bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract LB-394: Marijuana use and testicular germ cell tumors
Authors: Trabert Britton , Sigurdson Alice J. , Sweeney Anne M. , Strom Sara S. , McGlynn Katherine A.
Published: February 2011

Introduction: Since the early 1970's the incidence of testicular germ cell tumors (TGCT) in the U.S. has been increasing, however, environmental exposures accounting for this rise have not been identified. Trends in marijuana use have also increased during this period. Chronic marijuana use has been shown to produce adverse effects on the human endocrine and reproductive systems. A prior study of marijuana use and TGCT reported a significant association among frequent and long-term current users. We aimed to evaluate the relationship of marijuana use and TGCT in an existing hospital-based case-control study conducted at the University of Texas M. D. Anderson Cancer Center.

Methods: TGCT cases diagnosed between January 1990 and October 1996 (n=187) and male friend controls (n=148) matched on age, race and state of residence were enrolled in the study. Associations of marijuana use and TGCT were estimated using unconditional logistic regression adjusting for age, race, prior cryptorchidism, cigarette smoking and alcohol intake. Associations stratified on histology (seminoma, nonseminoma) were also examined.

Results: Overall, TGCT cases were more likely to be frequent marijuana users (daily or >1 day per week) than were controls [OR: 2.2, 95% CI: 1.0, 5.2]. In the analysis limited to nonseminomas, cases were significantly more likely than controls to be frequent users [OR: 3.3, 95% CI: 1.3, 8.6] and to be long-term users (10+ years) [OR: 2.3, 95% CI: 1.0, 5.8]. As the use of friend controls can bias the results of retrospective studies, we evaluated the extent to which reporting of marijuana use among the controls was consistent with data from the 1996 population-based National Survey on Drug Use and Health (NSDUH). We compared the observed number of controls who reported ever using marijuana with the expected number based on age- and race-specific proportions in the NSDUH and found no significant difference [O/E ratio: 0.96; 95% CI: 0.74, 1.22], suggesting selection or reporting bias was not an explanation for the observed associations.

Discussion: Our finding of an association between frequent marijuana use and TGCT, particularly among men with nonseminoma is consistent with the findings of a previous report. Marijuana use may be related to nonseminoma due to activation of the cannabinoid receptors during a critical time period in pubertal development; however it is also plausible that biologically active components of marijuana may function through pathways other than the endocannabinoid system. Additional studies of marijuana use and TGCT are warranted, especially studies evaluating the role of endocannabinoid signaling and cannabinoid receptors in TGCT.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr LB-394.
Abstract LB-4: Mitochondrial localized de2-7EGFR (EGFRvIII) protects glioma cells from metabolic shock
Authors: Johns Terrance G.
Published: February 2011

Thirty percent of glioma patients express an activating mutation of the epidermal growth factor receptor (EGFR) known as the de2-7EGFR (or EGFRvIII). Glioma cells expressing de2-7EGFR contain an intracellular pool of the receptor that predominantly displays high-mannose glycosylation, consistent with delayed processing. We now show in glioma cells that most of the intracellular de2-7EGFR is located in the Golgi apparatus; identifying the Golgi as the organelle where the delay arises. This intracellular analysis also revealed low-levels of the de2-7EGFR within the mitochondria. Transfection of U87MG. 2-7 cells with a constitutive active Src, or activation of the endogenous Src via integrin engagement, enhanced this mitochondrial localization. In contrast, pharmacological inhibition of Src significantly reduced mitochondrial de2-7EGFR. Since de2-7EGFR is phosphorylated by Src at Y845, we generated U87MG glioma cells expressing a de2-7EGFR with a Y845F modification. The de2-7EGFR845F failed to show mitochondrial localization even when co-expressed with constitutive active Src. Given the role of mitochondria in metabolism, the effect of low glucose on de2-7EGFR localization was examined. U87MG.de2-7EGFR glioma cells grown in low glucose displayed significantly increased levels of mitochondrial de2-7EGFR and were able to survive and proliferate in low concentrations of glucose lethal to isogenic parental cells. Finally, the presence of an active and functional pool of de2-7EGFR in the mitochondria, probably explains why this receptor is clinically-resistant to some EGFR-specific therapeutics.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr LB-4.
Abstract LB-426: Delphinidin suppresses ultraviolet B-induced cyclooxygenases-2 expression through inhibition of MAPKK4 and PI-3 kinase
Authors: Kang Nam Joo , Kwon Jung Yeon , Kim Jong-Eun , Jung Sung-Keun , Hwang Mun Kyung , Lee Hyong Joo , Lee Ki Won , Heo Yong-Seok , Bode Ann M. , Dong Zigang
Published: February 2011

