bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 18: Prohibitin 1 regulates apoptosis via its interaction with XIAP
Authors: Xu Yingjie , Yang Wen , Guarani Virginia , Shi Jinjun , Harper J. Wade , Zetter Bruce R.
Published: August 2015

Prohibitin 1 (PHB1) belongs to an evolutionarily highly conserved family of proteins that share the stomatin/prohibitin/flotillin/HflK/C (SPFH) domain. PHB1 has been implicated in the regulation of diverse cellular processes, including cell-cycle progression, transcriptional regulation, apoptosis, mitochondrial biogenesis, and as a cell-surface receptor. To better understand the function of PHB1, we analyzed PHB1 protein interactors using Immunoprecipitation followed by mass spectrometry analysis (IP-MS). We identified the X-linked inhibitor of apoptosis protein (XIAP) as a novel PHB1-binding partner. The interaction of PHB1-XIAP has been confirmed both in vitro and in vivo. Using immunofluorescence staining, We observed that PHB1 and XIAP colocalized upon induction of apoptosis. Using various XIAP mutant constructs, we showed that PHB1 binds principally to the BIR3 domain of XIAP. In addition, silencing of either PHB1 or XIAP sensitized cells to chemotherapeutic drug-induced cell apoptosis and partially rescued the chemosensitivity of resistant cancer cells. The observation that PHB1 silencing decreased XIAP levels with a concomitant increase in XIAP cleavage suggests that the formation of a PHB1-XIAP complex inhibits apoptosis by enhancing XIAP stability. Our findings indicate that the PHB1-XIAP complex promotes an anti-apoptotic response in cancer cells and reinforces the potential of PHB1 as a therapeutic target.

Citation Format: Yingjie Xu, Wen Yang, Virginia Guarani, Jinjun Shi, J. Wade Harper, Bruce R. Zetter. Prohibitin 1 regulates apoptosis via its interaction with XIAP. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 18. doi:10.1158/1538-7445.AM2015-18
Abstract 1807: Nuclear targeted gold nanoparticles for radiation enhancement
Authors: Hainfeld James F. , Smilowitz Henry M.
Published: August 2015

Gold nanoparticles (AuNP) have been shown to enhance radiation dose (Hainfeld et al, 2004) resulting in significant improvement in tumor control (Hainfeld et al 2008, 2010, 2012). AuNPs that target nuclear DNA have the potential to greatly improve such radiation dose enhancement due to the utilization of the cascade of low energy Auger electrons that follow x-ray absorption. If the AuNP binds to the DNA, these high LET electrons should greatly augment double strand breaks and tumor cell killing. While positively charged peptides are known to take NP into the cell nucleus, they are expensive and subject to proteolytic degradation. We reasoned that just putting a positive charge on the AuNP might mimic enhanced cellular uptake, endothelial escape and nuclear translocation. Such three nm AuNPs had high cell uptake but were retained in the endosome with none getting into the nucleus whereas one nm positively charged AuNPs were found in the cell nucleus and nuclear membrane as well as the cytoplasm as evidenced by light and electron microscopy. Nuclear-localized positively charged AuNPs were found predominantly over regions of heterochromatin. Cells incubated with positively charged AuNPs in vitro and then irradiated showed an increased number of H2AX binding sites as evidenced by fluorescence. Cell metabolism assays using MTT, a surrogate for cell viability, performed one, two and three days following radiation therapy, showed that cells irradiated after loading with positively charged, nuclear targeted AuNPs manifested some decrease in cell viability.

Citation Format: James F. Hainfeld, Henry M. Smilowitz. Nuclear targeted gold nanoparticles for radiation enhancement. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1807. doi:10.1158/1538-7445.AM2015-1807
Abstract 1824: Predictive value of neutrophil-lymphocyte ratio for the efficacy of preoperative chemotherapy in triple-negative breast cancer
Authors: Asano Yuka , Kashiwagi Shinichiro , Morisaki Tamami , Noda Satoru , Kawajiri Hidemi , Takashima Tsutomu , Onoda Naoyoshi , Hirakawa Kosei
Published: August 2015

Purpose: Abnormalities in the subpopulations in white blood cells, such as neutrophilia and lymphopenia, have been reported in tumor-bearing patients, and the neutrophil/ lymphocyte ratio (NLR) has been found to associate with prognosis in patients following radical surgery. The NLR was reported to associate with prognosis in cancer patients by influencing both cancer progression and chemosensitivity. The correlation between NLR and the outcome of neoadjuvant chemotherapy (NAC) in breast cancer patients has not been elucidated yet. The aim of this study is to evaluate NLR as one of the possible markers to predict the outcome of NAC in patients with TNBC by a retrospective investigation of the consecutive patient series treated with a standardized single protocol in our institute.

Experimental Design: NLR was evaluated in a total of 177 patients with early-stage breast cancer treated with NAC consisting FEC (5-fluorouracil, epirubicin, and cyclophosphamide) followed by weekly paclitaxel followed by curative surgery. The correlation between NLR and the prognosis including the efficacy of the NAC was evaluated retrospectively. NLR was calculated from the preoperative blood sample by dividing the absolute neutrophil count by the absolute lymphocyte count. On the basis of previous studies, an NLR value of 3.0 was used as the cut-off value to discriminate between high-NLR (3.0 and over) and low-NLR (less than 3.0) groups.

