bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1378: Concurrent inhibition of c-Met and VEGF signaling suppresses tumor invasion in orthotopic Panc-1 pancreatic carcinomas in mice
Authors: Sennino Barbara , Williamson Casey W. , Bhagwandin Vikash , Christensen James G. , McDonald Donald M.
Published: August 2012

Multiple factors can contribute to evasive resistance that develops during treatment with angiogenesis inhibitors that target the vascular endothelial growth factor (VEGF) pathway. Evidence from studies of neuroendocrine tumors in RIP-Tag2 transgenic mice indicates that hypoxia-induced activation of pro-invasive pathways involving the receptor for hepatocyte growth factor, c-Met, can participate. The present study sought to determine whether this mechanism also applies to other types of tumors. Our approach was to ask whether growth and invasiveness of Panc-1 pancreatic adenocarcinomas implanted orthotopically in nude mice were reduced by inhibition of c-Met during concurrent treatment with an angiogenesis inhibitor for 3 weeks. Panc-1 tumors in mice treated with the angiogenesis inhibitor sunitinib, a tyrosine kinase inhibitor that blocks VEGFR and related receptors, had a 75% reduction in vascularity and grew more slowly than controls but had twice as much of intratumoral hypoxia, assessed by pimonidazole staining. Unlike the faint c-Met immunoreactivity in most tumor cells of vehicle-treated Panc-1 tumors, c-Met staining was stronger in tumor cells after treatment with sunitinib. Tumors in mice treated with the selective c-Met inhibitor PF-04217903 alone had little change in tumor vascularity or intratumoral hypoxia and grew faster than those treated with sunitinib. However, tumors treated with sunitinib plus PF-04217903 together grew more slowly than after sunitinib alone but had similar amounts of vascular pruning and hypoxia. Tumor invasiveness, reflected by amylase-positive acinar cells of the exocrine pancreas located within tumors, was exaggerated after sunitinib treatment but, importantly, was significantly less in tumors treated with sunitinib plus PF-04217903. These findings indicate that sunitinib used alone reduced the growth of Panc-1 tumors but increased intratumoral hypoxia, c-Met expression, and local invasion into the surrounding normal pancreas. By comparison, sunitinib administered concurrently with the c-Met inhibitor PF-04217903 resulted in further slowing of tumor growth and less tumor invasiveness.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1378. doi:1538-7445.AM2012-1378
Abstract 1394: Acute bacterial infection increases lung cancer metastasis via toll-like receptors 2 and 4
Authors: Chow Simon C. , Chan Carlos HF , Rousseau Mathieu C. , Cools-Lartigue Jonathan , Roussel Lucie , Giannias Betty , Yoon Heewon , Chen Crystal , Ferri Lorenzo E.
Published: August 2012

INTRODUCTION: Surgery is required for curative treatment of lung cancer but is associated with a high rate of bacterial infections such as pneumonia. There is emerging clinical evidence to suggest that infectious complications may decrease survival after cancer surgery, but the mechanism is unclear. Interactions between bacteria and host cells are mediated by specialized pathogen recognition receptors, of which the Toll-like receptors (TLRs) are best characterized. We and others have shown that cancer cells express TLRs, but their function is largely unknown. The aim of this study is to investigate the mechanisms of bacterial infection-facilitated lung cancer metastasis with a particular focus on the role of TLRs. METHODS: Two lung cancer cell lines (murine H-59 and human A549) were incubated a) directly with heat-inactivated bacteria (S.pneumonia or E.coli) or purified bacterial antigens (lipopolysaccharide or lipoteichoic acid), or b) indirectly with an in vitro pneumonia model using conditioned media from pulmonary bronchial epithelial cells incubated with heat-inactivated bacteria or bacterial antigens. Migratory and metastatic ability of thus treated cells were determined in vitro (adhesion, migration) and in vivo (hepatic intravital microscopy and intra-splenic liver metastasis). A clinically relevant in vivo model of severe infection, cecal ligation and puncture (CLP) or sham control, was employed in some animals. To assess the role of TLRs, we used transgenic TLR4 knockout mice, and small molecule inhibiting molecules or antibodies of TLRs. RESULTS: Direct and indirect (in vitro pneumonia) infection of H-59 and A549 increased adhesion to extracellular matrix components approximately 2-8 fold and 2-4 fold over negative control, respectively. In vitro pneumonia increased in vitro migration of H-59 approximately 2-5 fold. Direct and indirect incubation of H-59 with S.pneumonia and E.coli increased the in vivo adhesion to liver sinusoids 2-4 fold. CLP (in vivo infection model) enhanced the in vivo adhesion of H-59 3-fold and increased number of liver metastases at 2 weeks post-injection approximately 12 fold. These effects were attenuated in TLR4 -/- mice and with TLR2 and TLR4 inhibition. CONCLUSION: Activation of TLR2 or TLR4 on lung cancer cells, either directly by S.pneumonia and E.coli, indirectly though activated bronchial epithelial cells, or via an in vivo infection, increases cancer cell adhesion, migration and metastasis. TLRs thus represent a potential therapeutic target in bacterial infection facilitated cancer metastasis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1394. doi:1538-7445.AM2012-1394
Abstract 140: microRNA regulation of cell viability and drug response in cancer
Authors: Du Liqin , DeSevo Christopher , Borkowski Robert , Baker Michael , Wistuba Ignacio , Minna John , Pertsemlidis Alexander
Published: August 2012