Cyclooxygenase-2 (COX-2), a key mediator of inflammation, and its product, prostaglandin E2 (PGE2), enhance carcinogenesis, particularly in skin. Ultraviolet (UV) B is the most carcinogenic component of solar irradiation, and a crucial role of COX-2 in UVB-mediated skin carcinogenesis has been reported. Here, we investigated the effects of delphinidin, an abundant dietary anthocyanin, on UVB-induced COX-2 upregulation and the underlying molecular mechanism. We found that delphinidin suppressed UVB-induced COX-2 expression in JB6 P+ mouse epidermal cells. COX-2 promoter activity and PGE2 production were also suppressed by delphinidin treatment within non-cytotoxic concentrations. Activator protein-1 and nuclear factor- B, crucial transcription factors involved in COX-2 expression, were activated by UVB and delphinidin abolished this activation. UVB-induced phosphorylation of c-Jun N-terminal kinase, p38 kinase and Akt was inhibited by delphinidin. The activities of mitogenactivated protein kinase kinase (MAPKK) 4 and phosphatidylinositol-3 kinase (PI-3K) were inhibited markedly by delphinidin. A pull-down assay using delphinidin-Sepharose beads revealed that delphinidin binds directly with MAPKK4 or PI-3K in a manner that was competitive with adenosine triphosphate. Moreover, in vivo investigations using mouse skin revealed that the upregulation of COX-2 expression, MAPKK4 activity and PI-3K activity induced by UVB was abolished with delphinidin treatment. Collectively, our results demonstrated that delphinidin targets MAPKK4 and PI-3K directly to suppress COX-2 overexpression, suggesting a potential protective role for delphinidin against UVB-mediated skin carcinogenesis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr LB-426.
Abstract LB-429: Synergistic effects of low-fat diet combined with IGF-I receptor blockade on 22RV1 prostate cancer xenografts
Authors: Konijeti Ramdev , Galet Colette , Liu Bingrong , Gray Ashley , Barnard R. James , Said Jonathan , Castor Brandon , Koyama Satomi , Hwang David , Beltran Pedro , Calzone Franck , Cohen Pinchas , Aronson William J.
Published: February 2011

Introduction: IGF-I receptor (IGF-1R) blockade has previously been shown to slow prostate cancer xenograft growth. Dietary fat reduction also inhibits xenograft growth, possibly by modulation of the IGF axis. We hypothesized that a low-fat (LF) diet combined with IGF-I receptor blockade would cause additive retardation of prostate cancer growth and offset the possible untoward metabolic effects of IGF-1R antibody therapy.

Methods: Fifty severe combined immunodeficient mice were injected subcutaneously with 22RV1 cells (suppressible with IGF-1R blockade in vitro) and were randomized to four groups: 1) high-fat (HF) diet with intraperitoneal saline, 2) high-fat diet with intraperitoneal IGF-I receptor blocking antibody from Amgen: AMG479, (HFAb), 3) low-fat diet with intraperitoneal saline (LF), 4) low-fat diet with intraperitoneal AMG479, (LFAb). Treatment with either antibody or saline was initiated 10 days after tumor injection and given twice weekly, tumors were measured serially. The animals were euthanized at 19 days of treatment. Tumors were then weighed and stained for Ki67, TUNEL, and CD31. Serum levels of insulin, resistin, murine IGF-I, murine IGFBP-3, and TNF-alpha were measured.

Results: Mean tumor weights were significantly lower (by ∼ 40%) in the HFAb and LFAb group relative to the HF group. There was no difference in mean tumor weight between the HFAb and LFAb groups. Ki67 expression (% positive cells) was significantly decreased in the LFAb group compared to the HFAb group (62 + 29 vs. 94 + 4.3, p<0.001). IGF-1R antibody caused a significant increase in serum insulin levels compared to the LF and HF group, but combining the LF diet with the IGF-1R antibody significantly reduced serum insulin levels by 40% relative to the HFAb group. Likewise, combining a LF diet with the IGF-1R antibody also reduced serum TNF-alpha levels relative to the HF group.

Conclusion: IGF-1R antibody therapy inhibited xenograft growth in mice on HF and LF diets. Whereas combining a LF diet with IGF-1R antibody did not have additive growth inhibitory effects on tumor size, there was evidence of decreased tumor cell proliferation, reduced serum insulin levels and reduced pro-inflammatory cytokine levels. Further pre-clinical and clinical trials are warranted to evaluate the role of dietary interventions to enhance anti-tumor effects and offset the metabolic consequences of IGF-1R antibody therapy.

Aknowledgements: This work was supported by the NCI grant # P50CA92131 and “The Ruby Family Foundation”.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr LB-429.
Abstract LB-43: M402, a novel heparin sulphate mimetic, synergizes with gemcitabine to improve survival and reduce metastasis and epithelial-to-mesenchymal transition (EMT) in a genetically engineered mouse model for pancreatic cancer
Authors: Lolkema Martijn , Lockley Michelle , Zhou He , Duffner Jay , Kishomoto Takashi K. , Tuveson David A.
Published: February 2011

Introduction: Heparan sulphate proteoglycans (HSPGs) play a central role in tumor progression and metastasis by presenting and modulating growth factors, cytokines, and other soluble factors. A novel heparin sulphate mimetic (M402), engineered from heparin to have low anti-coagulant activity, has shown promising anti-tumor efficacy in several pre-clinical tumor models. This study was designed to probe the efficacy and mechanism of action of M402 in a genetically engineered mouse (GEM) model for pancreatic cancer.

Methods: Mice that spontaneously develop pancreatic cancer (LSL-KRASG12D/+; Trp53 LSL-R172H/flox; pdx-CRE) were treated with twice weekly i.p. doses of saline or gemcitabine (50 mg/kg) starting at Day 30, or with saline or M402 (40 mg/kg/day) administered by a subcutaneous osmotic minipump from Day 30-90, or with a combination of gemcitabine plus M402.

Results: Treatment with M402 alone did not prolong survival and gemcitabine alone showed only a modest improvement in survival; however the combination of M402 and gemcitabine significantly improved survival. Moreover, mice treated with the combination of M402 and gemcitabine showed a substantially lower incidence of metastasis. RT-qPCR analysis revealed that M402 treated mice had significantly lower levels of TGF-alpha mRNA than the saline control group, which is corroborated by a corresponding decrease in tumor cell proliferation. Immunohistochemical analysis revealed that M402 treated mice developed reduced areas of epithelial-to-mesenchymal transition (EMT), as defined by negative staining for E-Cadherin, strongly positive staining for vimentin and positive nuclear staining for SNAIL. As there is a direct link between EGFR activation and the nuclear localisation of SNAIL we propose that M402 affects gemcitabine sensitivity and metastasis formation by reducing the expression of TGF-alpha.

