bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 2477: Genomic instability in BRCA1-deficient cells is a result of the anti-recombinogenic activity of BLM helicase
Authors: Patel Dharm S. , Misenko Sarah M. , Bunting Samuel F.
Published: July 2017

Mutations in BRCA1 are responsible for approximately 5% of cases of breast cancer, and there are few treatment options that substantially alter the probability of disease onset in individuals with BRCA1 mutations. BRCA1-deficient cells exhibit increased genomic instability following DNA damaging treatments due to a defect in the homologous recombination (HR) DNA repair pathway. Presently, Olaparib, a PARP inhibitor, is approved as a targeted monotherapy for germline BRCA1 mutated advanced ovarian cancers. As use of this treatment has expanded, data suggests that patients exhibit a further relapse and resistance to PARP inhibitors via mechanisms that include the development of secondary BRCA1 reversion mutations, enhanced drug efflux relating to P-glycoprotein, and mutations in other DNA repair proteins that restore HR. Here, we show that the RECQ helicase, BLM, mediates the genomic instability observed in BRCA1-deficient cells by a mechanism that depends in part on its anti-recombinogenic activity. We have generated conditional knockout mice with single and combined deficiencies in BRCA1, BLM, and 53BP1 in the B lymphocyte cell population. Ablation of BLM in BRCA1-deficient cells allows the HR repair pathway to be restored, leading to a partial rescue of the genomic instability that is present in BRCA1-deficient cells. The stable accumulation of RAD51, a marker for HR, at DNA double-strand break sites is inhibited by BLM in BRCA1-deficient B cells. However, DNA end resection is not impacted by single or co-deletion of BRCA1 and BLM. Furthermore, cells co-deficient in BRCA1 and BLM display limited sensitivity to PARP inhibition. The rescue in HR and PARPi sensitivity phenotypes following deletion of BLM is only present in hypomorphic BRCA1Δ11/Δ11 cells and not the RING domain deficient BRCA1Δ2/Δ2. These results demonstrate that the anti-recombinogenic activity of BLM is of potentially great significance for regulating the balance of HR versus other error-prone repair pathways. Mutation of BLM in BRCA1-deficient tumors is therefore a potential pathway leading to resistance to PARPi and other DNA damaging agents.

Citation Format: Dharm S. Patel, Sarah M. Misenko, Samuel F. Bunting. Genomic instability in BRCA1-deficient cells is a result of the anti-recombinogenic activity of BLM helicase [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2477. doi:10.1158/1538-7445.AM2017-2477
Abstract 2480: Suppression of homology-dependent DNA double-strand break repair induces PARP inhibitor sensitivity in VHL-deficient human renal cell carcinoma
Authors: Scanlon Susan E. , Sulkowski Parker L. , Glazer Peter M.
Published: July 2017

The von Hippel-Lindau (VHL) tumor suppressor gene is inactivated in the vast majority of human clear cell renal carcinomas. The pathogenesis of VHL loss is currently best understood to occur through stabilization of the hypoxia-inducible factors, activation of hypoxia-induced signaling pathways, and transcriptional reprogramming towards a pro-angiogenic and pro-growth state. However, hypoxia also drives other pro-tumorigenic processes, including the development of genomic instability via down-regulation of DNA repair gene expression. Here, we find that DNA repair genes involved in double-strand break repair by homologous recombination (HR) and in mismatch repair, which are down-regulated by hypoxic stress, are decreased in VHL-deficient renal cancer cells relative to wild type VHL-complemented cells. Non-homologous end joining (NHEJ) genes are not decreased in VHL-deficient cells, demonstrating specificity of the down-regulation and similarity to hypoxia. Functionally, this repression of HR genes is associated with impaired DNA double-strand break repair in VHL-deficient cells, as determined by the persistence of ionizing radiation-induced DNA double-strand breaks and reduced activity in a homology-dependent plasmid reactivation assay. Furthermore, VHL deficiency conferred increased sensitivity to the DNA crosslinking agent mitomycin C and PARP inhibitors, analogous to the synthetic lethality observed between hypoxia and these chemotherapeutic agents. Finally, we discovered a correlation between VHL inactivation and reduced HR, but not NHEJ, gene expression in a large panel of human renal carcinoma samples. Together, our data elucidate a novel connection between VHL-deficient renal carcinoma and hypoxia-induced down-regulation of DNA repair, and identify potential opportunities for targeting DNA repair defects in human renal cell carcinoma.

Citation Format: Susan E. Scanlon, Parker L. Sulkowski, Peter M. Glazer. Suppression of homology-dependent DNA double-strand break repair induces PARP inhibitor sensitivity in VHL-deficient human renal cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2480. doi:10.1158/1538-7445.AM2017-2480
Abstract 249: Dietary supplementation with methylseleninic acid reduces male mammary tumorigenesis in MMTV-PyMT mice
Authors: Sundaram Sneha
Published: July 2017

