bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of a 12-Month Exercise Intervention on the Apoptotic Regulating Proteins Bax and Bcl-2 in Colon Crypts: A Randomized Controlled Trial
Authors: Campbell Kristin L. , McTiernan Anne , Li Shuying S. , Sorensen Bess E. , Yasui Yutaka , Lampe Johanna W. , King Irena B. , Ulrich Cornelia M. , Rudolph Rebecca E. , Irwin Melinda L. , Surawicz Christina , Ayub Kamran , Potter John D. , Lampe Paul D. 
Published: September 2007

Abstract
Background: Cellular proliferation and apoptosis (cell death) are highly regulated in the colon as insufficient apoptosis may lead to polyps and cancer. Physical activity decreases risk of colon cancer in observational studies, but the biological basis is not well defined. The objective of this study is to examine the effects of a 12-month aerobic exercise program on expression of proteins that promote (Bax) or inhibit (Bcl-2) apoptosis in colon crypts.
Methods: Two hundred two sedentary participants, 40 to 75 years, were randomly assigned to moderate-to-vigorous intensity exercise for 60 min per day, 6 days per week for 12 months, or usual lifestyle. Colon crypt samples were obtained at baseline and 12 months. Bcl-2 and Bax expression was measured by immunohistochemistry.
Results: Bax density at the bottom of crypts increased in male exercisers versus controls (+0.87 versus −0.18; P = 0.05), whereas the ratio of Bcl-2 to Bax at the bottom and middle of crypts decreased as aerobic fitness (VO2max) increased (P trend = 0.02 and 0.05, respectively). In female exercisers, Bax density in the middle of crypts decreased (−0.36 versus +0.69; P = 0.03) and Bcl-2 to Bax ratio at the top of crypts increased versus controls (+0.46 versus −0.85; P = 0.03). Bax density in the middle of crypts also decreased as minutes per week of exercise increased (P trend = 0.03).
Conclusions: A 12-month exercise intervention resulted in greater expression of proteins that promote apoptosis at the bottom of colon crypts in men and decreased expression of proteins that promote apoptosis at the middle and top of colon crypts in women. The difference in effect by gender and location of observed changes warrants further study. (Cancer Epidemiol Biomarkers Prev 2007;16(9):1767–74)
Plasma Volume Expansion in Pregnancy: Implications for Biomarkers in Population Studies
Authors: Faupel-Badger Jessica M. , Hsieh Chung-Cheng , Troisi Rebecca , Lagiou Pagona , Potischman Nancy 
Published: September 2007

Abstract
There is a growing body of literature focused on endogenous hormone exposures during pregnancy and subsequent cancer risk for both mother and offspring. Examples of these studies include those focused on the biological mechanism for the association of preeclampsia with reduced risk of breast cancer for mother and female offspring or studies that have examined hormone concentrations during pregnancy between different ethnic groups who vary in their rates of breast cancer incidence. Although these studies seem relatively straightforward in conception and analysis, measurement of the concentration of hormones and other biomarkers in pregnant subjects is influenced by plasma volume expansion (PVE). During pregnancy, the maternal plasma volume expands 45% on average to provide for the greater circulatory needs of the maternal organs. Consequently, serum protein and hormone concentrations are greatly altered when comparing the pregnant with nonpregnant state. Assessing PVE also is complicated by the vast individual variation in PVE, ranging from minimal to a 2-fold increase. We propose that PVE needs to be evaluated when comparing biomarker concentrations during pregnancy in two populations that may differ with respect to PVE. Small body size is associated with lower PVE compared with higher body size. Therefore, we hypothesize that variation in PVE will influence the interpretation of differences in biomarker concentrations across population groups with respect to the etiologic significance of the biomarker to the disease under study (e.g., breast cancer). It is possible that some observations may be due only to differences in dilution between the two groups. We present PVE as a topic for consideration in population-based studies, examples of the types of studies where PVE may be relevant, and our own analysis of one such study in the text below. (Cancer Epidemiol Biomarkers Prev 2007;16(9):1720–3)
Adiposity and Sex Hormones in Girls
Authors: Baer Heather J. , Colditz Graham A. , Willett Walter C. , Dorgan Joanne F. 
Published: September 2007