Discussion: M402 increased the anti-tumor efficacy of gemcitabine in a GEM model for pancreatic cancer resulting in increased survival and, interestingly, decreased incidence of metastasis. One potential mechanism is that the observed reduction in EMT may be due to the reduced expression of TGF-alpha, a cognate ligand for EGFR. These data suggest that the EGFR pathway is active in KRAS mutant tumors. Overall, these results provide a rationale for investigating the clinical use of M402 in combination with gemcitabine in the treatment of human pancreatic cancer.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr LB-43.
Abstract LB-432: Validation studies for Korean breast cancer prediction model
Authors: Park Boyoung , Lee Ji Young , Chang Myung-Chul , Noh Dong-Young , Ahn Sei-Hyun , Kang Daehee , Yoo Keun-Young , Park Sue K.
Published: February 2011

Background: A model for predicting breast cancer risk has been developed in Korea. Associated risk factors included in the model were 1st degree relatives with breast cancer, age at menarche, menopausal status, number of children, age at first fullterm pregnancy, mammography, and exercise for patients less than 50 years of age and 1st degree relatives with breast cancer, age at menarche, age at menopause, number of children, BMI, mammography, and exercise for patients greater than 50 years of age. The area under the curve among over 50 year olds was 0.655 and 0.611 among under 50 year old.

Objectives: The objective of the study was validation of an absolute risk prediction model for breast cancer in Korea by using a large, population cohort and patient registry.

Method: The Korean Multi-center Cancer Cohort (KMCC) and registry data of breast cancer patients constructed by the Korean Breast Cancer Society were used to validate the model. 12221 women more than 30 years of age at baseline answered questions about demographic characteristics, reproductive factors, lifestyle, family history since 1993 and we identified 11 and 5 incident breast cancer patient more than 50 and less than 50 years of age, respectively. Age, resident area, and included year were matched to select controls; women aged less than 50 were matched 1:20 while women aged greater than 50 were matched 1:10. In the breast cancer registry, clinical, demographic characteristics and reproductive factors of breast cancer patients were collected since 1980. We selected 2727 patients under 50 years old and 2000 patients over 50 years old matched by age and diagnostic year and calculated their 10, 20, 30, and 40 year absolute risk.

Result: In the KMCC data, 10 year absolute risk was 0.39 (95% CI 0.36-0.42) among cases and 0.36 (95% CI 0.35-0.37) among controls under 50 years old and 0.16 (95% CI 0.10-0.22) among cases and 0.08 (0.07-0.09) among controls over 50 years old and it was significantly different in the median test (P-value: 0.02 in both groups). Among breast cancer patient group over 50 years old, 10, 20, 30 and 40 year absolute risk were 0.22 (95% CI 0.21-0.23), 0.35 (95% CI 0.34-0.36), 0.43 (95% CI 0.42-0.45), 0.46 (95% CI 0.44-0.48) respectively and 0.56 (95% CI 0.55-0.57), 1.18 (95% CI 1.15-1.21), 1.53 (95% CI 1.50-1.57), 1.74 (95% CI 1.70-1.78).

Conclusion: Due to the short follow up time and small number of cancer incidence in the KMCC cohort, although absolute risk was small, a significant difference was confirmed. Future validation study with a large number and enough follow up cohort time is needed.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr LB-432.
Abstract LB-48: Non-invasive imaging of response to MEK Inhibition with AZD6244 (ARRY-142886) in a human melanoma xenograft monitored by diffusion-weighted MRI
Authors: Beloueche-Babari Mounia , Jamin Yann , Arunan Vaitha , Walker-Samuel Simon , Smith Paul D. , Waterton John C. , Halliday Jane , Workman Paul , Leach Martin O. , Robinson Simon P.
Published: February 2011

Background: Non-invasive imaging biomarkers are key to the development and evaluation of novel targeted anti-cancer drugs. The MEK inhibitor, AZD6244 (ARRY-142886), is one such agent that is now undergoing clinical testing. This drug causes inhibition of growth and induction of apoptosis in a range of pre-clinical tumor models. We therefore reasoned that such effects could translate to changes in tumor tissue cellular density that may be detectable by diffusion-weighted magnetic resonance imaging (DW-MRI). Here we test this hypothesis in a human melanoma xenograft model.

Methodology: Female nude mice bearing V600E BRAF WM266.4 melanoma sub-cutaneous xenografts (∼550 mm3 volume) were treated twice daily for 3 days by gavage with vehicle (n=9) or 75mg/kg AZD6244 (n=9). DW-MRI data were acquired pre- and 3h post the last dose, and correlated with phosphorylated (P-) ERK1/2 and the necrotic tumor fraction by histological analysis of excised tumors.

Results: Our results show that AZD6244-treated tumors were not significantly different in size compared to day 0 (100±6%) while the vehicle treated-tumors had grown by ∼ 1.4-fold (p=0.001). Relative to day 0, the mean values of the apparent diffusion coefficient (ADC), a parameter that is inversely related to tissue cellularity, were not changed in the control group (109±12%, p=0.45) but increased significantly to 160±20% (p=0.01) in the AZD6244-treated group. This effect correlated with substantially reduced P-ERK1/2 levels and increased tumor necrosis from 10± 10% in the vehicle group to 60±9% in the drug-treated group (p=0.036).