Results: NLR distributed from 0.5 to 10.6 with a median of 2.0. Fifty-eight patients with low NLR (less than 3) had a higher pCR rate (p<0.001), and more frequently diagnosed to have TNBC (p<0.001) compared with those with high NLR (3 and over). Among TNBC patients who achieved pCR, DFS (p = 0.006) and OS (p<0.001) were significantly longer in patients with low NLR than that with high NLR. Low NLR was associated with a significantly favorable prognosis in TNBC patients who achieved pCR, according to univariate analysis (p = 0.044, HR = 0.06).

Conclusions: Low NLR in patients with TNBC could be expected to show high efficacy, and favorable outcome after NAC.

Citation Format: Yuka Asano, Shinichiro Kashiwagi, Tamami Morisaki, Satoru Noda, Hidemi Kawajiri, Tsutomu Takashima, Naoyoshi Onoda, Kosei Hirakawa. Predictive value of neutrophil-lymphocyte ratio for the efficacy of preoperative chemotherapy in triple-negative breast cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1824. doi:10.1158/1538-7445.AM2015-1824
Abstract 183: Oncogenic miRNA miR-130a-induced inhibition of the growth regulator protein ZAR2 in TNBC cells
Authors: Misra Smita , Snghal Ashutosh , Chaudhuri Gautam
Published: August 2015

ZAR2 is C4-type zinc-finger protein that we found to suppress the growth of breast tumor cells. In the dividing breast cancer cells ZAR2 is primarily located in the cytosol. It probably inhibits the growth of the tumor cells through sequence-specific capture and degradation of certain mRNAs which are critical for the growth of the cells. We found that the level of ZAR2 protein is significantly lower in the highly aggressive breast cancer cells of the triple negative subtype (TNBC). Forced expression of ZAR2 in the TNBC cells prevented the proliferation and invasiveness of these cells. Major objective of the research presented here is to understand the mechanism of suppression of ZAR2 level in the TNBC cells. As ZAR2 mRNA levels are very similar in the TNBC and non-TNBC cells, we postulated that ZAR2 protein levels are down-regulated in the TNBC cells due to the induction of a ZAR2-targeting miRNA in these cells. We used computational prediction to identify potential microRNAs down-regulating ZAR2 in the TNBC cells. One of the major miRNAs that is predicted by DIANA-Tools (http://diana.imis.athena-innovation.gr/DianaTools/index.php?r = MicroT_CDS/index) to target ZAR2 mRNA is hsa-miR-130a-5p. We found that the level of miR-130a-5p in the TNBC cells is inversely related to the level of ZAR2 protein in the TNBC cells. We validated the binding of miR130a-5p miRISC to several specific locations at the 3′-UTR of ZAR2 mRNA and the inhibition of translation of ZAR2 mRNA by this miRNA. We propose that targeted knockdown of miR130a-5p in the TNBC cells will elevate the level of ZAR2 protein resulting in the inhibition of the growth of these cells. This research is supported in part by NIH/NCIgrant1R21CA181920-01 to GC and NIH grant 1U54RR026140 to SM.

Citation Format: Smita Misra, Ashutosh Snghal, Gautam Chaudhuri. Oncogenic miRNA miR-130a-induced inhibition of the growth regulator protein ZAR2 in TNBC cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 183. doi:10.1158/1538-7445.AM2015-183
Abstract 1830: Untargeted metabolomics reveals smokers’ characteristic profiles
Authors: Hsu Ping-Ching , Lan Renny S. , Brasky Theodore , Marian Catalin , Cheema Amrita K. , Ressom Habtom W. , Loffredo Christopher A. , Pickworth Wallace , Shields Peter G.
Published: August 2015

Introduction. Smoking-related biomarkers for lung cancer and other disease risks are needed to enhance early detection strategies and to provide a science base for FDA decision making for the regulation of tobacco products. Methods. An untargeted metabolomics approach was used in a cross-sectional study of smokers (n = 112) where subjects smoked 2 cigarettes one hour apart, and blood was collected immediately before and after each cigarette. The global metabolomic profiles from the two blood samples were determined using UPLC-Q-TOF/MS (n = 448 assays). The study design allows for the direct detection of smoking-related effects since each subject served as his/her own control. Results were analyzed by using a false discovery rate q value <0.05. Results. Pair-wise comparisons of pre- and post-cigarettes showed 24 features (metabolites) significantly changed due to smoking. The analysis identified important changes in menthol-glucuronide (p = 6.99E-10) and endogenously occurring metabolites including glutamate and glycerophospholipids. Menthol-glucuronide was positively correlated with glutamate, and negatively correlated with oleamide, lysoPC(16:1(9Z)), and an unknown metabolite with m/z of 517.31+ (p < 0.01), implying a menthol specific effect. Some shared and different metabolites were found by race and gender. Pathway analysis revealed smoking-related effects on carbohydrate metabolism, lipid metabolism, and small molecule biochemistry. Network analysis revealed eleven molecules involved in cancer, notably inhibition of cAMP. Conclusions. This first time identification of a menthol metabolite in blood samples from smokers serves as proof-of-principle for using metabolomics to identify new tobacco-exposure biomarkers. This study also identified several endogenous non-smoke metabolites not previously related to smoking carcinogenesis that may serve as biomarkers of exposure and/or effect (e.g., glutamate), and provides new biological insights for the effects of tobacco smoke on cellular functions.

