence the Decline of Learning and Memory with Age

text: Of all the age-related declines, memory loss is one of the most devastating. While conditions that increase longevity have been identified, the effects of these longevity-promoting factors on learning and memory are unknown. Here we show that the C. elegans Insulin/IGF-1 receptor mutant daf-2 improves memory performance early in adulthood and maintains learning ability better with age but, surprisingly, demonstrates no extension in long-term memory with age. By contrast, eat-2 mutants, a model of Dietary Restriction (DR), exhibit impaired long-term memory in young adulthood but maintain this level of memory longer with age. We find that crh-1, the C. elegans homolog of the CREB transcription factor, is required for long-term associative memory, but not for learning or short-term memory. The expression of crh-1 declines with age and differs in the longevity mutants, and CREB expression and activity correlate with memory performance. Our results suggest that specific longevity treatments have acute and long-term effects on cognitive functions that decline with age through their regulation of rate-limiting genes required for learning and memory.

title: Age of ovary determines remaining life expectancy in old ovariectomized mice.

text: We investigated the capacity of young ovaries, transplanted into old ovariectomized CBA mice, to improve remaining life expectancy of the hosts. Donor females were sexually mature 2-month-olds; recipients were prepubertally ovariectomized at 3 weeks and received transplants at 5, 8 or 11 months of age. Relative to ovariectomized control females, life expectancy at 11 months was increased by 60% in 11-month recipient females and by 40% relative to intact control females. Only 20% of the 11-month transplant females died in the 300-day period following ovarian transplantation, whereas nearly 65% of the ovariectomized control females died during this same period. The 11-month-old recipient females resumed oestrus and continued to cycle up to several months beyond the age of control female reproductive senescence. Across the three recipient age groups, transplantation of young ovaries increased life expectancy in proportion to the relative youth of the ovary. Our results relate to recent findings on the gonadal input upon aging in Caenorhabditis elegans and may suggest how the mammalian gonad, including that of humans, could regulate aging and determine longevity.

title: Neurite sprouting and synapse deterioration in the aging Caenorhabditis elegans nervous system.

text: Caenorhabditis elegans is a powerful model for analysis of the conserved mechanisms that modulate healthy aging. In the aging nematode nervous system, neuronal death and/or detectable loss of processes are not readily apparent, but because dendrite restructuring and loss of synaptic integrity are hypothesized to contribute to human brain decline and dysfunction, we combined fluorescence microscopy and electron microscopy (EM) to screen at high resolution for nervous system changes. We report two major components of morphological change in the aging C. elegans nervous system: (1) accumulation of novel outgrowths from specific neurons, and (2) physical decline in synaptic integrity. Novel outgrowth phenotypes, including branching from the main dendrite or new growth from somata, appear at a high frequency in some aging neurons, but not all. Mitochondria are often associated with age-associated branch sites. Lowered insulin signaling confers some maintenance of ALM and PLM neuron structural integrity into old age, and both DAF-16/FOXO and heat shock factor transcription factor HSF-1 exert neuroprotective functions. hsf-1 can act cell autonomously in this capacity. EM evaluation in synapse-rich regions reveals a striking decline in synaptic vesicle numbers and a diminution of presynaptic density size. Interestingly, old animals that maintain locomotory prowess exhibit less synaptic decline than same-age decrepit animals, suggesting that synaptic integrity correlates with locomotory healthspan. Our data reveal similarities between the aging C. elegans nervous system and mammalian brain, suggesting conserved neuronal responses to age. Dissection of neuronal aging mechanisms in C. elegans may thus influence the development of brain healthspan-extending therapies.

title: The threshold for polyglutamine-expansion protein aggregation and cellular toxicity is dynamic and influenced by aging in Caenorhabditis elegans.

text: Studies of the mutant gene in Huntington's disease, and for eight related neurodegenerative disorders, have identified polyglutamine (polyQ) expansions as a basis for cellular toxicity. This finding has led to a disease hypothesis that protein aggregation and cellular dysfunction can occur at a threshold of approximately 40 glutamine residues. Here, we test this hypothesis by expression of fluorescently tagged polyQ proteins (Q29, Q33, Q35, Q40, and Q44) in the body wall muscle cells of Caenorhabditis elegans and show that young adults exhibit a sharp boundary at 35-40 glutamines associated with the appearance of protein aggregates and loss of motility. Surprisingly, genetically identical animals expressing near-threshold polyQ repeats exhibited a high degree of variation in the appearance of protein aggregates and cellular toxicity that was dependent on repeat length and exacerbated during aging. The role of genetically determined aging pathways in the progression of age-dependent polyQ-mediated aggregation and cellular toxicity was tested by expressing Q82 in the background of age-1 mutant animals that exhibit an extended lifespan. We observed a dramatic delay of polyQ toxicity and appearance of protein aggregates. These data provide experimental support for the threshold hypothesis of polyQ-mediated toxicity in an experimental organism and emphasize the importance of the threshold as a point at which genetic modifiers and aging influence biochemical environment and protein homeostasis in the cell.

title: Hmga2 Promotes Neural Stem Cell Self-Renewal in Young but Not Old Mice by Reducing p16Ink4a and p19Arf Expression

text: Stem cells persist throughout life in diverse tissues by undergoing self-renewing divisions. Self-renewal capacity declines with age, partly because of increasing expression of the tumor suppressor p16(Ink4a). We discovered that the Hmga2 transcriptional regulator is highly expressed in fetal neural stem cells but that expression declines with age. This decrease is partly caused by the increasing expression of let-7b microRNA, which is known to target HMGA2. Hmga2-deficient mice show reduced stem cell numbers and self-renewal throughout the central and peripheral nervous systems of fetal and young-adult mice but not old-adult mice. Furthermore, p16(Ink4a) and p19(Arf) expression were increased in Hmga2-deficient fetal and young-adult stem cells, and deletion of p16(Ink4a) and/or p19(Arf) partially restored self-renewal capacity. let-7b overexpression reduced Hmga2 and increased p16(Ink4a)/p19(Arf) expression. Hmga2 thus promotes fetal and young-adult stem cell self-renewal by decreasing p16(Ink4a)/p19(Arf) expression. Changes in let-7 and Hmga2 expression during aging contribute to the decline in neural stem cell function.

