bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 2738: Establishing an in vitro cell culture model for studying the function of FAM190A deletions
Authors: Calhoun Eric S. 
Published: July 2016

Abstract
A growing number of studies have reported a variety of genetic alterations to FAM190A (CCSER1) in cancer. Interestingly, a large percentage of these are focused on deleting downstream exons producing in-frame arrangements for this protein. An analysis of coding sequences reveals that regions of FAM190A are highly conserved throughout the N-terminus, however, with no recognizable protein domains. Published immunofluorescence and shRNA knockdown studies have since suggested that FAM190A is localized to the midbody during cytokinesis and may function in maintaining genome stability. Unfortunately, attempts to overexpress FAM190A were not successful by these authors. The aim of our current study was to try to generate an in vitro model that would allow us to examine the effect of a C-terminal deletion on cellular division and FAM190A's ability to associate with the spindle and/or midbody structures. To accomplish this, full length FAM190A and a deletion mutant construct lacking exons 8-11 were separately cloned into mammalian expression vectors that include a N-terminal HaloTag Fusion marker and a modified CMV promoter. Current studies are focused on introducing these constructs into the pancreatic cancer cell line, PL-5, to generate FAM190A stably expressing cell lines.
Citation Format: Eric S. Calhoun. Establishing an in vitro cell culture model for studying the function of FAM190A deletions. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2738.
Abstract 2744: Synthetic lethal killing of RAD54B-deficient cancer cells by PARP1 silencing and inhibition
Authors: McAndrew Erin N. , Lepage Chloe C. , McManus Kirk J. 
Published: July 2016

Abstract
Colorectal Cancer (CRC) is the second leading cause of cancer-related deaths in North America. Currently, many chemotherapeutics are non-specific and preferentially kill cancer cells based on their high proliferation rate. However, due to the lack of tumor specificity, many treatments have unwanted side effects. Accordingly, identifying novel therapeutic strategies and drug targets that better target and combat cancer are needed. To address this need, synthetic lethal (SL) approaches are now being explored in many cancer contexts. Synthetic lethality refers to the lethal combination of two independently viable mutations and functions by exploiting the aberrant genetics contained within cancer cells. RAD54B is an excellent candidate to exploit using a SL paradigm as it normally functions in homologous recombination repair (HRR) and hypomorphic expression and/or function are implicated in tumorigenesis in a wide array of cancers. We predict that RAD54B and PARP1 are SL, as BRCA1 and BRCA2, which also encode functions within HRR, are SL with PARP1. To identify PARP1 as a novel SL interactor of RAD54B, we employed an established RNAi-based screening approach along with a RAD54B isogenic CRC model. Conceptually, following PARP1 silencing, a SL interaction will result in fewer cells within the RAD54B-deficient cells relative to RAD54B-proficient controls. Accordingly, we sought to determine whether PARP1 silencing or inhibition (Olaparib or BMN673) would induce selective killing within RAD54B-deficient HCT116 cells relative to controls. As predicted, PARP1 silencing with either individual or pooled siRNA duplexes and inhibition with both Olaparib and BMN673 was associated with statistically significant decreases in the number of RAD54B-deficient cells relative to controls. To confirm the SL interaction did not occur due to de novo mutations within the RAD54B-deficient cells, dual silencing of RAD54B and PARP1 was performed within the parental line and confirmed the above findings. Finally, real-time cellular analyses were conducted and revealed the decrease in cell numbers was due to cellular cytotoxicity rather than cell cycle arrest. Collectively, these data show that RAD54B and PARP1 are SL, and identify PARP1 is a candidate lead target in CRCs harboring RAD54B defects.
Citation Format: Erin N. McAndrew, Chloe C. Lepage, Kirk J. McManus. Synthetic lethal killing of RAD54B-deficient cancer cells by PARP1 silencing and inhibition. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2744.
Abstract 275: Combining low dose microtubule targeting agents with belinostat potentiates cytotoxic response in HDACi resistant diffuse large b-cell lymphoma
Authors: Havas Aaron P. , Bhakta Anvi , Rodrigues Kameron , Smith Catharine L. 
Published: July 2016

