bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 1403: HOTAIR functions through NF-κB pathway in regulating ovarian cancer stem cells
Authors: Wang Weini , Fang Fang , Özeş Ali R. , Nephew Kenneth P. 
Published: September 2020

Abstract
Ovarian cancer (OC) is the fifth leading cause of cancer-related death among American women. Persistence of OC stem cells (OCSCs) is believed to contribute to resistance to platinum-based chemotherapy and disease relapse. Long non-coding RNA HOXC transcript antisense RNA (HOTAIR) has been shown to be associated with chemoresistance and overexpressed in many types of cancers, including high-grade serous OC (HGSOC). Previously published work has demonstrated that NF-κB was activated by HOTAIR through I-κB inhibition via trimethylation of histone H3 lysine K27, which contributes to chemoresistance in HGSOC. NF-κB-medicated signaling pathways involved in maintaining characteristics of CSCs, such as targeting stem cell markers, CD44, CD133, and ALDH1 has been demonstrated but not well defined in OC. The goals of this study are to understand the mechanism of HOTAIR-mediated NF-κB signaling pathway in regulating OCSCs and develop novel strategies to target OCSCs and overcome OC recurrence and drug resistance. Quantitative RT-PCR analysis revealed that HOTAIR was overexpressed in OCSCs compared to non-OCSCs. In order to produce loss-of-function phenotypes of HOTAIR and investigate the function of this gene, we utilized the paired CRISPR guide RNA design to delete the functional sites of HOTAIR without affecting nearby protein-coding gene. Knockout of HOTAIR re-sensitized OC cells to platinum treatment and significantly decreased (P&lt;0.001) OCSC population and stemness-related phenotypes, including spheroid formation and colony formation ability. ALDH1A1 and expression of other stemness-related genes, including Notch3, PROM1 were significantly decreased by HOTAIR knockout. Overexpression of HOTAIR in OC cells significantly increased (P&lt;0.05) these stem-like characteristics. Furthermore, we showed NF-κB nuclear accumulation and activation in OCSCs compared to non-OCSCs. Knockout of HOTAIR decreased (P&lt;0.01) nuclear localization of NF-κB in OCSCs. Inhibiting NF-κB in using a commercially available pharmacological approach as well as NF-κB knockout both significantly decreased OCSC population and stemness-related phenotypes, as well as ALDH1 protein expression (P&lt; 0.01). However, inhibition of NF-κB has no effect on OCSC characteristics in HOTAIR knockout cells, indicating that HOTAIR may function through constitutively activated NF-κB in regulating OCSCs. We suggest a better understanding of HOTAIR- NF-κB axis in regulating OCSCs will facilitate identifying the key therapeutic target to eliminate residual tumor cells after conventional chemotherapy and prevent OC recurrence and drug resistance.
Citation Format: Weini Wang, Fang Fang, Ali R. Özeş, Kenneth P. Nephew. HOTAIR functions through NF-κB pathway in regulating ovarian cancer stem cells [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1403.
Abstract 141: G9a regulates tumorigenicity and stemness through genome-wide DNA methylation reprogramming in non-small cell lung cancer
Authors: Pangeni Rajendra P. , Yang Lu , Zhang Keqiang , Wang Jinhui , Li Wendong , Guo Chao , Yun Xinwei , Sun Ting , Wang Jami , Raz Dan J. 
Published: September 2020

