bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5056: Perceptions related to breast cancer prevention and behavioral practices in underserved women participated in a CBPR intervention
Authors: Rahman Saleh M. M. , Harris Cynthia M. , Mitchell Miaisha , Soliman Karam F.
Published: May 2015

Objective: To assess perceptions, knowledge, behavioral practices in breast cancer screening among uninsured and underinsured women in Leon and Gadsden Counties in Florida.

Methods: Women recruited through Community Outreach and Preventive Services (COPS) Core of a P20 Center of Excellence for Cancer Research, Training and Community Service were surveyed as a part of preliminary evaluation (N=107).

Results: Participants ranged in age from 25 to 72 years, predominantly 50-59 years old (33%). Among these women 76% reported having a previous mammogram; however, only 21.7% have reported having a mammogram one year ago. Though 83% reported having a Clinical Breast Examination (CBE), about 24% reported having a CBE three years ago. About 66% women had a recent health care visit and about 10% reported health care visit one to two years ago. Perceived Barriers appeared to be significant factor in screening decision making process. Majority women considered not having enough money as a barrier (49%), however, 97% women agreed that no matter how expensive it is they would receive a mammogram if her doctor had ordered them. Women's knowledge about breast cancer and screening mammogram was relatively poor (mean score = 8 /17).

Conclusion: Though prevalence of screening mammogram has increased, however, financial barrier is still a significant factor in women's decision making process for screening mammogram. Intervention should target social disparity areas to improve screening utilization in underserved women.

Citation Format: Saleh M. M. Rahman, Cynthia M. Harris, Miaisha Mitchell, Karam F. Soliman. Perceptions related to breast cancer prevention and behavioral practices in underserved women participated in a CBPR intervention. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5056. doi:10.1158/1538-7445.AM2014-5056
Abstract 5058: MTHFR and health behaviors: A meta-analysis of epigenetic risks for breast cancer prevention
Authors: Gonzales Mildred Crisostomo , Shiao S. Pamela , Lie Amanda
Published: May 2015

Purpose: Breast cancer is the most common malignancy and the second leading cause of cancer death among women worldwide. Methylenetetrahydrofolate reductase (MTHFR) is one of the most studied low penetrant genes that are critical for methylation pathways for deoxyribonucleic acid (DNA) repair and normal cellular development. Methylation pathways are affected by health behaviors such as folate intake, alcohol consumption, and tobacco smoking. While there were several meta-analyses on the associations of MTHFR gene variations and BC, by far, no meta-analysis has been noted on the associations of health behaviors and MTHFR gene variations, with breast cancer.

Procedure: PubMed databases were searched by using a combination of key words including “breast cancer”, “MTHFR”, “folate”, “alcohol”, “smoking”, and “health determinants”. Initial search resulted 135 articles from 1999 to 2013. Studies were reviewed for case-control studies, and scored for quality using the standard rating indicators from Quality of Reporting of Meta-analyses. Repeated data from same authors and those with poor quality scores were excluded. Inter-rater reliabilities on data coding and quality scores were established for the selection of studies.

Findings: Preliminary results included 55 studies for a total of 22,077 breast cancer cases and 25,419 controls including 27 studies with Whites, 21 studies with Asians, and 7 studies with mixed Euramericans. Twelve studies included MTHFR gene counts with folate intake levels for 8,032 cases and 10,482 controls; 5 studies with alcohol consumption for 3,068 cases and 5,157 controls; and 5 studies with tobacco smoking status for 909 cases and 1233 controls. Preliminary analysis indicated that MTHFR 677CT was associated with increased risk of BC (P < 0.005). The results also suggested that low folate intake, heavy alcohol consumption, and tobacco smoking contributed to increased risks for BC.

Conclusion: Investigating the epigenetic risks including healthy life style factors in relation to gene variations has the potential to explain the influence of health behaviors on carcinogenesis. Translating the results from the meta-analysis of health behaviors in relation to epigenetics can provide meaningful insights on the prevention of breast cancer. The findings from the meta-analysis per various race-ethnicity groups can be useful for future development of culturally sensitive and personalized interventions to prevent and reverse breast cancer by promoting the healthy methylation pathways for cancer prevention.

Citation Format: Mildred Crisostomo Gonzales, S. Pamela Shiao, Amanda Lie. MTHFR and health behaviors: A meta-analysis of epigenetic risks for breast cancer prevention. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5058. doi:10.1158/1538-7445.AM2014-5058
Abstract 5089: Survivin safeguards chromosome numbers and protects from aneuploidy
Authors: Wiedemuth Ralf , Klink Barbara , Schroeck Evelin , Schackert Gabriele , Temme Achim
Published: May 2015

Survivin, belonging to the family of Inhibitor of Apoptosis proteins (IAP), is overexpressed in a broad variety of different tumor entities. Besides its role and function in apoptosis, Survivin forms in mitosis with its partners Borealin, inner centromere protein (INCENP) and the enzymatically active member Aurora B kinase the chromosomal passenger complex (CPC). The main function of this complex is sensing and correcting non-bipolar microtubule-kinetochore interaction, regulating chromosome segregation and cytokinesis. Some evidence points to a role of Survivin in connecting mitosis with control of cell cycle arrest. In this study, we assessed the role of Survivin in ensuring chromosomal stability and DNA integrity in HCT116, MCF-7, U87-MG and corresponding isogenic p53-deficient cells.