Lung cancer is the leading cause of cancer-related deaths, with the majority of deaths due to failed therapy from tumor drug resistance. Third-generation chemotherapeutic agents represent the standard first-line treatment for advanced small cell (SCLC) and non-small cell (NSCLC) lung cancer patients. Response rates are poor (20-40%) with a median survival of 8-10 months. In an unbiased and comprehensive approach, we have combined a high-throughput screening platform with a library of chemically synthesized microRNA mimics and inhibitors. We have used this platform to identify mimics and inhibitors that reduce cell viability in general, and those that specifically sensitize cells to taxanes. We have identified several miRNAs for which over-expression or inhibition has a dramatic and selective effect on cell viability or drug response. We have demonstrated that miR-337-3p mimic sensitizes NSCLC cells to taxanes. By combining in vitro and in silico approaches, we identified STAT3 and RAP1A as direct targets that mediate the effect of miR-337-3p by enhancing taxane-induced arrest in the G2 phase of the cell cycle. We have identified an inhibitor of miR-139-5p as a potent and selective regulator of SCLC cell viability. Inhibiting miR-139-5p decreases SCLC cell viability by over 80%, but has a minimal cytotoxic effect on that of NSCLCs or immortalized human bronchial epithelial cells. We are currently investigating the targets of miR-139-5p that mediate its effect on SCLC cell viability. We also identified miR-10a inhibitor as increasing cell viability, with the converse observed for miR-10a mimic, suggesting that miR-10a acts as a tumor suppressor gene by directly decreasing expression of gene(s) that promote cell survival and growth. Manipulation of miR-10a levels also resulted in significant changes in both mRNA and protein levels of its predicted target, the catalytic subunit of phosphatidylinositol 3-kinase (PI3K), which has been shown to play a major role in proliferation and survival in a number of human cancers and is a significant therapeutic target. We have identified miR-337-3p as a regulator of taxane sensitivity, and miR-10a and miR-139-5p as modulators of cell viability. Increasing levels of miR-337-3p and inhibiting miR-10a and miR-139-5p may therefore provide novel therapeutic tools for the treatment of NSCLC and SCLC.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 140. doi:1538-7445.AM2012-140
Abstract 1403: Multiorogan metastasis of human HER-2+ breast cancer in immunodeficient mice
Authors: Lollini Pier-Luigi , Nicoletti Giordano , Ianzano Marianna , Croci Stefania , Grosso Valentina , Palladini Arianna , Iezzi Manuela , Landuzzi Lorena , Giovanni Carla De , Nanni Patrizia
Published: August 2012

Metastatic spread is the major cause of morbidity and death among cancer patients. In vivo studies of the metastatic process are severely hampered by the fact that most human tumor cell lines derived from highly metastatic tumors, such as human HER-2+ breast cancer, fail to consistently metastasize in immunodeficient mice like athymic nude mice. We studied whether a highly immunodeficient double knockout mouse, Rag2−/−;Il2rg−/−, which lacks T, B and NK cell activity, was more permissive to metastatic spread than the nude mouse. Metastatic dissemination in Rag2−/−;Il2rg−/− mice was widespread, and reached all sites commonly affected in human patients, including lungs, liver, bones and brain. Interestingly, metastatic spread from local tumors was only marginally different between tumors growing orthotopically or subcutaneously, both for what concerned the more malignant MDA-MB-453 cell line and the less malignant BT-474. Intravenous administration of cells significantly enhanced the metastatic spread of BT-474 cells, with the proportion of affected mice attaining 100%. Different metastatic burdens were observed in different organs, and the use of EGFP-tagged cells was instrumental in allowing a precise detection of metastatic deposits in bones, liver and brain. Quantitative evaluation of metastatic spread in Rag2−/−;Il2rg−/- mice was not limited to EGFP detection, for example we used qPCR with human-specific primers to quantitate metastatic burden in the brain, and flow cytometry to detect HER-2-positive disseminated tumor cells in the bone marrow. The brain is a common site of metastatic spread, but tumor growth in immunodeficient mice fails to reproduce this fateful property of human tumors, unless unique cell lines, selected variants and/or special injection routes are used. In contrast, spontaneous brain metastases from local tumors were common in Rag2−/−;Il2rg−/- mice, and their frequency reached 100% after intravenous injection. Morphologic analysis of brain deposits showed that multiple metastases were present, both intracerebral and intraventricular or leptomeningeal, ranging from minimal deposits of few cells to huge masses. In conclusion, human HER-2+ human breast cancer cells in Rag2−/−;Il2rg−/− mice faithfully reproduce the multiorgan metastatic pattern observed in patients, thus allowing the investigation of metastatic mechanisms and the preclinical study of novel antimetastatic agents.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1403. doi:1538-7445.AM2012-1403
Abstract 141: Epigenetic silencing of miR-122 in hepatocellular carcinoma
Authors: Song Kyoungsub , Han Chang , Wu Tong
Published: August 2012