Abstract
Eukaryotic Histone Methyltransferase 2 (EHMT2 or G9A) has been regarded as a potential target for Non-Small Cell Lung Cancer (NSCLC) therapy. To investigate the regulatory roles of G9A in tumorigenesis, and stemness, we isolated and enriched tumor-initiating cells (TIC) from surgically resected NSCLC tissues by FACS and sphere formation assays. We then knocked down G9A using shRNA and carried out genome-wide 850K methylation array and RNA sequence analyses. We identified 67 genes hypomethylated and 143 genes upregulated following G9A knockdown of which 43 genes were both hypomethylated and upregulated. We selected 6 genes (CDYL2, DPP4, SP5, FOXP1, STAMBPL1 and ROBO1) for validation. These genes are involved in epigenetic regulation in human cancers, signaling pathways, other biological processes and have roles in patients' prognosis. In addition, G9A expression was higher in TICs and targeting G9a by shRNA knockdown or by selective inhibitor UNC0638 significantly inhibited the expression of cancer stem cell markers and sphere forming capacity, in vitro proliferation and in vivo growth. Further, transient overexpression of FOXP1 in TICs resulted in downregulation of stem cell markers and sphere forming capacity and cell proliferation in vitro indicating that the genes we identified are directly regulated by G9A through aberrant DNA methylation and subsequent expression. These data suggest that G9A contributes to epigenetic regulation by maintaining DNA methylation of multiple genes genome-wide and their expression.
Citation Format: Rajendra P. Pangeni, Lu Yang, Keqiang Zhang, Jinhui Wang, Wendong Li, Chao Guo, Xinwei Yun, Ting Sun, Jami Wang, Dan J. Raz. G9a regulates tumorigenicity and stemness through genome-wide DNA methylation reprogramming in non-small cell lung cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 141.
Abstract 1411: Population level genetic differentiation at the PVT1 gene locus: Implications for prostate cancer
Authors: Pal Gargi , Di Lia , Orunmuyi Akintunde , Olapade-Olaopa E. Oluwabunmi , Qiu Weigang , Ogunwobi Olorunseun O. 
Published: September 2020

Abstract
The incidence and mortality rate of prostate cancer (PCa) is highest in males of African ancestry. PCa is a multi-factorial, complex disease, but the exact mechanisms for its development and progression are unclear. Analysis of data from the one thousand genomes project revealed that a 26-kb region spanning PVT1 exons 4A and 4B shows a run of 75 SNPs with distinct allelic frequencies between African and non-African populations. The gene desert located on chromosome 8q24 is associated with aggressiveness of PCa in males of African ancestry. Interestingly, the non-protein coding gene locus Plasmacytoma Variant Translocation (PVT1) present at 8q24 is overexpressed in PCa. PVT1 gives rise to multiple transcripts with potentially different functions. To investigate if our observed population-level differences at the PVT1 gene locus have implications for PCa, we determined the expression of PVT1 exons 4A and 4B in histologically confirmed normal prostate (n=22), benign tumor prostate (n=35), and malignant tumor prostate tissue (n=28) samples obtained from males who had undergone prostatectomy or transrectal ultrasound-guided biopsy in Nigeria, a sub-Saharan Black African population. We have observed that PVT1 exons 4A and 4B are significantly overexpressed in PCa tissues in comparison to others. Transient and stable overexpression of PVT1 exons 4A and 4B significantly induce greater prostate epithelial cell migration and proliferation. We anticipate that further exploration of the role of PVT1 exons 4A and 4B may lead to the possibility of exploiting them for diagnosis, therapy, and other clinical applications in PCa.
Citation Format: Gargi Pal, Lia Di, Akintunde Orunmuyi, E. Oluwabunmi Olapade-Olaopa, Weigang Qiu, Olorunseun O. Ogunwobi. Population level genetic differentiation at the PVT1 gene locus: Implications for prostate cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1411.
Abstract 1426: A PI3K/AKT scaffolding protein, IQ motif-containing GTPase associating protein 1 (IQGAP1), promotes head and neck carcinogenesis
Authors: Wei Tao , Choi Suyong , Buehler Darya , Anderson Richard A. , Lambert Paul F. 
Published: September 2020