Knock down of Survivin, using retroviral short-hairpin RNAs, caused in all tested cell lines a heavily impaired cytokinesis resulting in polyploidy and poly-merotelic kinetochore spindle assemblies, irrespective of the p53 status. Surprisingly, cells with wild type p53 showed after Survivin RNAi an activation of p53 and accumulation of p21waf/cip and Cyclin D1, indicating G1 arrest. A detailed Flow Cytometry analysis revealed a correlation between the increased p21waf/cip expression and increasing DNA content in Survivin-depleted wild type cells compared to p53-deficient cells. Conversely, BrdU incorporation in wild type cells decreased with DNA content compared to p53-deficient cells with knock down of Survivin. Nonetheless, polyploid wild type cells even with a DNA content larger 4n were still able to incorporate BrdU, indicating transient G1 arrest after Survivin knock down. Furthermore, Survivin RNAi led in all tested cell lines to an induction of DNA lesions and caused a DNA damage response. SKY-analysis revealed numerical aberrations and a significant higher frequency of structural chromosomal aberrations indicative for DNA double strand break repair, only in Survivin-depleted cells.

In conclusion, our results highlight the important role of Survivin as a chromosomal passenger protein which in concert with its molecular partners Aurora B, INCENP, and Borealin, controls chromosomal segregation by regulating bipolar spindle attachment and cytokinesis and protects cells from polyploidy and chromosomal instability.

Citation Format: Ralf Wiedemuth, Barbara Klink, Evelin Schroeck, Gabriele Schackert, Achim Temme. Survivin safeguards chromosome numbers and protects from aneuploidy. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5089. doi:10.1158/1538-7445.AM2014-5089
Abstract 5092: Geminin regulates pre-replicative complex formation through the stabilization of CDT1 in mitosis
Authors: Kudo Yasusei , Tsunematsu Takaaki , Ishimaru Naozumi
Published: May 2015

Geminin, a factor essential to DNA replication, directly binds to the licensing factor CDT1 and inhibits pre-replicative complex (pre-RC) formation to avoid re-replication. Geminin protein expression is necessary during S, G2 and M phases of the cell cycle. In G1, geminin levels are kept in check by the anaphase-promoting complex/cyclosome ubiquitin ligase complex and its activator (APC/CCdh1), which targets geminin for proteasomal degradation to allow pre-RC formation. Conversely, from S to G2 is stabilized by the APC/C inhibitor Emi1 to ensure inhibition of Pre-RC formation. In this study, we found that Aurora-A phosphorylated geminin at Thr25 in M phase and the Aurora-A-mediated phosphorylation stabilized geminin by preventing its degradation via APC/C during mitosis. Aurora-A-mediated stabilization of geminin may further give rise to that of CDT1 protein to ensure pre-RC formation in the ensuing S phase. The Aurora-A-geminin-CDT1 axis, thus, represents a critical function for regulating proper DNA replication.

Citation Format: Yasusei Kudo, Takaaki Tsunematsu, Naozumi Ishimaru. Geminin regulates pre-replicative complex formation through the stabilization of CDT1 in mitosis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5092. doi:10.1158/1538-7445.AM2014-5092
Abstract 5094: Investigating the role of CDC25B in inhibition of cellular proliferation
Authors: Lee Caleb C. , Manfredi James
Published: May 2015

CDC25B is a dual specificity phosphatase that activates cyclin-dependent kinases to trigger entry into mitosis and is required for re-entry into mitosis after DNA damage. As an oncogene, CDC25B is overexpressed in multiple tumor types. It has been specifically associated with prostate cancer, where overexpression is seen in prostate tumor tissues and higher levels correlate with increased tumor grade. In the prostate, in addition to its role as a cell cycle regulator, CDC25B acts as an androgen receptor coactivator increasing the response of reporter genes to the addition of androgen analogues. In a transgenic mouse model, overexpression of CDC25B in the mammary glands led to accelerated mammary epithelial proliferation resulting in hyperplasia, while in vitro, co-transfection of CDC25B with Ras allows for transformation of MEF's.

Surprisingly, given the establishment of CDC25B as an oncogene, colony formation assays using ectopic expression of CDC25B in transformed cell lines reveal an anti-proliferative effect. Our data reveal a role for Ras inhibition as a cause of this anti-proliferative effect. Co-transfection of CDC25B and Ras results in a dose-dependent decrease in expression of the ectopic Ras protein in several cell lines tested. Preliminary experiments suggest that while mRNA levels remain stable, CDC25B inhibits Ras protein expression. As Ras is pivotal in multiple tumors, this effect of CDC25B may be broadly applicable. These data therefore reveal a new role for CDC25B, which may need to be overcome to allow transformation of tumor cells.