title: Decrease of learning capacity in offspring with increasing paternal age in the rat.

text: The same 15 male Wistar rats at the ages of 2.5, 6, 10, 14, 18, and 22 months were successively randomly mated with 2.5-month-old females. In a separate experiment, 15 male Wistar rats at the age of 2.5 months and 15 at the age of 23 months were simultaneously randomly mated with 2.5-month-old females. Offspring were evaluated in regard to the mean number per litter, sex ratio, frequency of gross external malformations, growth pattern, and mortality in the first 13 weeks of life and reproductive capacity at 13 weeks of age. They were also evaluated for spontaneous activity and emotionality with an open field test and for learning capacity with an avoidance conditioning test, both carried out between 10 and 13 weeks of age. Only learning capacity of the offspring, expressed in percentage of success for male or female, decreased consistently and significantly as the father's age increased. But females did not seem to be affected in the same way as males. The genetic implications are briefly discussed.

title: Requirement for the ERI/DICER complex in endogenous RNA interference and sperm development in Caenorhabditis elegans.

text: Small regulatory RNAs are key regulators of gene expression. One class of small regulatory RNAs, termed the endogenous small interfering RNAs (endo siRNAs), is thought to negatively regulate cellular transcripts via an RNA interference (RNAi)-like mechanism termed endogenous RNAi (endo RNAi). A complex of proteins composed of ERI-1/3/5, RRF-3, and DICER (the ERI/DICER complex) mediates endo RNAi processes in Caenorhabditis elegans. We conducted a genetic screen to identify additional components of the endo RNAi machinery. Our screen recovered alleles of eri-9, which encodes a novel DICER-interacting protein, and a missense mutation within the helicase domain of DICER [DCR-1(G492R)]. ERI-9(-) and DCR-1(G492) animals exhibit defects in endo siRNA expression and a concomitant failure to regulate mRNAs that exhibit sequence homology to these endo siRNAs, indicating that ERI-9 and the DCR-1 helicase domain function in the C. elegans endo RNAi pathway. We define a subset of Eri mutant animals (including eri-1, rrf-3, eri-3, and dcr-1, but not eri-9 or ergo-1) that exhibit temperature-sensitive, sperm-specific sterility and defects in X chromosome segregation. Among these mutants we find multiple aberrations in sperm development beginning with cytokinesis and extending through terminal differentiation. These results identify novel components of the endo RNAi machinery, demonstrate differential requirements for the Eri factors in the sperm-producing germline, and begin to delineate the functional requirement for the ERI/DICER complex in sperm development.

title: Economic implications of nighttime attending intensivist coverage in a medical intensive care unit.

text:
OBJECTIVE Our objective was to assess the cost implications of changing the intensive care unit staffing model from on-demand presence to mandatory 24-hr in-house critical care specialist presence.
 DESIGN A pre-post comparison was undertaken among the prospectively assessed cohorts of patients admitted to our medical intensive care unit 1 yr before and 1 yr after the change. Our data were stratified by Acute Physiology and Chronic Health Evaluation III quartile and whether a patient was admitted during the day or at night. Costs were modeled using a generalized linear model with log-link and γ-distributed errors.
 SETTING A large academic center in the Midwest.
 PATIENTS All patients admitted to the adult medical intensive care unit on or after January 1, 2005 and discharged on or before December 31, 2006. Patients receiving care under both staffing models were excluded.
 INTERVENTION Changing the intensive care unit staffing model from on-demand presence to mandatory 24-hr in-house critical care specialist presence.
 MEASUREMENTS AND MAIN RESULTS Total cost estimates of hospitalization were calculated for each patient starting from the day of intensive care unit admission to the day of hospital discharge. Adjusted mean total cost estimates were 61% lower in the post period relative to the pre period for patients admitted during night hours (7 pm to 7 am) who were in the highest Acute Physiology and Chronic Health Evaluation III quartile. No significant differences were seen at other severity levels. The unadjusted intensive care unit length of stay fell in the post period relative to the pre period (3.5 vs. 4.8) with no change in non-intensive care unit length of stay.
 CONCLUSIONS We find that 24-hr intensive care unit intensivist staffing reduces lengths of stay and cost estimates for the sickest patients admitted at night. The costs of introducing such a staffing model need to be weighed against the potential total savings generated for such patients in smaller intensive care units, especially ones that predominantly care for lower-acuity patients.

title: In vivo proliferation and cell cycle kinetics of long-term self-renewing hematopoietic stem cells.

text: A rare set of hematopoietic stem cells (HSC) must undergo a massive expansion to produce mature blood cells. The phenotypic isolation of HSC from mice offers the opportunity to determine directly their proliferation kinetics. We analyzed the proliferation and cell cycle kinetics of long-term self-renewing HSC (LT-HSC) in normal adult mice. At any one time, approximately 5% of LT-HSC were in S/G2/M phases of the cell cycle and another 20% were in G1 phase. BrdUrd incorporation was used to determine the rate at which different cohorts of HSC entered the cell cycle over time. About 50% of LT-HSC incorporated BrdUrd by 6 days and >90% incorporated BrdUrd by 30 days. By 6 months, 99% of LT-HSC had incorporated BrdUrd. We calculated that approximately 8% of LT-HSC asynchronously entered the cell cycle per day. Nested reverse transcription-PCR analysis revealed cyclin D2 expression in a high proportion of LT-HSC. Although approximately 75% of LT-HSC are quiescent in G0 at any one time, all HSC are recruited into cycle regularly such that 99% of LT-HSC divide on average every 57 days.