Abstract
Patients diagnosed with Diffuse Large B-cell lymphoma have an overall 60% five-year survival rate. New therapeutic approaches are needed to effectively treat aggressive forms of DLBCL that are refractory to the standard treatment or that relapse within two years of treatment. Histone deacetylase inhibitors (HDACi) are novel therapeutics that are well tolerated in humans and are being extensively evaluated in combination with other therapeutics against hematologic malignancies. Rational selection of companion therapeutics has been difficult due to the cell type-specific mechanisms of HDACi action. In order to address this, we have developed a pre-clinical model system of sensitivity and resistance to HDACi-induced cytotoxicity in DLBCL cell lines that share characteristics with aggressive DLBCL tumors. We previously reported that HDACi resistance is associated with reversible arrest in G1 that involves sustained up-regulation of cyclin-dependent kinase inhibitors. In the current study we demonstrate that HDACi-sensitive cell lines undergo mitotic arrest prior to anaphase in response to treatment with the approved HDACi, belinostat, consistent with activation of the spindle assembly checkpoint (SAC). In contrast, HDACi-resistant cell lines are capable of completing mitosis in the presence of belinostat. To force SAC activation in HDACi resistant cell lines, we used low dose microtubule targeting agents (MTA) vincristine and paclitaxel to induce maximal mitotic arrest with minimal cytotoxicity. The combination of these low dose MTAs and belinostat efficiently caused SAC failure, mitotic slippage, and apoptosis in a synergistic manner. A key mechanism associated with resistance to MTAs is their ability to induce aneuploid cell populations that survive and undergo endoreduplication. The addition of belinostat eliminated the accumulation of a vincristine-induced aneuploid population. Pan-caspase inhibition in conjunction with belinostat and vincristine co-treatment resulted in a sustained survival of the aneuploid population. Thus belinostat triggers apoptosis in the aneuploid cells to enhance the cytotoxic effects of vincristine. Our study identifies the use of low dose MTA/HDACi combination as a potential therapeutic strategy for treatment of relapsed or refractory DLBCL.
Citation Format: Aaron P. Havas, Anvi Bhakta, Kameron Rodrigues, Catharine L. Smith. Combining low dose microtubule targeting agents with belinostat potentiates cytotoxic response in HDACi resistant diffuse large b-cell lymphoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 275.
Abstract 2756: SMARCAD1 depletion enhances hyperthermia-mediated radiosensitization by decreasing resection and enhancing stalled replication forks
Authors: Chakraborty Sharmistha , Hunt Clayton R. , Hambarde Shashank , Mujoo Kalpana , Horikoshi Nobuo , Pandita Raj K. , Mattoo Abid , Teh Bin , Pandita Tej K. 
Published: July 2016

Abstract
Hyperthermia is the most effective chemo- and radio-sensitizer in use clinically for containing tumor growth. Hyperthermia is proposed to induce degradation of BRCA2, the protein involved in homologous recombination (HR) repair of DNA double strand breaks and, thus sensitizes cells to poly (ADP-ribose) polymerase (PARP)-1 inhibition. We and other laboratories have reported that hyperthermia inhibits DNA damage repair. Since HR includes single-strand annealing, gene conversion and break-induced replication, it is critical for DNA replication during recovery of stalled replication forks, but it is not yet clear how hyperthermia affects these important steps in HR.
Here we report that SMARCAD1 depletion increases hyperthermia induced cell death and chromosome damage in irradiated S-phase cells. Combined SMARCAD1 depletion and hyperthermia treatment decreased repair and recruitment of repairosome proteins to ISce-1 induced DSBs as well as decreased IR-induced repairosome foci formation. This effect was limited to S-phase cells, where homologous recombination is up regulated and the predominant pathway of DSB repair. Hyperthermia decreased the quantity of 5′ single stranded DNA intermediates at endonuclease-generated DNA break sites, an effect that was further decreased by SMARCAD1 depletion. Consistent with these results, simultaneous SMARCAD1 depletion and hyperthermia increased replication fork stalling and affected firing of new replication origins. The results presented here support a mechanism by which SMARCAD1 depletion and hyperthermia mediate radiosensitization through inhibition of the DNA resection step that precedes strand homology search during HR repair of IR-induced DSBs.
Citation Format: Sharmistha Chakraborty, Clayton R. Hunt, Shashank Hambarde, Kalpana Mujoo, Nobuo Horikoshi, Raj K. Pandita, Abid Mattoo, Bin Teh, Tej K. Pandita. SMARCAD1 depletion enhances hyperthermia-mediated radiosensitization by decreasing resection and enhancing stalled replication forks. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2756.
Abstract 2767: Expression of miR-1252 and its target PRR4 gene in laryngeal carcinoma
Authors: BUYRU NUR , EKIZOGLU SEDA , GULIYEV JALAL , KARAMAN EMIN , ULUTIN. TURGUT 
Published: July 2016