Male breast cancer makes up approximately 1% of all breast cancers and less than 1% of all cancers in men in the United States. However, it is an aggressive disease with poor prognosis and the incidence of male breast cancer is on the rise. The present study investigated the effects of dietary supplementation of selenium on male breast carcinogenesis in MMTV-PyMT mice (FVB/N background). Three-week-old male mice were weaned onto the AIN93G diet with or without supplementation of selenium in the form of methylseleninic acid (2.5 mg Se/kg). Mice were euthanized 10 weeks after the first palpable mammary tumor was detected. There were no differences in food intake and body weight between the groups. The median latency (the age at which the first palpable tumor was detected) was 14.1 and 13.9 weeks and the incidence of palpable mammary tumor was 71% and 70% for the control and the selenium group, respectively. Selenium supplementation compared to the control diet reduced mammary tumor progression by 258% and tumor weight by 84%, respectively. Tumor progression was defined as the change in tumor volume from detection of the first palpable mammary tumor to termination 10 weeks later. Incidence of lung metastasis was 74% and 50% in control and selenium group, respectively. In mice bearing lung metastases, selenium supplementation significantly reduced the number of metastases by 83% compared to the control group. In conclusion, dietary supplementation with selenium in the form of methylseleninic acid reduces male breast carcinogenesis and its metastasis in mice. It indicates that selenium may be useful in male breast cancer prevention.

Citation Format: Sneha Sundaram. Dietary supplementation with methylseleninic acid reduces male mammary tumorigenesis in MMTV-PyMT mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 249. doi:10.1158/1538-7445.AM2017-249
Abstract 2496: Targeting brain tumor stem cells by interfering with choline metabolism: Evidence for an EMT-choline oncometabolic network
Authors: Koch Katharina , Hartmann Rudolf , Suwala Abigail K. , Rios Dayana Herrera , Kahlert Ulf D. , Maciaczyk Jaroslaw
Published: July 2017

Glioblastoma (GBM) is the most lethal primary malignant brain tumor with a median survival of less than two years. High levels of therapy resistance, strong cellular invasiveness and rapid cell growth demand aggressive multimodal therapies involving resection as well as radio-chemotherapy. Recent evidence has pointed to the existence of brain tumor stem cells (BTSCs), a subpopulation of human brain tumors which is thought to be responsible for tumor dissemination, relapse and chemo resistance. BTSCs have been associated with the expression of mesenchymal features as a result of epithelial-mesenchymal transition (EMT). Using high resolution proton nuclear magnetic resonance spectroscopy (1H NMR) we compared the intracellular metabolic composition of GBM cells after induction vs. inhibition of EMT as well as under stem cell or differentiated conditions. We identified that both EMT and enrichment for stemness induces the cholinic phenotype which is characterized by high intracellular levels of phosphocholine and total choline derivatives. Furthermore, interference with choline metabolism by targeting choline kinase alpha (CHKα) reversed EMT in GBM cells as we observed reduced invasiveness, clonogenicity, and expression of EMT associated genes. Taken together, interfering with choline metabolism is a powerful strategy to suppress EMT and thus target BTSCs. Moreover, the newly identified BTSC-oncometabolic network could be used to non-invasively monitor the invasive properties of glioblastomas and the success of anti-BTSC therapy.

Citation Format: Katharina Koch, Rudolf Hartmann, Abigail K. Suwala, Dayana Herrera Rios, Ulf D. Kahlert, Jaroslaw Maciaczyk. Targeting brain tumor stem cells by interfering with choline metabolism: Evidence for an EMT-choline oncometabolic network [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2496. doi:10.1158/1538-7445.AM2017-2496
Abstract 2501: Assessing metabolic activity of patient-derived models of non-small cell lung cancer using stable isotope resolved metabolomics (SIRM)
Authors: Kinslow Connor J. , Tan Jinlian , Cai Yihua , Yan Jun , Higashi Richard M. , Lane Andrew N. , Fan Teresa W.
Published: July 2017

Stable Isotope-Resolved Metabolomics (SIRM) has been a useful tool in interrogating metabolic reprogramming in cancer. We have recently published several protocols using SIRM in patient-derived models of non-small cell lung cancer (NSCLC)1. In this case study, we compared central metabolic activity in three different model systems, all derived from the same patient. Slices from the human tumor (Warburg slices 2,3), slices from an NSG mouse bearing the human tumor 4, and the patient-derived cell culture were incubated in [U-13C]-glucose or [U-13C,15N]-glutamine for 24 hours. Samples were then harvested and analyzed by gas-chromatography-mass spectrometry and NMR. All three models displayed similar levels of fractional enrichment after 24 hours, making metabolic comparison possible, despite their very different 3D architectures. Glucose metabolism in particular, showed consistent labeling patterns of metabolites in glycolysis and the Krebs cycle. Glutamine metabolism, however, was distinct in the cell culture, with a pattern that indicated upregulation of anaplerotic glutaminolysis. Activation of glutaminolysis may be an important transformative step in the establishment of a viable cell culture. We are also in the process of validating the present finding by comparing multiple patient-derived models of NSCLC and tracking the evolution of their metabolic activity.

1 Lane, A. N., Higashi, R. M. & Fan, T. W.-M. Preclinical models for interrogating drug action in human cancers using Stable Isotope Resolved Metabolomics (SIRM) Metabolomics 12, 1-15 (2016).

2 Fan, T. W.-M. et al. Distinctly perturbed metabolic networks underlie differential tumor tissue damages induced by immune modulator β-glucan in a two-case ex vivo non-small cell lung cancer study. CSH Molec. Case Studies J. 2, a00083, (2016).

3 Fan, T. W.-M., Lane, A. N. & Higashi, R. M. Stable Isotope Resolved Metabolomics Studies in ex vivo Tissue Slices. Bio-protocol 6, e1730 (2016).