Conclusions: This study highlights changes in ADC that follow treatment with a MEK signaling inhibitor, and which precede tumor shrinkage. Our data support the use of ADC as a non-invasive pharmacodynamic biomarker for early assessment of response to AZD6244 and other therapies targeted at MEK-ERK1/2 signaling during clinical trials.

Acknowledgements: This work was funded by Cancer Research UK [CUK] project grant C1060/A6916, AstraZeneca and The Royal Society. We acknowledge the support received from the CRUK and EPSRC Cancer Imaging Centre in association with the MRC and Department of Health (England) grant C1060/A10334, also NHS funding to the NIHR Biomedical Research Centre.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr LB-48.
Abstract LB-59: Amrubicin, a third-generation synthetic anthracycline, is active in anthracycline-resistant tumors
Authors: Mamidipudi Vidya , Brady Helen , Richard Normand , Surapaneni Sekhar , Aukerman Lea S. , Heise Carla , Sung Victoria
Published: February 2011

Amrubicin, a third generation synthetic anthracycline and a potent topoisomerase (topo) II inhibitor, is approved in Japan for the treatment of lung cancer (both small-cell and non-small cell) and is being evaluated in a phase III trial in the North America and Europe for the second line treatment of SCLC. The aim of these studies was to evaluate the cross-resistance of amrubicin with other anthracyclines (doxorubicin, epirubicin) and the topo-II inhibitor etoposide, and to identify potential mechanisms of resistance to amrubicin. The doxorubicin-resistant cell lines H69-AR, MES-SA-DX5 & NCI-ADR/RES were confirmed to be resistant to doxorubicin (∼25-fold relative resistance), however, their resistance to amrubicin was low or absent (∼2-fold relative resistance). Additionally, a number of primary human ovarian and breast tumor explants that were resistant to doxorubicin and/or etoposide retained sensitivity to amrubicin. Unlike doxorubicin, amrubicin induced DNA damage, G2M cell cycle arrest and apoptosis in both doxorubicin-sensitive and -resistant lines at or below clinically relevant plasma concentrations (∼10 uM). Furthermore, in contrast to doxorubicin, fluorescence time-lapse imaging demonstrated relatively small differences in amrubicin uptake and accumulation kinetics in doxorubicin-sensitive and resistant cell lines. Using gene expression profiling studies, we showed that a greater number of genes were regulated by amrubicin than by doxorubicin in both OVCAR8 and NCI-ADR/RES lines. Amrubicin is a moderate P-glycoprotein (Pgp) substrate; however, we demonstrated that the inhibitory effect and accumulation of amrubicin is not solely modulated by Pgp in cell lines over-expressing efflux pumps including Pgp. We postulate that the high intracellular accumulation and retention of amrubicin is a result of rapid influx due to the high intrinsic permeability and lipophilic properties of amrubicin. This may explain why amrubicin overcomes pleiotropic drug resistance. In summary, we demonstrated that amrubicin has a distinct mode of action compared with other anthracyclines, is less susceptible to typical anthracycline resistance mechanisms and therefore, may be useful in the treatment of anthracycline-resistant tumors.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr LB-59.
Abstract LB-63: Expression of α+β+ splice variant of human telomerase reverse transcriptase (hTERT) in cytokeratin 19 (CK-19) positive circulating tumor cells (CTCs) of breast cancer patients
Authors: Parisi Kleo , Strati Areti , Malamos Nikolaos , Georgoulias Vassilis , Lianidou Evi
Published: February 2011

Introduction: Human telomerase reverse transcriptase (hTERT) is the catalytic subunit of telomerase. The α+β+ splice variant is the functional variant of hTERT. Circulating tumor cells (CTCs) have already been established as strong predictors of prognosis in patients with metastatic breast cancer. Our group has previously shown the prognostic significance of cytokeratin 19 (CK-19) mRNA-positive CTCs in early breast cancer. The aim of our study was to study the expression of hTERT α+β+ splice variant in CK-19 positive CTCs in breast cancer samples by qRT-PCR.

Materials and Methods: Peripheral blood (20 ml in EDTA) was obtained from 25 patients with early breast cancer before the administration of adjuvant chemotherapy, 14 patients with verified metastasis who were all tested positive for CK-19 expression by real time PCR (Stathopoulou et al, Int J Cancer 2006), and 17 female healthy volunteers. CTCs were isolated after ficoll density gradient centrifugation, following enrichment with immunomagnetic Ber-EP4 coated capture beads, mRNA was isolated using oligo (dT)25 coated magnetic beads, followed by cDNA synthesis. The expression of hTERT α+β+ splice variant was tested in both CTCs and PBMCs fractions by quantitative real-time PCR in the LightCycler, (Mavroyiannou et al, Clin Chem, 2007).

Results: hTERT α+β+ splice variant was expressed in 4/14 (29%) of CK-19 mRNA positive CTCs samples from patients with metastasis and in 5/24 (21%) of CK-19 mRNA positive CTCs samples from patients with early breast cancer. None of the 17 female healthy volunteers CTCs fraction was tested positive for hTERT α+β+ splice variant, while the corresponding PBMCs fraction was positive in all cases.