Abstract
Greater body fatness during childhood is associated with reduced risk of premenopausal breast cancer, but few studies have addressed the relation of adiposity with sex hormones in girls. We prospectively examined associations between adiposity and circulating levels of sex hormones and sex hormone–binding globulin (SHBG) among 286 girls in the Dietary Intervention Study in Children. Participants were 8 to 10 years old at baseline and were followed for an average of 7 years. Anthropometric measurements were taken at baseline and at subsequent annual visits, and blood samples were collected every 2 years. Concentrations of dehydroepiandrosterone sulfate (DHEAS) during follow-up were higher among girls with greater body mass index (BMI) at baseline. The mean for the lowest BMI quartile was 63.0 μg/dL compared with 78.8 μg/dL for the highest quartile, and each kg/m2 increment in baseline BMI was associated with a 4.3% increase (95% confidence interval, 1.6-7.0%) in DHEAS levels during follow-up (Ptrend = 0.002). Concentrations of SHBG during follow-up were lower among girls with greater BMI at baseline. The mean for the lowest BMI quartile was 94.8 nmol compared with 57.5 nmol for the highest quartile, and each kg/m2 increment in baseline BMI was associated with an 8.8% decrease (95% confidence interval, 7.0-10.6%) in SHBG levels during follow-up (Ptrend &lt; 0.0001). Estrogen and progesterone concentrations were similar across BMI quartiles. These findings suggest that adiposity may alter DHEAS and SHBG levels in girls. Whether and how these differences affect breast development and carcinogenesis requires further research. (Cancer Epidemiol Biomarkers Prev 2007;16(9):1880–8)
A Prospective Study of Body Size and Breast Cancer in Black Women
Authors: Palmer Julie R. , Adams-Campbell Lucile L. , Boggs Deborah A. , Wise Lauren A. , Rosenberg Lynn 
Published: September 2007

Abstract
The relation of body mass index (BMI) and weight gain to breast cancer risk is complex, and little information is available on Black women, among whom the prevalence of obesity is high. We assessed BMI and weight gain in relation to breast cancer risk in prospective data from the Black Women's Health Study. In 1995, 59,000 African American women enrolled in the Black Women's Health Study by completing mailed questionnaires. Data on anthropometric factors were obtained at baseline and every 2 years afterwards. In 10 years of follow-up, 1,062 incident cases of breast cancer occurred. Incidence rate ratios (IRR) were computed in multivariable Cox proportional hazards regression. BMI at age 18 years of ≥25 relative to &lt;20 was associated with a reduced risk of breast cancer among both premenopausal women (IRR, 0.68; 95% confidence interval, 0.46-0.98) and postmenopausal women (IRR, 0.53; 95% confidence interval, 0.35-0.81). There was an inverse association of current BMI with premenopausal breast cancer but no association with postmenopausal breast cancer, either overall or among never-users of hormone therapy. Weight gain was not associated with postmenopausal breast cancer risk. In analyses restricted to breast cancers that were estrogen and progesterone receptor positive, IRRs for current BMI and weight gain were elevated but not statistically significant. The findings indicate that being overweight at age 18 years is associated with a reduced risk of both premenopausal and postmenopausal breast cancer in African American women. Understanding the reasons for the association may help elucidate the pathways through which adolescent exposures influence breast cancer risk. The lack of association of obesity with receptor-negative tumors in postmenopausal African American women may partially explain why breast cancer incidence in older Black women is not high relative to other ethnic groups in spite of the high prevalence of obesity in Black women. (Cancer Epidemiol Biomarkers Prev 2007;16(9):1795–802)
Early Onset Pancreatic Cancer: Evidence of a Major Role for Smoking and Genetic Factors
Authors: Raimondi Sara , Maisonneuve Patrick , Löhr J-Matthias , Lowenfels Albert B. 
Published: September 2007