4 Lane, A. N., Yan, J. & Fan, T. W.-M. 13C Tracer Studies of Metabolism in Mouse Tumor Xenografts. Bio-protocol 5, e1650 (2015).

Citation Format: Connor J. Kinslow, Jinlian Tan, Yihua Cai, Jun Yan, Richard M. Higashi, Andrew N. Lane, Teresa W. Fan. Assessing metabolic activity of patient-derived models of non-small cell lung cancer using stable isotope resolved metabolomics (SIRM) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2501. doi:10.1158/1538-7445.AM2017-2501
Abstract 2502: Liquid diet introduction of tracers into mice for stable isotope-resolved metabolomics (SIRM) investigations
Authors: Sun Ramon C. , Warmoes Marc O. , Yang Ye , Deng Pan , Sun Qiushi , Lane Andrew N. , Higashi Richard M. , Fan Teresa W-M
Published: July 2017

Tracer-based mapping of metabolic networks in vivo is a powerful approach for revealing metabolic reprogramming in human cancer. However, current in vivo labeling techniques for model animals face important challenges including insufficient depth of pathway coverage (e.g. inability to detect labeled nucleotides, proteins, and lipids) and stress-related artifacts. Here, we report stress-free administration of 13C6-glucose via liquid diet into mice. 13C enrichment was observed in metabolites of glycolysis, the Krebs cycle, the pentose phosphate pathway, nucleobases, UDP-sugars, as well as macromolecules glycogen, lipids, and proteins from major organs in NSG mice. We have applied the liquid diet method to map the glucose metabolic networks in NSCLC tumors in a patient-derived xenograft (PDX) model. We observed a high enrichment in the metabolites of glycolysis, Krebs cycle, and PPP as well as de novo synthesized nucleotides and amino acids by IC-UHR-FTMS analysis. Lung PDX displayed unexpected metabolic complexity, such as the use of pyruvate to fuel anaplerosis as well as gluconeogenesis. We also found high 13C enrichment in both tumor and plasma glutamine, which implies that glutamine in the PDX tumors largely came from other organs via the blood rather than being synthesized in situ. Our data showed that liquid diet is an effective and noninvasive means for comprehensive analysis of glucose-associated metabolic networks in human tumor xenografts, which can also be extended to SIRM studies with other fuel sources.

Acknowledgements: This work was supported in part by grants: 1R01ES022191-01 (to TWMF and RMH), 1P01CA163223-01A1 (to ANL and TWMF), and 1U24DK097215-01A1 (to RMH, TWMF, and ANL)

R.C. Sun was supported by a T32 training grant to M. Vore (5T32ES007266-25)

Citation Format: Ramon C. Sun, Marc O. Warmoes, Ye Yang, Pan Deng, Qiushi Sun, Andrew N. Lane, Richard M. Higashi, Teresa W-M Fan. Liquid diet introduction of tracers into mice for stable isotope-resolved metabolomics (SIRM) investigations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2502. doi:10.1158/1538-7445.AM2017-2502
Abstract 2507: Using 1H NMR metabolomics to study breast cancer and endothelial cell metabolic interactions
Authors: Acevedo-Acevedo Suehelay , Palecek Sean P.
Published: July 2017

Breast cancer is the second most commonly diagnosed cancer among women worldwide. Patient death is typically caused by metastasis development rather than the primary tumor. Metastasis in breast cancer has been shown to occur via blood and lymphatic vessels. Research shows that breast cancer cells ‘educate’ lymphatic and blood endothelial cells to support tumor growth by stimulating growth factor secretion; specifically VEGF, PDGF-BB and EGF secretion. In addition, cell metabolism is altered during malignant transformation. Cancer cells have increased energy and macromolecule biosynthesis requirements to sustain rapid proliferation. Increased angiogenesis observed in tumors points to a need for an increased nutrient supply. However, it remains unclear how tumor endothelial cell metabolism is altered and how metabolism regulates tumor angiogenesis. Therefore, this study aims to use 1H NMR metabolomics to identify breast cancer-endothelial cell metabolic interactions in a high-throughput manner. Firstly, we studied if in vitro co-culture with breast cancer altered endothelial cell metabolism. We identified distinct metabolic profiles for HUVECs grown in monoculture or co-culture with three different breast cancer cell lines. Metabolism of HUVECs co-cultured with MCF7 and SKBR3 breast cancer cell lines was significantly altered compared to mono-culture control. The most impacted metabolic pathways by co-culture were amino acid metabolism, energy metabolism and lipid biosynthesis pathways. Culturing HUVECs with MDA-MB-231 triple negative breast cancer cells did not have a significant impact on HUVEC metabolism, however. Together, these results indicate that culturing HUVECs with certain breast cancer lines causes significant changes in endothelial metabolism. Alterations in endothelial cell metabolism in response to breast cancer co-culture can further our understanding of tumor-vascular interactions and may lead to identification of metabolic biomarkers or therapeutic targets that can disrupt tumor angiogenesis.