Conclusions: To our knowledge this is the first report on the expression of hTERT α+β+ splice variant in CTCs of patients with early breast cancer and verified metastasis. Further studies are needed to evaluate and confirm our findings in a larger number of patients.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr LB-63.
Abstract LB-74: A high-throughput RNAi sensitization screen of rapamycin identifies targets for rational drug combination strategies
Authors: Ou Lihui , Gehlhaus Kristen , Patel Jyoti , Chen Jinqiu , Goldsmith Paul , Mock Beverly , Caplen Natasha
Published: February 2011

RNAi screening affords an unbiased and rapid method to identify genes involved in particular cellular processes and is thus a powerful tool for drug target identification and validation. Rapamycin is a well defined inhibitor of mTOR, a protein being actively pursued as an anti-tumor target. In breast cancer patients, however, treatment with mTOR inhibitors has shown only modest activity suggesting that a combined approach may be required to maximize the clinical application of mTOR inhibitors in these patients. In this study, we performed a high-throughput synthetic siRNA-based RNAi screen of the human kinome plus 350 additional genes (4 siRNAs per gene) in combination with rapamycin, to identify candidate genes whose silencing potentiate the inhibitory effects of rapamycin. Screens were conducted in the ER+ breast cancer cell line MCF-7 and the triple negative breast cancer cell line MDA-MB-468. For the RNAi screen rapamycin (10 nM) or vehicle only (0.1% DMSO) was added 48 hours post siRNA transfection and cell viability was measured after a further 24 hours of incubation. By comparing the normalized effect on cell viability for each siRNA (Z-score) in the control and rapamycin screens we identified 36 candidate genes whose silencing sensitized MCF-7 cells to rapamycin and 56 that sensitized MDA-MB-468 cells. The silencing of six candidate genes sensitized both cell lines to rapamycin, AKT1, ASPA, CDKN2A, MAP3K7IP1, MAPK12 and PCTK3. The sensitization of rapamycin by silencing of AKT1 was confirmed. Rapamycin treatment increased AKT phosphorylation in the cell lines. HDAC inhibitors have been shown to facilitate the dephosphorylation of AKT; therefore, we tested the combination of rapamycin with the HDAC inhibitor MS-275. MS-275 completely blocks rapamycin-induced AKT phosphorylation, and combining it with rapamycin synergistically inhibited the growth of the MCF-7, MDA-MB-468, MDA-MB-435 and MDA-MB-231 breast cancer cell lines. We investigated if other pathways are affected by combining rapamycin with MS-275. De-regulation of the RAF-MEK-ERK pathway is frequently detected in human cancers but the high level of ERK phosphorylation is significantly reduced in cells treated with the rapamycin/MS-275 combination. To profile the unphosphorylated, mono and dual-phosphorylated isoforms of ERK1 and ERK2 we used a capillary isoelectric focusing immunoassay to show that the di-phosphorylated isoform of ERK2 was decreased. Our results highlight the potential of high-throughput siRNA screens to identify rational drug combination strategies.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr LB-74.
Abstract LB-76: A study of neoadjuvant bevacizumab with standard chemoradiation versus chemoradiation alone in locally advanced rectal cancer
Authors: Willett Christopher G. , Duda Dan G. , Ancukiewicz Marek , Shah Mira , Czito Brian , Bentley Rex , Poleski Martin , Fujita Hiroshi , Lauwers Gregory Y. , Carroll Madeline , Tyler Douglas , Mantyh Christopher , Shellito Paul , Chung Daniel C. , Clark Jeffrey W. , Jain Rakesh K.
Published: February 2011

The anti-vascular endothelial growth factor (VEGF) antibody bevacizumab is increasingly being tested with pre-operative (neoadjuvant) regimens in patients with localized cancer, but its effects on metastasis and survival remain unknown.

This study examined the outcome of clinical stage II/III rectal cancer patients treated on a prospective phase II study of bevacizumab based chemoradiation and surgery to a contemporarily treated group of patients with standard chemoradiation and surgery at the same institution (Duke University Medical Center). Outcome analyses were performed on: 1. thirty-two patients treated prospectively from 2002 to 2008 with neoadjuvant bevacizumab, 5-fluorouracil and radiation therapy and surgery; versus 2. forty-two patients treated from 2004 to 2008 with capecitabine, radiation therapy and surgery. The current median follow-up is 3 years. While local control was 100% in both groups (i.e., there was no local recurrence), the patients treated with bevacizumab-based chemoradiation and surgery showed statistically significantly higher overall survival rates and a trend higher disease-free survival rates than patients treated with chemoradiation alone and surgery. No statistically significant differences were observed in local control or toxicity between the two groups.

These data indicate that adding bevacizumab to neoadjuvant chemoradiation compares favorably to chemoradiation alone in a contemporary population of rectal cancer patients. The efficacy of neoadjuvant bevacizumab will have to be established prospectively in randomized studies, but bevacizumab with standard chemoradiation and surgery shows promising safety profiles and does not appear to increase metastasis after three years in locally advanced rectal cancer patients. This study was partially supported by NIH grants R21-CA99237, P01-CA80124, R01-CA115767, R01-CA85140, R01-CA126642 and Federal Share/NCI Proton Beam Program Income grants, and by the National Foundation for Cancer Research.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr LB-76.
Abstract LB-92: Loss of a single Hic1 allele accelerates polyp formation in Apc mice
Authors: Mohammad Helai , Zhang Wei , Selonick Helen , Leadem Benjamin , Zhang Minsi , Hooker Craig , Watkins David N. , Karim Baktiar , Huso David , Herman James G. , Baylin Stephen B.
Published: February 2011