It has been reported that miRNAs potently influence cellular function through the regulation of extensive gene expression networks and most tumors are characterized by globally diminished miRNA expression. However, the potential mechanism of microRNA expression change in tumorigenesis remains to be further investigated. In this study, we focus on the epigenetic regulation of miRNA expression in hepatocellular carcinoma. We first performed miRNA microarray analysis in HepG2 cells, which reveals significant changes in miRNA expression profiling with 23 upregulated miRNAs and 15 downregulated miRNAs induced by the treatment with 5′aza-2′deoxycytidine (5′-aza, DNA methylation inhibitor) and 4-phenylbutyric acid (PBA, histone deaceltylation inhibitor). Interestingly, miR-122, the most abundant miRNA in the liver, is upregulated by 5′-aza and PBA, which is validated by qRT-PCR analysis in both HepG2 and Huh7 cells. In addition, miR-122 expression is increased by the overexpression of PPARγ or the treatment of PPARγ agonist (15-keto PGE2 or 15d-PGJ2).We then demonstrate that peroxisome proliferator-activated receptor gamma (PPARγ) and retinoid X receptor alpha (RXRα) bind to conserved DR-1 and DR-2 (peroxisome proliferator-activated response element) in the miR-122 promoter region and these bindings are significantly increased by 5′-aza and PBA with the biotinylated oligonicleotides precipitation assay. However, 5′-aza and PBA inhibit the binding of N-CoR (nuclear receptor corepressor) or SMRT (silencing mediator for retinoid and thyroid hormone receptor) to DR-1 or DR-2. And we found that 5′-aza and PBA inhibit PPARγ/N-CoR/SMRT protein complex formation in HepG2 cells with the immunoprecipitation assay. Furthermore, we observe that SUV39H1(H3K9 methyl transferase) protein is decreased by the co-treatment of 5′aza and PBA; and the suppression of endogenous SUV39H1 expression with SUV39H1siRNA increases miR-122 expression. Taken together, our results suggest that histone acethylation and demethylation lead to the release of PPAR-gamma from PPAR-gamma/N-CoR/SMRT protein complex to activate miR-122 transcription and to the inhibition SUV39H1 protein expression for the elimination of histone methylation to further facilitate miR-122 transcription. In conclusion, Epigenetic silencing is one of the most important mechanisms for diminished miR122 expression in hepatic carcinogenesis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 141. doi:1538-7445.AM2012-141
Abstract 1569: Multivalent melanoma vaccine using primary human melanoma cells and a vaccinia virus based antigen retrieval system
Authors: Suriano Robert , Rajoria Shilpi , George Andrea , Jussim Casey , Shanmugam Arulkumaran , Geliebter Jan , Tiwari Raj K. , Wallack Marc K.
Published: August 2012

Melanoma is the fifth most diagnosed cancer in men and seventh most diagnosed cancer in women and it is estimated that there will be over 70,000 new cases and 8,000 deaths in 2011. Prevention of both primary and secondary melanomas requires the development of a melanoma specific multi-valent vaccine. We have been involved in developing a vaccinia virus based vaccine consisting of melanoma cell membrane antigens and integrated vaccinia viral proteins, which serve as a potent adjuvant. This melanoma vaccine, referred to as viral membrane oncolysate (VMO), is composed of five primary cell lines derived from patient tumors each independently infected with vaccinia virus and has been shown to induce anti-cancer immune response in clinical trials. Notable results were obtained in node positive subsets of patients that showed a positive response in survival distribution function suggesting that this preparation is an active therapeutic immunogen but the mechanism of immune activation needs to be elucidated. In order for us to define the immunogens that impart the clinical efficacy of the this melanoma VMO vaccine, it is essential to characterize the primary cell lines with respect to their phenotypic characteristics as well as to define the melanoma antigen repertoire so that effective vaccine strategies can be designed that do not rely exclusively on tumor derived primary cells. Our study reveals that all the five primary cell lines expressed antigens, such as gp100, CD146, and tyrosinase, similar to several commercially available melanoma cell lines although at varying concentrations. In addition, the five primary cell lines demonstrated varying migratory/invasive properties using a Boyden Chamber assay and their tumorigenic potential is being tested in nude mice. The cells were also characterized with respect to BRAF mutations. We observed several similarities between the antigenic profile of the primary and established cell lines as well as some unique characteristics. We conclude that using a combination of defined antigens from primary tumor cells is useful in designing a pan-antigen immunotherapeutic vaccine. This melanoma pan antigen vaccine can be an effective tool in primary prevention of melanoma presumably having the highest clinical efficacy when combined with unique antigens from primary cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1569. doi:1538-7445.AM2012-1569
Abstract 1576: An oral therapeutic vaccine for colorectal cancer effectively eradicates intestinal tumors independently of target tumor-antigen specific immunities in APCMin/+ hCEA mice
Authors: Zhong Zhenyu , Zhai Yougang , Qiao Liang
Published: August 2012