Citation Format: Suehelay Acevedo-Acevedo, Sean P. Palecek. Using 1H NMR metabolomics to study breast cancer and endothelial cell metabolic interactions [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2507. doi:10.1158/1538-7445.AM2017-2507
Abstract 2511: The role of lipids metabolism in bladder cancer
Authors: Wang Gang , Cao Rui , Ge Qiangqiang , Xiao Yu , Wang Xinghuan
Published: July 2017

Bladder cancer (BCa) is one of the most common malignancy of the urinary tract. Many risk factors for BCa has been demonstrated, including aging, smoking, exposure to chemicals, dietary total cholesterol intake, dietary fatty acids intake, etc. In order to investigate the role of lipids metabolism in bladder cancer, we collected several human BCa tissues and normal bladder tissues to generate an affected pathway network by microarray analysis, and it revealed that glycerolipid metabolism, fatty acid degradation and fatty acid biosynthesis have a close correlation with bladder cancer. Therefore, Simvastatin, one of the 3-hydroxy-3-methyl glutaryl coenzyme A (HMG-CoA) reductase inhibitors, have been well-known regarding its effects on rate-limiting step in cholesterol synthesis, was used to treat with BCa cells. We observed that simvastatin could reduce BCa cell proliferation, induce cell cycle arrest at G0/G1 phase and inhibit cell metastasis. Then, the potential alterations of lipids metabolism in bladder cancer cells after simvastatin treatment was investigate by lipidomics analysis. These foundings demonstrate that lipids metabolism plays important role in bladder cancer and some lipids or related enzymes may be the novel targets for bladder cancer treatment.

Note: This abstract was not presented at the meeting.

Citation Format: Gang Wang, Rui Cao, Qiangqiang Ge, Yu Xiao, Xinghuan Wang. The role of lipids metabolism in bladder cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2511. doi:10.1158/1538-7445.AM2017-2511
Abstract 2514: Tetra-O-methyl nordihydroguaiaretic acid (M4N) broadly suppresses cancer metabolism and synergistically induces strong anticancer activity in combination with etoposide, rapamycin and UCN-01
Authors: Kimura Kotohiko , Huang Ru Chih C.
Published: July 2017

The ability of Tetra-O-methyl nordihydroguaiaretic acid (M4N) to induce rapid cell death in combination with Etoposide, Rapamycin, or UCN-01 was examined in LNCaP cells, both in cell culture and animal experiments. Mice treated with M4N drug combinations with either Etoposide or Rapamycin showed no evidence of tumor and had a 100% survival rate 100 days after tumor implantation. By comparison all other vehicles or single drug treated mice failed to survive longer than 30 days after implantation. This synergistic improvement of anticancer effect was also confirmed in more than 20 cancer cell lines. In LNCaP cells, M4N was found to reduce cellular ATP content, and suppress NDUFS1 expression while inducing hyperpolarization of mitochondrial membrane potential. M4N-treated cells lacked autophagy with reduced expression of BNIP3 and ATG5. To understand the mechanisms of this anticancer activity of M4N, the effect of this drug on three cancer cell lines (LNCaP, AsPC-1, and L428 cells) was further examined via transcriptome and metabolomics analyses. Metabolomic results showed that there were reductions of 26 metabolites essential for energy generation and/or production of cellular components in common with these three cell lines following 8 hours of M4N treatment. For instance, among the amino acids, the content of aspartate, a key metabolite in electron transport system in the mitochondria, was specifically suppressed by M4N. Deep RNA sequencing analysis demonstrated that there were sixteen genes whose expressions were found to be modulated following 6 hours of M4N treatment similarly in these three cell lines. Six out of these 16 genes were functionally related to the 26 metabolites described above. One of these up-regulated genes encodes for CHAC1, a key enzyme affecting the stress pathways through its degradation of glutathione. In fact M4N was found to suppress glutathione content and induce reactive oxygen species production. The data overall indicate that M4N has profound specific negative impacts on a wide range of cancer metabolisms supporting the use of M4N combination for cancer treatments.

Citation Format: Kotohiko Kimura, Ru Chih C. Huang. Tetra-O-methyl nordihydroguaiaretic acid (M4N) broadly suppresses cancer metabolism and synergistically induces strong anticancer activity in combination with etoposide, rapamycin and UCN-01 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2514. doi:10.1158/1538-7445.AM2017-2514
Abstract 2516: Pokemon functions as a metabolic oncoprotein integrating glucose & lipid metabolism in hepatocellular carcinoma
Authors: Jin Yibao , Li Shangfu , Cao Deliang , Gao Dan , Liu Hongxia , Liu Feng , Wang Tiejie , Jiang Yuyang
Published: July 2017

Pokemon (also known as FBI-1 or LRF) is a proto-oncogene encoded by ZBTB7A gene. It functions as a transcription factor, playing important roles in embryonic development, cell differentiation and neoplasia. Pokemon is abnormally expressed in hepatocellular carcinoma (HCC) and may contribute to the metabolic homeostasis of HCC cells, but the mechanism of action remains to be fully understood. This study demonstrated that Pokemon may integrate glycolysis and lipid metabolism in hepatocellular carcinogenesis. Our data showed that Pokemon was upregulated in HCC cell lines and clinical samples. Ectopic expression of Pokemon stimulated HCC cell growth and proliferation in culture and tumorigenesis in nude mice. Lipid metabolomic analysis by LC/MS exhibited that in HCC cells lipogenesis was positively correlated with Pokemon expression levels, and targeted expression of Pokemon in HCC cells promoted the flux of radiolabeled glucose to lipids, including membrane phospholipids, through the aerobic glycolysis-acetyl-CoA metabolic stream. Mechanistic studies revealed that Pokemon stimulated glycolysis through activation of PKA and its mediated Raf/c-Myc pathway. In the tested HCC cells, Pokemon activated fatty acid synthase (FASN) and suppressed AMPK, an inhibitor of acetyl-CoA carboxylase α (ACC-α), stimulating fatty acid and lipid synthesis. Together our results suggest that Pokemon correlates glycolysis and lipid synthesis and thus promotes lipogenesis and hepatocellular tumorigenesis.