title: High and low fat consumers, their macronutrient intake and body mass index: further analysis of the National Diet and Nutrition Survey of British Adults.

text:
OBJECTIVES To explore the different characteristics of high and low fat consumers, in particular their macronutrient intake and body mass index.
 DESIGN Reanalysis of data from the Dietary and Nutritional Survey of British Adults. Comparisons were made between groups defined as high and low fat consumers on the basis of 7-day weighed food records considered to be valid for energy intake. Individuals were classified in two ways according to the percentage energy from fat (FAT%) and the absolute amount of fat consumed (FATg). The criteria for classification of the high FAT% being > 45% (high fat) and < or = 35% (low fat). For the FATg group the threshold for the high fat group was > 138 g/day (men) and > 102 g/day (women), and for the low fat group < 85 g/day (men) and < 70 g/day (women).
 SETTING Dietary data was collected from private households in Great Britain between 1986 and 1987.    SUBJECTS From the total population of 2197, individuals who were slimming, ill or had an EI: BMR of < 1.2 were excluded in order to use data which was most likely to represent habitual energy intakes. From the remaining 1240 subjects, 10.8% of this sample (6.1% of the total population) were classified as low fat consumers (76 men and 58 women) and 15.4% high fat (8.7% of the total population, 93 men and 98 women).
 MAIN OUTCOME MEASURES Macronutrient consumption and body mass index (BMI).
 RESULTS 30% of the subjects changed fat group classification when the criteria of defining high and low fat groups altered from FAT% to FATg. Nutrient intakes differed according to definition of the groups. The high fat FATg group ate significantly more of all nutrients than the low fat FATg group. However, this was not seen for the FAT% analysis, with the high fat group eating more fat and less carbohydrate. The average BMI tended to be higher in the high fat than the low fat groups, particularly in the FATg analysis. However, the high fat group contained a wide range of BMIs. Further exploration of BMI in the high fat groups, showed that age (an 11-year difference) was the only variable to distinguish individuals in the top and bottom quartiles of BMI.
 CONCLUSIONS High and low fat consumers differ according to a number of variables, and this is affected by how these groups are defined (FAT% or FATg). High fat consumers tend to have a higher BMI than low fat consumers, but not all high fat consumers are overweight or obese.

title: Liraglutide improves hippocampal synaptic plasticity associated with increased expression of Mash1 in ob/ob mice

text: Objective:Consumption of high-fat diet exerts adverse effects on learning and memory formation, which is linked to impaired hippocampal function. Activation of glucagon-like peptide-1 (GLP-1) signalling ameliorates detrimental effects of obesity-diabetes on cognitive function; however, mechanisms underlying these beneficial actions remain unclear. This study examined effects of daily subcutaneous treatment with GLP-1 mimetic, Liraglutide, on synaptic plasticity, hippocampal gene expression and metabolic control in adult obese diabetic (ob/ob) mice. Results:Long-term potentiation (LTP) induced by area CA1 was completely abolished in ob/ob mice compared with lean controls. Deleterious effects on LTP were rescued (P<0.001) with Liraglutide. Indeed, Liraglutide-treated mice exhibited superior LTP profile compared with lean controls (P<0.01). Expression of hippocampal brain-derived neurotropic factor and neurotrophic tyrosine kinase receptor-type 2 were not significantly different, but synaptophysin and Mash1 were decreased in ob/ob mice. Treatment with Liraglutide over 21 days increased expression of Mash1 in ob/ob mice (2.0-fold; P<0.01). These changes were associated with significantly reduced plasma glucose (21% reduction; P<0.05) and markedly improved plasma insulin concentrations (2.1- to 3.3-fold; P<0.05 to P<0.01). Liraglutide also significantly reduced the glycaemic excursion following an intraperitonal glucose load (area under curve (AUC) values: 22%; P<0.05) and markedly enhanced the insulin response to glucose (AUC values: 1.6-fold; P<0.05). O2 consumption, CO2 production, respiratory exchange ratio and energy expenditure were not altered by Liraglutide therapy. On day 21, accumulated food intake (32% reduction; P<0.05) and number of feeding bouts (32% reduction; P<0.05) were significantly reduced but simple energy restriction was not responsible for the beneficial actions of Liraglutide. Conclusion:Liraglutide elicits beneficial effects on metabolic control and synaptic plasticity in mice with severe obesity and insulin resistance mediated in part through increased expression of Mash1 believed to improve hippocampal neurogenesis and cell survival.

title: Radiotherapy plus concomitant and adjuvant temozolomide for glioblastoma.

text:
BACKGROUND Glioblastoma, the most common primary brain tumor in adults, is usually rapidly fatal. The current standard of care for newly diagnosed glioblastoma is surgical resection to the extent feasible, followed by adjuvant radiotherapy. In this trial we compared radiotherapy alone with radiotherapy plus temozolomide, given concomitantly with and after radiotherapy, in terms of efficacy and safety.
 METHODS Patients with newly diagnosed, histologically confirmed glioblastoma were randomly assigned to receive radiotherapy alone (fractionated focal irradiation in daily fractions of 2 Gy given 5 days per week for 6 weeks, for a total of 60 Gy) or radiotherapy plus continuous daily temozolomide (75 mg per square meter of body-surface area per day, 7 days per week from the first to the last day of radiotherapy), followed by six cycles of adjuvant temozolomide (150 to 200 mg per square meter for 5 days during each 28-day cycle). The primary end point was overall survival.
 RESULTS A total of 573 patients from 85 centers underwent randomization. The median age was 56 years, and 84 percent of patients had undergone debulking surgery. At a median follow-up of 28 months, the median survival was 14.6 months with radiotherapy plus temozolomide and 12.1 months with radiotherapy alone. The unadjusted hazard ratio for death in the radiotherapy-plus-temozolomide group was 0.63 (95 percent confidence interval, 0.52 to 0.75; P<0.001 by the log-rank test). The two-year survival rate was 26.5 percent with radiotherapy plus temozolomide and 10.4 percent with radiotherapy alone. Concomitant treatment with radiotherapy plus temozolomide resulted in grade 3 or 4 hematologic toxic effects in 7 percent of patients.
 CONCLUSIONS The addition of temozolomide to radiotherapy for newly diagnosed glioblastoma resulted in a clinically meaningful and statistically significant survival benefit with minimal additional toxicity.