Citation Format: Ping-Ching Hsu, Renny S. Lan, Theodore Brasky, Catalin Marian, Amrita K. Cheema, Habtom W. Ressom, Christopher A. Loffredo, Wallace Pickworth, Peter G. Shields. Untargeted metabolomics reveals smokers’ characteristic profiles. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1830. doi:10.1158/1538-7445.AM2015-1830
Abstract 184: miR-379/411 cluster regulates IL-18 and contributes to drug resistance in malignant pleural mesothelioma
Authors: Miyanaga Akihiko , Seike Masahiro , Yamamoto Kazuo , Takeuchi Susumu , Noro Rintaro , Minegishi Yuji , Kubota Kaoru , Gemma Akihiko
Published: August 2015

Malignant pleural mesothelioma (MPM) is a rapidly fatal malignancy that is increasing in incidence in Japan. In this study, we performed gene and microRNA (miRNA) expres¬sion profiling to identify novel therapeutic targets in MPM cells. Based on relative sensitivities to pemetrexed (PEM) and the histone deacetylase (HDAC) inhibitor, vorinostat (SAHA), 211H cells were determined to be the only sensitive MPM cell line out of the 6 tested. On the same series of cell lines, we performed whole genome transcriptomic profiling via DNA microarrays and pathway analysis of the derived data. Of particular note, IL-18 gene expression levels were signifi¬cantly higher in the cell lines that were either drug resistant or displayed intermediate sensitivity, compared to the sensitive 211H cell line. Pathway analysis revealed IL-18 as an impor¬tant gene associated with drug sensitivity of MPM cells. A relationship between IL-18 overexpression and drug resistance was also observed following targeted assessment of 10 cyto¬kine genes using quantitative RT-PCR. miRNA expression profiles were evaluated in the MPM cell line panel in order to discern the mechanism of IL-18 induction in the drug-resistant lines. We found that miR-379 and miR-411 belonged to the same cluster of miRNAs located on chromosome 14q32 that commonly target the IL-18 gene. Luciferase reporter assays revealed that miR-379 and miR-411 directly target the IL-18 gene. Introduction of miR-379 plus miR-411, as well as IL-18 silencing, significantly suppressed the invasive capacity of MESO1 cells in vitro. Furthermore, the use of either PEM or SAHA together with miR-379 plus miR-411 mimics mediated increased sensitivity to these drugs in MESO1 cells. These results suggest that the miR-379/411 cluster may provide new therapeutic opportunities for advanced MPM patients, depending on the nature of IL-18 gene expression.

Citation Format: Akihiko Miyanaga, Masahiro Seike, Kazuo Yamamoto, Susumu Takeuchi, Rintaro Noro, Yuji Minegishi, Kaoru Kubota, Akihiko Gemma. miR-379/411 cluster regulates IL-18 and contributes to drug resistance in malignant pleural mesothelioma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 184. doi:10.1158/1538-7445.AM2015-184
Abstract 1843: Novel actions of next-generation taxanes benefit advanced stages of prostate cancer
Authors: de Leeuw Renee , Berman-Booty Lisa , Schiewer Matthew , Ciment Stephen , Den Robert , Dicker Adam , Kelly William , Trabulsi Edouard , Lallas Costas , Gomella Leonard , Knudsen Karen
Published: August 2015

Purpose: To improve the outcomes of patients with castrate resistant prostate cancer (CRPC), there is an urgent need for more effective therapies and approaches that individual specific treatments for patients with CRPC. The current studies compared the novel taxane, cabazitaxel with the previous generation docetaxel, and aimed to determine which tumors are most likely to respond.

Experimental design: Cabazitaxel (CBTX) and docetaxel (DCTX) were compared via in vitro modeling to determine molecular mechanism, biochemical and cell biological impact, and cell proliferation, which was further assessed ex vivo in human tumor explants. Isogenic pairs of RB knockdown and control cells were interrogated in vitro, and in xenograft tumors for cabazitaxel response.

Results: The data herein show that i. CBTX exerts stronger cytostatic and cytotoxic response compared to DCTX, especially in CRPC; ii. CBTX induces aberrant mitosis, leading to pyknotic and multinucleated cells; iii. taxanes do not act through the androgen receptor (AR); iv. Gene expression profiling reveals distinct molecular actions for CBTX v. tumors that have progressed to castration resistance via loss of RB show enhanced sensitivity to CBTX.

Conclusions: CBTX not only induces improved cytostatic and cytotoxic effects, but also impacts distinct molecular pathways, compared to DCTX, which could underlie its efficacy after DCTX treatment has failed in CRPC patients. Finally, RB is identified as the first potential biomarker that could define the therapeutic response to taxanes in metastatic CRPC. This would suggest that loss of RB function induces sensitization taxanes, which could benefit up to 50% of CRPC cases.