Note: This abstract was not presented at the meeting.

Citation Format: Yibao Jin, Shangfu Li, Deliang Cao, Dan Gao, Hongxia Liu, Feng Liu, Tiejie Wang, Yuyang Jiang. Pokemon functions as a metabolic oncoprotein integrating glucose & lipid metabolism in hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2516. doi:10.1158/1538-7445.AM2017-2516
Abstract 253: Mammary tumorigenesis causes bone loss and dietary selenium supplementation does not affect such bone loss in male MMTV-PyMT mice
Authors: Yan Lin
Published: July 2017

Cancer progression is accompanied by wasting that eventually results in cachexia characterized by significant weight loss and multi-organ functional failures. Limited clinical trials indicate that bone is adversely affected by cancer-associated wasting. To determine the effects of breast cancer on skeletal health, we performed micro-computed tomographic analysis of femurs and vertebrae collected from a recently completed study showing that dietary supplementation with selenium (methylseleninic acid, 2.5 mg Se/kg) reduced male mammary tumorigenesis in MMTV-PyMT mice. Compared to age-matched non-tumor-bearing mice (MMTV-PyMT negative), the presence of mammary tumors significantly reduced bone volume fraction, trabecular thickness and bone mineral density and increased the structure model index (an indicator of the plate- and rod-like geometry of trabecular structure) in femoral trabecular bone. Mammary tumor development did not affect vertebral trabeculae nor femoral and vertebral cortical bone, except it significantly reduced cortical bone thickness of vertebrae. There were no differences in aforementioned measurements between groups with or without selenium supplementation. In conclusion, mammary tumorigenesis causes bone loss and dietary selenium supplementation at 2.5 mg Se/kg, which is antitumorigenic, does not affect mammary tumor-associated bone loss in this male MMTV-PyMT breast cancer model.

Citation Format: Lin Yan. Mammary tumorigenesis causes bone loss and dietary selenium supplementation does not affect such bone loss in male MMTV-PyMT mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 253. doi:10.1158/1538-7445.AM2017-253
Abstract 2531: Regulation of androgen signaling axis and tumor suppressive function of miR-149-5p in prostate cancer
Authors: Singh Savita , Ebron Jey Sabith , Shankar Eswar , Gupta Sanjay , Lindner Daniel , Shukla Girish
Published: July 2017

Prostate cancer growth and proliferation depends on androgen signaling mediated by transactivation of Androgen Receptor (AR). Androgen ablation remains the mainstay therapy for treatment of the disease. However, despite androgen ablation, the disease relapses to more aggressive form known as castration-resistant prostate cancer (CRPC). Androgen Signaling Inhibitor such as Abiraterone Acetate and Enzalutamide are the most effective treatment methods currently being used to treat CRPC. However, more than one-third of CRPC patients develop resistance to these treatments, mostly due to the gain of function in the AR protein and increase in intratumoral dihydrotestosterone (DHT) synthesis. Intratumoral DHT synthesis from steroid precursors in tumors is augmented by up-regulation of enzymes of cholestrogenesis and steroidogenesis, such as HMG-CoA reductase, SCARB1, and 17βHSD respectively. Tumor-specific downregulation of microRNAs which regulate the AR and steroid biosynthesis has been implicated in tumor growth and resistance to therapeutics in CRPC. We are focusing on tumor suppressive role of miR-149-5p in PCa. We discovered that miR-149-5p expression was significantly lower in prostate cancer tissues compared to normal tissues. The mechanistic investigation revealed that miR-149-5p downregulates wild type and alternatively spliced variant of AR. It also down regulates the expression of SCARB1, HMGCS and HMG-CoA reductase, the proteins known to facilitate intratumoral DHT synthesis. Ectopic expression of miR-149-5p negatively regulated the expression of prostate-specific antigen, a downstream target of androgen signaling and it also inhibited invasion and proliferation of CRPC cells. Our findings indicate a significant role of miR-149-5p in regulating androgen signaling and possibly DHT synthesis in CRPC. This provides a strong rationale for further investigating the significance of miR-149-5p for generation of new therapeutic for CRPC.

Citation Format: Savita Singh, Jey Sabith Ebron, Eswar Shankar, Sanjay Gupta, Daniel Lindner, Girish Shukla. Regulation of androgen signaling axis and tumor suppressive function of miR-149-5p in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2531. doi:10.1158/1538-7445.AM2017-2531
Abstract 2533: Sox2 promotes cell proliferation of esophageal squamous cell carcinoma through the miR-17-92 cluster ,PTEN,AKT,mTORC1 pathway
Authors: Terasaki Kei
Published: July 2017

SOX2, a member of the SOX family of transcription factors, play an important role of differentiation and morphogenesis of the esophagus. We previously revealed that SOX2 is the target of gene amplification at 3q26 in esophageal squamous cell carcinoma (ESCC) (Cancer Genet Cytogenet. 2010), and that SOX2 promotes ESCC cell proliferation in vitro and in vivo through the activation of the AKT/mTORC1 signaling pathway (Cancer Sci. 2013). However, the mechanisms by which SOX2 promotes AKT/mTORC1 signaling remain unknown. It is known that PTEN is a negative regulator of AKT and the PTEN gene is a target of the miR-17-92 cluster. In the present study, we showed that SOX2 up-regulated the expression of miR-17-92 cluster and repressed PTEN expression using RNA interference (RNAi)-mediated knockdown of SOX2 and enforced expression of SOX2. In summary, SOX2 promotes cell proliferation of ESCC through the miR-17-92 cluster /PTEN/AKT/mTORC1 pathway.