Colorectal cancer is among the leading cause of cancer-related death in patients worldwide, and the requirement of an effective vaccine is urgent. Here, we designed a pseudovirus-based therapeutic vaccine for colorectal cancer, which is comprised of a plasmid encoding a colorectal tumor-associated antigen (human CEA) packaged inside the bovine papillomavirus like particles (VLP-CEA vaccine). Oral immunization of APCMin/+ hCEA mice (a mouse model of human colorectal cancer) with VLP-CEA vaccine greatly reduced the tumor number compared with those received PBS. More importantly, the APCMin/+ hCEA mice that received pseudovirus vaccine had dramatically enhanced survival rates than those only received PBS. Surprisingly, CEA-specific adaptive immunities are dispensible for tumor elimination as similar tumor number reductions are seen in the APCMin/+ or APCMin/+ hCEA mice that are immunized with either VLP-CEA or VLP-GFP (VLPs packaging a GFP-containing plasmid). Consistently, we found that CTL responses are not required for tumor eradication since depleting CD8 T cells prior to vaccinations didn't impair the vaccine efficacy. Finally, we found that VLP-CEA and VLP-GFP are both able to activate the inflammasome which might directly induce tumor cell death. Thus, our data indicate that independent of the target tumor-antigen specific adaptive immunity, our pseudovirus-based therapeutic vaccine for colorectal cancer effectively eliminates already established intestinal tumors in an animal model, and the understanding of the immune mechanism by which pseudovirus vaccines eradicate colorectal tumorigenesis will further our knowledge for designing vaccines for other cancers.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1576. doi:1538-7445.AM2012-1576
Abstract 158: Cyclopamine, an inhibitor of hedgehog signaling, induces monocytic differentiation of acute myelogenous leukemia cells
Authors: Bai Li-Yuan , Weng Jing-Ru , Chiu Chang-Fang , Lo Wen-Jyi , Lin Cheng-Wen
Published: August 2012

Introduction: Sonic hedgehog homolog (Shh) is known to play a critical role in normal cellular expansion and in the patterning of the early embryo of vertebrates and invertebrates, and is also implicated in some human cancers. While the sonic hedgehog homolog (Shh) pathway has been implicated in hematopoiesis and in maintenance of hematological malignancy, there is little evidence to demonstrate its importance to differentiation therapy. Procedures: We characterized the changes in HL-60 [an acute myelogenous leukemia (AML) cell line] after blocking the Shh pathway by an antagonist of Smoothened, cyclopamine. Findings: The existence of Shh signaling pathway in HL-60 cells was demonstrated by reverse transcription and PCR. Cyclopamine at 20 μM significantly down regulated the mRNA expression of Smo, Gli1 and Gli2. The flow cytometry showed that cyclopamine mediated apoptotic death of HL-60 cells in a dose- and time-dependent manner. After 12 h and 24 h, cyclopamine at 5 μM and 10 μM significantly increased the G0/G1-phase fraction of cells. Furthermore, treatment with cyclopamine increased the expression of monocytic cell markers CD 11b and CD 14, but the expression of CD 13, CD 33 and CD 38 was unchanged in HL-60 cells. The ability of cyclopamine to induce the monocytic differentiation of HL-60 cells was further evidenced by increased Egr-1 expression in a dose-dependent manner. Cyclopamine also down-regulated the phosphorylation of Akt and ERK, but activated AMPK signaling. We also analyzed the effect of cyclopamine on the primary leukemia cells from patients with AML. Conclusions: Blocking the Shh pathway via cyclopamine causes a time- and dose-dependent apoptotic cell death, increases the proportion of cells in G0/G1-phase and induces monocytic differentiation in HL-60 cells. Cyclopamine also down-regulates the mRNA expression of genes in Shh pathways. Further investigations are needed to determine the clinical application of modulating the Shh pathway in the treatment of hematological malignancies.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 158. doi:1538-7445.AM2012-158
Abstract 1589: Isorhamnetin suppresses skin cancer through direct inhibition of MEK1 and PI3-K
Authors: Kim Jong-Eun , Lee Dong-Eun , Won Ki , Son Joe Eun , Seo Sang Kwon , Li Jixia , Kung Sung Keun , Heo Yong-Seok , Mottamal Madhusoodanan , Bode Ann M. , Dong Zigang , Lee Hyong Joo
Published: August 2012

