bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract A10: Fatty acid synthesis inhibitor, orlistat, potentiates cisplatin-induced toxicity in ovarian cancer cells
Authors: Houten Bennett Van , Heft-Neal Molly , Qian Wei , Roginskaya Vera 
Published: August 2018

Abstract
Background: Fatty acid synthase (FAS) is a key enzyme in the synthesis of fatty acids and has been shown to be upregulated in many cancers. Additional studies found that high levels of FAS correlated with worse prognosis and with chemoresistance in ovarian tumors. As such, FAS has become a promising target for antitumor therapies. The aim of this study was to gain mechanistic insights into the cytotoxic effects of fatty acid inhibition with orlistat treatment alone or in combination with cisplatin in the ovarian cancer cell line A2780.
Methods: A2780 cells were treated with cisplatin (0.4-12 μM) for 4 hours followed by orlistat (25-100 μM, 24 hr). Cell proliferation was measured via CyQuant assay; cell apoptotic activity was measured by both caspase 3/7 assay and flow cytometry with annexin V and propidium iodide. Fatty acid β-oxidation was then characterized using a Seahorse XF24 Extracellular Flux Analyzer. ATP levels were measured with a luminescent ATP detection kit. Finally, Western blot analyses for capsase 3 and phospho-ATM were performed.
Results: Cisplatin treatment (4 and 10 μM) of A2780 cells induced an increase in OXPHOS and steady-state levels of ATP 24 hr after damage. Orlistat (25 and 50 μM, 24 hr) decreased basal oxygen consumption and decreased steady-state ATP levels in cisplatin-treated cells. A2780 cells showed decreased proliferation and increased apoptotic activity (Caspase 3/7 and Annexin V) when treated with cisplatin followed by orlistat, as compared to either drug alone. Using the Chou Talaly method the combination index was found to be 0.73 indicating a synergistic relationship. Cisplatin increased the level of phospho-ATM that was reduced by orlistat.
Conclusions: Orlistat in combination with cisplatin treatment of A2780 ovarian tumor cells increased apoptosis compared to either treatment alone. Orlistat caused decreased oxidative phosphorylation and prevented a cisplatin-induced increase in OXPHOS and ATP. The combination of cisplatin and orlistat decreases p-ATM, suggesting decreased activation of the DNA repair pathway after cisplatin treatment. This may represent the mechanism of synergistic action of the combination treatment.
Citation Format: Bennett Van Houten, Molly Heft-Neal, Wei Qian, Vera Roginskaya. Fatty acid synthesis inhibitor, orlistat, potentiates cisplatin-induced toxicity in ovarian cancer cells. [abstract]. In: Proceedings of the AACR Conference: Addressing Critical Questions in Ovarian Cancer Research and Treatment; Oct 1-4, 2017; Pittsburgh, PA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(15_Suppl):Abstract nr A10.
Abstract A16: COL11A1 confers cisplatin resistance through fatty acid oxidation in ovarian cancer cells
Authors: Rada Miran , Cha Jennifer , Sage Jessica , Zhou Bo , Yang Wei , Orsulic Sandra , Cheon Dong-Joo 
Published: August 2018

Abstract
Cisplatin resistance is the major challenge in the treatment of ovarian cancer, and it is crucial to develop novel therapeutic strategies to block cisplatin resistance. The purpose of this study was to identify new therapeutic targets for the treatment of cisplatin-resistant ovarian cancer.
We previously identified collagen type XI alpha 1 (COL11A1) as a novel biomarker associated with cisplatin resistance in ovarian cancer. COL11A1 is expressed by cancer-associated fibroblasts (CAFs) adjacent to cancer cells as well as cisplatin-resistant ovarian cancer cell lines. Our data indicate that COL11A1 inhibits cisplatin-induced apoptosis in ovarian cancer cells, but not through altered gene expression of many of the well-established mechanisms of cisplatin resistance (i.e., transport, inactivation, DNA repair pathways). Rather, our proteomics data revealed that mitochondrial fatty acid beta-oxidation (FAO) was the most upregulated pathway by COL11A1 in ovarian cancer cells. To determine a link between COL11A1-driven cisplatin resistance and FAO, we knocked down COL11A1 in A2780CIS cisplatin-resistant ovarian cancer cells, a cell line expressing high endogenous levels of COL11A1. COL11A1 knockdown not only decreased the expression of genes involved in fatty acid beta-oxidation, such as CD36, CPT1A, ACAA2, HADHA, but also decreased fatty acid oxidation rate and increased cisplatin-induced apoptosis in A2780CIS ovarian cancer cells. In contrast, ovarian cancer cells became resistant to cisplatin-induced apoptosis and increased fatty acid beta-oxidation when exposed to COL11A1 protein or cocultured with COL11A1-overexpressing CAFs. Importantly, these cancer cells became more sensitive to the FAO inhibitor etomoxir.