Abstract
Head and neck squamous cell carcinoma (HNSCC) is the sixth most frequent cancer worldwide and includes neoplasias of the paranasal sinuses, the oral cavity, the trachea, the pharynx and the larynx. The most important risk factors are tobacco use, alcohol consumption and infection with human papillomavirus (HPV). Besides the exogenous risk factors, genetic factors may play a key role in the development of the HNSCC. Cancer of the larynx accounts for 25% of all head and neck malignancies.
The PRR4 (Prolin Rich Protein 4) gene is localized on human chromosome 12p13 and encodes a protein which is secreted from the acinar cells of the lacrimal gland, the submandibular gland, the parotis and the sublingual glands. Recent studies have demonstrated that PRR4 may play an important role as an antimicrobial protein to protect the ocular surface and the oral cavity. Additionally, it has been shown that PRR4 is highly expressed in the human submucosal glands.
microRNAs are small non-coding RNAs which regulate gene expression at the post-transcriptional level. They bind to their target RNA with their seed sequence complementary to the 3’UTR region. This interaction results in either up- or down-regulation of the target messenger RNA.
To understand the role of the PRR4 gene in laryngeal carcinogenesis, we investigated its mRNA expression levels in laryngeal tumor tissue and adjacent non-cancerous tissue samples from 90 patients by quantitative real-time PCR. As a complementary region between the seed sequence of miR-1252 and 3’UTR region of PRR4 gene exists, we also analyzed whether miR-1252 binds to this region and regulates the expression of PRR4.
We found that PRR4 gene expression was decreased in 65 (72.2%) and increased in 24 (26.7%) of 90 tumor tissues when compared to normal tissue. Statistically significant downregulation of the PRR4 mRNA was observed in laryngeal tumors (p&lt;0.001). No significant correlation was found between PRR4 gene expression and clinicopathological parameters including age, sex, stage, histological grade and tumor location (p&gt;0.05). We also analyzed miR-1252 expression levels in a subset of tumor samples. miR-1252 upregulation was observed only in 24% of tumor tissues compared to non-cancerous tissue. The miR-1252 level was same in the 62.5% of the remaining samples. We did not observe any correlation between the PRR4 and miR-1252 expression levels. Our results indicate that the PRR4 gene may have an impact in the progression of laryngeal carcinoma.
Citation Format: NUR BUYRU, SEDA EKIZOGLU, JALAL GULIYEV, EMIN KARAMAN, TURGUT ULUTIN. Expression of miR-1252 and its target PRR4 gene in laryngeal carcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2767.
Abstract 2768: Global DNA hypomethylation is an important feature of melanoma
Authors: Micevic Goran , Theodosakis Nicholas , Taube Janis M. , Bosenberg Marcus W. , Rodic Nemanja 
Published: July 2016