Mutations in the Adenomatous Polyposis Colt (APC) gene have been implicated both in familial as well as sporadic gastrointestinal (GI) cancers. APC mutations are associated with autosomal dominant inheritance of disease in humans. Similarly, mice that contain a single mutant APC gene encoding a protein truncated at aa 716 (Ape716) develop multiple polyps throughout the GI tract as early as 4 weeks after birth. Inactivation of another tumor suppressor gene, Hypermethylated in Cancer 1 (HIC1) often occurs in human cancers, including GI, via CpG island hypermethylation. Homozygous deletion of Hic1 in mice results in major developmental defects and embryonic lethality. Hic1 heterozygotes have previously been shown to develop age dependent tumors of a variety of tissue types. We now report that loss of a single Hic1 allele can promote crypt dysplasia of the small intestine and further potentiate polyp formation in Apc716 mice. Hic1+/−, Apc716 double heterozygous mice develop increased numbers of polyps throughout the GI tract by 60 days. Hic1 expression is lost in polyps with a selective increase in DNA hypermethylation of this gene only in polyps from double-heterozygous mice. Immunohistochemical analyses of polyps show increases in markers such as -catenin, SIRT1, and Sox9, indicating aberrant Wnt and Hic1 signaling. Together, our data suggest that loss of a gene frequently silenced via epigenetic mechanisms, Hic1, can cooperate with loss of a gene often mutated in GI cancer, Apc, to promote tumorigenesis in an in-vivo model of multiple intestinal neoplasia.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr LB-92.
Helicobacter pylori Therapy in Children: A Focus on Proton Pump Inhibitors
Authors: Chiesa Claudio , Anania Caterina , Pacifico Lucia , Olivero Giuseppe , Osborn John F.
Published: February 2011

Over the last two decades, there have been many studies on children who have sought an effective and safe treatment to eradicate Helicobacter pylori infection, but as yet, no therapy regimen has been found which is always effective and safe. Differences in drug response among pediatric patients are common. Such individual variability in drug response is multifactorial, including environmental, genetic, development and disease determinants that affect the disposition of a given drug. In pediatric efficacy studies for the management of H. pylori eradication in children, the most commonly tested regimen has contained a combination of proton pump inhibitor (PPI), clarithromycin and amoxicillin, followed by triple therapies containing PPI, clarithromycin and nitroimidazoles. Thus, PPIs are an integral part of triple therapy for H. pylori eradication in children with gastroduodenal disease. In this article, we comprehensively review, from a pediatric point of view, the literature on the clinical, pharmacologic and microbiologic properties of PPIs. We also discuss genetic, developmental and other host-related factors that may affect the efficacy of these drugs. Finally, we provide some guidance regarding their potential role and limitations for H. pylori eradication in children.
Efflux Pump Overexpression in Conjunction with Alternation of Outer Membrane Protein May Induce Acinetobacter baumannii Resistant to Imipenem
Authors: Luo LiuLin , Jiang XiaoFei , Wu Qiong , Wei LiMing , Li JianHua , Ying ChunMei
Published: February 2011

Background: To investigate the role of outer membrane proteins in Acinetobacter baumannii resistant to imipenem, 2 strains were procured from the same patient. Methods: The imipenem-resistant strain was obtained following a period of imipenem treatment in vivo. The multilocus sequence typing and repetitive extragenic palindromic PCR results indicated that the imipenem-resistant strain originated from the sensitive one. Results: Isoelectric focusing detected no carbapenemases, with neither OXA carbapenemases nor metallo-β-lactamases found. Mass spectrophotometric analysis revealed that 3 outer membrane proteins were expressed differentially in the 2 strains: 2 downregulated proteins (OprD and CarO) and 1 upregulated the 34-kDa efflux pump protein in the resistant strain. A 32-fold decrease in the MIC for imipenem in the presence of Phe-Arg-β-naphthylamide in the same strain indicated a possible involvement of the efflux pump mechanism in its resistance, which was consistent with the findings that the mRNA expression of the 34-kDa efflux pump gene was almost fivefold upregulated in the imipenem-resistant strain compared with that in the imipenem-sensitive strain. Such a significant difference, however, was not found in the expression of AdeB and AdeJ between the 2 strains, and AdeE was not detected. Conclusions: Our results suggested that downregulation of outer membrane proteins in conjunction with efflux pump overexpression might contribute to imipenem resistance induced in vivo in A. baumannii.
Mitral Regurgitation due to Papillary Muscle Dyssynchrony during Trastuzumab Treatment
Authors: Karabay Can Yucel , Kocabay Gonenc , Kalayci Arzu , Zehir Regaip , Tanboga Halil
Published: February 2011

Trastuzumab is a monoclonal antibody used for the treatment of metastatic breast carcinoma in women whose tumors overexpress the human epidermal growth factor receptor-2. Although trastuzumab is generally well tolerated, cardiac toxicity has occurred as a rare but potentially serious complication that limits its use in some patients. In this study, we detected new-onset mitral regurgitation in trastuzumab-treated patients. To our knowledge, there is no report or survey on new-onset mitral regurgitation during this treatment. We discussed the possible reasons for this newly described side effect of the drug in the light of left ventricular longitudinal global strain and papillary muscle dyssynchrony of the patient by detecting two-dimensional speckle tracking echocardiography.
Intravenous Thrombolysis Based on Diffusion-Weighted Imaging and Fluid-Attenuated Inversion Recovery Mismatch in Acute Stroke Patients with Unknown Onset Time
Authors: Aoki Junya , Kimura Kazumi , Iguchi Yasuyuki , Shibazaki Kensaku , Iwanaga Takeshi , Watanabe Masao , Kobayashi Kazuto , Sakai Kenichiro , Sakamoto Yuki
Published: February 2011