Abstract
Purpose: Head and neck cancer (HNC) is the sixth most common cancer worldwide with a 5-year survival rate of less than 50%. The PI3K/AKT/mTOR signaling pathway is frequently implicated in HNC. Recently, IQ motif-containing GTPase activating protein 1 (IQGAP1) was discovered to scaffold the PI3K/AKT signaling pathway. IQGAP1 gene expression is increased in HNC, raising the hypothesis that IQGAP1 contributes to HNC.
Experimental Design: We performed a combination of in vitro studies using human cancer cell lines treated with a cell permeable peptide that interferes with IQGAP1's ability to bind to PI3K, and in vivo studies utilizing mice genetically knocked out for the Iqgap1 (Iqgap1-/-). In vivo EGF-stimulation assays were used to evaluate PI3K signaling. To study the role of IQGAP1 in HNC, we used a well-validated mouse model that drives HNC via a synthetic oral carcinogen, 4-nitroquinoline 1-oxide (4NQO).
Results: IQGAP1 is necessary for efficient PI3K signaling in vitro and in vivo. Disruption of IQGAP1-scaffolded PI3K/AKT signaling reduced HNC cell survival. Iqgap1-/- mice had significantly lower cancer incidences, lesser disease severity and fewer cancer foci. IQGAP1 protein levels were increased in HNC arising in Iqgap1+/+ mice. The level of PI3K signaling in 4NQO-induced HNC arising in Iqgap1-/- mice was significantly reduced, consistent with the hypothesis that IQGAP1 contributes to HNC at least partly through PI3K signaling. High IQGAP1 expression correlated with reduced survival, and high pS6 levels correlated with high IQGAP1 levels in HNC patients.
Conclusions: These data demonstrate that IQGAP1 contributes to head and neck carcinogenesis.
Citation Format: Tao Wei, Suyong Choi, Darya Buehler, Richard A. Anderson, Paul F. Lambert. A PI3K/AKT scaffolding protein, IQ motif-containing GTPase associating protein 1 (IQGAP1), promotes head and neck carcinogenesis [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1426.
Abstract 1432: TORC2 dependent control of cell growth and size in cancer cells
Authors: DeWitt Jerry T. , Kellogg Douglas 
Published: September 2020

Abstract
Severe defects in cell growth and size are a nearly universal feature of cancer cells and have provided a basis for cancer pathology for over 100 years; however, the underlying mechanisms remain largely unknown. Recent work in budding yeast has shown that a highly conserved signaling network surrounding Tor complex 2 (TORC2) controls cell growth and size. A key component of the network is the yeast homolog of serum and glucocorticoid-regulated kinase (SGK), which controls production of ceramide signaling lipids that control cell growth and size. Here, we present evidence that a similar TORC2 network controls cell growth and size in mammalian cells. In addition, we show that expression of oncogenic drivers in NIH3T3 cells causes defects in cell size, as well as defects in TORC2-dependent control of cell size. Cancer cells also show severe defects in TORC2-dependent control of cell size. Our working hypothesis is that the TORC2 network is downstream of multiple oncogenes, and that aberrant TORC2 signaling is a major cause of the nearly universal size defects observed in cancer cells. A better understanding of the mechanisms that control cell growth and size in normal cells, and how they go awry in cancer, could identify new targets for drugs to improve cancer therapies.
Citation Format: Jerry T. DeWitt, Douglas Kellogg. TORC2 dependent control of cell growth and size in cancer cells [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1432.
Abstract 1439: NUDT5 is a critical regulator of triple-negative breast cancer growth
Authors: Qian Jing , Tahaney William , Ma Yanxia , Bollu Lakshmi , Mazumdar Abhijit , Hill Jamal , Zhang Yun , Brown Powel 
Published: September 2020

Abstract
Background: Triple-negative breast cancers (TNBC) represent 15% of all breast cancers, and are highly aggressive cancers with poor clinical outcome. We have previously conducted a whole phosphatase RNA microarray analysis of TNBCs compared to estrogen receptor (ER)-positive breast cancers. These studies identified phosphatases that were either over-expressed or under-expressed in TNBCs as compared to ER-positive breast cancers. One of the phosphatases highly expressed in TNBCs was NUDT5, which hydrolyzes 8-oxo-dGDP and ADP-ribose (ADPR). Recent studies have shown that NUDT5 regulates cell cycle progression, and increases cellular ATP in response to hormone stimulation in cancer cells. However, the biological function of NUDT5 in TNBCs is largely unknown.
Hypothesis: We hypothesized that NUDT5 is a critical phosphatase over-expressed in TNBCs that regulates the growth of these breast cancer cells.
Methods: We analyzed TNBC NUDT5 mRNA expression and clinical outcome using publicly available TCGA, METABRIC, and the CCLE datasets. Overall survival was evaluated using Kaplan-Meier curves and compared using log-rank analysis (* p&lt;0.05). We next conducted siRNA knockdown studies using DharmaFECT transfection, and subsequently measured the effect on growth using automated cell counting. Results at day 7 were expressed as mean cell numbers +/- standard deviation, and analyzed using Student's t-tests.
Results: Analysis of NUDT5 mRNA expression demonstrated that NUDT5 is overexpressed in triple-negative breast cancers, specifically in the basal-like subtype of TNBC. Analysis of publically available breast cancer datasets showed that high NUDT5 expression is associated with poor overall survival of breast cancer patients. Knockdown of NUDT5 decreased TNBC growth, but did not decrease the growth of non-TNBC cells.
Conclusions: Our results demonstrate that NUDT5 is a critical regulator of TNBC growth, and raise the possibility of targeting this critical phosphatase for the treatment of TNBC tumors. Future studies will investigate the function of NUDT5 in regulating nucleotide pool metabolism in TNBCs. Understanding the role of NUDT5 in controlling TNBC growth will provide the basic science foundation for the future development of NUDT5 inhibitors for the treatment of women with these aggressive, potentially life-threatening cancers. This work was supported by Susan G Komen Promise Grant (PB), and the John Charles Cain Endowment (PB).
Citation Format: Jing Qian, William Tahaney, Yanxia Ma, Lakshmi Bollu, Abhijit Mazumdar, Jamal Hill, Yun Zhang, Powel Brown. NUDT5 is a critical regulator of triple-negative breast cancer growth [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1439.
Abstract 1478: Endothelial-specific loss of glutaminase normalizes tumor blood vessels and inhibits tumor growth
Authors: Ngwa Verra , Edwards Deanna , Chen Jin 
Published: September 2020