Citation Format: Caleb C. Lee, James Manfredi. Investigating the role of CDC25B in inhibition of cellular proliferation. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5094. doi:10.1158/1538-7445.AM2014-5094
Abstract 5095: Real-time FUCCI imaging of cell cycle phase in tumors demonstrates why cancer chemotherapy is not effective in solid cancers
Authors: Yano Shuya , Tome Yasunori , Zhang Yong , Hiroshima Yukihiko , Miwa Shinji , Uehara Fuminari , Suetsugu Atsushi , Kishimoto Hiroyuki , Tazawa Hiroshi , Zhao Ming , Fujiwara Toshiyoshi , Hoffman Robert M.
Published: May 2015

The phase of the cell cycle can determine whether a cancer cell can respond to a given drug. The present report describes technology to monitor real-time cell cycle dynamics of cancer cells throughout a live tumor in vivo using a fluorescence ubiquitination cell cycle indicator (FUCCI). In nascent tumors in nude mice, approximately 30% of the cells in the center of the tumor are in G0/G1 and 70% in S/G2/M. In contrast in an established tumor, approximately 90% of cancer cells in the center are in G0/G1 phase. Similarly, approximately 75% of cancer cells far from (>100 µm) tumor blood vessels are in G0/G1. Longitudinal real-time imaging demonstrated that cytotoxic agents killed only proliferating cancer cells at the surface of tumors and, in contrast, had little effect on quiescent cancer cells that are the vast majority of an established tumor. Moreover resistant quiescent cancer cells that moved to the tumor surface restarted cycling after the cessation of chemotherapy. Most drugs currently in clinical use target cancer cells in S/G2/M which our results show are a small minority in established tumors, thereby accounting, at least in part, for poor efficacy of cytotoxic drugs in solid cancer. Our results also suggest that drugs that target quiescent cancer cells are urgently needed.

Citation Format: Shuya Yano, Yasunori Tome, Yong Zhang, Yukihiko Hiroshima, Shinji Miwa, Fuminari Uehara, Atsushi Suetsugu, Hiroyuki Kishimoto, Hiroshi Tazawa, Ming Zhao, Toshiyoshi Fujiwara, Robert M. Hoffman. Real-time FUCCI imaging of cell cycle phase in tumors demonstrates why cancer chemotherapy is not effective in solid cancers. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5095. doi:10.1158/1538-7445.AM2014-5095
Abstract 5110: The role triptolide in sensitizing lung tumor cells to cisplatin-induced apoptosis
Authors: Wang Gan , Xu Xiaoxin Susan , Zhang Yi
Published: May 2015

Cisplatin is an anticancer drug used in treatment for many types of cancer, including lung cancer. The quick development of tumor cell drug resistance, however, greatly hindered the effectiveness of cisplatin in cancer treatment. Exploring new strategies that can sensitize tumor cells to cisplatin treatment, therefore, is essential for improving the effectiveness of cisplatin in cancer treatment. Triptolide is a bioactive ingredient isolated from Tripterygium wilfordii, a traditional Chinese herbal medicine that has been used to treat immune-related disorders. Recent studies revealed that Triptolide possesses potent antitumor properties through CDK7-depedent RNA polymerase II (Pol II) degradation and global transcription inhibition by binding to the XPB subunit of general transcription factor TFIIH and inhibiting its ATPase activity. We have studied the possibility of using Triptolide to sensitize lung tumor cell to cisplatin-induced apoptosis. Using both HTB182 and CRL5985 lung tumor cells, our caspase 3 activation studies demonstrated that the presence of low-level Triptolide greatly sensitized these lung tumor cells to cisplatin-induced apoptosis. Our western blots results indicated that the presence of low-level Triptolide increased the cisplatin-induced expression of PUMA but reduced expression of Bcl-XL in these lung tumor cells. Our immune-blotting studies revealed that the RNA Pol II level was not significantly affected by the presence of low-level Triptolide. Our real time PCR studies results indicated that expression levels of several tested genes also were not affected by the presence of Triptolide. These results suggest that the presence of low levels of triptolide sensitizes the lung cancer cells to cisplatin-induced apoptosis through binding to XPB of the TFIIH and inhibiting the DNA repair activity for cisplatin DNA damage, resulting in increased apoptosis of the lung tumor cells. Therefore, the presence of low levels of triptolide sensitizes lung tumor cells to cisplatin-induced apoptosis.

Citation Format: Gan Wang, Xiaoxin Susan Xu, Yi Zhang. The role triptolide in sensitizing lung tumor cells to cisplatin-induced apoptosis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5110. doi:10.1158/1538-7445.AM2014-5110
Abstract 5119: Smac mimetic inhibits tumorigenicity and growth of glioblastoma by promoting differentiation of glioblastoma cancer stem-like cells
Authors: Tchoghandjian Aurelie , Jennewein Claudia , Eckhardt Ines , Momma Stefan , Figarella-Branger Dominique , Fulda Simone
Published: May 2015

Inhibitors of apoptosis (IAP) proteins are often overexpressed in human cancers including glioblastoma (GBM) and are well characterized for their antiapoptotic properties. Recently, a broader role of IAP proteins in tumor biology has been described, as they also regulate several non-apoptotic signal transduction pathways. Therefore, we investigated the effect of non-toxic concentrations of small-molecule Smac mimetics, which antagonize IAP proteins, on differentiation of cancer stem-like cells (CSLCs) derived from primary GBM specimens. Since CSLCs have been implicated in resistance to chemo- and radiotherapy and tumor recurrence, they are considered as critical therapeutic targets in GBM. Here, we identify a novel function of Smac mimetic in regulating differentiation of GBM CSLCs by activating NF-κB. Smac mimetic at non-lethal doses stimulates morphological changes associated with differentiation of GBM CSLCs. Smac mimetic increases transcriptional activity, mRNA and protein levels of the astrocytic marker GFAP without altering expression of the neuronal marker β-III-tubulin, indicating that Smac mimetic induces astrocytic differentiation of GBM CSLCs. Molecular studies reveal that Smac mimetic triggers processing of the NF-κB subunit p100 to p52, nuclear translocation of p52 and p50 and increased NF-κB DNA-binding. Intriguingly, inhibition of NF-κB by overexpression of dominant-negative IκBα superrepressor (IκBα-SR) blocks the Smac mimetic-stimulated increase in GFAP and differentiation. Interestingly, this Smac mimetic-stimulated differentiation is associated with reduced expression of stemness markers such as CD133, Nanog and Sox2 in GBM CSLCs. In contrast, Smac mimetic does not alter cell morphology, differentiation and expression of stemness markers in non-malignant neural stem cells. Importantly, Smac mimetic treatment reduces clonogenicity of GBM CSLCs in vitro and in vivo, suppresses their tumorigenicity in orthotopic and subcutaneous mouse models of GBM and significantly increases the survival of mice bearing GBM. By identifying a novel role of Smac mimetic in promoting the differentiation of GBM CSLCs, these findings provide new insights into Smac mimetic-regulated non-apoptotic functions with important implications for targeting GBM CSLCs.