Background and Purpose: Patients with unknown onset time would be able to receive intravenous thrombolysis when showing diffusion-weighted imaging (DWI)/fluid-attenuated inversion recovery (FLAIR) mismatch. Methods: Consecutive acute stroke patients with unknown onset time were prospectively enrolled. We defined patients as having unknown onset time when the last known normal time (LNT) was not consistent with the first found abnormal time (FAT). Only patients with anterior-circulation stroke and presence of arterial lesion were enrolled. Intravenous thrombolysis was conducted within 3 h from FAT if the patient showed DWI/FLAIR mismatch. Results: From June 2009 to May 2010, 10 patients [median age, 84 years (interquartile range, IQR, 64–90); National Institutes of Health Stroke Scale (NIHSS) score, 14 (IQR, 9–19)] were enrolled. Subjects included 4 patients who developed stroke during sleep, 5 with disturbance of consciousness, and 1 with aphasia. Median interval between LNT and thrombolysis was 5.6 h (IQR, 4.5–9.8) and median interval between FAT and thrombolysis was 2.5 h (IQR, 2.1–2.8). Three patients had internal carotid artery occlusion, 5 had M1 occlusion, and 2 had M2 occlusion. Early recanalization within 24 h was seen in 7 patients (complete recanalization, n = 4; partial recanalization, n = 3). No patients experienced symptomatic cerebral hemorrhage within 48 h. At day 7, 5 patients showed dramatic recovery (defined as ≧10-point reduction in total NIHSS score or score of 0 or 1). At 3 months, favorable outcome (modified Rankin scale score, 0–2) was seen in 4 patients. Conclusion: Acute stroke patients with DWI/FLAIR mismatch may be able to safely receive intravenous thrombolysis.
Effect of Galla Chinensis on Growth and Metabolism of Microcosm Biofilms
Authors: Cheng L. , Exterkate R.A.M. , Zhou X. , Li J. , ten Cate J.M.
Published: February 2011

Galla chinensis extract (GCE) interferes with de- and remineralization of dental enamel and the growth and metabolism in planktonic bacteria. However, no information is available on GCE effects on biofilms formed with saliva as inoculum. The aim of the current experiments was to investigate the effects of GCE at different stages of salivary microcosm biofilm formation. Biofilms formed on glass or enamel surfaces were treated with GCE solutions at different concentrations and at different time points. Effects were assessed by lactic acid formation and colony-forming unit (CFU) counts of the biofilms. The results showed that GCE treatments inhibited growth and acid metabolism of both nascent and mature microcosm biofilms. Pretreatment of the substratum with GCE solutions inhibited growth and lactic acid production of biofilms grown on enamel, but had little effects on biofilms formed on glass surfaces. A maximum GCE effect was found when biofilms, on either surface type, were treated after 8 h of formation with 40 h of subsequent growth. In medium with sucrose-fermenting biofilms, low concentrations of GCE (0.2 and 0.1 mg/ml) inhibited acid production without killing bacteria of the biofilm. Differences were found in GCE effects on biofilms formed with saliva from different donors, with reductions in acid formation and CFU values ranging between 0 and 78%. In conclusion, bioactive components in GCE reduce or inhibit both growth and lactic acid formation in biofilms.
Do Bicarbonate-Based Solutions for Continuous Renal Replacement Therapy Offer Better Control of Metabolic Acidosis than Lactate-Containing Fluids?
Authors: Agarwal B. , Kovari F. , Saha R. , Shaw S. , Davenport A.
Published: February 2011

Introduction: Evidence that bicarbonate haemofiltration and dialysate fluids are superior to lactate in patients with acute kidney injury treated by continuous renal replacement therapy (CRRT) remains controversial. Methods: We prospectively audited acid-base during the first 48 h of CRRT in 62 patients, using bicarbonate and lactate fluids. Results: Baseline lactate was greater in the bicarbonate group (4.76 ± 0.77 vs. 2.92 ± 0.5 mmol/l, p < 0.01), but pH, bicarbonate, chloride and base excess were similar. Lactate fell significantly in the bicarbonate group to 2.88 ± 0.3 mmol/l at 24 h and 2.39 ± 0.2 mmol/l at 48 h, but not in the lactate group. Base excess improved more with bicarbonate, median increase in the first 24 h was 51.6% (29.1–96.9) versus 18.5% (–5 to 55) with lactate and 74.2% (38.5–123) versus 36.1% (–3.6 to 68), p < 0.05 at 48 h. However, there were no significant differences in bicarbonate, chloride, pH, blood pressure and vasopressor requirements. 13.3% of patients were switched from lactate to bicarbonate fluids due to failure to correct acidosis. Subgroup analysis of 19 patients with liver failure showed similar results. Conclusion: Bicarbonate fluids led to a more rapid fall in lactate and greater improvement in base excess during CRRT, but not overall control of acidosis.
Suppression of Endothelial P-Selectin Expression Contributes to Reduced Cell Trafficking in Females
Authors: Villar Inmaculada C. , Scotland Ramona S. , Khambata Rayomand S. , Chan Melissa , Duchene Johan , Sampaio Andre L. , Perretti Mauro , Hobbs Adrian J. , Ahluwalia Amrita
Published: February 2011

Objective—

Sex hormones underlie the lower incidence of cardiovascular disease in premenopausal women. Vascular inflammation is involved in the pathogenesis of several cardiovascular diseases and it has been reported that sex hormones modulate inflammatory responses but mechanisms responsible for these effects are not yet fully established. Herein, we assessed whether sex differences in leukocyte recruitment might exist and investigated the underlying mechanisms involved in this response.