Collectively, our results suggest that COL11A1 confers cisplatin resistance by increasing FAO in ovarian cancer cells. Our study uncovers FAO as a promising therapeutic target to reduce cisplatin resistance in ovarian cancer, particularly in recurrent ovarian cancers that typically express high levels of COL11A1.
Citation Format: Miran Rada, Jennifer Cha, Jessica Sage, Bo Zhou, Wei Yang, Sandra Orsulic, Dong-Joo Cheon. COL11A1 confers cisplatin resistance through fatty acid oxidation in ovarian cancer cells. [abstract]. In: Proceedings of the AACR Conference: Addressing Critical Questions in Ovarian Cancer Research and Treatment; Oct 1-4, 2017; Pittsburgh, PA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(15_Suppl):Abstract nr A16.
Abstract A35: Ovarian cancer stem cells subvert tumor-specific T cells by disrupting T cells’ metabolic fitness
Authors: Qian Feng , Liao Jianqun , Miliotto Anthony J. , Collins Katherine A. , Odunsi Kunle 
Published: August 2018

Abstract
Cancer stem cells (CSCs) are defined by their unlimited self-renewal ability and their capacity to initiate and maintain malignancy, traits that are not found in most cells that compose the tumor. These stem cells have been shown to be relatively resistant to conventional chemotherapeutic regimens and radiation. Previously, we have reported that spheroid cells derived from 3D epithelial ovarian cancer cells are enriched with cancer stem cells by in vitro and in vivo experiments. In addition, we have demonstrated that CSCs adopt unique metabolic pathways by routing glucose predominantly to anaerobic glycolysis and pentose cycle to the detriment of rerouting glucose for anabolic purposes. In the current study, we hypothesized that CSCs may contribute to the immunosuppressive microenvironment of ovarian cancer by disrupting the metabolic fitness of infiltrating T cells. We isolated fresh spheroid cells from ovarian cancer patients’ ascites and examined their effect on T-cell responses ex vivo. In addition, other than ovarian cancer, we generated more spheroid cells from pancreatic cancer and breast cancer cells. Compared to nonspheroid cells, these spheroid cells have upregulated stem cell gene expression, higher ALDH activity, and more tumor-initiating capacities in SCID mice, indicating CSCs enrichment in spheroid cells. Seahorse XF analysis revealed a glycolytic metabolic phenotype of spheroid cells with increased extracellular acidification rate (ECAR) compared to nonspheroid cells. Spheroid cells suppress the response of cocultured T cells to TCR stimulation by inhibiting T-cell activation, growth, proliferation, and function independent of cell-cell contact determined by transwell assay and supernatant incubation. After spheroid cells treatment, activated T cells metabolically shifted from energetic to quiescence phenotype, which is reversely correlated with increased glycolysis in spheroid cells, indicating that highly glycolytic spheroid cells suppress T-cell response through reprogramming T-cell metabolic status. Furthermore, we found that spheroid cells dampen T cells’ response by inhibiting Erk-AKT-mTor signaling and by activating the integrated stress response pathway. This study provides novel insights into the relationship between cancer stem cells and T cells’ response and has clinical implications for cancer therapy.
Citation Format: Feng Qian, Jianqun Liao, Anthony J. Miliotto, Katherine A. Collins, Kunle Odunsi. Ovarian cancer stem cells subvert tumor-specific T cells by disrupting T cells’ metabolic fitness. [abstract]. In: Proceedings of the AACR Conference: Addressing Critical Questions in Ovarian Cancer Research and Treatment; Oct 1-4, 2017; Pittsburgh, PA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(15_Suppl):Abstract nr A35.