title: Once-a-day Concerta methylphenidate versus three-times-daily methylphenidate in laboratory and natural settings.

text:
OBJECTIVE Methylphenidate (MPH), the most commonly prescribed drug for attention-deficit/hyperactivity disorder (ADHD), has a short half-life, which necessitates multiple daily doses. The need for multiple doses produces problems with medication administration during school and after-school hours, and therefore with compliance. Previous long-acting stimulants and preparations have shown effects equivalent to twice-daily dosing of MPH. This study tests the efficacy and duration of action, in natural and laboratory settings, of an extended-release MPH preparation designed to last 12 hours and therefore be equivalent to 3-times-daily dosing.
 METHODS Sixty-eight children with ADHD, 6 to 12 years old, participated in a within-subject, double-blind comparison of placebo, immediate-release (IR) MPH 3 times a day (tid), and Concerta, a once-daily MPH formulation. Three dosing levels of medication were used: 5 mg IR MPH tid/18 mg Concerta once a day (qd); 10 mg IR MPH tid/36 mg Concerta qd; and 15 mg IR MPH tid/54 mg Concerta qd. All children were currently medicated with MPH at enrollment, and each child's dose level was based on that child's MPH dosing before the study. The doses of Concerta were selected to be comparable to the daily doses of MPH that each child received. To achieve the ascending rate of MPH delivery determined by initial investigations to provide the necessary continuous coverage, Concerta doses were 20% higher on a daily basis than a comparable tid regimen of IR MPH. Children received each medication condition for 7 days. The investigation was conducted in the context of a background clinical behavioral intervention in both the natural environment and the laboratory setting. Parents received behavioral parent training and teachers were taught to establish a school-home daily report card (DRC). A DRC is a list of individual target behaviors that represent a child's most salient areas of impairment. Teachers set daily goals for each child's impairment targets, and parents provided rewards at home for goal attainment. Each weekday, teachers completed the DRC, and it was used as a dependent measure of individualized medication response. Teachers and parents also completed weekly standardized ratings of behavior and treatment effectiveness. To evaluate the time course of medication effects, children spent 12 hours in a laboratory setting on Saturdays and medication effects were measured using procedures and methods adapted from our summer treatment program. Measures of classroom behavior and academic productivity/accuracy were taken in a laboratory classroom setting during which children completed independent math and reading worksheets. Measures of social behavior were taken in structured, small-group board game settings and unstructured recess settings. Measures included behavior frequency counts, academic problems completed and accuracy, independent observations, teacher and counselor ratings, and individualized behavioral target goals. Reports of adverse events, sleep quality, and appetite were collected.
 RESULTS On virtually all measures in all settings, both drug conditions were significantly different from placebo, and the 2 drugs were not different from each other. In children's regular school settings, both medications improved behavior as measured by teacher ratings and individualized target behaviors (the DRC); these effects were seen into the evening as measured by parent ratings. In the laboratory setting, effects of Concerta were equivalent to tid MPH and lasted at least through 12 hours after dosing. Concerta was significantly superior to tid MPH on 2 parent rating scores, and when asked, more parents preferred Concerta than preferred tid IR MPH or placebo. Side effects on children's sleep and appetite were similar for the 2 preparations. In the lab setting, both medications improved productivity and accuracy on arithmetic seatwork assignments, disruptive and on-task behavior, and classroom rule following. Both medications improved children's rule following and negative behavior in small group board games, as well as in unstructured recess settings. Individual target behaviors also showed significant improvement with medication across domains in the laboratory setting. Children's behavior across settings deteriorated across the laboratory day, and the primary effect of medication was to prevent this deterioration as the day wore on. Results support the use of background behavioral treatment in clinical trials of stimulant medication, and illustrate the utility of a measure of individualized daily target goals (ie, the DRC) as an objective measure of medication response in both the laboratory and natural school settings.
 CONCLUSION This investigation clearly supports the efficacy of the Concerta long-acting formulation of MPH for parents who desire to have medication benefits for their child throughout the day and early evening. (ABSTRACT TRUNCATED)

title: Rejuvenation of aged progenitor cells by exposure to a young systemic environment

text: The decline of tissue regenerative potential is a hallmark of ageing and may be due to age-related changes in tissue-specific stem cells. A decline in skeletal muscle stem cell (satellite cell) activity due to a loss of Notch signalling results in impaired regeneration of aged muscle. The decline in hepatic progenitor cell proliferation owing to the formation of a complex involving cEBP-α and the chromatin remodelling factor brahma (Brm) inhibits the regenerative capacity of aged liver. To examine the influence of systemic factors on aged progenitor cells from these tissues, we established parabiotic pairings (that is, a shared circulatory system) between young and old mice (heterochronic parabioses), exposing old mice to factors present in young serum. Notably, heterochronic parabiosis restored the activation of Notch signalling as well as the proliferation and regenerative capacity of aged satellite cells. The exposure of satellite cells from old mice to young serum enhanced the expression of the Notch ligand (Delta), increased Notch activation, and enhanced proliferation in vitro. Furthermore, heterochronic parabiosis increased aged hepatocyte proliferation and restored the cEBP-α complex to levels seen in young animals. These results suggest that the age-related decline of progenitor cell activity can be modulated by systemic factors that change with age.