Citation Format: Renee de Leeuw, Lisa Berman-Booty, Matthew Schiewer, Stephen Ciment, Robert Den, Adam Dicker, William Kelly, Edouard Trabulsi, Costas Lallas, Leonard Gomella, Karen Knudsen. Novel actions of next-generation taxanes benefit advanced stages of prostate cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1843. doi:10.1158/1538-7445.AM2015-1843
Abstract 1844: Genome wide analysis of AR-cell cycle interplay reveals novel functions in cancer
Authors: McNair Christopher , Goodwin Jonathan , Augello Michael , Urbanucci Alfonso , Schiewer Matthew , Comstock Clay , Ertel Adam , Wang Liguo , Wang Qianben , Mills Ian , Li Wei , Carroll Jason , Knudsen Karen
Published: August 2015

The androgen receptor (AR) plays a vital role in prostate cancer (PCa) due in part to its ability to interact with cell cycle components in order to drive cell cycle transition. Numerous points of cross-talk have been identified, wherein specific components of the cell cycle machinery “feed back” to modulate AR function, and these interactions are thought to be altered in human malignancies. Despite these observations, the majority of genome wide analyses for AR have been performed in cells that have exited cell cycle (G0). Here, the cell cycle dependent AR transcriptome and cistrome was identified, revealing new and unexpected functions for AR in cycling tumor cells. In studies to be discussed, cells were arrested in 5 distinct phases of the cell cycle, stimulated with androgen, and AR activity assessed through gene expression and ChIP-Seq analyses. In AR binding analyses, significant overlap was seen with previously identified sites, but were accompanied by novel binding events that could be segregated into those that are specific to cycling cells and occur in all phases (“cell cycle common”) or show cell cycle stage specific binding (“phase exclusive”). Over 50% of the cell cycle common sites, and up to 95% of the phases exclusive sites were novel AR occupied sites. Additionally, using a “guilty by association” approach to determine potentially AR regulated genes from this novel cistromic data, it was determined that close to 50% of cell cycle common, and 70% of phase exclusive binding uncover novel candidates for AR regulation. Cistrome data was therefore overlaid with microarray data, to prioritize discovery of meaningful, cell cycle specific AR binding events. Analyses to be discussed reveal striking new insight into disease relevant AR function. In sum, these data rigorously demonstrate that AR acts in a cell cycle dependent manner, and that these functions of AR have a major impact on tumor cell phenotypes.

Citation Format: Christopher McNair, Jonathan Goodwin, Michael Augello, Alfonso Urbanucci, Matthew Schiewer, Clay Comstock, Adam Ertel, Liguo Wang, Qianben Wang, Ian Mills, Wei Li, Jason Carroll, Karen Knudsen. Genome wide analysis of AR-cell cycle interplay reveals novel functions in cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1844. doi:10.1158/1538-7445.AM2015-1844
Abstract 1846: Catalytic topoisomerase II inhibitors suppress the androgen receptor signaling and prostate cancer progression
Authors: Li Haolong , Xie Ning , Gleave Martin , Dong Xuesen
Published: August 2015

Background: Although the new generation of anti-androgens (e.g. MDV) improves survival of metastatic prostate cancer patients, tumors eventually recur indicating that additional therapeutic means is required to fully block the functions of the androgen receptor (AR). Since DNA topoisomerase II (Topo II) was demonstrated to be essential for AR to initiate gene transcription, this study tested whether catalytic inhibitors of Topo II can suppress the AR signaling and block prostate tumor growth.

Methods and Results: Androgen-dependent and MDV-resistant prostate cancer cells were treated with increasing doses of catalytic Topo II inhibitors, ICRF187 and ICRF193. Luciferase reporter assays showed that both inhibitors suppressed the transcriptional activities of wild-type AR, mutant AR (F876L and W741C), and AR-V7 splice variant. ICRF187 and ICRF193 decreased AR recruitment to its target promoters and reduced AR nuclear localization. Both ICRF187 and ICRF193 inhibited androgen-dependent and MDV-resistant cancer cell proliferation and delayed cell cycling at the G2/M stages. In castration-resistant LNCaP tumors, ICRF187 inhibited tumor growth, PSA secretion and expressions of several other AR regulated genes. These repressive effects became stronger when tumors were co-treated with MDV. Additionally, ICRF187 effectively inhibited tumor growth of MDV-resistant MR49F as well as castration-resistant 22RV1 xenografts.

Conclusions: Catalytic Topo II inhibitors can block the AR signaling and inhibit tumor growth of castration-resistant xenografts, suggesting their potential applications in treating castration-resistant cancers in patients.

Citation Format: Haolong Li, Ning Xie, Martin Gleave, Xuesen Dong. Catalytic topoisomerase II inhibitors suppress the androgen receptor signaling and prostate cancer progression. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1846. doi:10.1158/1538-7445.AM2015-1846
Abstract 1875: Development of a dietary inflammation score and its association with incident, sporadic colorectal adenoma
Authors: Holmes Ashley C. , Bostick Roberd M.
Published: August 2015