Methods and Results—

Treatment with interleukin-1β (IL-1β) or tumor necrosis factor-α caused leukocyte rolling, adhesion, and emigration in mesenteric postcapillary venules in vivo that was substantially reduced in female mice compared with male mice; this difference was abolished by ovariectomy and partially restored by estrogen replacement. Deletion of endothelial nitric oxide (NO) synthase or cyclooxygenase-1 alone or in combination did not alter the leukocyte recruitment in IL-1β-treated females but significantly enhanced this response in male mice. Treatment of murine pulmonary endothelial cells with IL-1β increased expression of P-selectin in male but not female cells.

Conclusion—

We have demonstrated a profound estrogen-dependent and NO and prostacyclin-independent suppression of leukocyte recruitment in females.
Body Mass Index and Adverse Cardiovascular Outcomes in Heart Failure Patients With Preserved Ejection Fraction
Authors: Haass Markus , Kitzman Dalane W. , Anand Inder S. , Miller Alan , Zile Michael R. , Massie Barry M. , Carson Peter E.
Published: February 2011

Background—

Obesity is a major risk factor for incident heart failure (HF). Paradoxically, in HF with reduced left ventricular ejection fraction (HFREF), a high body mass index (BMI) appears to be beneficial. Approximately 50% of HF patients have a preserved left ventricular ejection fraction (HFPEF). However, there are few data regarding the relationship between BMI and outcomes in HFPEF.

Methods and Results—

Baseline characteristics and cardiovascular outcomes were assessed in the 4109 patients (mean age, 72 years; mean follow-up, 49.5 months) in the Irbesartan in HF with Preserved Ejection Fraction (I-PRESERVE) trial. Based on the BMI distribution, 5 BMI categories were defined: <23.5, 23.5 to 26.4, 26.5 to 30.9, 31 to 34.9, and ≥35 kg/m
2
. Most patients (71%) had a BMI ≥26.5, 21% had a BMI between 23.5 and 26.4, and 8% had a BMI <23.5 kg/m
2
. Patients with higher BMI were younger, more often women, and more likely to have hypertension and diabetes and higher left ventricular ejection fraction. Patients with BMI of 26.5 to 30.9 kg/m
2
had the lowest rate for the primary composite outcome (death or cardiovascular hospitalization) and were used as reference group. After adjustment for 21 risk variables including age, sex, and N-terminal pro-brain natriuretic peptide, the hazard ratio for the primary outcome was increased in patients with BMI <23.5 (hazard ratio, 1.27; 95% confidence interval, 1.04 to 1.56;
P
=0.019) and in those with BMI ≥35 kg/m
2
(hazard ratio, 1.27; 95% confidence interval, 1.06 to 1.52;
P
=0.011) compared with the referent group. A similar relationship was found for all-cause mortality and for HF hospitalization.

Conclusions—

Obesity is common in HFPEF patients and is accompanied by multiple differences in clinical characteristics. Independent of other key prognostic variables, there was a U-shaped relationship, with the greatest rate of adverse outcomes in the lowest and highest BMI categories.

Clinical Trial Registration—

URL:
http://www.clinicaltrials.gov
. Unique identifier: NCT000095238.
Cartilage Oligomeric Matrix Protein Inhibits Vascular Smooth Muscle Calcification by Interacting With Bone Morphogenetic Protein-2
Authors: Du Yaoyao , Wang Yue , Wang Li , Liu Bo , Tian Qingyun , Liu Chuan-ju , Zhang Tao , Xu Qingbo , Zhu Yi , Ake Oldberg , Qi Yongfen , Tang Chaochu , Kong Wei , Wang Xian
Published: February 2011

Rationale:

Vascular calcification is a significant contributor to cardiovascular morbidity and mortality. We recently reported that cartilage oligomeric matrix protein (COMP) is pivotal for maintaining the homeostasis of vascular smooth muscle cells (VSMCs). Whether COMP affects the process of vascular calcification is unknown.

Objective:

We aimed to test whether COMP modulates vascular calcification.

Methods and Results:

VSMC calcification in vitro was induced by calcifying media containing high inorganic phosphate or calcium. In vivo medial vessel calcification was induced in rats by 5/6 nephrectomy with a high-phosphate diet or by periadventitial application of CaCl
2
to the abdominal aorta. COMP protein level was markedly reduced in both calcified VSMCs and arteries. COMP deficiency remarkably exacerbated VSMC calcification, whereas ectopic expression of COMP greatly reduced calcification. Furthermore, COMP knockdown facilitated osteogenic markers expression by VSMCs even in the absence of calcifying media. By contrast, COMP overexpression significantly inhibited high phosphate– or high calcium–induced VSMC osteochondrogenic transition. Induction of osteogenic marker expression by COMP silencing was reversed by a soluble form of bone morphogenetic protein (BMP)-2 receptor IA, which suggests a BMP-2–dependent mechanism. Our data revealed that COMP bound directly to BMP-2 through the C terminus, inhibited BMP-2 receptor binding, and blocked BMP-2 osteogenic signaling, indicating COMP inhibits osteochondrogenic transition of VSMCs at least partially through inhibiting BMP-2.

Conclusions:

Our data strongly suggest that COMP is a novel inhibitor of vascular calcification. The imbalance between the effects of COMP and BMP-2 may provide new insights into the pathophysiology of vascular calcification.