Citation Format: Kei Terasaki. Sox2 promotes cell proliferation of esophageal squamous cell carcinoma through the miR-17-92 cluster ,PTEN,AKT,mTORC1 pathway [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2533. doi:10.1158/1538-7445.AM2017-2533
Abstract 2534: miRNA expression as potential biomarker for synovial sarcoma
Authors: Pazzaglia Laura , Pollino Serena , Vitale Mattia , Conti Amalia , Picci Piero , Benassi Maria Serena
Published: July 2017

Synovial sarcoma (SS) is a rare tumor, with dismal survival when metastatic. SS contains a characteristic translocation (X;18)(p11;q11), representing the fusion of SYT on chromosome 18 with either SSX1, SSX2, or rarely SSX4 on chromosome X The resulting fusion genes appear to be mutually exclusive and concordant in primary and metastatic tumours. New prognostic and predictive factors are needed. Chemokine receptor 4 (CXCR4) is a seven-transmembrane G protein-coupled chemokine receptor and it is the chemokine receptor most commonly expressed in tumour cells, involved in cell migration and invasion, as well as angiogenesis. microRNAs (miRNAs) are involved in post-transcriptional gene expression regulation and control important physiological processes like development, cell differentiation and cell signaling. Altered expression of miRNAs is strongly correlated with the malignant phenotype and there is data reporting a strong association between microRNA expression, patient age and STS prognosis. By three different databases (miRBase, TargetScan , miRanda) and by literature data we identified two miRNA regulators of CXCR4, miR-133b and miR-494. The expression of these miRNAs was evaluated by RT-PCR in 42 SS primary samples stored at Rizzoli biobank. 20 tissues from non oncologic patients were used as control. Our results showed a significant lower expression of miR-133b and miR-494 (respectively p=0.0005 and p=0.001) when compared to non tumor tissue. In vitro study on SW982 cell line with miR-133b precursor show a CXCR4 downregulation and a decrease of cell proliferation. Our preliminary data confirmed a miR-133b and miR-494 downregulation in SS. Correlation with clinical data, with CXCR4 expression and in vitro studies also with miR-494 in several SS cell lines are on-going to better investigate their role as potential prognostic and therapeutic markers.

Citation Format: Laura Pazzaglia, Serena Pollino, Mattia Vitale, Amalia Conti, Piero Picci, Maria Serena Benassi. miRNA expression as potential biomarker for synovial sarcoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2534. doi:10.1158/1538-7445.AM2017-2534
Abstract 2536: miR-187-5p and miR-219a-1-3p: potential biomarkers associated with chemotherapeutic response and prognosis in ovarian cancer
Authors: Huang Chia-Yen , Huang Hsien-Da
Published: July 2017

Background: Epithelial ovarian cancer (EOC) is the fifth-most common cause of female cancer death and is associated with high recurrence and mortality despite recent advancements in therapeutic strategies. Chemoresistance remains the main cause of treatment failure in EOC patients. The aim of this study is to identify specific miRNA markers closely associated with the chemoresponse in EOC patients.

Methods: We analyzed 374 serous ovarian cancer patients who receiving combination chemotherapy from The Cancer Genome Atlas (TCGA) and identified the most significantly altered miRNAs between different groups patients of chemotherapy response. We then used Kaplan-Meier and log-rank methods to analyze the relationship between these miRNAs and progression-free and overall survival in TCGA (n = 460) and Bagnoli (n = 130) datasets. In vitro study for response to chemotherapy agents were performed in human ovarian cancer cell lines and their transfectants. The biological relevance of putative miRNA targets was also analyzed using bioinformatics.

Results: MiR-187-5p and miR-219a-1-3p were associated with better response to chemotherapy and longer progression-free and overall survival in two independent epithelial ovarian cancer patient cohorts (all p <0.05). These two miRNAs also sensitized ovarian cancer cells to chemotherapy, thus recapitulating the clinical observation.

Conclusions: This study showed that miR-187-5p and miR-219a-1-3p could be useful biomarker for prediction of chemotherapy response and survival in serous ovarian cancers. MiR-187-5p and miR-219a-1-3p may be potential molecules in the treatment of EOC for sensitizing cancer cells to chemotherapy.