Abstract
Abnormal tumor blood vessels with chaotic angiogenic sprouting result in spontaneous hemorrhages and increased interstitial fluid pressure in the tumor microenvironment. These defects of intra-tumoral vessels lead to poor leukocyte trafficking and drug delivery. Although there is a solid published premise for tumor blood vessel normalization, mechanisms of improved tumor vessel quality are only beginning to be investigated. Because tumor vascular endothelial cells are fast growing, they require nutrients to generate biomass that support their proliferative program. Indeed, inhibition of glucose metabolism has been shown to normalize tumor vasculature and improve drug delivery. In addition to glucose, glutamine is also essential for endothelial cell proliferation and angiogenic sprouting. Thus, we hypothesized that tumor associated endothelium may require glutamine metabolism to support their rapid proliferation and blocking glutaminolysis would normalize tumor vasculature. To test this hypothesis, we crossed glutaminase (GLS) floxed (GLS f/f) animals with CDH5 (VE-Cad)-CreER transgenic mice to induce endothelial-specific deletion of GLS upon tamoxifen administration (GLSECKO). We found that there is a decrease in tumor growth in GLSECKO animals compared to WT recipients. Loss of GLS in endothelium leads to a decrease in CD31+ angiogenic sprouts, and a better coverage of SMA+ pericytes in capillaries. We also observed an increase in tomato-lectin perfused blood vessels and a decrease in tissue hypoxia, as judged by pimonidazole stain. Together, these results suggest that endothelial-specific loss of glutaminase normalizes tumor blood vessels. We are currently investigating the effects of endothelial-specific deletion of GLS on endothelial cell metabolism, tumor metastasis, lymphocytes infiltration, and the response to chemotherapy.
Success of this project will uncover the role of endothelial glutaminase in tumor vessels. Further, chemotherapies are currently the main treatment for TNBC patients, so improvements in drug delivery will have significant clinical impact. Finally, TNBCs lacking tumor infiltrating lymphocytes (TILS) are poorly responsive to immune checkpoint inhibitors (ICIs). Investigating ways to normalize tumor blood vessels will lay foundation for developing novel therapeutics to increase TILs in immunologically cold TNBCs to increase their response to ICIs.
Citation Format: Verra Ngwa, Deanna Edwards, Jin Chen. Endothelial-specific loss of glutaminase normalizes tumor blood vessels and inhibits tumor growth [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1478.
Abstract 1482: PIM1 promotes angiogenesis via phosphorylation and stabilization of HIF-1α
Authors: Casillas Andrea L. , Chauhan Shailender S. , Toth Rachel K. , Jensen Corbin C. , Warfel Noel A. 
Published: September 2020