title: Effects of Bifidobacterium animalis administered during lactation on allergic and autoimmune responses in rodents.

text: Probiotics are promoted as being beneficial to health and positive effects on the immune system have been reported. Beneficial immune effects have been attributed to several mechanisms, including stimulating T helper 1 (Th1) immunity. To explore the effects of the probiotic Bifidobacterium animalis on Th1- and Th2-mediated immune responses, two different animal models representing either Th1- or Th2-mediated immune responses were used: a rat model for experimental autoimmune encephalomyelitis (EAE) (Th1) and a mouse model for respiratory allergy induced by ovalbumin (OVA) (Th2). B. animalis administration started when the mice or rats were 2 weeks old. Respiratory allergy or EAE were induced when the animals were 6-7 weeks old. In the allergy model, B. animalis modestly reduced the number of infiltrating eosinophils and lymphocytes in the lungs, but no effects on allergen-specific serum immunoglobulin E levels were found. Cytokine profiles assessed after culturing spleen cells with the mitogen concanvalin A (ConA) showed that B. animalis skewed the Th1/Th2 balance towards Th1 in females. However, allergen-induced cytokine production in females was not affected by B. animalis. In males, B. animalis significantly decreased ConA-induced interleukin-13 and a trend towards lower levels of OVA-induced Th2 cytokines. In the EAE model, B. animalis significantly reduced the duration of clinical symptoms by almost 2 days in males and improved the body weight gain during the experimental period compared with the control group. Our data show that B. animalis reduced several immune parameters in the allergy as well as in the autoimmunity model.

title: High levels of viral replication contrast with only transient changes in CD4(+) and CD8(+) cell numbers during the early phase of experimental infection with simian immunodeficiency virus SIVmnd-1 in Mandrillus sphinx.

text: Early events during human immunodeficiency virus infections are considered to reflect the capacity of the host to control infection. We have studied early virus and host parameters during the early phase of simian immunodeficiency virus SIVmnd-1 nonpathogenic infection in its natural host, Mandrillus sphinx. Four mandrills were experimentally infected with a primary SIVmnd-1 strain derived from a naturally infected mandrill. Two noninfected control animals were monitored in parallel. Blood and lymph nodes were collected at three time points before infection, twice a week during the first month, and at days 60, 180, and 360 postinfection (p.i.). Anti-SIVmnd-1 antibodies were detected starting from days 28 to 32 p.i. Neither elevated temperature nor increased lymph node size were observed. The viral load in plasma peaked between days 7 to 10 p.i. (2 x 10(6) to 2 x 10(8) RNA equivalents/ml). Viremia then decreased 10- to 1,000-fold, reaching the viral set point between days 30 to 60 p.i. The levels during the chronic phase of infection were similar to that in the naturally infected donor mandrill (2 x 10(5) RNA equivalents/ml). The CD4(+) cell numbers and percentages in blood and lymph nodes decreased slightly (<10%) during primary infection, and CD8(+) cell numbers increased transiently. All values returned to preinfection infection levels by day 30 p.i. CD8(+) cell numbers or percentages, in peripheral blood and lymph nodes, did not increase during the 1 year of follow-up. In conclusion, SIVmnd-1 has the capacity for rapid and extensive replication in mandrills. Despite high levels of viremia, CD4(+) and CD8(+) cell numbers remained stable in the post-acute phase of infection, raising questions regarding the susceptibility of mandrill T cells to activation and/or cell death in response to SIVmnd-1 infection in vivo.

title: Cardiovascular risk factors in childhood and carotid artery intima-media thickness in adulthood: the Cardiovascular Risk in Young Finns Study.

text:
CONTEXT Exposure to cardiovascular risk factors during childhood and adolescence may be associated with the development of atherosclerosis later in life.
 OBJECTIVE To study the relationship between cardiovascular risk factors measured in childhood and adolescence and common carotid artery intima-media thickness (IMT), a marker of preclinical atherosclerosis, measured in adulthood.
 DESIGN, SETTING, AND PARTICIPANTS Population-based, prospective cohort study conducted at 5 centers in Finland among 2229 white adults aged 24 to 39 years who were examined in childhood and adolescence at ages 3 to 18 years in 1980 and reexamined 21 years later, between September 2001 and January 2002.
 MAIN OUTCOME MEASURES Association between cardiovascular risk variables (levels of low-density lipoprotein cholesterol [LDL-C], high-density lipoprotein cholesterol [HDL-C], and triglycerides; LDL-C/HDL-C ratio; systolic and diastolic blood pressure; body mass index; smoking) measured in childhood and adulthood and common carotid artery IMT measured in adulthood.
 RESULTS In multivariable models adjusted for age and sex, IMT in adulthood was significantly associated with childhood LDL-C levels (P =.001), systolic blood pressure (P<.001), body mass index (P =.007), and smoking (P =.02), and with adult systolic blood pressure (P<.001), body mass index (P<.001), and smoking (P =.004). The number of risk factors measured in 12- to 18-year-old adolescents, including high levels (ie, extreme age- and sex-specific 80th percentile) of LDL-C, systolic blood pressure, body mass index, and cigarette smoking, were directly related to carotid IMT measured in young adults at ages 33 through 39 years (P<.001 for both men and women), and remained significant after adjustment for contemporaneous risk variables. The number of risk factors measured at ages 3 to 9 years demonstrated a weak direct relationship with carotid IMT at ages 24 to 30 years in men (P =.02) but not in women (P =.63).
 CONCLUSIONS Risk factor profile assessed in 12- to 18-year-old adolescents predicts adult common carotid artery IMT independently of contemporaneous risk factors. These findings suggest that exposure to cardiovascular risk factors early in life may induce changes in arteries that contribute to the development of atherosclerosis.