Abstract
Pancreatic cancer ranks 4th as a cause of cancer mortality and in ∼5% to 10% of patients, this lethal tumor develops before age 50. We used age-, sex-, and country-specific cancer incidence and mortality data to describe the burden of early onset pancreatic cancer (EOPC) worldwide. We also reviewed the current published evidence on smoking and genetic factors associated with EOPC. We found an excess of EOPC resulting in a substantial number of years-of-life-lost in countries from Central and Eastern Europe. Worldwide, the proportion of EOPC is strongly correlated with lung cancer mortality (R2 = 0.53), suggesting that approximately half of the variation in the proportion of EOPC could be explained by smoking. The unusual pattern of the incidence of pancreatic cancer by gender and race supports the primary role of smoking in the etiology of EOPC: the excess male-to-female rate ratio, attributable mainly to smoking, gradually approaches unity with increasing age. Moreover, male-to-female rate ratios are greater in blacks than in whites only in younger patients. Published studies also identified genetic alterations involved either alone or in association with smoking in the development of EOPC. In conclusion, EOPC constitutes only 1% to 5% of the total deaths from pancreatic cancer worldwide, but is responsible for 20% to 30% of the total number of years-of-life-lost caused by the disease. Smoking and genetic mutations are the major identified risk factors and seem to be even more important for EOPC than for PC in older age groups. (Cancer Epidemiol Biomarkers Prev 2007;16(9):1894–7)
Serologic Response to Oncogenic Human Papillomavirus Types in Male and Female University Students in Busan, South Korea
Authors: Clifford Gary M. , Shin Hai-Rim , Oh Jin-Kyoung , Waterboer Tim , Ju Young-Hee , Vaccarella Salvatore , Quint Wim , Pawlita Michael , Franceschi Silvia 
Published: September 2007

Abstract
In the absence of genital samples, human papillomavirus (HPV) serology may be useful to assess HPV infection in young men and women. HPV seroprevalence and determinants of seropositivity were assessed in 817 female and 518 male university students in Busan, South Korea, of whom 74% and 44%, respectively, reported never having had penetrative sexual intercourse. Type-specific HPV DNA status, assessed by a short PCR fragment primer set, was available from genital samples. Seropositivity to L1 proteins of HPV types 16, 18, 31, 33, 45, 52, and 58 were assessed using multiplex HPV serology. Among women, HPV seroprevalence was significantly higher among sexually active (26.1%) than nonsexually active students [11.1%, odds ratio (OR) = 2.9; 95% confidence interval (95% CI), 1.8-4.7], although the association was weaker than that for HPV DNA prevalence (OR, 14; 95% CI, 4.7-42). Furthermore, HPV seroprevalence was higher among HPV DNA-positive (24%) than HPV DNA-negative women (13%), and there was a positive correlation of type-specific seroprevalence with the presence of HPV DNA of the same type. In contrast, HPV seropositivity among men was not associated with sexual behavior or the presence of HPV DNA. Seroprevalence correlates with genital HPV exposure in young women, but its meaning in young men is unclear. (Cancer Epidemiol Biomarkers Prev 2007;16(9):1874–9)
The Impact of Autoimmune Diseases on the Incidence and Prognosis of Cutaneous Malignant Melanoma
Authors: Kaae Jeanette , Wohlfahrt Jan , Boyd Heather A. , Wulf Hans Christian , Biggar Robert J. , Melbye Mads 
Published: September 2007

Abstract
Background: Persons being treated with IFNα-2b for advanced cutaneous malignant melanoma (CMM) have been reported to have a greatly improved prognosis if they develop autoantibodies or clinical signs of autoimmunity during therapy. Consequently, we examined whether autoimmune diseases might also be associated with lower CMM incidence and better prognosis.
Methods: We established a study cohort based on the entire Danish population, obtaining information on CMM and autoimmune diseases from the Danish national registers. Using log-linear regression models adjusting for age, period, and sex, we compared CMM incidence and CMM-specific mortality rates in persons with and without a history of autoimmune disease.
Results: Between 1977 and 2003, 20,482 cases of CMM were registered in the Danish Cancer Register. Previously diagnosed autoimmune diseases did not affect the incidence of CMM (incidence rate ratio, 1.0; 95% confidence interval, 0.9-1.1). In the first 5 years after CMM diagnosis, we observed 8,957 deaths in individuals with CMM (5,181 expected). CMM-specific mortality rates 1 to 5 years after diagnosis were similar in CMM patients with and without autoimmune diseases (mortality rate ratio, 0.9; 95% confidence interval, 0.7-1.2).
Conclusions: Autoimmune conditions were not associated with CMM incidence or prognosis. The better CMM prognosis previously observed when autoantibodies or clinical signs of autoimmunity developed during IFNα-2b therapy may have been related to variation in individual responses to this therapy, with individuals sensitive to treatment exhibiting more signs of autoimmunity but also (independently) experiencing greater antitumor responses as a result of treatment. (Cancer Epidemiol Biomarkers Prev 2007;16(9):1840–4)
Serum 25(OH)-Vitamin D Concentration and Risk of Esophageal Squamous Dysplasia
Authors: Abnet Christian C. , Chen Wen , Dawsey Sanford M. , Wei Wen-Qiang , Roth Mark J. , Liu Bing , Lu Ning , Taylor Philip R. , Qiao You-Lin 
Published: September 2007