It is now well established that inflammation is linked to colorectal carcinogenesis and other chronic diseases. The ability to characterize specific dietary and lifestyle components as having pro- or anti-inflammatory effects is a promising area of cancer prevention. We developed a “dietary inflammation score” based on associations of independent dietary components with plasma C-reactive protein (CRP) in the combined Markers of Adenomatous Polyps (MAPs) case-control studies, and investigated the association of the score with incident, sporadic colorectal adenoma in the same population. First, we excluded individuals who regularly took non-steroidal anti-inflammatory drugs (NSAIDs) and multivitamins, and among those remaining (n = 369) calculated the multivariable-adjusted associations of the individual dietary components with CRP, used the strengths of associations as weights, and summed the weighted dietary components to create an overall summary dietary inflammation score. Food components were included in the score based on biological plausibility and previous literature, and included four categories of meat, nuts, pepper, coffee, tea, high- and low-fat dairy products, refined and whole grains, and twelve botanical categories. The crude odds ratio (OR) for the association of the highest dietary score tertile with log-transformed CRP was 1.92 (95% confidence interval [CI]: 1.13, 3.27); after adjusting for age, sex, total energy intake, and lifestyle inflammation score category, the OR was 1.89 (95% CI: 1.06, 3.36). The association tended to be stronger among older individuals, males, and adenoma cases. The overall score was more strongly associated with CRP than was any individual dietary component. Next, to assess the association of the dietary inflammation score with adenomas, we used the entire MAPs population (n = 188 cases and 325 controls)– including the regular NSAID and multivitamin users. The crude OR for the association of the highest dietary score tertile with incident adenoma was 1.30 (95% CI: 0.84, 2.02), an association that tended to be stronger among men and those who regularly took aspirin or other NSAIDs. Multivariable adjustment did not appreciably change these estimates. The results from this pilot study suggest that diet may contribute to systemic levels of inflammation, and support further investigation of a dietary inflammation score with colorectal neoplasms and other chronic diseases in larger studies.

Citation Format: Ashley C. Holmes, Roberd M. Bostick. Development of a dietary inflammation score and its association with incident, sporadic colorectal adenoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1875. doi:10.1158/1538-7445.AM2015-1875
Abstract 1879: Prospective study of marine ω-3 polyunsaturated fatty acids and risk of colorectal cancer according to microsatellite instability
Authors: Song Mingyang , Nishihara Reiko , Wu Kana , Qian Zhi Rong , Kim Sun A. , Sukawa Yasutaka , Mima Kosuke , Inamura Kentaro , Masuda Atsuhiro , Yang Juhong , Fuchs Charles S. , Giovannucci Edward L. , Ogino Shuji , Chan Andrew T.
Published: August 2015

Background: Chronic inflammation is involved in the development of colorectal cancer (CRC) and microsatellite instability (MSI), a distinct phenotype of CRC. Experimental evidence indicates an anti-inflammatory and antineoplastic effect of marine ω-3 polyunsaturated fatty acids (PUFAs). However, epidemiologic data remain inconclusive.

Methods: We investigated whether the association between marine ω-3 PUFAs and CRC varies by MSI-defined subtypes of tumors in the Nurses’ Health Study and Health Professionals Follow-up Study. We collected updated data on marine ω-3 PUFA intake and documented 1,125 CRC cases during 24-26 years of follow-up. We determined the MSI status of tumors using 10 microsatellite markers, and classified cases into MSI-high tumors in which ≥30% of the microsatellite markers demonstrated instability, and microsatellite stable (MSS) tumors in which <30% of the markers demonstrated instability. Cox proportional hazards model was used to estimate the hazard ratio (HR) and 95% confidence interval (CI) of microsatellite stable (MSS) tumors and MSI-high tumors in relation to marine ω-3 PUFA intake.

Results: There was no statistically significant association between marine ω-3 PUFA intake and overall incidence of CRC. However, a statistically significant difference was detected by MSI status (Pheterogeneity = 0.02): high marine ω-3 PUFA intake was associated with a lower risk of MSI-high tumors (comparing ≥0.30g/d to <0.10g/d: multivariable HR = 0.54, 95% CI = 0.35 to 0.83, P for linearity = 0.03) but not MSS tumors (HR = 0.97, 95% CI = 0.78 to 1.20, P for linearity = 0.28). This differential association appeared to be independent of CpG island methylator phenotype and BRAF mutation status.

Conclusions: High marine ω-3 PUFA intake is associated with lower risk of MSI-high CRC but not MSS tumors, suggesting a potential role of ω-3 PUFAs in protection against CRC through DNA mismatch repair. Further research is needed to confirm our findings and elucidate potential underlying mechanisms.

Citation Format: Mingyang Song, Reiko Nishihara, Kana Wu, Zhi Rong Qian, Sun A. Kim, Yasutaka Sukawa, Kosuke Mima, Kentaro Inamura, Atsuhiro Masuda, Juhong Yang, Charles S. Fuchs, Edward L. Giovannucci, Shuji Ogino, Andrew T. Chan. Prospective study of marine ω-3 polyunsaturated fatty acids and risk of colorectal cancer according to microsatellite instability. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1879. doi:10.1158/1538-7445.AM2015-1879
Abstract 1894: Transcriptomic profile analysis of PANC-1 cells in response to metformin and aspirin
Authors: Yue Wen , Wang Tao , Yang Chung S. , Xu Qing , DiPaola Robert S. , Tan Xiang-Lin
Published: August 2015