Citation Format: Aurelie Tchoghandjian, Claudia Jennewein, Ines Eckhardt, Stefan Momma, Dominique Figarella-Branger, Simone Fulda. Smac mimetic inhibits tumorigenicity and growth of glioblastoma by promoting differentiation of glioblastoma cancer stem-like cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5119. doi:10.1158/1538-7445.AM2014-5119
Abstract 5128: Different effect of irinotecan induced apoptosis in k-Ras wild and mutant type colon cancer cell lines
Authors: Kang Myoung Hee , Kim Jung Lim , Kim Bo Ram , Jang Yoo Jin , Lee Sun I. , Kim Jun Suk , Oh Sang cheul
Published: May 2015

Irinotecan(IRI) prevents DNA from unwinding by inhibition of topoisomerase I. Its main use is in colon cancer, in particular, in combination with other chemotherapy agents. Recent studies, those with

Irinotecan treatment has a synergistic effect appears. However, there is no study on the effect of the Irinotecan mono-treatment. In addition their roles and the underlying mechanism in anti-tumorigenic function of solid tumor, especially kras wild and mutant type colon cancer, are not yet known. Bax protein is a key mediator of apoptosis and might be related to chemosensitivity. In this work, we evaluated the anti-tumorigenic action of these Irinotecan anti-cancer agent with especially k-ras wild and mutant type colon cancer cell lines, and investigated their apoptosis-inducing effects as the potential mechanism in this process. The results show that the growth inhibitory effects of 5-fuorouracil (5-FU), Oxaliplatin(OX) produced a dose- and time dependent fashion in k-ras wild(HT29, Colo205) and mutant type(HCT116, DLD-1) colon cancer cell lines. Otherwise, Irinotecan(IRI) produced a cell growth of k-ras wild type cell lines were resistant versus that shown in the sensitive k-ras mutant type cell lines. Cell cycle analysis by FACS indicated that IRI-treated cell lines showed an increase in the proportion of cells in sub-G1 phase, compared to untreated cells. Exposure of colon cancer cells to IRI also resulted in the increase in the percentage of annexin V- positive and PI-negative cells. The results by multiple in vitro experimental model, showed that IRI induce these k-ras mutant type colon cancer cells to undergo apoptosis with increased the Bax protein and a release of cytochrome C from mitochondria, the activation of caspase9, the cleavage of PARP. But Bax protein was inactivation in k-ras wild type colon cancer cell lines. Importantly, inhibition of ERK kinase activity demonstrated that IRI-induced apoptotic pathway was regulated by the ERK signaling cascade. These data indicate that Anti-cancer agent, Irinotecan, promotes

Bax-mediate apoptosis of colon cancer cell lines by sequential activation of the ERK signaling pathway followed by the up-regulation of intrinsic pathway of caspase 9.

Citation Format: Myoung Hee Kang, Jung Lim Kim, Bo Ram Kim, Yoo Jin Jang, Sun Il Lee, Jun Suk Kim, Sang cheul Oh. Different effect of irinotecan induced apoptosis in k-Ras wild and mutant type colon cancer cell lines. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5128. doi:10.1158/1538-7445.AM2014-5128
Abstract 5138: Histone deacetylase 2 and N-Myc reduce p53 protein phosphorylation at serine 46 by repressing gene transcription of tumor protein 53-induced nuclear protein 1
Authors: Shahbazi Jeyran , Scarlett Christopher J. , Norris Murray , Liu Bing , Haber Michelle , Tee Andrew E. , Carrier Alice , Biankin Andrew V. , London Wendy B. , Marshall Glenn M. , Lock Richard , Liu Tao
Published: May 2015

Myc oncoproteins and histone deacetylases (HDACs) exert oncogenic effects by modulating gene transcription. Paradoxically, N-Myc induces p53 gene expression. Tumor protein 53-induced nuclear protein 1 (TP53INP1) phosphorylates p53 protein at serine 46, leading to enhanced p53 activity, transcriptional activation of p53 target genes and programmed cell death. We aimed to identify the mechanism through which N-Myc overexpressing p53 wild-type neuroblastoma cells acquired resistance to apoptosis.Gene and protein expression was analysed by real-time RT-PCR and immunoblot. Cell survival/death was examined by flow cytometry study of Annexin V-staining. The prognostic value of TP53INP1 expression in tumor tissues was investigated in three independent cohorts of neuroblastoma patients. TP53INP1 was one of the genes most significantly repressed by HDAC2 and N-Myc according to Affymetrix microarray gene expression datasets. HDAC2 and N-Myc reduced TP53INP1 gene expression by direct binding to the TP53INP1 gene promoter, leading to transcriptional repression of TP53INP1, p53 protein de-phosphorylation at serine 46, neuroblastoma cell proliferation and survival. Moreover, low levels of TP53INP1 expression in human neuroblastoma tissues correlated with high levels of N-Myc expression and poor patient outcome, and the BET bromodomain inhibitors JQ1 and I-BET151 reduced N-Myc expression and reactivated TP53INP1 expression in neuroblastoma cells. These findings identify TP53INP1 repression as an important co-factor for N-Myc oncogenesis, and provide further evidence for the potential application of BET bromodomain inhibitors in the therapy of

N-Myc-induced neuroblastoma.