Abstract
Background: Squamous dysplasia is the precursor lesion for esophageal squamous cell carcinoma, and nutritional factors play an important role in the etiology of this cancer. Previous studies using a variety of measures for vitamin D exposure have reached different conclusions about the association between vitamin D and the risk of developing esophageal cancer.
Methods: We measured serum 25-hydroxyvitamin D [25(OH)D] concentrations in a cross-sectional analysis of 720 subjects from Linxian, China, a population at high risk for developing esophageal squamous cell carcinoma. All subjects underwent endoscopy and biopsy and were categorized by the presence or absence of histologic squamous dysplasia. We used crude and multivariate-adjusted generalized linear models to estimate the relative risks (RR) and 95% confidence intervals (95% CI) for the association between squamous dysplasia and sex-specific quartiles of serum 25(OH)D concentration.
Results: Two-hundred and thirty of 720 subjects (32%) had squamous dysplasia. Subjects with dysplasia had significantly higher median serum 25(OH)D concentrations than subjects without dysplasia, 36.5 and 31.5 nmol/L, respectively (Wilcoxon two-sample test, P = 0.0004). In multivariate-adjusted models, subjects in the highest compared with the lowest quartiles were at a significantly increased risk of squamous dysplasia (RR, 1.86; 95% CI, 1.35-2.62). Increased risks were similar when examined in men and women separately: men (RR, 1.74; 95% CI, 1.08-2.93); women (RR, 1.96; 95% CI, 1.28-3.18).
Conclusions: Higher serum 25(OH)D concentrations were associated with significantly increased risk of squamous dysplasia. No obvious source of measured or unmeasured confounding explains this finding. (Cancer Epidemiol Biomarkers Prev 2007;16(9):1889–93)
Increased Expression of Corepressors in Aggressive Androgen-Independent Prostate Cancer Cells Results in Loss of 1α,25-Dihydroxyvitamin D3 Responsiveness
Authors: Ting Huei-Ju , Bao Bo-Ying , Reeder Jay E. , Messing Edward M. , Lee Yi-Fen 
Published: September 2007

Abstract
Vitamin D has antiproliferative activity in prostate cancer; however, resistance to vitamin D–mediated growth inhibition occurs. To investigate the mechanisms of vitamin D resistance, we screened two prostate cancer sublines of CWR22rv1, CWR22R-1, and CWR22R-2, with differential sensitivity to vitamin D. CWR22R-2 showed less response to the antiproliferative effect of vitamin D than CWR22R-1. The vitamin D receptor (VDR)–mediated transcriptional activity was also decreased in CWR22R-2. We further showed that the DNA-binding ability of VDR was decreased and the amount of NCoR in VDR response element was increased in CWR22R-2. Analysis of VDR-associated protein profiles found higher expression of the corepressors, NCoR1 and SMRT, in CWR22R-2 cells. Treatment with the histone deacetylase inhibitor, trichostatin A, increased vitamin D/VDR transcriptional activity and promoted the antiproliferative effect of vitamin D in CWR22R-2 cells. Targeted down-regulation of NCoR1 and SMRT by small interference RNA was able to restore CWR22R-2 response to vitamin D. Together, we showed that increased NCoR1 and SMRT expression in CWR22R-2 cells resulted in reduced VDR-mediated transcriptional activity and attenuated antiproliferative response to vitamin D. Our data suggest that the integrity of the vitamin D/VDR–mediated signaling pathway is crucial in predicting vitamin D responsiveness and thus provide a rational design to improve vitamin D–based treatment efficacy based on molecular profiles of patients. (Mol Cancer Res 2007;5(9):967–80)
Ursolic Acid Inhibits STAT3 Activation Pathway Leading to Suppression of Proliferation and Chemosensitization of Human Multiple Myeloma Cells
Authors: Pathak Ashutosh K. , Bhutani Manisha , Nair Asha S. , Ahn Kwang Seok , Chakraborty Arup , Kadara Humam , Guha Sushovan , Sethi Gautam , Aggarwal Bharat B. 
Published: September 2007