The commonly used drugs, metformin and aspirin have been studied extensively as cancer preventative and therapeutic agents. However, the underlying molecular mechanisms for the inhibitory effects of pancreatic cancer development remain largely unknown. To gain further insight into their biological function in pancreatic cancer, we conducted a transcriptomic analysis using RNA sequencing to assess the differential gene expression induced by metformin (5 mM) and aspirin (2 mM), alone or in combination, after treatment of PANC-1 cells for 48 hours. Compared to untreated control, metformin alone up-regulated 109 genes, and down-regulated 78 genes, aspirin alone down-regulated 43 genes only, while the combination of metformin and aspirin up-regulated 499 genes, and down-regulated 702 genes (fold-change > 2, P < 10−5). Of the top 25 genes (fold-change > 10, P < 10−10) regulated by the combination of metformin and aspirin, NGFR, NPTX1, and UNC5B were up-regulated more than 10-fold, while PCDH18, CCL2, RASL11A, FAM111B, BMP5, SKIDA1, and CDH18 were down-regulated more than 15-fold. The ingenuity pathway analysis (IPA) was applied to explore the top signaling pathways regulated by metformin and aspirin. The top canonical pathways, “cholesterol biosynthesis”, “cell cycle: G1/S checkpoint regulation”, and “axonal guidance signaling” were the most statistical significant pathways that were modulated by the combination of metformin and aspirin. It is worth noting that the axon guidance signaling and the cholesterol biosynthesis pathways have recently been reported to play an important role in the development of pancreatic cancer. Further studies are warranted to explore the effects of metformin and aspirin on these two pathways. Although results are preliminary and need further functional validation, these data provide, for the first time, a transcriptional profile of pancreatic cancer cells in response to metformin and aspirin.

Citation Format: Wen Yue, Tao Wang, Chung S. Yang, Qing Xu, Robert S. DiPaola, Xiang-Lin Tan. Transcriptomic profile analysis of PANC-1 cells in response to metformin and aspirin. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1894. doi:10.1158/1538-7445.AM2015-1894
Abstract 1897: Metformin as a chemoprevention agent for lung squamous cancer
Authors: Asiedu Michael K. , Barron Matthew R. , Aubry Marie Christine , Wigle Dennis
Published: August 2015

Background: Squamous cell carcinoma is a common type of lung cancer and accounts for about 25-30% of all non-small cell lung cancers. Metformin is a drug commonly prescribed as first-line treatment for type-2 diabetes, with some evidence showing that the drug can also act directly on cancer cells. One of the mechanisms of action is through activation of the AMP-activated protein kinase (AMPK) which is involved in control of energy homeostasis in cells. The goal of this study was to determine metformin response in different cell lines and different cellular contexts, and to use that information to work towards the generation of a metformin “sensitivity index” that could be used guide individualized chemoprevention.

Methods: We performed cell survival analysis on squamous cell carcinoma lines, skin fibroblast lines and differentiated IPS cell lines to identify differences in metformin response both for different cell lines and for cells in different cell context. Microarray profiling was used to determine differentially expressed genes that are regulated by metformin treatment in order to generate signatures of metformin response.

Results:

Cell survival analysis showed that different cell lines respond differently to metformin, and cells of identical genotypes in a variety of differentiated states or cellular contexts also show differential response to metformin. Gene expression profiling of metformin treated cells identified differentially expressed genes that may mediate metformin response.

Conclusion: Differences in response to metformin treatment across a variety of cell lines and cellular contexts suggest heterogeneity that may be patient-specific. Using genes that are differentially expressed following metformin treatment, we identified a 55-gene set that can be used as a metformin “sensitivity index” to stratify patients into metformin responders and non-responders and guide individualized chemoprevention.

Citation Format: Michael K. Asiedu, Matthew R. Barron, Marie Christine Aubry, Dennis Wigle. Metformin as a chemoprevention agent for lung squamous cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1897. doi:10.1158/1538-7445.AM2015-1897
Abstract 1899: Anti-skin tumor promoting effects of pentacyclic triterpenes found in Perilla frutescens
Authors: Cho Jiyoon , Rho Okkyung , Junco Jacob , Slaga Thomas J. , Camelio Andrew M. , Siegel Dionicio , DiGiovanni John
Published: August 2015

In this study, we conducted a comprehensive examination of a series of pentacyclic tritperpenes found in P. frutescens, including ursolic acid (UA) oleanolic acid (OA), augustic acid (AA), corosolic acid (CA), 3-epi-corosolic acid (3-epiCA), maslinic acid (MA), and 3-epi-maslinic acid (3-epiMA) for their effects on epidermal cell signaling, proliferation, and skin inflammation in relation to their ability to inhibit skin tumor promotion by TPA. For these experiments, female ICR mice (7-9 weeks of age) were treated with either acetone or 2 μmol of UA, OA, AA, CA, 3-epiCA, MA, or 3-epiMA 30 min prior to TPA (6.8 nmol) treatment The treatment protocol involved twice weekly treatments over a two week period. Mouse epidermis (6 hr time point) and whole skin (48 hr time point) were collected for Western blot analysis and histological analysis, respectively. Pretreatment with these compounds inhibited the activation of JNK1/2, Src, and Stat3 as well as the induction of Cox-2 protein. Pretreatment with the compounds also reversed the effect of TPA on PDCD4 and p27, and increased the activation of AMPK and LKB1. We also examined the effect of the compounds on TPA-induced epidermal hyperproliferation as assessed by epidermal thickness and epidermal labeling index (LI). All of the compounds examined significantly inhibited TPA-induced epidermal hyperproliferation (significant reductions in both epidermal thickness and LI). In addition, the effect of the triterpenes on TPA-induced infiltration of mast cells in dermis was evaluated. UA significantly inhibited the infiltration of dermal mast cells induced by TPA. Notably, OA, AA, CA, 3-epiCA, MA, and 3-epiMA produced a greater inhibitory effect than that seen with UA on the number of infiltrated mast cells. Thus, UA and a series of related triterpenes differentially inhibited multiple signaling pathways, epidermal hyperproliferation, and a marker of skin inflammation (infiltrated mast cells) induced by TPA. Several of the compounds including CA, 3-epiCA, MA, and 3-epiMA were particularly effective in these experiments. We are currently testing the ability of this group of compounds to inhibit skin tumor promotion by TPA in a two-stage skin carcinogenesis experiment. Collectively, the current data suggest that several pentacyclic triterpenes, in addition to UA, may have potent chemopreventive activity. Research supported by CA164159.