Citation Format: Jeyran Shahbazi, Christopher J. Scarlett, Murray Norris, Bing Liu, Michelle Haber, Andrew E. Tee, Alice Carrier, Andrew V. Biankin, Wendy B. London, Glenn M. Marshall, Richard Lock, Tao Liu. Histone deacetylase 2 and N-Myc reduce p53 protein phosphorylation at serine 46 by repressing gene transcription of tumor protein 53-induced nuclear protein 1. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5138. doi:10.1158/1538-7445.AM2014-5138
Abstract 5146: The histone demethylase KDM2A is a new promoter of tumorigenesis, drug target and negative prognostic biomarker for non-small cell lung cancer
Authors: Wagner Klaus W. , Alam Hunain , Dhar Shilpa S. , Giri Uma , Li Na , Wei Yongkun , Cascone Tina , Giri Dipak , Kim Jae-Hwan , Ye Yuanqing , Multani Asha , Chan Chia-Hsin , Erez Baruch , Saigal Babita , Lin Hui-Kuan , Wu Xifeng , Hung Mien-Chie , Heymach John , Lee MinGyu
Published: May 2015

The molecular etiology of non-small cell lung cancer (NSCLC) is heterogeneous and mostly dominated by alterations in kinase signaling pathways (i.e. KRAS, EGFR, EML4-ALK, PI3K, MEK1). Epigenetic modifiers, including histone methyltransferase and demethylases, have emerged as important regulators of oncogenic phenotypes in a small but growing number of tumor types, but the pathogenic role of histone methylation modifiers in NSCLC is largely unknown. We found that the histone H3 lysine 36 (H3K36) demethylase KDM2A is a novel oncogenic promoter of NSCLC. In our analysis KDM2A is frequently overexpressed in NSCLC cell lines and patient samples (≥14% in NSCLC tumors), and high expression levels of KDM2A correlate with poor prognosis in three independent patient populations from the USA and Asia.

KDM2A knockdown by RNAi in KDM2A overexpressing cell lines inhibits proliferation and invasiveness of NSCLC cells in vitro and in three mouse xenograft models (subcutaneous, intravenous, and orthotopic models). Consistently, KDM2A overexpression promotes these cellular characteristics in NSCLC cell lines with low endogenous KDM2A levels. Rescue experiments using KDM2A-depleted cells showed that ectopic expression of wild-type KDM2A, but not its catalytic mutant mKDM2A, restored proliferation and invasion. These results indicate that the effect of KDM2A on oncogenic phenotypes is largely dependent on its catalytic activity and validate it as drug target for development of small molecule inhibitors. Mechanistically, we uncovered, that KDM2A activates the MAPK signaling pathway (ERK1/2) by transcriptionally repressing the MAPK phosphatase DUSP3.

In summary, these novel findings indicate that KDM2A overexpression promotes NSCLC tumor growth and invasion. Our results provide new insights into how the dysregulation of an epigenetic enzyme can be coupled to activation of the ERK1/2 signaling pathway to promote NSCLC tumorigenesis and suggest that KDM2A is a promising anti-cancer therapeutic drug target for KDM2A-overexpressing NSCLC patients.

Citation Format: Klaus W. Wagner, Hunain Alam, Shilpa S. Dhar, Uma Giri, Na Li, Yongkun Wei, Tina Cascone, Dipak Giri, Jae-Hwan Kim, Yuanqing Ye, Asha Multani, Chia-Hsin Chan, Baruch Erez, Babita Saigal, Hui-Kuan Lin, Xifeng Wu, Mien-Chie Hung, John Heymach, MinGyu Lee. The histone demethylase KDM2A is a new promoter of tumorigenesis, drug target and negative prognostic biomarker for non-small cell lung cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5146. doi:10.1158/1538-7445.AM2014-5146
Abstract 5149: EZH2 as a novel therapeutic target in melanoma treatment
Authors: Tiffen Jessamy , Gunatilake Dilini , Gallagher Stuart , Gowrishankar Kavitha , Hersey Peter
Published: May 2015

Histone modifications are increasingly being recognized as an important epigenetic mechanism that governs chromatin structure and gene expression. EZH2 is the catalytic subunit of the polycomb repesssive complex 2 (PRC2), responsible for tri-methylation of lysine 27 residues on type 3 histones (H3K27Me3) that leads to gene silencing. EZH2 is found to be over-expressed in many different types of cancers, where it is postulated to abnormally repress tumor suppressor genes. Activating mutations described within the catalytic SET domain of EZH2 at codon 646 confer its oncogenic activity, as identified in approximately 3% of melanomas.