Isorhamnetin is a plant flavonoid that is found in fruits and medicinal herbs and exerts anticancer effects. However, the underlying molecular mechanism of the chemopreventive potential of isorhamnetin remains unknown. Here, we report anti-skin cancer effects of isorhamnetin. In an in vivo mouse xenograft model injected with A431 human skin epithelial carcinoma cells, isorhamnetin reduced tumor growth and COX-2 expression. Isorhamnetin inhibited epidermal growth factor (EGF)-induced neoplastic cell transformation of JB6 mouse epidermis cells and anchorage-dependent and -independent growth of A431 cells. Isorhamnetin attenuated EGF-induced cyclooxygenase (COX)-2 expression in JB6 cells and A431 cells. The EGF-induced phosphorylation of extracellular signal-regulated kinases, p90 and p70 ribosomal S6 kinases, and Akt was suppressed by isorhamnetin. In vitro and ex vivo kinase assay data demonstrated that isorhamnetin inhibited the kinase activity of MEK1 and PI3-K and the inhibition was due to direct binding with isorhamnetin. Notably, isorhamnetin bound directly to MEK1 in an ATP-noncompetitive manner and to PI3-K in an ATP-competitive manner. Overall, these results indicate that isorhamnetin has potent anti-cancer activity and it primarily targets MEK and PI3-K, which might contribute to the chemopreventive potential of certain foods.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1589. doi:1538-7445.AM2012-1589
Abstract 1594: Chemopreventive action of Piper nigrum on cell proliferation and apoptosis in skin papillomagenesis and its influence on the levels/activity of enzymes associated with xenobiotic metabolism and antioxidant status in Swiss albino mice
Authors: Singh Manju
Published: August 2012

Piper nigrum a spice, has widely used in various systems of traditional medicine. Therefore, the present study was designed to investigate the chemopreventive potential of P. nigrum on cell proliferation, apoptosis in DMBA-induced skin papillomagenesis and its influence on the levels/activity of enzymes associated with xenobiotic metabolism and antioxidant status in mice. Two different doses (2 and 4%) of P. nigrum were given orally to the mice in the test diet at peri-initiational stage. DMBA and croton oil was used to induce and promote skin papillomagenesis respectively. For biochemical studies, mice were given with the same doses of P. nigrum in the test diet for two weeks. There was a significant reduction in (i) tumor burden to 3.0 and 2.4 (positive control: 6.4); (ii) tumor volume to 1.7 and 2.4 (positive control: 4.7); and (iii) tumor incidence 60 % and 50 %, respectively in case of 2 and 4% test diet treated animals relative control (100%). P. nigrum treatment resulted in upregulation of Bax with concomitant decrease in antiapoptotic protein Bcl-2 and PCNA in mouse skin tumors. P. nigrum showed a significant increase in the content/activities of phase I and phase II enzymes with the test diets. A significant enhancement in the activities of antioxidant enzymes were observed at 2 and 4% test diets of P. nigrum. Glyoxalase I activity and the content of reduced glutathione were significantly elevated. Expectedly, the activity of lactate dehydrogenase, exhibited a significant reduction at both the doses of test diets. The Chemopreventive effect of P. nigrum could be credited to its ability to inhibit cell proliferation and enhance apoptosis as well as to modulate phase I, phase II enzyme systems and also antioxidant status. The present findings may have some significance from the point of view of lowering the risk of cancer in human population.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1594. doi:1538-7445.AM2012-1594
Abstract 1632: Novel naproxen, resveratrol and sulforaphane (NRS) combinations demonstrate synergistic decrease in cell viability of human colon and pancreatic cancer cell lines
Authors: Grandhi B. Karthik , Thakkar Arvind , Prabhu Sunil
Published: August 2012

Gastrointestinal cancers, in particular colon and pancreatic cancer, account for almost 100,000 deaths each year in the United States, ranking third and fourth respectively, in the most common cause of cancer related deaths. Our lab has been focused on developing strategies for chemoprevention rather than treatment after diagnosis. For pancreatic cancer, the prognosis is usually poor with high mortality rates after diagnosis. Thus, the objective of this work was to study the effects of chemopreventive combination regimens of a non-steroidal anti-inflammatory drug (NSAID) naproxen (N), in combination with resveratrol (R, an antioxidant) and sulforaphane (S, a broccoli extract) on human colon (HT-29 and HCT-116) and pancreatic (MIA PaCa-2 and Panc-1) cancer cell lines. MTS cell proliferation assay was conducted on all cell lines. For the MTS assay, upon 75 % confluence, 100µL of 2.5X103 cells each of HT-29, HCT116 and MIA PaCa-2 and 4X10 3 cells Panc-1 cells were transferred into each well of 96-well plates. The NRS chemopreventive agents alone, or in combination, were added to the cells and incubated for 72 h. The plates were then incubated for 1-4 h at 37°C in a humidified, 5% CO2 atmosphere. Absorbance was recorded at 490 nm using an ELISA plate reader. For HT-29 and HCT 116 colon cancer cell lines, the combinations of naproxen (500µM/L) with resveratrol (50µM/L) and sulforaphane (5µM/L) showed reduction in cell viability of 56.74% and 52.9%, respectively. The IC50 values for NRS were 1.46 mM/L,104.54µM/L and 17.81µM/L respectively on HT-29 cell line. Similarly, for MIA PaCa-2 and Panc-1 pancreatic cancer cell lines, combinations of naproxen (500µM/L) with resveratrol (6µM/L) and sulforaphane (5µM/L) showed reduction in cell viability of 66.67% and 58.8% respectively. The IC50 values for NRS were 778µM/L, 74.8µM/L and 11.82µM/L respectively, on MIA Paca-2 cell line. When used individually, none of the chemopreventive agents at the above concentrations demonstrated any decrease in cell viability, however when combined together, a synergistic effect was observed. Our results demonstrate that NRS drug combinations at low concentrations exhibit significant decrease in cell proliferation in both human colon and pancreatic cancer cell lines. This data provides compelling evidence of the potential of these combination regimens for the chemoprevention of colon and pancreatic cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1632. doi:1538-7445.AM2012-1632
Abstract 1640: Unidentified genetic variants influence pancreatic cancer risk: An analysis of the PanScan genome-wide association study
Authors: Pierce Brandon L. , Tong Lin , Kraft Peter , Ahsan Habibul
Published: August 2012