Citation Format: Jiyoon Cho, Okkyung Rho, Jacob Junco, Thomas J. Slaga, Andrew M. Camelio, Dionicio Siegel, John DiGiovanni. Anti-skin tumor promoting effects of pentacyclic triterpenes found in Perilla frutescens. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1899. doi:10.1158/1538-7445.AM2015-1899
Abstract 190: Modulation of MiR-21 signaling by MPS1 in human glioblastoma
Authors: Maachani Uday Bhanu , Tandle Anita , Shankavaram Uma , Kramp Tamalee , Camphausen Kevin A.
Published: August 2015

Monopolar spindle 1 (MPS1) is an essential spindle assembly checkpoint (SAC) kinase involved in determining spindle integrity. Beyond its mitotic functions, it has been implicated in several other signaling pathways. Its overexpression in cancer cells is known to contribute to genomic instability and tumorigenesis. Our earlier studies have elaborated on role of MPS1 in glioblastoma (GBM) radiosensitization. In this study using reverse phase protein arrays (RPPA), we assessed MPS1 mediated cell signaling pathways and demonstrated that inhibiting MPS1 could upregulate the expression of the tumor suppressor genes PDCD4 and MSH2 by downregulating micro RNA-21 (MiR-21). In GBMs MiR-21 expression is significantly elevated and is associated with chemo and radioresistance. Here, we show that MPS1 inhibition significantly repressed MiR-21 levels and elevated PDCD4 and MSH2 expression in GBM cells both in vitro and in vivo. Both MPS1 and MiR-21 depletion suppressed GBM cell proliferation, whereas, ectopic expression of MiR-21 rescued GBM cell growth from MPS1 inhibition. Further, we demonstrate that MPS1 mediates phosphorylation of SMAD3 but not SMAD2 in GBM cells; A possible mechanism behind MiR-21 modulation by MPS1. Collectively, our results shed light onto an important role of MPS1 in TGF-β/SMAD signaling via MiR-21 regulation. We also, evaluated the prognostic effect of MiR-21, PDCD4 and MSH2 expression on survival in GBM patients of different molecular subtypes from The Cancer Genome Atlas (TCGA) database, showing tumors with high MiR-21 expression and low PDCD4 and MSH2 expression were associated with significantly shorter survival times. To our knowledge this is the first report to demonstrate the role of MPS1 in MiR-21 modulation. This scenario in which MiR-21 is modulated by MPS1 inhibition may be exploited as a potential target for effective GBM therapy.

Citation Format: Uday Bhanu Maachani, Anita Tandle, Uma Shankavaram, Tamalee Kramp, Kevin A. Camphausen. Modulation of MiR-21 signaling by MPS1 in human glioblastoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 190. doi:10.1158/1538-7445.AM2015-190
Abstract 1933: Alteration of the protein tyrosine phosphatome in cancer
Authors: Moskal Damian , Tonks Nicholas K. , Lucito Robert
Published: August 2015

While the importance of receptor tyrosine kinase pathways in cancer has and continues to be carefully studied there are more than 100 tyrosine phosphatases, either receptor or non receptor, that also play an important role in cancer development. However there has been no comprehensive study of all PTPs or the protein tyrosine phosphatome (PTPome), to identify which have a role in cancer. We as a cancer community are fortunate to have access to a wide array of data types from a number of data sources such as TCGA, where we can determine if the PTPs are mis regulated in more than 20 types of cancers, totaling close to 4,000 samples. We utilized TCGA data for all tumor types with mature data sub setting the data to analyze the PTPome for all data types including expression, methylation, copy number and sequence data where available. Our intention was to use the genomic data to identify PTPs that were important to specific cancers as well as to understand which PTPs play an important role in multiple tumor types. Presently we have studied copy number variations, expression and methylation changes in 20 different tumor types. Thus far, copy number variations, as could be expected were extremely useful to determine the primary mutations in specific tumor types as well as PTPs that are found recurrently in multiple tumor types but not as useful to identify a number of PTPs that are co-altered or altered in the same individual tumors. We were surprised to find that the methylation data was not very useful to identify alterations but could use the methylation data to corroborate other alterations found. Presently we are also using the methylation data to determine if it can be used to identify possible clinical correlations. The expression data has been very useful to identify co-altered PTPs. Interestingly we found several PTPs that are altered together (for example, PTPN6, PTPN7, PTPN18, PTPN22, PTPRC, DUSP2 and DUSP22 with an overall pvalue of 0.02 and much lower if measured between any two PTPs in this list). In addition we have found PTPs that are co-altered in a specific tumor type but possibly more interesting PTPs that are co-altered in a number of tumor types. We are now studying if our results can be used to determine if these PTPs represent multiple specific pathways that are advantageously altered in carcinogenesis.