We sought to assess whether direct inhibition of EZH2's methyltransferase activity is a suitable strategy for melanoma treatment. This was tested using a small molecule inhibitor known as GSK126, a potent, highly selective drug that competes with S-adenosyl-methionine substrate. We found that both mutant and non-mutant EZH2 melanoma cell lines over-express EZH2 compared to primary cells, via western blot and that levels of H3K27 methylation were reduced following drug treatment. GSK126 significantly decreased proliferation and reduced the percentage of cells in the G1 phase of the cell cycle, most likely attributed to a G2 arrest. Flow cytometery also revealed an increased sub-G1 population, indicative of drug induced apoptosis. This was confirmed by Annexin-V staining. Growth inhibition by GSK126 was particularly effective in melanoma cells harboring EZH2 activating mutations and had little effect on primary cells that displayed low levels of EZH2.

Expression arrays and chromatin immunoprecipitation are being used to determine which PCR2 target genes are being de-repressed and to decipher the mechanisms of GSK126 growth inhibition. Collectively our initial data indicate that EZH2 represents a promising gene target for therapeutic intervention in melanoma in vitro and that in vivo studies are warranted.

Citation Format: Jessamy Tiffen, Dilini Gunatilake, Stuart Gallagher, Kavitha Gowrishankar, Peter Hersey. EZH2 as a novel therapeutic target in melanoma treatment. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5149. doi:10.1158/1538-7445.AM2014-5149
Abstract 515: G12 overexpression in hepatocellular carcinoma promotes epithelial-mesenchymal transition through microRNAs deregulation
Authors: Kim Sang Geon , Yang Yoon Mee , Kim Tae Hyun , Lee Chan Gyu , An Jihyun , Kim Sung Hoon , Lee Chang H. , Hwang Sejin , Lee Seung Jin , Kim Kang M.
Published: May 2015

Hepatocellular carcinoma (HCC) has a poor prognosis due to its aggressive nature. Ligand activation of G-protein coupled receptor with enhanced G-protein activity may contribute to tumorigenesis and tumor progression in microenvironments. Here, we report the overexpression of Gα12 in HCC and its effect on deregulation of microRNAs in association with epithelial-mesenchymal transition. Gα12 expression levels were higher in human HCC than surrounding normal tissue. Array analyses using Huh7 cells stably transfected with an active mutant of Gα12 (Gα12QL) enabled us to extract down-regulated microRNAs. Of them, decreases of miR-200b/a, -192 and -215 contributed to ZEB induction through the up-regulation of MDM2. Transfection with miR-200b, -192 or miR-215 mimic antagonized HCC cell migration and invasion facilitated by Gα12QL. In tumor xenograft studies, sustained knockdown of Gα12 decreased the overall growth rate and average volume of tumors derived from SK-Hep1, a mesenchymal liver tumor cell line. In human HCC samples, levels of the identified microRNAs were all decreased, and correlated with the induction of mesenchymal markers. Moreover, decreases of the miRNAs discriminated microvascular invasion versus non-microvascular invasion of HCC. Conclusion: Increase of Gα12 in HCC deregulates a set of miRNAs promoting epithelial-mesenchymal transition of HCC and may be responsible for tumor microvascular invasion, implying that Gα12 signaling and the downstream mediators may be utilized as therapeutic targets and/or prognostic markers.

Citation Format: Sang Geon Kim, Yoon Mee Yang, Tae Hyun Kim, Chan Gyu Lee, Jihyun An, Sung Hoon Kim, Chang Ho Lee, Sejin Hwang, Seung Jin Lee, Kang Mo Kim. G12 overexpression in hepatocellular carcinoma promotes epithelial-mesenchymal transition through microRNAs deregulation. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 515. doi:10.1158/1538-7445.AM2014-515
Abstract 516: Detection of human satellite RNA in the serum of high-risk patients of pancreatic cancer
Authors: Kishikawa Takahiro , Otsuka Motoyuki , Yoshikawa Takeshi , Ohno Motoko , Koike Kazuhiko
Published: May 2015

Introduction: Most satellite repeats in pericentmeric heterochromatin are epigenetically silenced and rarely transcribed into RNAs. However, in some pathological conditions, satellite RNA are transcribed and may deregulate cellular homeostasis. Recently, human satellite repeat II (HSATII) RNA were reported to be highly and specifically detected in human pancreatic cancers. However, precise localization of HSATII RNA expression in pancreatic cancer tissues and the time-course of its expression during carcinogenesis are unknown, mainly due to the technical difficulties to detect repetitive RNA sequences, which are difficult to amplify by PCR-based method. In this study, we determined the precise localization of HSATII RNA expression in pancreatic carcinoma tissues and developed a new method to detect HSATII RNA from the patient serum.

Methods: 1) Highly sensitive and specific custom-made locked nucleic acid-modified oligonucleotide probes were synthesized to detect HSATII RNA expression by Northern blotting and RNA in situ hybridization. Resected tissues containing pancreatic carcinoma lesions and those adjacent lesions in the same section from individual patients were used to determine the precise localization of HSATII RNA expression, along with tissue arrays. 2) Total RNAs were extracted from the serum of pancreatic cancer, intraductal papillary mucinous neoplasm (IPMN), and non-cancerous patients. Custom-made biotinylated RNA probes for HSATII RNA were hybridized with the patient RNA. Paired RNA was collected, and visualized by applying modified RNA protection method.