Genome-wide association (GWA) methods have been used to identify multiple pancreatic cancer susceptibility loci. However, it is likely that other unidentified common susceptibility variants exist. In this work we used data on 493,619 common autosomal single nucleotide polymorphisms (SNPs) from the PanScan GWA study (2,857 cases and 2,967 controls) to confirm the existence of unidentified susceptibility variants using two cross-validation methods: a polygenic risk score (PRS) approach and a power-replication approach. For the PRS approach, after excluding all SNPs from known pancreatic cancer susceptibility loci, we first constructed a polygenic risk models based on a training dataset and then tested the model in an independent testing dataset. The second approach (i.e., “power-replication) was based on calculating power to detect association for each SNP based on association estimates from a training set and then testing the power estimate for association with probability of replication in an independent testing data set. Using the polygenic risk score method, we demonstrate the existence of additional pancreatic cancer risk variants, the majority of which have P-values > 0.01 in the PanScan study. We also demonstrate enrichment for unidentified loci near gene regions. We reach similar conclusions using the power-replications approach, where SNPs with higher power to detect association were more likely to be replicated in an independent dataset at P<0.05, especially when analyses were restricted to SNPs in gene regions. While our results do not substantially improve pancreatic cancer prediction, they do provide further rationale for focusing association studies on genic regions and suggest that conducting larger GWA studies and innovative secondary analyses have the potential to reveal novel susceptibility loci.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1640. doi:1538-7445.AM2012-1640
Abstract 1652: Targetome profiling and genetic association analyses implicate miR-202 in follicular lymphomagenesis
Authors: Hoffman Aaron E. , Liu Ran , Zheng Tongzhang , Fu Alan , Slack Frank , Zhu Yong
Published: August 2012

Complex etiologic heterogeneity among non-Hodgkin's lymphoma (NHL) subtypes has made it difficult to identify risk factors for this disease. However, recent genetic association analyses, including two genome-wide association studies, suggest that genetic susceptibility to NHL may be strongest for the follicular lymphoma subtype. As recent studies have demonstrated that microRNAs (miRNAs) may be important in the etiology of many cancer types, including NHL, we performed a population-based genetic association study which identified a polymorphism in the precursor of miR-202 that is strongly associated with follicular lymphoma risk (rs12355840 in miR-202: PTREND = 0.006). An in vitro functional genetics assay demonstrated that the polymorphism is biologically active, and operates by altering the processing efficiency of the miR-202 precursor to the mature effector miRNA species. A ribonucleoprotein immunoprecipitation-microarray (RIP-Chip) assay, performed with an anti-AGO2 antibody followed by a whole-genome array, was used to characterize the miR-202 targetome, and selected targets were confirmed using a 3′UTR luciferase assay. Among the identified targets were several transcripts with relevance for tumorigenesis, including the miRNA biogenesis gene DICER1 and the lymphoma-associated cell cycle regulator and proto-oncogene SKP2. Both of these genes have been shown to be upregulated in lymphomas, which is consistent with our data, which show that the miR-202 risk allele is associated with diminished mature miR-202 levels in vitro. Taken together, these findings suggest that rs12355840 may represent a novel risk biomarker for follicular lymphoma, and implicate miR-202 in follicular lymphomagenesis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1652. doi:1538-7445.AM2012-1652
Abstract 1653: Genetic variation in the vitamin D pathway and risk for colorectal cancer in African Americans
Authors: Pibiri Fabio , Kittles Rick A. , Sandler Robert S. , Keku Temitope O. , Kupfer Sonia S. , LLor Xavier , Ellis Nathan A.
Published: August 2012