AbstractThe activation of signal transducers and activators of transcription 3 (STAT3) has been linked with the proliferation of a variety of human cancer cells, including multiple myeloma. Agents that can suppress STAT3 activation have potential for prevention and treatment of cancer. In the present report, we tested an agent, ursolic acid, found in basil, apples, prunes, and cranberries, for its ability to suppress STAT3 activation. We found that ursolic acid, a pentacyclic triterpenoid, inhibited both constitutive and interleukin-6–inducible STAT3 activation in a dose- and time-dependent manner in multiple myeloma cells. The suppression was mediated through the inhibition of activation of upstream kinases c-Src, Janus-activated kinase 1, Janus-activated kinase 2, and extracellular signal–regulated kinase 1/2. Vanadate treatment reversed the ursolic acid–induced down-regulation of STAT3, suggesting the involvement of a tyrosine phosphatase. Indeed, we found that ursolic acid induced the expression of tyrosine phosphatase SHP-1 protein and mRNA. Moreover, knockdown of SHP-1 by small interfering RNA suppressed the induction of SHP-1 and reversed the inhibition of STAT3 activation, thereby indicating the critical role of SHP-1 in the action of this triterpene. Ursolic acid down-regulated the expression of STAT3-regulated gene products such as cyclin D1, Bcl-2, Bcl-xL, survivin, Mcl-1, and vascular endothelial growth factor. Finally, ursolic acid inhibited proliferation and induced apoptosis and the accumulation of cells in G1-G0 phase of cell cycle. This triterpenoid also significantly potentiated the apoptotic effects of thalidomide and bortezomib in multiple myeloma cells. Overall, these results suggest that ursolic acid is a novel blocker of STAT3 activation that may have a potential in prevention and treatment of multiple myeloma and other cancers. (Mol Cancer Res 2007;5(9):943–55)
Geldanamycin Anisimycins Activate Rho and Stimulate Rho- and ROCK-Dependent Actin Stress Fiber Formation
Authors: Amiri Anahita , Noei Farahnaz , Feroz Tahir , Lee Jonathan M. 
Published: September 2007

Abstract
Heat shock protein 90 (Hsp90) is a member of the heat shock family of molecular chaperones that regulate protein conformation and activity. Hsp90 regulates multiple cell signaling pathways by controlling the abundance and activity of several important protein kinases and cell cycle–related proteins. In this report, we show that inhibition of Hsp90 by geldanamycin or its derivative, 17-allylamino-17-desmethoxygeldamycin, leads to activation of the Rho GTPase and a dramatic increase in actin stress fiber formation in human tumor cell lines. Inactivation of Rho prevents geldanamycin-induced actin reorganization. Hsp90 inactivation does not alter the appearance of filopodia or lamellipodia and tubulin architecture is not visibly perturbed. Our observations suggest that Hsp90 has an important and specific role in regulating Rho activity and Rho-dependent actin cytoskeleton remodeling. (Mol Cancer Res 2007;5(9):933–42)
Pim-1 Kinase-Dependent Phosphorylation of p21Cip1/WAF1 Regulates Its Stability and Cellular Localization in H1299 Cells
Authors: Zhang Yandong , Wang Zeping , Magnuson Nancy S. 
Published: September 2007

Abstract
Previous studies from our laboratory showed that p21Cip1/WAF1 can be phosphorylated by Pim-1 kinase in vitro, implying that part of the function of Pim-1 might involve influencing the cell cycle. In the present study, site-directed mutagenesis and phosphorylated-specific antibodies were used as tools to identify the sites phosphorylated by Pim-1 and the consequences of this phosphorylation. What we found was that Pim-1 can efficiently phosphorylate p21 on Thr145 in vitro using recombinant protein and in vivo in intact cells. Unexpectedly, we found that Ser146 is a second site that is phosphorylated in vivo, but this phosphorylation event seems to be an indirect result of Pim-1 expression. More importantly, the consequences of phosphorylation of either Thr145 or Ser146 are distinct. When p21 is phosphorylated on Thr145, it localizes to the nucleus and results in the disruption of the association between proliferating cell nuclear antigen and p21. Furthermore, phosphorylation of Thr145 promotes stabilization of p21. On the other hand, when p21 is phosphorylated on Ser146, it localizes primarily in the cytoplasm and the effect of phosphorylation on stability is minimal. Cotransfection of wild-type Pim-1 with p21 increases the rate of proliferation compared with cotransfection of p21 with kinase-dead Pim-1. Knocking down Pim-1 expression greatly decreases the rate of proliferation of H1299 cells and their ability to grow in soft agar. These data suggest that Pim-1 overexpression may contribute to tumorigenesis in part by influencing the cellular localization and stability of p21 and by promoting cell proliferation. (Mol Cancer Res 2007;5(9):909–22)