Results: 1) While no HSATII RNA expression was detected in pancreatic tissues without carcinoma, it was expressed in almost all pancreatic carcinoma tissues. Interestingly, the expression levels were clearly higher in non-cancerous lesions adjacent to carcinoma rather than in cancerous lesions themselves. 2) HSATII RNA was detected from 200 µl of the serum of pancreatic cancer and IPMN patients, whereas not detected from non-cancer patients.

Conclusion: HSATII RNA is highly expressed in the tissues surrounding human pancreatic cancerous lesions. This non-coding RNA could be detected in the serum of pancreatic cancer patients as well as patients with pre-cancerous lesions. These results may facilitate the development of novel methods to determine high-risk patients of pancreatic cancer.

Citation Format: Takahiro Kishikawa, Motoyuki Otsuka, Takeshi Yoshikawa, Motoko Ohno, Kazuhiko Koike. Detection of human satellite RNA in the serum of high-risk patients of pancreatic cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 516. doi:10.1158/1538-7445.AM2014-516
Abstract 5166: Characterization of somatic mutation spectrum in gastric cancer cases from Hispanic populations
Authors: Prieto Rodrigo , Lott Paul , Sahasrabudhe Ruta , Bohorquez Mabel , Castro Jorge , Mateus Gilbert , Echeverry Magdalena , Carmona Luis G. Carvajal
Published: May 2015

Gastric cancer is the second leading cause of cancer related deaths worldwide. Identification of gastric cancer drivers and somatic changes are essential to understand the molecular basis of tumorigenesis and to develop better preventive and therapeutic strategies. Till date, the large-scale initiatives to characterize somatic changes have been largely limited to Caucasian and Asian populations. This approach is likely to miss potential driver mutations that can be unique to other populations. Therefore, identification of somatic changes in cancers from multi-ethnic populations is essential to advance our understanding of tumor biology as well to bridge the gap in heath-care disparities. Hispanics are the largest and fastest growing minority in the USA and gastric cancer is a significant health care concern in this population. To understand molecular signatures of somatic alterations in gastric cancer in Hispanic population, we performed exome sequencing of 36 tumor samples and matched normal mucosa from gastric cancer patients from Colombia. In addition, we also performed microsatellite instability (MSI) testing and determined Epstein Barr virus and Helicobacter Pylori infection status for these samples. Our preliminary analysis of exome sequencing data by a locally developed pipeline indicates that the frequency of known cancer drivers in our study population in different than that has been reported previously and a subset of these cancers are following unique genetic pathways. In summary, our sequencing efforts in gastric cancer cases from Hispanic population are likely to identify novel cancer drivers and can help to further our understanding of molecular basis of this tumor type.

Citation Format: Rodrigo Prieto, Paul Lott, Ruta Sahasrabudhe, Mabel Bohorquez, Jorge Castro, Gilbert Mateus, Magdalena Echeverry, Luis G. Carvajal Carmona. Characterization of somatic mutation spectrum in gastric cancer cases from Hispanic populations. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5166. doi:10.1158/1538-7445.AM2014-5166
Abstract 5168: Gastric adenocarcinomas show pervasive loss of heterozygosity and enrichment for “STOP” genes in regions of hemizygous deletion
Authors: Cutcutache Ioana , Wu Alice Yingting , McPherson John R. , Lei Zhengdeng , Deng Niantao , Wong Wai Keong , Soo Khee Chee , Chan Weng Hoong , Ooi London Lucien , Welsch Roy E. , Tan Patrick , Rozen Steven G.
Published: May 2015

Purpose: Gastric cancer, the second leading cause of cancer death worldwide, has been little studied compared with other cancers that impose similar burdens on public health. Our goal is to assess loss of heterozygosity (LOH) and hemizygous deletion across a large series of gastric adenocarcinomas using the most sensitive and comprehensive method currently available.

Experimental design: We used high-density single-nucleotide-polymorphism microarrays that assay genotype and copy number at 906,600 sites and analyzed the results to determine patterns of LOH and hemizygous deletion in 77 gastric adenocarcinomas. We investigated whether “STOP” genes - genes that tend to impede proliferation - are associated with hemizygous deletion. We also analyzed the extent to which hemizygous deletion affected CYCLOPS (Copy number alterations Yielding Cancer Liabilities Owing to Partial losS) genes - genes that may be attractive targets for therapeutic inhibition when hemizygously deleted.

Results: We found that LOH is pervasive: on average 27% of each tumor genome is subject to LOH, and > 98% of single nucleotide polymorphisms assayed were subject to LOH in at least 10% of tumors. Furthermore, 26% of LOH was due to hemizygous deletion, and STOP genes were significantly associated with regions of frequent hemizygous deletion; on average, 61 STOP genes were hemizygously deleted per tumor. Furthermore, on average, 4.65 CYCLOPS genes were hemizygously deleted per tumor, and 54.5% of the tumors had at least one CYCLOPS gene deleted.

Conclusions: These findings suggest that hemizygous deletion of anti-proliferative STOP genes contributes substantially to gastric carcinogenesis. Furthermore, the presence of several hemizygously deleted CYLOPS genes in some tumors suggests potential therapeutic targets in these tumors.