Abstract
Aberrant DNA methylation occurs nearly universally in cancer. Paradoxically, changes in DNA methylation are bi-directional: there is a focal increase in DNA methylation (hypermethylation), and a global overall decrease in DNA methylation (hypomethylation). Focal hypermethylation plays well described roles in silencing tumor suppressor genes in many malignancies, including melanoma. However, the functional role of global hypomethylation in tumorigenesis is relatively poorly understood. Melanoma is the deadliest form of skin cancer, accounting for approximately 74,000 new cases and 10,000 deaths in the United States in 2015. Changes in DNA methylation are also arguably one of the most common features of melanoma. Similar to other malignancies, most studies have focused on focal hypermethylation, identifying genomic loci differentially methylated between melanocytes and melanoma cells. However, global changes in DNA methylation have not been well described thus far. In this study, we describe global changes in DNA methylation in two melanoma clinical cohorts (JHH cohort, n = 13 nevi and n = 39 melanomas; NCI cohort n = 31 nevi and n = 97 melanomas) relative to benign nevi using a semi-quantitative immunohistochemistry based assay. We report a global decrease in DNA methylation levels in melanoma relative to benign melanocytic nevi consistent between both cohorts (p &lt; 0.001, Student's t-test). Furthermore, we studied the functional effect of increasing the level of global DNA methylation in a panel of five early passage melanoma cell lines. Increases in global DNA methylation suppressed proliferation of melanoma cells (p &lt;0.05, Student's t-test), and increased the proportion of apoptotic cells (p &lt;0.01, Student's t-test). Global DNA hypomethylation is thus an important epigenetic feature of melanoma that may regulate proliferative capacity, and merits further investigation.
Citation Format: Goran Micevic, Nicholas Theodosakis, Janis M. Taube, Marcus W. Bosenberg, Nemanja Rodic. Global DNA hypomethylation is an important feature of melanoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2768.
Abstract 2769: Response to 5FU therapy in colorectal cancer is affected by EZH2-mediated BclX splicing
Authors: Benderska Natalya , Gazouli Maria , Aravantinos Gerasimos , Hartmann Arndt , Schneider-Stock Regine 
Published: July 2016

Abstract
Background and Aims: The chromatin modifier EZH2 is remarkably up-regulated in many cancer types including colon cancer. High levels of EZH2 have been correlated with tumor metastasis and regulation of tumor-initiating cell subpopulation. Since, DZNep, an EZH2 inhibitor, can inhibit the growth capability of colon cancer by inducing apoptosis; down-regulation of EZH2 seems to be a promising therapeutic approach. Our preliminary data showed that EZH2 levels were remarkably increased in blood samples from metastatic colorectal cancer patients who did not respond to the combination therapy with bevacizumab-irinotecan-5FU in comparison to patients who were responders and developed a stable disease. Many apoptosis-related proteins possess a dual function (pro- and anti-apoptotic) due to alternative splicing. Therefore we aimed to find possible apoptosis-associated EZH2 targets to explain these interesting findings.
Methods: HCT116 colon cancer cells were used for DZNep and 5FU treatment and its efficiency was verified by Western blot analysis. In vivo splicing assay was performed using BclX minigene construct. The mRNA expression of EZH2, caspase 2, Death-associated protein kinase (DAPK) and BclX isoforms was assessed by quantitative real-time PCR in cells (BclX also in blood of patients) and normalized to the GAPDH. Cell viability was examined by Crystal Violet staining.
Results: Western Blot for caspase 3 cleavage indicated increased apoptotic levels after DZNep treatment. Combined DZNep and 5FU treatment of cells led to a synergistic effect in reducing cell viability. DZNep treatment specifically promoted pro-apoptotic BclXs isoform, but did not affect the shift of pro-apoptotic isoforms of caspase 2 and DAPK. Using a BclX minigene transfection we confirmed this effect exogenously. The ratio BclXs/Xl was significantly altered by overexpression of different splicing factors such as ASF/SF2, Sam68, after DZnep treatment. Moreover, patients who did not respond to the combination therapy had the highest EZH2 and BclXl isoform levels.
Conclusion: Our data indicate a new interesting link between epigenetic regulation and the splicing machinery. Detailed investigation of EZH2-mediated regulation of BclXs/Xl ratio could have the potential for prediction of 5FU-based therapy response in colon cancer patients.
Citation Format: Natalya Benderska, Maria Gazouli, Gerasimos Aravantinos, Arndt Hartmann, Regine Schneider-Stock. Response to 5FU therapy in colorectal cancer is affected by EZH2-mediated BclX splicing. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2769.
Abstract 2785: The role of heat shock factors for cancer stem cell regulation
Authors: Thakkar Ankita , Wang Bin , Ince Tan A. 
Published: July 2016