title: Sex-specific effects of the DAF-12 steroid receptor on aging in Caenorhabditis elegans.

text: Sex differences in longevity and aging are seen throughout the animal kingdom. These are likely to result, in part, from sex differences in endocrinology. In the nematode Caenorhabditis elegans, males are the longer-lived sex. Here we explore the possibility that sex differences in insulin/insulin-like growth factor 1 (IGF-1) and steroid endocrinology contribute to this sex difference in aging by studying C. elegans populations in liquid culture. We report that in hermaphrodite populations, mutational loss of the DAF-12 steroid receptor affected life span as in previous plate-culture studies: mutant longevity is suppressed in a weak daf-2 insulin/IGF-1 receptor mutant but enhanced in a stronger daf-2 mutant. However, in males, mutation of daf-12 had little effect on aging in either weak or strong daf-2 mutants. Moreover, while mutation of daf-12 marginally reduced life span in daf-2(+) hermaphrodites, as in plate-cultured populations, it did not in daf-2(+) males. These results could imply that in C. elegans, as in mammals, sex differences in steroid endocrinology contribute to sex differences in aging.

title: Early loss of interneurons and delayed subunit-specific changes in GABA(A)-receptor expression in a mouse model of mesial temporal lobe epilepsy.

text: Unilateral injection of kainic acid (KA) into the dorsal hippocampus of adult mice induces spontaneous recurrent partial seizures and replicates histopathological changes observed in human mesial temporal lobe epilepsy (MTLE) (Bouilleret V et al., Neuroscience 1999; 89:717-729). Alterations in pre- and postsynaptic components of GABAergic neurotransmission were investigated immunohistochemically at different time points (1-120 days) in this mouse model of MTLE. Markers of GABAergic interneurons (parvalbumin, calbindin-D28k, and calretinin), the type-1 GABA transporter (GAT1), and major GABA(A)-receptor subunits expressed in the hippocampal formation were analyzed. Acutely, KA injection produced a profound loss of hilar cells but only limited damage to CA1 and CA3 pyramidal cells. In addition, parvalbumin and calbindin-D28k staining of interneurons disappeared irreversibly in CA1 and dentate gyrus (DG), whereas calretinin staining was spared. The prominent GABA(A)-receptor alpha1 subunit staining of interneurons also disappeared after KA treatment, suggesting acute degeneration of these cells. Likewise, GAT1 immunoreactivity revealed degenerating terminals at 24 h post-KA in CA1 and DC and subsided almost completely thereafter. Loss of CA1 and, to a lesser extent, CA3 neurons became evident at 7-15 days post-KA. It was more accentuated after 1 month, accompanied by a corresponding reduction of GABA(A)-receptor staining. In contrast, DC granule cells were markedly enlarged and dispersed in the molecular layer and exhibited a prominent increase in GABA(A)-receptor subunit staining. After 4 months, the dorsal CA1 area was lost almost entirely, CA3 was reduced, and the DG represented most of the remaining dorsal hippocampal formation. No significant morphological alterations were detected contralaterally. These results suggest that loss of hilar cells and GABAergic neurons contributes to epileptogenesis in this model of MTLE. In contrast, long-term degeneration of pyramidal cells and granule cell dispersion may reflect distinct responses to recurrent seizures. Finally, GABA(A)-receptor upregulation in the DG may represent a compensatory response persisting for several months in epileptic mice.

title: MicroRNAs: small RNAs with a big role in gene regulation

text: Key PointsMicroRNAs (miRNAs) are a family of ∼21–25-nucleotide small RNAs that negatively regulate gene expression at the post-transcriptional level. The founding members of the miRNA family, lin-4 and let-7, were identified through genetic screens for defects in the temporal regulation of Caenorhabditis elegans larval development. Owing to genome-wide cloning efforts, hundreds of miRNAs have now been identified in almost all metazoans, including flies, plants and mammals. MiRNAs exhibit temporally and spatially regulated expression patterns during diverse developmental and physiological processes. Most of the miRNAs that have been characterized so far seem to regulate aspects of development, including larval developmental transitions and neuronal development in C. elegans, growth control and apoptosis in Drosophila melanogaster, haematopoietic differentiation in mammals, and leaf development, flower development and embryogenesis in Arabidopsis thaliana. The majority of the animal miRNAs that have been characterized so far affect protein synthesis from their target mRNAs. On the other hand, most of the plant miRNAs studied so far direct the cleavage of their targets. The degree of complementarity between a miRNA and its target, at least in part, determines the regulatory mechanism. In animals, primary transcripts of miRNAs are processed sequentially by two RNase-III enzymes, Drosha and Dicer, into a small, imperfect dsRNA duplex (miRNA:miRNA*) that contains both the mature miRNA strand and its complementary strand (miRNA*). Relative instability at the 5′ end of the mature miRNA leads to the asymmetric assembly of the mature miRNA into the effector complex, the RNA-induced silencing complex (RISC).Ago proteins are a key component of the RISC. Multiple Ago homologues in various metazoan genomes indicate the existence of multiple RISCs that carry out related but specific biological functions. Bioinformatic prediction of miRNA targets has provided an important tool to explore the functions of miRNAs. However, the overall success rate of such predictions remains to be determined by experimental validation. AbstractMicroRNAs are a family of small, non-coding RNAs that regulate gene expression in a sequence-specific manner. The two founding members of the microRNA family were originally identified in Caenorhabditis elegans as genes that were required for the timed regulation of developmental events. Since then, hundreds of microRNAs have been identified in almost all metazoan genomes, including worms, flies, plants and mammals. MicroRNAs have diverse expression patterns and might regulate various developmental and physiological processes. Their discovery adds a new dimension to our understanding of complex gene regulatory networks.