Citation Format: Ioana Cutcutache, Alice Yingting Wu, John R. McPherson, Zhengdeng Lei, Niantao Deng, Wai Keong Wong, Khee Chee Soo, Weng Hoong Chan, London Lucien Ooi, Roy E. Welsch, Patrick Tan, Steven G. Rozen. Gastric adenocarcinomas show pervasive loss of heterozygosity and enrichment for “STOP” genes in regions of hemizygous deletion. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5168. doi:10.1158/1538-7445.AM2014-5168
Abstract 5180: Profiling signaling pathways in chronic lymphocytic leukemia using reverse phase protein array
Authors: Noonepalle Satish Kumar R. , Shull Austin , Awan Farrukh T. , Pei Leah , Ding Zhiyong , Shi Huidong
Published: May 2015

Chronic lymphocytic leukemia (CLL), the most common adult leukemia remains incurable despite advancements in treatment regimens over the past decades. B-cell receptor (BCR) mediated signaling is well recognized for its central role in the pathogenesis of CLL. Small molecular inhibitors targeting BCR signaling pathway and its downstream PI3K/AKT pathway are currently investigated in clinical trials because of their ability to induce apoptosis or block protein interactions in CLL cells. However, variability in pathological conditions and genetic aberrations render these small molecule inhibitors not equally effective in all CLL patients and highlights the need for individualized treatment options. In this pilot study, we analyzed differential protein expression of 18 CLL patient and 6 normal B-cell samples using reverse phase protein array (RPPA). RPPA enables us to study the proteome as well as phospho-proteome of CLL samples. When probed with 167 monoclonal antibodies RPPA revealed distinct protein expression patterns between CLL and normal B-cells. RPPA data was analyzed by unsupervised hierarchical clustering and CLL patient samples were clearly separated from normal B-cell samples. Proteins of BCR and downstream PI3K/AKT pathway such as SYK, LCK, PDK1, AKT, RICTOR, mTOR, TSC1, TSC2 and p70S6K were all upregulated in CLL samples. Harvesting the full potential of RPPA to study phosphorylation changes, we observed an increase in PI3K pathway activating signals such as PDK1-pS241, p70S6K-pT389, 4EBP1-pS65 and 4EBP1-pT70 suggesting a cell proliferative mechanism. There was also decrease in inhibitory signals such as RICTOR-pT1135. Pro-apoptotic factors BID, BAX, Caspase 7-cleaved and ANXA1 were poorly expressed in CLL samples compared to normal B-cells suggesting a defect in apoptosis mechanism is predominant in CLL samples. As previously reported, we have seen overexpression of anti-apoptotic factor BCL2. BIM isoforms, BIM-EL and BIM-L were overexpressed in CLL compared to normal samples; however the ratio of BIM-EL to BIM-L was higher in normal B cells compared to CLL cells. For the first time, we generated a comprehensive BCR protein and phospho-protein expression profiles in primary CLL samples. Our results reveal novel anti-apoptosis and cell proliferative mechanisms in CLL and potentially identified new therapeutic targets in CLL.

Citation Format: Satish Kumar R. Noonepalle, Austin Shull, Farrukh T. Awan, Leah Pei, Zhiyong Ding, Huidong Shi. Profiling signaling pathways in chronic lymphocytic leukemia using reverse phase protein array. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5180. doi:10.1158/1538-7445.AM2014-5180
Abstract 5181: Genomic and transcriptomic somatic alterations of hepatocellular carcinoma in non-cirrhotic livers
Authors: Griffith Obi L. , Lin Yiing , Griffith Malachi , Hundal Jasreet , Regier Allison , Fulton Robert , Brunt Elizabeth M. , Wilson Richard K. , Chapman William , Mardis Elaine R.
Published: May 2015

Background: In 2014, it is estimated that there will be over 30,000 new cases of hepatocellular carcinoma (HCC) and an estimated 20,000 subjects will die of this disease in the U.S. alone. Risk factors include chronic HBV/HCV infections, cirrhosis, alcohol abuse, diabetes, and fatty liver disease. However, an important subset of HCC occurs in the absence of any such risk factors. We surveyed the genomic and transcriptomic landscape of this subset of HCC.

Methods: We performed whole genome and transcriptome sequencing of 30 matched tumor and non-tumor liver samples from resections performed at Washington University School of Medicine. Somatic variants identified in this discovery set were extended to a set of 89 additional cases by custom capture sequencing for a total of 119 HCCs profiled. All data were processed through The Genome Institute's Genome Modeling System (GMS) to analyze for viral integrations, SNVs, Indels, CNVs, fusions, SVs, expression and differential expression.

Results: We report here for the first time the unique landscape of somatic alterations of HCC arising in non-cirrhotic liver. We detected and validated over 3,010 SNVs and indels in coding regions and 2,390 fusion transcripts, as well as extensive copy number and expression changes. We identified a single undiagnosed HBV case with viral integration occurring at the TERT promoter. We also confirmed recent reports of a recurrent TERT promoter mutation (G1295228A) occurring in at least 56% of cases. Additional recurrent mutations were observed in previously reported genes such as CTNNB1, TP53, AXIN1, and ARID1A, along with an increased frequency of RB1 loss, novel recurrent mutations of APOB, fusions in NR1H4, and other alterations. These molecular features were tested for association with clinical variables and outcome. Pathway analysis of recurrently altered genes suggests that, in the absence of external factors, genomic aberrations in basic liver metabolism genes may promote malignant transformation to HCC.

Citation Format: Obi L. Griffith, Yiing Lin, Malachi Griffith, Jasreet Hundal, Allison Regier, Robert Fulton, Elizabeth M. Brunt, Richard K. Wilson, William Chapman, Elaine R. Mardis. Genomic and transcriptomic somatic alterations of hepatocellular carcinoma in non-cirrhotic livers. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5181. doi:10.1158/1538-7445.AM2014-5181