Abstract A40: Specific mutations in the D1-D2 linker region of VCP/p97 enhance ATPase activity and confer resistance to VCP inhibitors
Authors: Bastola Prabhakar , Freudenthal Bret , Schaich Matthew , Chou Tsui-Fen , Gan Taiping , Wang Feng , Chien Jeremy 
Published: August 2018

Abstract
Valosin-containing protein (VCP) has been shown to be involved in various protein quality control pathways including ubiquitin proteasome system, endoplasmic reticulum-associated degradation, chromatin-associated degradation, protein aggregate processing, and autophagy. Recent studies also identified VCP as a lineage-specific essential gene in ovarian cancer. An orally bioavailable VCP inhibitor, CB-5083, is currently in phase I clinical trials because it shows therapeutic effects in multiple tumor xenograft models. However, the mechanism of resistance to CB-5083 is unknown. Here, we characterized molecular mechanism of resistance to CB-5083. Using incremental exposure to CB-5083, we established CB-5083-resistant ovarian cancer cells that showed 5-6 fold resistance in vitro compared to parental cells. Genomic and complementary DNA sequencing of the VCP coding region reveal a pattern of coselected mutations: (1) missense mutations at codon 470 in one copy resulting in increased ATPase activity and (2) nonsense or frameshift mutations at codon 606 or codon 616 in another copy causing the loss of allele-specific expression. Unbiased molecular docking studies show codon 470 as a putative binding site for CB-5083. Analysis of somatic mutations in cancer genomes from The Cancer Genome Atlas indicates that codon 616 contains hotspot mutations in VCP. Thus, identification of these mutations associated with in vitro resistance to VCP inhibitors may be useful as potential theranostic markers while screening for patients to enroll in clinical trials. VCP has emerged as a viable therapeutic target for several cancer types, and therefore targeting such hyperactive VCP mutants should aid in improving the therapeutic outcome in cancer patients.
Citation Format: Prabhakar Bastola, Bret Freudenthal, Matthew Schaich, Tsui-Fen Chou, Taiping Gan, Feng Wang, Jeremy Chien. Specific mutations in the D1-D2 linker region of VCP/p97 enhance ATPase activity and confer resistance to VCP inhibitors. [abstract]. In: Proceedings of the AACR Conference: Addressing Critical Questions in Ovarian Cancer Research and Treatment; Oct 1-4, 2017; Pittsburgh, PA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(15_Suppl):Abstract nr A40.
Abstract A63: Estrogen receptor signaling in fallopian tube epithelia of BRCA mutation carriers
Authors: Dodds Leah V. , Nelson Omar , Shaw Patricia , Milea Anca , Sowamber Ramlogan , George Sophia HL 
Published: August 2018

Abstract
Background: The most common and aggressive type of epithelial ovarian cancers (EOC) is high-grade serous carcinoma (HGSC), which accounts for 90% of ovarian cancer deaths. HGSC is the predominant histotype associated with BRCA1 and BRCA2 mutations. Prophylactic surgery in BRCA mutation carriers has implicated the fallopian tube epithelium (FTE), a hormonal responsive tissue, as the etiologic site of origin for HGSC. Estrogen and its receptors are major regulators of growth and differentiation in normal ovaries and fallopian tubes, and its mutagenic properties have been linked to ovarian carcinogenesis. Estrogen receptors (ER) are rarely mutated, amplified, or deleted in HGSC, yet only 10% of patients respond to antiestrogen treatment. TP53 mutations in the form of the p53 signature have been found in serous tubal intraepithelial carcinomas (STIC) and are ubiquitously present in patients with HGSC. We hypothesized that in the presence of dysfunctional p53, subsequent promiscuous binding of ER will yield aberrant signaling, contributing to cellular transformation.
Methods: We used our previously published gene expression profiles to generate a candidate gene list, which was chosen based on the presence of known estrogen-responsive elements. We analyzed expression of 6 ER responsive genes using data collected from laser capture microdissection in normal FTE tissues. Tissue microarray analysis (TMA) was also performed on a subset of HGSC tumor samples from this cohort, staining for PR, ER, and p53, and expression was analyzed alongside their respective outcome and overall survival Finally, to mimic the in vivo environment of early carcinogenesis, FTE-normal and FTE-p53 mutant cell lines were established and treated with 100nM estradiol, an estrogen analog, to observe changes in response.