Citation Format: Chia-Yen Huang, Hsien-Da Huang. miR-187-5p and miR-219a-1-3p: potential biomarkers associated with chemotherapeutic response and prognosis in ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2536. doi:10.1158/1538-7445.AM2017-2536
Abstract 2537: MicroRNA targeting anti-apoptotic and G2/M pathways as therapeutic targets for castration resistant prostate cancer
Authors: Tarapore Pheruza , To Sarah , Ouyang Bin , Leung Yuet-Kin , Cheong Ana , Ho Shuk-mei
Published: July 2017

Prostate cancer (PC) is one of the most common cancers in men. Unfortunately, limited treatment options currently exist for those who have developed advanced castration-resistant PC (CRPC). G-1 is a GPER1/GPR30 agonist, and a promising candidate for CRPC therapy. G-1 is effective in halting the growth of CR tumors but not those grown in intact hosts. These findings suggest GPER1 is a therapeutic target for CRPC. We found that G-1, through activation of GPER1, inhibited growth of CRPC cells via cell-cycle arrest at the G2-M phase, probably leading to mitotic catastrophy. However, the exact mode of action of G-1 was not known. To better understand the pathways involved in G-1 action, we conducted a genome-wide mRNA-seq and miRNA-seq study on G-1 treated xenografts. We identified a panel of novel G-1-associated tumor suppressive miRNAs and genes. Moreover, Ingenuity Pathway Analysis revealed that the G-1 differentially regulated genes are involved in “Cellular Growth and Proliferation”, “endocrine function” and “Cancer” pathways. We validated the expression of the key miRNA (miR-34c, miR-10b, miR-138 and miR218) and genes in G-1 treated castration resistant xenografts and cell lines (C4-2 and 22Rv1). Furthermore, we have shown the tumor suppressor function of these miRNA in cell survival, migration, and invasion. The predicted target genes were next examined for decreased expression by qRT-PCR. We confirmed decreased expression of some of the downstream targets, which consist of genes involved in cell cycle regulation (CCNA and CCND, CDK1, CDK4, PLK1), cell survival (Bcl2, Survivin), cell migration/F-actin formation (LASP, PCDH7, ITGA9, ROBO1, SLIT1) and G2/M checkpoint (CDK1, PLK1, BCL-2 Survivin). Thus these miRNAs - miR-34c, miR-10b, miR-138 and miR218 - are ideal candidates for therapy of CRPC.

Citation Format: Pheruza Tarapore, Sarah To, Bin Ouyang, Yuet-Kin Leung, Ana Cheong, Shuk-mei Ho. MicroRNA targeting anti-apoptotic and G2/M pathways as therapeutic targets for castration resistant prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2537. doi:10.1158/1538-7445.AM2017-2537
Abstract 254: The potential of Lactobacillus probiotic treatments in colorectal cancer (CRC)
Authors: Kahouli Imen , Malhotra Meenakshi , Westfall Susan , Alaoui-Jamali Moulay , Prakash Satya
Published: July 2017

Colorectal cancer (CRC) is the third leading cause of death worldwide. It is known to be a type of cancer that is preventable by changes in diet and lifestyle. Mounting evidence are supporting the role of gut microbiome in the etiology of CRC and emphasize on the potential of probiotics as biotherapeutics in the prevention and management of CRC. Lactobacillus probiotic bacteria were suggested to balance pathogenic and oncogenic microbial community in the colon and produce anti-tumorigenic and anti-inflammatory effects in healthy individuals at risk and CRC patients. There is a need, however, for studies that focus on identifying potent probiotic strains with activity against CRC and inhibit cancer growth. This report discusses and present findings about the formulation of novel probiotic Lactobacillus biotherapeutic for CRC based on anti-CRC proliferative effect, immune modulation and metabolic activity, in vitro and in vivo, using a genetically-induced animal CRC model. Results and metabolomic analysis demonstrated the potential acrion of probiotic treatment to change host and gut microbiome co-metabolic profiles, produce local and systemic anti-inflammatory effects, inhibit cancer-causing events, and improve overall gut health.

Note: This abstract was not presented at the meeting.

Citation Format: Imen Kahouli, Meenakshi Malhotra, Susan Westfall, Moulay Alaoui-Jamali, Satya Prakash. The potential of Lactobacillus probiotic treatments in colorectal cancer (CRC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 254. doi:10.1158/1538-7445.AM2017-254
Abstract 2558: MYC-dependent transformation model of triple-negative breast cancer in vivo
Authors: Lourenco Corey , Kalkat Manpreet , Dingar Dharmesh , Melo Jason De , Yu Rosemary , Penn Linda
Published: July 2017

Recent comprehensive breast cancer studies examining mutations and genomic alterations have determined that deregulation of MYC and the PI3K pathway occur frequently during breast cancer progression and may be useful targets for therapy. As a result, there have been large efforts to develop PI3K, AKT and mTOR inhibitors (PAM inhibitors) for clinical use, however clinical trial data demonstrates that many patients treated with PAM inhibitors develop resistant disease. An alternative strategy would be to target Myc, though a lack of effective and specific inhibitors makes this difficult. To identify the core vulnerabilities in these cancers we developed an in vivo xenograft model of triple-negative breast cancer driven by deregulated PI3K signaling and MYC. We hypothesize that determining how these pathways co-operate to transform normal human breast cells into breast carcinomas will reveal a tumor progression signature and highlight new therapeutic opportunities. We developed our model using the spontaneously immortalized, basal, triple-negative MCF10A cell line. By expressing the hotspot PIK3caH1047R protein alone in MCF10A cells (MCF10.H) in addition to MYC (MCF10.HM), we can model normal/early breast cancer and invasive ductal carcinoma respectively. This is the first in vivo human model of breast cancer dependent on MYC for transformation. When injected into female NOD-SCID mice, MCF10A.H cells form organized acinar ducts embedded in extracellular matrix. MCF10A.H ducts form with hollow lumen and a single layer of myoepithelial cells, recapitulating normal human breast histology. Alternatively, MCF10A.HM cells grow as high-grade carcinomas indicative of invasive disease. MCF10A.H benign growths and MCF10A.HM tumors remain basal-like and triple-negative by immunohistochemistry. Importantly, MCF10A.HM tumors are sensitive to MYC repression and therefore may be a suitable model to evaluate direct and indirect anti-MYC therapies. Having relevant human xenograft samples representing both normal and IDC tissue, we performed RNA-seq to identify a MYC-signature driving breast cancer transformation. Our current work will involve targeting the resulting MYC-driven pathways identified by RNA-seq to therapeutically target MYC in breast cancer.