Background: Colorectal cancer (CRC) is the third leading cause of cancer-related death in both sexes in the United States. There is a large disparity in both CRC incidence and survival between African Americans (AAs) and all other US racial groups. Differences in serum vitamin D levels could contribute to this disparity because vitamin D is thought to protect against CRC and AAs have lower serum vitamin D levels. In addition, genetic variants in vitamin D-related genes could modify the association between vitamin D levels and CRC risk. Methods: We tested for associations between CRC and 39 single nucleotide polymorphisms (SNPs) in vitamin D-related genes (CYP27A1, GC, CYP3A4, CYP2R1, DHCR7/NADSYN1, VDR, CYP27B1 and CYP24A1). We genotyped 357 AAs cases and 443 AA controls from the North Carolina Colorectal Cancer Study. We calculated odds ratios (OR) using logistic regression, assuming an additive genetic model and controlling for age, gender, and ancestry. We also analyzed SNP associations for colon and rectal cancer cases separately. We analyzed linkage disequilibrium and haplotype association using Haploview. Results: Associations (p<0.05) were detected between CRC and two SNPs in the vitamin D binding protein gene GC, rs3755967 (OR, 0.69; P = .039,) and rs16847024 (OR, 1.50; P = .047,). We also detected an association with a SNP in the 24-hydroxylase gene CYP24A1, rs73913755 (OR, 0.75; P = .034,), which degrades vitamin D. A trend for association was detected in the 25-hydroxylase gene CYP2R1, rs10741657 (OR, 0.79; P = .051), which converts cholecalciferol into calcidiol. When we analyzed colon and rectal cancers separately, only one SNP was associated with colon cancer whereas 9 SNPs were associated with rectal cancer. In particular, rs73913755 (OR, 0.39; P = 3 x 10-7) was statistically significant even after adjustment for multiple testing. Conclusion: We tested vitamin D-related SNPs and found suggestive evidence that they influence the risk of developing CRC in AAs, with differences in risk between the colon and rectum. Comparison of these data with data from US whites could shed light on disparities in these different US populations.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1653. doi:1538-7445.AM2012-1653
Abstract 1664: A functional study of missense variants localized in the DNA binding domain of BRCA2
Authors: Guidugli Lucia , Pankratz Vernon Shane , Erding Catherine A. , Goldgar David E. , Couch Fergus J.
Published: August 2012

Genetic evidence of pathogenicity is not available for most missense mutations (Variants of Uncertain Significance (VUS)) detected in the DNA binding domain (DBD) of BRCA2 by clinical genetic testing. In the absence of this evidence, functional assays may be useful for classification of the clinical relevance of these VUS. We used a cell based Homology-Directed repair reporter assay to characterize 14 known pathogenic and 18 known non-pathogenic BRCA2 missense mutations and 34 VUS from the DBD of BRCA2. We transfected each full-length wildtype and mutant BRCA2 construct into V-C8 BRCA2 deficient cells along with an I-Sce1-expression plasmid, which induces a unique double strand break in an integrated DR-GFP reporter plasmid. The protein expression levels were evaluated by immunoprecipitation and Western blotting. The ability of each BRCA2 mutant to repair the induced break was evaluated by fluorescent activated cell sorting (FACS) for GFP. The HDR assay exhibited 100% (95% CI: 75.3% - 100%) sensitivity and 100% (95% CI: 81.5% - 100%) specificity for pathogenic missense mutations. Next, we developed a statistical classifier for prediction of the pathogenicity or non-pathogenicity of BRCA2 variants based on results from the HDR assay. Using known pathogenic and non-pathogenic variants as standards we computed the probability that each variant is pathogenic or non-pathogenic based on HDR activity. A probability of 99% in favor of pathogenicity correctly classified the known pathogenic mutations and the non-pathogenic variants. The evaluation of an additional 34 variants identified 18 variants as deleterious and eight as neutral. In summary the HR assay serves as a reliable high-quality surrogate for classification of VUS located in the BRCA2 DBD.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1664. doi:1538-7445.AM2012-1664
Abstract 1667: Pathway analysis of bladder cancer genome-wide association study identifies several novel pathways involved in bladder cancer development
Authors: Chen Meng , Ye Yuanqing , Dinney Colin P. , Wu Xifeng
Published: August 2012

Recent genome-wide association studies (GWAS) have identified multiple genetic variants associated with bladder cancer risk but only explain a small fraction of the inherited variability. A recurring problem in traditional GWAS analysis (i.e., single-SNP analysis) is the lack of consideration of biological pathways that contains network of genes with subtle, undetectable effect at the single SNP or single gene level. Application of innovative secondary analyses focusing on genes and pathways will complement and expand traditional GWAS analysis and identify novel genes and pathways that are associated with bladder cancer risk. We used the genome-wide scan data from MD Anderson's bladder cancer case control study to identify cellular signaling pathways involved in bladder cancer tumorigenesis. Gene set enrichment analysis (GSEA) was applied as a secondary analysis of our previous bladder cancer GWAS data. GSEA can detect subtle effects of multiple SNPs in the same gene set, and multiple genes in the same biological pathway, which are often missed in traditional GWAS analysis. Using three GSEA approaches (Gen-Gen, Aligator, and SNP Ratio Test), we consistently identified 18 pathways significantly associated with bladder cancer risk. The top pathways included two cell cycle pathways involved in the G1/S transition (PGenGen: 0.001, PAligator: 0.001, PSRT: 0.002), neural cell adhesion molecule (NCAM) pathway (PGenGen:<0.001, PAligator: 0.020, PSRT: 0.014), platelet-derived growth factor (PDGF) induced intracellular pathway (PGenGen: <0.001, PAligator: 0.026, PSRT: 0.006) and unfolded protein response pathway (PGenGen: 0.007, PAligator: 0.001, PSRT: <0.001). We identified that CCNE1 rs8110447 and rs8102137 were the most significant SNPs and gene in the two cell cycle pathways. As previously reported in GWAS, CCNE1 at 19q12 is a hotspot for bladder cancer susceptibility. However, other pathways with known susceptibility genes, such as those containing GSTM1, were not significant in the GSEA analysis, suggesting that this approach has identified novel biological pathways involved in bladder cancer tumorigenesis. Future studies are needed to validate in independent population. Overall, these findings contribute to a coherent understanding of the overall gene networks involved in bladder cancer susceptibility as well as offer additional etiologic insights highlighting the specific genes and pathways involved.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1667. doi:1538-7445.AM2012-1667
Abstract 1672: Population prevalence of consensus translocations in follicular and mantle cell lymphomas
Authors: Hirt Carsten , Meier Manuela , Yu Kelly , Schüler Frank , Janz Siegfried , Dölken Gottfried , Rabkin Charles S.
Published: August 2012