title: Dietary quality among men and women in 187 countries in 1990 and 2010: a systematic assessment

text:
BACKGROUND Healthy dietary patterns are a global priority to reduce non-communicable diseases. Yet neither worldwide patterns of diets nor their trends with time are well established. We aimed to characterise global changes (or trends) in dietary patterns nationally and regionally and to assess heterogeneity by age, sex, national income, and type of dietary pattern.
 METHODS In this systematic assessment, we evaluated global consumption of key dietary items (foods and nutrients) by region, nation, age, and sex in 1990 and 2010. Consumption data were evaluated from 325 surveys (71·7% nationally representative) covering 88·7% of the global adult population. Two types of dietary pattern were assessed: one reflecting greater consumption of ten healthy dietary items and the other based on lesser consumption of seven unhealthy dietary items. The mean intakes of each dietary factor were divided into quintiles, and each quintile was assigned an ordinal score, with higher scores being equivalent to healthier diets (range 0-100). The dietary patterns were assessed by hierarchical linear regression including country, age, sex, national income, and time as exploratory variables.
 FINDINGS From 1990 to 2010, diets based on healthy items improved globally (by 2·2 points, 95% uncertainty interval (UI) 0·9 to 3·5), whereas diets based on unhealthy items worsened (-2·5, -3·3 to -1·7). In 2010, the global mean scores were 44·0 (SD 10·5) for the healthy pattern and 52·1 (18·6) for the unhealthy pattern, with weak intercorrelation (r=-0·08) between countries. On average, better diets were seen in older adults compared with younger adults, and in women compared with men (p<0·0001 each). Compared with low-income nations, high-income nations had better diets based on healthy items (+2·5 points, 95% UI 0·3 to 4·1), but substantially poorer diets based on unhealthy items (-33·0, -37·8 to -28·3). Diets and their trends were very heterogeneous across the world regions. For example, both types of dietary patterns improved in high-income countries, but worsened in some low-income countries in Africa and Asia. Middle-income countries showed the largest improvement in dietary patterns based on healthy items, but the largest deterioration in dietary patterns based on unhealthy items.
 INTERPRETATION Consumption of healthy items improved, while consumption of unhealthy items worsened across the world, with heterogeneity across regions and countries. These global data provide the best estimates to date of nutrition transitions across the world and inform policies and priorities for reducing the health and economic burdens of poor diet quality.
 FUNDING The Bill & Melinda Gates Foundation and Medical Research Council.


query: 7-day-old adult Caenorhabditis elegans exhibit approximately 75% of the learning capacity seen in 1-day old adults.

title: Insulin Signaling and Dietary Restriction Differentially Influence the Decline of Learning and Memory with Age

text: Of all the age-related declines, memory loss is one of the most devastating. While conditions that increase longevity have been identified, the effects of these longevity-promoting factors on learning and memory are unknown. Here we show that the C. elegans Insulin/IGF-1 receptor mutant daf-2 improves memory performance early in adulthood and maintains learning ability better with age but, surprisingly, demonstrates no extension in long-term memory with age. By contrast, eat-2 mutants, a model of Dietary Restriction (DR), exhibit impaired long-term memory in young adulthood but maintain this level of memory longer with age. We find that crh-1, the C. elegans homolog of the CREB transcription factor, is required for long-term associative memory, but not for learning or short-term memory. The expression of crh-1 declines with age and differs in the longevity mutants, and CREB expression and activity correlate with memory performance. Our results suggest that specific longevity treatments have acute and long-term effects on cognitive functions that decline with age through their regulation of rate-limiting genes required for learning and memory.

title: Neurite sprouting and synapse deterioration in the aging Caenorhabditis elegans nervous system.

text: Caenorhabditis elegans is a powerful model for analysis of the conserved mechanisms that modulate healthy aging. In the aging nematode nervous system, neuronal death and/or detectable loss of processes are not readily apparent, but because dendrite restructuring and loss of synaptic integrity are hypothesized to contribute to human brain decline and dysfunction, we combined fluorescence microscopy and electron microscopy (EM) to screen at high resolution for nervous system changes. We report two major components of morphological change in the aging C. elegans nervous system: (1) accumulation of novel outgrowths from specific neurons, and (2) physical decline in synaptic integrity. Novel outgrowth phenotypes, including branching from the main dendrite or new growth from somata, appear at a high frequency in some aging neurons, but not all. Mitochondria are often associated with age-associated branch sites. Lowered insulin signaling confers some maintenance of ALM and PLM neuron structural integrity into old age, and both DAF-16/FOXO and heat shock factor transcription factor HSF-1 exert neuroprotective functions. hsf-1 can act cell autonomously in this capacity. EM evaluation in synapse-rich regions reveals a striking decline in synaptic vesicle numbers and a diminution of presynaptic density size. Interestingly, old animals that maintain locomotory prowess exhibit less synaptic decline than same-age decrepit animals, suggesting that synaptic integrity correlates with locomotory healthspan. Our data reveal similarities between the aging C. elegans nervous system and mammalian brain, suggesting conserved neuronal responses to age. Dissection of neuronal aging mechanisms in C. elegans may thus influence the development of brain healthspan-extending therapies.

title: Age of ovary determines remaining life expectancy in old ovariectomized mice.

text: We investigated the capacity of young ovaries, transplanted into old ovariectomized CBA mice, to improve remaining life expectancy of the hosts. Donor females were sexually mature 2-month-olds; recipients were prepubertally ovariectomized at 3 weeks and received transplants at 5, 8 or 11 months of age. Relative to ovariectomized control females, life expectancy at 11 months was increased by 60% in 11-month recipient females and by 40% relative to intact control females. Only 20% of the 11-month transplant females died in the 300-day period following ovarian transplantation, whereas nearly 65% of the ovariectomized control females died during this same period. The 11-month-old recipient females resumed oestrus and continued to cycle up to several months beyond the age of control female reproductive senescence. Across the three recipient age groups, transplantation of young ovaries increased life expectancy in proportion to the relative youth of the ovary. Our results relate to recent findings on the gonadal input upon aging in Caenorhabditis elegans and may suggest how the mammalian gonad, including that of humans, could regulate aging and determine longevity.