Citation Format: Corey Lourenco, Manpreet Kalkat, Dharmesh Dingar, Jason De Melo, Rosemary Yu, Linda Penn. MYC-dependent transformation model of triple-negative breast cancer in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2558. doi:10.1158/1538-7445.AM2017-2558
Abstract 2565: VCP/p97 segregase-mediated regulation of chromatin-bound PTEN stability
Authors: He Jinshan , Wani Gulzar , Zhu Qianzheng , Wani Altaf A
Published: July 2017

Phosphatase and Tensin homolog (PTEN) tumor suppressor protein is associated with many human cancers. PTEN has been shown to accumulate in the nucleus and control DNA repair in response to genotoxic stress. PTEN down-regulation impairs the capacity of global genomic nucleotide excision repair by suppressing the early DNA damage sensor, Xeroderma pigmentosum C (XPC), protein. Our recent work has demonstrated that the Valosin-containing protein (VCP)/p97 segregase participates in proteolytic processing of XPC and Cockayne syndrome B (CSB) proteins. Here, we show that (i) VCP/p97 segregase, in conjunction with its adaptor proteins, specifically extracts PTEN from damaged chromatin for targeted proteasomal degradation, (ii) inhibition of VCP/p97 activity induces the accumulation of PTEN on chromatin, and (iii) VCP/p97 physically interacts with PTEN. Depletion of VCP/p97, in p97-knockout cells or siRNA-mediated ablation in normal cells, affects the stability of PTEN in response to cellular UV irradiation. Results show that compromising the proteasome and VCP/p97 functions causes the accumulation of PTEN accompanied by an increase of UBXD7, proteasomal RPN2 and Sug1 within the chromatin compartment. To our knowledge, this is the first report to reveal that VCP/p97 segregase extracts tumor suppressor PTEN from damaged chromatin. (This work was supported by NIH grants ES002388 and ES012991 to AAW).

Citation Format: Jinshan He, Gulzar Wani, Qianzheng Zhu, Altaf A Wani. VCP/p97 segregase-mediated regulation of chromatin-bound PTEN stability [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2565. doi:10.1158/1538-7445.AM2017-2565
Abstract 2568: Mutant p53 regulates HSP70 expression and nuclear localization
Authors: Polireddy Kishore , Singh Kanchan , Pruski Melissa , Dar Wasim , Bynon John S. , Bailey Jennifer M.
Published: July 2017

Pancreatic cancer is the 3rd leading cause of cancer related deaths in the US with a median survival of less than one year. No effective therapies or early detection tests are available for these patients. Scientists have been studying cellular origins of pancreatic cancer to aid in the development of novel treatments and biomarkers. Several studies have demonstrated that acinar cells have a high propensity to undergo acinar to ductal metaplasia and form precursor lesions of pancreatic ductal adenocarcinoma. We have recently shown that simultaneous expression of Kras and mutant TP53 can generate invasive ductal adenocarcinoma from ductal cells. We hypothesized specific mutations in TP53 have different mechanisms of transforming ductal cells. In order to understand the role of mutant TP53 in transforming pancreatic ductal cells into invasive ductal adenocarcinoma, we used a lentiviral system to express mutant TP53R175H and TP53R273H, two of the most frequently mutated TP53 alleles in pancreatic cancer patients, in immortalized pancreatic ductal epithelial cells carrying a Kras mutation (HPNE-KrasG12D). Trypan blue dye exclusion assay and Spheroid formation assays were used to study cellular proliferation and cancer stem cell (CSC) populations. Mutant TP53 over expression enhanced CSC populations without altering cellular proliferation in HPNE-KrasG12D cells. Reverse phase protein array (RPPA) was carried out to detect gene expression changes in HPNE-KrasG12D cells upon mutant TP53 over expression. RPPA assay results suggested that TP53R175H uniquely induced HSP70 expression in HPNE-KrasG12D cells, as cells expressing either vector control or TP53R273H failed to do so. HSP70 expression was further validated by transiently overexpressing TP53R175H and TP53R273H. Surprisingly, TP53R175H specifically promoted nuclear localization of HSP70 without altering the expression of a recently identified HSP70 nuclear transporter, Hikeshi. Future studies will determine 1) whether HSP70 is required for p53-mediated stemness in HPNE-KrasG12D cells and 2) the function of nuclear HSP70. In summary, over expression of mutant p53 enhanced cancer stem cell properties of HPNE-KrasG12D cells, through upregulation HSP70. The exact mechanism behind HSP70 nuclear localization and increased cancer stem cell properties is being more rigorously explored.

Citation Format: Kishore Polireddy, Kanchan Singh, Melissa Pruski, Wasim Dar, John S. Bynon, Jennifer M. Bailey. Mutant p53 regulates HSP70 expression and nuclear localization [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2568. doi:10.1158/1538-7445.AM2017-2568