Chromosomal translocations t(14;18)(q32;q21) of the anti-apoptotic gene BCL2 and t(11;14)(q13;q32) of the cell cycle regulatory gene cyclin D1 are hallmark mutations of follicular lymphoma (FL) and mantle cell lymphoma (MCL), respectively, both driven by the enhancer of the immunoglobulin heavy chain gene cluster IGH. These same translocations have also been detected at low frequency in peripheral blood lymphocytes (PBL) of clinically normal individuals, but association with risk of subsequent lymphoma remains to be determined. We therefore evaluated consensus PCR assays for these translocations towards development of potential blood screening tests of lymphoma risk. Formalin-fixed, paraffin-embedded tumor specimens were retrieved from 62 FL and 17 MCL diagnosed during a large population-based cancer screening trial. Lymphoma DNA was isolated from scrapings off glass slides and assessed for quality and quantity by quantitative real-time PCR amplification of the single copy reference gene KRAS. Samples were divided into three aliquots and tested with consensus primers to detect translocations within either the Major Breakpoint Region (MBR) on chromosome 18 or the Major Translocation Cluster (MTC) on chromosome 11, as appropriate. For MBR-positive reactions, PCR fragment length was estimated by agarose gel electrophoresis. Overall, 21 (34%) of 62 FL and 7 (44%) of 16 MCL were PCR-positive for the consensus translocation sequences. Translocation detection was highly dependent upon testing an adequate quantity of DNA, with 21 (45%) PCR-positives among 47 FL samples of at least 500 diploid genome equivalents vs. 0 (0%) positives among the remaining 15 FL (p<.001). PCR fragment lengths were identical from replicate assays for all but one MBR-positive sample, which yielded two products differing by 30 base pairs. Within the FL group, PCR-positivity did not significantly differ among Working Formulation histologies, including 2 (15%) of 13 mixed small cleaved and large cell FL, 5 (36%) of 14 small cleaved cell FL, 6 (55%) of 11 large cell FL, 1 (100%) of 1 centroblastic lymphoma and 7 (30%) of 23 FL not otherwise specified. We confirmed that nearly half of FL and MCL with adequate samples in this population-based cohort study have consensus translocation sequences. Thus, translocation presence and/or frequency in stored pre-diagnostic PBL can be usefully examined for associations with risk of subsequent lymphoma. FL- and MCL-associated translocations in PBL are a potential target for cancer risk prediction and preventive intervention.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1672. doi:1538-7445.AM2012-1672
Abstract 1676: Associations between hormone therapy with incident colorectal cancer by p53 protein expression in a population-based cohort of older women
Authors: Tillmans Lori S. , Vierkant Robert , Wang Alice , Lynch Charles , Anderson Kristin , French Amy , Haile Robert , Harnack Lisa , Potter John , Slager Susan , Smyrk Thomas , Thibodeau Stephen , Cerhan James , Limburg Paul
Published: August 2012

Background: Cigarette smoking (CS) is an established colorectal cancer (CRC) risk factor. The p53 protein, encoded by the TP53 tumor suppressor gene that is commonly mutated in CRC, is important in cell cycle arrest needed to repair DNA damage or induce apoptosis to prevent tumor propagation. In this prospective cohort study, we examined CS-associated CRC risks by p53 protein expression level in the population-based Iowa Women's Health Study (IWHS). Methods: The IWHS recruited 41,836 randomly selected Iowa women, ages 55-69 years, with a valid driver's license at study entry (1986). CS and other exposure variables were assessed at baseline, by self-report. Incident CRC cases were ascertained by annual linkage with the Iowa Cancer Registry. Archived, paraffin-embedded tissue specimens were collected from 732 CRC cases diagnosed through 12/31/2002. CS was categorized by smoking status (never, current, former), average number of cigarettes per day (1-19, 20-39, > 40) and cumulative pack-years (1-19, 20-39, > 40). P53 protein expression was determined by immunohistochemistry on tissue microarrays. Tumor cores were scored by combining both staining intensity and percent of cells stained to determine negative, low or high p53 protein expression levels. Multivariate Cox regression models were fit to estimate relative risks (RRs) and 95% confidence intervals (CIs). Results: Of the 732 available CRC cases, 486 (66%) had complete CS and p53 data. Associations between CS and CRC subtypes defined by p53 expression level are shown in the Table. Conclusions: These data demonstrate no clear heterogeneity of CS with CRC subtypes defined by p53 expression levels among older women.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1676. doi:1538-7445.AM2012-1676