Citation Format: Damian Moskal, Nicholas K. Tonks, Robert Lucito. Alteration of the protein tyrosine phosphatome in cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1933. doi:10.1158/1538-7445.AM2015-1933
Abstract 1935: Gene expression analysis reveals distinct pathways of resistance to antiangiogenic therapy in ovarian cancer
Authors: Devapatla Bharat Kumar , Jaiprasart Pharavee , Woo Sukyung
Published: August 2015

Purpose: The rapid development of resistance after an initial response phase is a major challenge of antiangiogenic therapies. The molecular mechanisms underlying clinical resistance to antiangiogenic therapies are not yet well understood. We aimed to identify potential mediators of resistance to antiangiogenic therapy, with a view toward eventually developing therapeutic approaches to improve antiangiogenic therapies.

Methods: We developed preclinical in vivo phenotypic resistance models of antiangiogenic therapy using human ovarian carcinoma cells. We used two representative anti-VEGF agents to block VEGF (bevacizumab, 10 mg/kg BIW, IP) or its receptor (sorafenib, 30 mg/kg daily, PO). The treatment was given until tumors showed a long-term trend toward continued progression after an initial response (resistant tumor). Whereas treatment-sensitive tumors were defined by a long-term trend toward stable disease or regression. We conducted next generation sequencing to compare changes in the gene expression in resistant and sensitive tumors, distinguishing their origin (tumor vs stroma cells). To get a more detailed perspective of the overall changes in gene expression, Gene Set Enrichment Analysis (GSEA) was performed by pair-wise comparison according to treatment outcome (resistant vs sensitive) with respect to bevacizumab and sorafenib, of which the entire MSigDB collections were compared to. Further, significantly enriched pathways were validated with clinical gene expression profiling studies of various tumor types deposited in GEO and ArrayExpress.

Results: Our GSEA analysis revealed significant differences (FDR<0.25) in enrichment of various pathways between sensitive and resistant tumors. We observed ERK, P38 MAPK, ATP dependent helicase activity, and phosphatidylinositide 3-kinases pathways are differentially enriched between sensitive and resistant phenotypes of bevacizumab-treated group. In sorafenib-resistant group, six pathways were enriched including E2F1, KRAS and PDGF regulated pathways.

Conclusions: Here, we report distinct pathways of response to bevacizumab and sorafenib in preclinical ovarian cancer models, which may provide critical insights into ovarian tumor's adaption during anti-VEGF blockade. These pathways may also provide important clues for identifying synergistic therapeutic strategies to overcome or delay resistance to antiangiogenic agents.

Citation Format: Bharat Kumar Devapatla, Pharavee Jaiprasart, Sukyung Woo. Gene expression analysis reveals distinct pathways of resistance to antiangiogenic therapy in ovarian cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1935. doi:10.1158/1538-7445.AM2015-1935
Abstract 1936: CoMEt: A statistical approach to identify combinations of mutually exclusive alterations in cancer
Authors: Wu Hsin-Ta , Leiserson Mark D.M. , Vandin Fabio , Raphael Benjamin J.
Published: August 2015

Identifying driver mutations in cancer genomes is a significant challenge due to the mutational heterogeneity of tumors: different combinations of somatic mutations drive different tumors, even those of the same cancer type. This mutational heterogeneity arises because driver mutations target genes in signaling and regulatory pathways, each of which can be perturbed in numerous ways.

We introduce CoMEt, an algorithm to identify combinations of candidate driver mutations de novo, without any prior biological knowledge (e.g. pathways or protein interactions). CoMEt searches for combinations of mutations that exhibit mutual exclusivity, a pattern expected for mutations in pathways. CoMEt uses an exact statistical test for mutual exclusivity that is less biased toward high frequency alterations than previous approaches and more sensitive in detecting combinations of lower frequency alterations. We compute the exact test using a novel tail enumeration procedure and also derive a binomial approximation. CoMEt simultaneously identifies collections of one or more combinations of mutually exclusive alterations, consistent with the observation of multiple hallmarks of cancer, and also performs simultaneous analysis of subtype-specific mutations. Finally, CoMEt uses an MCMC algorithm to sample from collections in proportion to their significance, summarizing the distribution in a marginal probability graph. We show that CoMEt outperforms other mutual exclusivity approaches on simulated and real data.

We apply CoMEt to hundreds of samples from four different TCGA cancer types: gastric cancer (STAD), glioblastoma (GBM) and acute myeloid leukemia (AML), and breast cancer (BRCA). We identify multiple mutually exclusive sets within each cancer type. These include the RTK/RAS pathway in gastric cancer, the Rb and p53 signaling pathways in glioblastoma, and a collection containing multiple kinases, including FLT3, as well as the RAS genes in AML. In addition, we analyze subtype-specific mutations using CoMEt by encoding the subtype of each sample and computing exclusivity between and within subtypes. We apply this approach using four gene expression subtypes of breast cancer and identify several pathways that are enriched for mutations in specific subtypes including the PI(3)K/AKT signaling pathway in the Luminal A subtype. Many of these overlap known pathways, but others reveal novel putative cancer genes. These findings provide testable hypotheses for experimental validation.

Citation Format: Hsin-Ta Wu, Mark D.M. Leiserson, Fabio Vandin, Benjamin J. Raphael. CoMEt: A statistical approach to identify combinations of mutually exclusive alterations in cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1936. doi:10.1158/1538-7445.AM2015-1936