title: The threshold for polyglutamine-expansion protein aggregation and cellular toxicity is dynamic and influenced by aging in Caenorhabditis elegans.

text: Studies of the mutant gene in Huntington's disease, and for eight related neurodegenerative disorders, have identified polyglutamine (polyQ) expansions as a basis for cellular toxicity. This finding has led to a disease hypothesis that protein aggregation and cellular dysfunction can occur at a threshold of approximately 40 glutamine residues. Here, we test this hypothesis by expression of fluorescently tagged polyQ proteins (Q29, Q33, Q35, Q40, and Q44) in the body wall muscle cells of Caenorhabditis elegans and show that young adults exhibit a sharp boundary at 35-40 glutamines associated with the appearance of protein aggregates and loss of motility. Surprisingly, genetically identical animals expressing near-threshold polyQ repeats exhibited a high degree of variation in the appearance of protein aggregates and cellular toxicity that was dependent on repeat length and exacerbated during aging. The role of genetically determined aging pathways in the progression of age-dependent polyQ-mediated aggregation and cellular toxicity was tested by expressing Q82 in the background of age-1 mutant animals that exhibit an extended lifespan. We observed a dramatic delay of polyQ toxicity and appearance of protein aggregates. These data provide experimental support for the threshold hypothesis of polyQ-mediated toxicity in an experimental organism and emphasize the importance of the threshold as a point at which genetic modifiers and aging influence biochemical environment and protein homeostasis in the cell.

title: Hmga2 Promotes Neural Stem Cell Self-Renewal in Young but Not Old Mice by Reducing p16Ink4a and p19Arf Expression

text: Stem cells persist throughout life in diverse tissues by undergoing self-renewing divisions. Self-renewal capacity declines with age, partly because of increasing expression of the tumor suppressor p16(Ink4a). We discovered that the Hmga2 transcriptional regulator is highly expressed in fetal neural stem cells but that expression declines with age. This decrease is partly caused by the increasing expression of let-7b microRNA, which is known to target HMGA2. Hmga2-deficient mice show reduced stem cell numbers and self-renewal throughout the central and peripheral nervous systems of fetal and young-adult mice but not old-adult mice. Furthermore, p16(Ink4a) and p19(Arf) expression were increased in Hmga2-deficient fetal and young-adult stem cells, and deletion of p16(Ink4a) and/or p19(Arf) partially restored self-renewal capacity. let-7b overexpression reduced Hmga2 and increased p16(Ink4a)/p19(Arf) expression. Hmga2 thus promotes fetal and young-adult stem cell self-renewal by decreasing p16(Ink4a)/p19(Arf) expression. Changes in let-7 and Hmga2 expression during aging contribute to the decline in neural stem cell function.

title: Human somatic cell nuclear transfer using adult cells.

text: Derivation of patient-specific human pluripotent stem cells via somatic cell nuclear transfer (SCNT) has the potential for applications in a range of therapeutic contexts. However, successful SCNT with human cells has proved challenging to achieve, and thus far has only been reported with fetal or infant somatic cells. In this study, we describe the application of a recently developed methodology for the generation of human ESCs via SCNT using dermal fibroblasts from 35- and 75-year-old males. Our study therefore demonstrates the applicability of SCNT for adult human cells and supports further investigation of SCNT as a strategy for regenerative medicine.

title: B-catenin deficiency, but not Myc deletion, suppresses the immediate phenotypes of APC loss in the liver.

text: Dysregulated Wnt signaling is seen in approximately 30% of hepatocellular carcinomas; thus, finding pathways downstream of the activation of Wnt signaling is key. Here, using cre-lox technology, we deleted the Apc gene in the adult mouse liver and observed a rapid increase in nuclear beta-catenin and c-Myc, which is associated with an induction of proliferation that led to hepatomegaly within 4 days of gene deletion. To investigate the downstream pathways responsible for these phenotypes, we analyzed the impact of inactivating APC in the context of deficiency of the potentially key effectors beta-catenin and c-Myc. beta-catenin loss rescues both the proliferation and hepatomegaly phenotypes after APC loss. However, c-Myc deletion, which rescues the phenotypes of APC loss in the intestine, had no effect on the phenotypes of APC loss in the liver. The consequences of the deregulation of the Wnt pathway within the liver are therefore strikingly different from those observed within the intestine, with the vast majority of Wnt targets being beta-catenin-dependent but c-Myc-independent in the liver.

title: Caloric restriction delays age-related methylation drift

text: In mammals, caloric restriction consistently results in extended lifespan. Epigenetic information encoded by DNA methylation is tightly regulated, but shows a striking drift associated with age that includes both gains and losses of DNA methylation at various sites. Here, we report that epigenetic drift is conserved across species and the rate of drift correlates with lifespan when comparing mice, rhesus monkeys, and humans. Twenty-two to 30-year-old rhesus monkeys exposed to 30% caloric restriction since 7-14 years of age showed attenuation of age-related methylation drift compared to ad libitum-fed controls such that their blood methylation age appeared 7 years younger than their chronologic age. Even more pronounced effects were seen in 2.7-3.2-year-old mice exposed to 40% caloric restriction starting at 0.3 years of age. The effects of caloric restriction on DNA methylation were detectable across different tissues and correlated with gene expression. We propose that epigenetic drift is a determinant of lifespan in mammals. Caloric restriction has been shown to increase lifespan in mammals. Here, the authors provide evidence that age-related methylation drift correlates with lifespan and that caloric restriction in mice and rhesus monkeys results in attenuation of age-related methylation drift.