Results: Preliminary data showed that FTE-BRCA and FTE-nonBRCA seemingly look and express ER and PR proteins similarly. Underlying these morphologic similarities is a potential haploinsufficiency predisposing FTE-BRCA to cytotoxic stresses. Microarray gene expression of laser captured FTE-BRCA and FTE-nonBRCA showed varied levels of ER mRNA expression across samples (n=25) while PR transcript levels change dynamically. The data generated have facilitated the development of gene signatures and biomarkers that will predict response to antiestrogen therapy and identify patients who will benefit from hormonal therapies.
Citation Format: Leah V. Dodds, Omar Nelson, Patricia Shaw, Anca Milea, Ramlogan Sowamber, Sophia HL George. Estrogen receptor signaling in fallopian tube epithelia of BRCA mutation carriers. [abstract]. In: Proceedings of the AACR Conference: Addressing Critical Questions in Ovarian Cancer Research and Treatment; Oct 1-4, 2017; Pittsburgh, PA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(15_Suppl):Abstract nr A63.
Abstract A65: Combination of a thioxodihydroquinazolinone compound with cisplatin eliminates ovarian cancer stem cell-like cells (CSC-LCs) and shows preclinical potential
Authors: Ma Jing , Salamoun Joseph , Wipf Peter , Edwards Robert , Houten Bennett Van , Qian Wei 
Published: August 2018

Abstract
Cancer stem cell-like cells (CSC-LCs) contribute to drug resistance and recurrence of ovarian cancer. Strategies that can eradicate CSC-LCs are expected to substantially improve the outcome of ovarian cancer treatments. We have previously identified a class of thioxodihydroquinazolinone small molecules, which have strong synergistic antitumor activity with platinum drugs, the standard chemotherapeutic agents for ovarian cancer treatment. In the current study, using the activity of aldehyde dehydrogenase (ALDH) as a marker of CSC-LCs, we demonstrated that the combination of thioxodihydroquinazolinone compound 19 with cisplatin is able to deplete ALDH-high CSC-LC population in both established platinum-resistant ovarian cancer cell lines and primary ovarian cancer cells from metastatic ascites of a cisplatin-resistant patient. Compound 19 enhanced the accumulation of intracellular cisplatin in ALDH-high ovarian cancer cells. The combination of compound 19 with cisplatin was also able to reduce the sphere-forming capability of cisplatin-resistant ovarian cancer cells. Using a spheroid-based in vitro metastasis model of ovarian cancer, we demonstrated that the combination of compound 19 with cisplatin prevents spheroid ovarian cancer cells from attaching to substratum and spreading. In vivo, the treatment by the combination of compound 19 with cisplatin significantly reduced tumor burden in a cisplatin-resistant intraperitoneal ovarian cancer xenograft mouse model, as compared to cisplatin-alone treatment. Taken together, our study demonstrated that the thioxodihydroquinazolinone compounds are a new class of agents that in combination with cisplatin are capable of eliminating CSC-LCs in ovarian cancer. Further development of thioxodihydroquinazolinone small molecules may yield a more effective treatment for cisplatin-resistant metastatic ovarian cancer.
Citation Format: Jing Ma, Joseph Salamoun, Peter Wipf, Robert Edwards, Bennett Van Houten, Wei Qian. Combination of a thioxodihydroquinazolinone compound with cisplatin eliminates ovarian cancer stem cell-like cells (CSC-LCs) and shows preclinical potential. [abstract]. In: Proceedings of the AACR Conference: Addressing Critical Questions in Ovarian Cancer Research and Treatment; Oct 1-4, 2017; Pittsburgh, PA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(15_Suppl):Abstract nr A65.
Abstract B05: Cloning and vulnerability of intrinsically resistant subset of ovarian cancer stem cells
Authors: Chang Guoqiang , Li Jinxiu , Wang Bailiang , Yamamoto Yusuke , Mahalingam Rajasekaran , Duleba Marcin , Rao Wei , Xie Jingzhong , Wang Shan , Jazaeri Amir , Davies Peter , Torti Suzy , Draetta Giulio , Anderson Matthew , Brewer Molly , Crum Christopher , McKeon Frank , Xian Wa 
Published: August 2018

Abstract
High-grade ovarian cancer is extremely sensitive to chemotherapy and yet usually lethal due to recurrent disease. To address the underlying mechanism of chemotherapy resistance in this disease, we employed novel technology developed to clone normal adult epithelial stem cells to generate libraries of patient-specific, clonogenic tumor cells. These clones possess hallmarks of “cancer stem cells” including long-term self-renewal and recapitulation of tumors of appropriate histology in immunodeficient mice. Significantly, these clonogenic tumor cells possess the overall pattern of genomic alterations of the whole tumor and yet display clone-specific patterns of variation reflecting intratumor heterogeneity that is stable despite months of continuous propagation. Our analyses at the clonal level have revealed a subset that display an intrinsic, pretherapy resistance to paclitaxel and hypervariable genomics in contrast to the bulk of clones sampled from the library. These intrinsically resistant clones share genomic and gene expression profiles with those surviving paclitaxel treatment of the whole library, suggesting a role for intrinsically resistant cells in recurrent disease. Remarkably, known drugs that interfere with signaling pathways enriched in both intrinsically resistant and paclitaxel survivor clones are synthetically lethal with standard-of-care chemotherapy. The targeting of intrinsically resistant clones from patient-specific libraries of cancer stem cells offers new strategies for preempting recurrent disease.