Abstract
Introduction: Heat shock factor family is a group of transcription factors that can bind specifically to heat shock elements (HSE) within the promoter region of heat shock protein (HSP). The HSF pathway activation helps cells survive under stress by preventing protein misfolding and aggregation. Three heat shock factors (HSF1, HSF2 and HSF4) have been identified in humans, among them, HSF1, which is believed to be the master regulator of cellular response to stress, is by far the best-characterized member of the HSF family.
We first identified that high HSF1 is associated with high tumor grade and poor survival in multiple cancer models including breast, ovarian, lung and colon cancers. In addition, our recent data indicate that HSF1 drives a distinct transcription program that is unrelated to heat shock response in malignant tumors, and this HSF1 “non-heat shock related transcription program” correlates with poor outcome in breast cancer patients. Moreover, we confirmed that HSF1 drives the Cancer Stem Cell (CSC) phenotype in multiple breast cancer cell lines and facilitate chemo-treatment resistance by increasing CSC frequency in breast cancer cells.
Previous studies have shown that HSF2 and HSF4 may play a role in cancer progression either on their own or through interaction with HSF1. HSF2 forms hetero-trimers with HSF1 and facilitate its function in response to heat shock. Inactivation of HSF4 in p53 null mouse models causes cell senescence and suppression of tumorigenesis, with great similarities to HSF1-/- p53 null mice.
Results: In an attempt to investigate how HSF1 is activated to regulate CSC phenotype, we constructed phospho HSF1 at three different sites. We observed that there is no correlation of phospho activation of HSF1 with CSC phenotype. In follow-up work to the studies above, we found that both HSF2 and HSF4 are also significantly up-regulated in CSCs, suggesting that they may cooperate with HSF1 in regulating CSCs. Moreover, we discovered that HSF4 is over-expressed in breast cancers compared to normal mammary gland, and over-expression of HSF4 induces tumorsphere formation in breast cancer cells.
Conclusion: These observations indicated that in order to gain a complete understanding of the role of the HSFs in cancer it is now necessary to study all three HSFs together.
Citation Format: Ankita Thakkar, Bin Wang, Tan A. Ince. The role of heat shock factors for cancer stem cell regulation. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2785.
Abstract 2795: MARVELD1 regulates hypoxia-induced oxidative stress response and tumor growth
Authors: Shi Ming , Yao Yuanfei , Li Yu 
Published: July 2016

Abstract
Nuclear factor MARVELD1 (MARVEL domain-containing 1) is a potential tumor suppressor, which negatively regulates tumor cell proliferation. It is widely expressed in human normal tissues, but down-regulated in multiple primary carcinomas. In this study, we show that MARVELD1 acts as tumor suppressor via its ability to inhibit reative oxygen species (ROS) in response to hypoxic condition. Data showed that overexpression of MARVELD1 in uterine cancer cells significantly suppressed tumor growth, while MARVELD1 silencing promoted colony formation of tumor cells in hypoxic environment. Furthermore, we found that ROS production in hypoxia-treated cancer cells was elevated by MARVELD1 silencing. Mitochondria function assay showed that compared to RL952/vector cells, a decrease in oxygen consumption and derived mitochondrial ATP production was observed in hypoxia-treated RL952/MARVELD1 cells. Moreover, considering that ROS that induced by hypoxia promoted tumor cell proliferation, our data further indicated ROS generation that inhibited by MARVELD1 alleviated the growth of uterine tumor cells. Taken together, MARVELD1 regulated hypoxia-induced oxidative stress response and cell growth through inhibiting ROS generation in uterine cancer, suggesting that targeting MARVELD1 might be a novel strategy to cancer therapy.
Keywords: MARVELD1, Hypoxia, Oxidative stress, ROS
Citation Format: Ming Shi, Yuanfei Yao, Yu Li. MARVELD1 regulates hypoxia-induced oxidative stress response and tumor growth. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2795.