Citation Format: Guoqiang Chang, Jinxiu Li, Bailiang Wang, Yusuke Yamamoto, Rajasekaran Mahalingam, Marcin Duleba, Wei Rao, Jingzhong Xie, Shan Wang, Amir Jazaeri, Peter Davies, Suzy Torti, Giulio Draetta, Matthew Anderson, Molly Brewer, Christopher Crum, Frank McKeon, Wa Xian. Cloning and vulnerability of intrinsically resistant subset of ovarian cancer stem cells. [abstract]. In: Proceedings of the AACR Conference: Addressing Critical Questions in Ovarian Cancer Research and Treatment; Oct 1-4, 2017; Pittsburgh, PA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(15_Suppl):Abstract nr B05.
Abstract B09: IGF axis plays a pivotal role in the ovulation-induced malignant transformation of fallopian tube fimbrial epithelial cells
Authors: Chu Tang-Yuan , Huang Hsuan-Shun , Hsu Che-Fang , Chen Pao-Chu 
Published: August 2018

Abstract
Owing to uncertain tissue-of-origin and elusive etiology, high-grade serous ovarian carcinoma (HGSC) is typically diagnosed at late stages with poor prognosis. Recent studies have unveiled the fallopian tube fimbria as the major tissue of origin and incessant ovulation as the main etiology, but the mechanism of cancer initiation remains elusive. In a series of studies we have found a majority of preovulatory follicular fluids (FF) contain high level of ROS that induce DNA double-strand breaks as well as apoptosis to the fimbrial epithelial cells in vitro and in vivo. We also found that hemoglobin (Hb) in pelvis, most likely contributed by retrograde menstruation of previous cycles, reduces the ovulatory ROS level extracellularly and results in a shifting from the apoptotic to the survival fate of ROS-stressed fimbrial epithelial cells. These initiating factors in FF, although they may contribute to the TP53 mutation and other early genetic hits in the genesis of HGSC, cannot fully transform the immortalized fimbrial epithelial cell lines with loss of p53 and Rb. Here we show that IGF axis proteins, including IGFBP2- and IGFBP6-bound IGFs as well as the IGFBP-lytic enzyme PAPP-A, are abundant in ovulatory FF. Upon engaging with glycosaminoglycans (GAG) on the membrane of fimbrial epithelial cells, PAPP-A cleaves IGFBPs and releases bioactive IGF in close proximity to its receptor IGF-1R. Through the PI3K/Akt/mTOR signaling pathway, the FF-derived IGF exerts transformation effects on immortalized fimbrial epithelial cells, inducing anchorage independent growth and xenograft tumorigenesis. By contrast, much less transformation was noted when IGFBP2/6 or PAPP-A was depleted from the FF, when the GAG-docking was blocked, or when IGF-1R ormTOR was inhibited. Taken together, the serial studies have unveiled multiple cancer initiating factors in ovulation and retrograde menstruation where ROS acts as the mutagen, hemoglobin serves as the surviving rescuer, and the IGF axis acts as the main transforming signal.
Citation Format: Tang-Yuan Chu, Hsuan-Shun Huang, Che-Fang Hsu, Pao-Chu Chen. IGF axis plays a pivotal role in the ovulation-induced malignant transformation of fallopian tube fimbrial epithelial cells. [abstract]. In: Proceedings of the AACR Conference: Addressing Critical Questions in Ovarian Cancer Research and Treatment; Oct 1-4, 2017; Pittsburgh, PA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(15_Suppl):Abstract nr B09.