Abstract
An essential process for the growth and dissemination of solid tumors is angiogenesis, or the formation of new blood vessels. Overexpression of Proviral Integration site for Moloney murine leukemia virus (PIM)-1, a serine-threonine kinase, has been implicated as a driver of aggressive prostate and colon cancer. PIM1 is known to promote tumor growth and survival, and we recently uncovered a role for PIM1 in promoting resistance to anti-angiogenic agents. Here, we identify a novel signaling pathway that directly links PIM to tumor angiogenesis. Immunohistochemical staining of prostate cancer tissue revealed a significant positive correlation between PIM1 and CD31 expression, a marker of endothelial cells. Using prostate cancer as a model, in vitro models of endothelial tube formation and DCE-MRI confirmed that PIM1 overexpression increases tumor angiogenesis. Gene expression analysis of PIM1 overexpressing cells showed that PIM kinases regulates the expression levels of many hypoxia inducible factor-1α (HIF-1α) target genes in normoxic conditions. In vitro, in vivo and kinase assays discovered a novel phosphorylation site within the oxygen-dependent degradation domain (ODDD) of HIF-1α that is a direct target of PIM1. Biochemical analysis demonstrates that phosphorylation of this site increases HIF-1α stability by decreasing PHD binding, hydroxylation, and subsequent proteasomal degradation of HIF-1α. Two CRISPR-generated cell lines with point mutations that mimic phosphorylation of this site were used in xenograft models of colon cancer to confirm the significance of this site to the identified PIM-HIF signaling and tumor angiogenesis. Importantly, we show that the anti-angiogenic and cytotoxic effects of PIM inhibitors are largely dependent on their ability to downregulate HIF-1α signaling. In summary, we uncovered a novel role for PIM1 in promoting tumor angiogenesis and identified a novel phosphorylation site that controls the stability of HIF-1α in normoxic and hypoxic conditions.This research yields important insight into the role of PIM signaling in solid tumors and provides preclinical evidence that to improve the translation of PIM kinase inhibitors in solid tumors.
Citation Format: Andrea L. Casillas, Shailender S. Chauhan, Rachel K. Toth, Corbin C. Jensen, Noel A. Warfel. PIM1 promotes angiogenesis via phosphorylation and stabilization of HIF-1α [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1482.
Abstract 149: Non-small cell lung cancer (NSCLC) detection by DNA methylation profiling and computational deconvolution
Authors: Hornstein Nicholas J. , Noor Zorawar S. , Pellegrini Matteo , Garon Edward 
Published: September 2020

Abstract
Purpose: Early detection of pulmonary malignancies is critical to achieving positive treatment outcomes. However, due to the minimal symptom burden often associated with early-stage neoplasms, in addition to the cost and limitations of advanced imaging modalities, detection of disease is often delayed until nodal or metastatic spread has occurred. Ongoing cellular turnover releases DNA into systemic circulation where it is able to achieve a steady state level. We postulated that we could identify methylation sites specific to pulmonary Squamous Cell Carcinoma (SCC) and Adenocarcinoma (AD) and then computationally determine the presence or absence of neoplastic signatures from a heterogeneous tissue sample, such as is found in cell free DNA isolated from plasma.
Methods: We designed a computational framework for the detection of informative methylation sites based on an iterative Euclidean Distance algorithm. After generation of a reference matrix comprised of 25 cells of origin, SCC and AD (via 444 biopsy-derived methylomes), we sought informative methylation sites which had unique expression patterns among the tested cell types. To quantify the reliability of this approach, we generated synthetic In sillico “plasma” samples comprised of varying compositions of SCC, AD and whole blood methylation data which we then deconvolved using a NNLS algorithm.
Results: We identified 200 informative sites out of 390,000 tested. Based on the 200 identified informative sites, we were able to define a Euclidean Space with robust separation of individual cell types (L2&gt;5). Pairings of CD4+/CD8+ T-Cells and SCC/AD had the closest Euclidean distances, likely related to cellular origin and biologic similarities. However, we accurately distinguished between these cell type pairs in &gt;95% of In silico experiments. Additionally, we demonstrated accurate detection of neoplastic signature within synthetic heterogeneous mixtures ranging from .1 to 100% of neoplastic “spike-in” (PearsonR =.92, p=1.5e-42). Going forward, we hope to further define the operating characteristics of this approach In vivo and develop its capability as we look to recapitulate our results with plasma samples from patients with and without pulmonary malignancies.
Conclusion: Here, we describe a computational framework for the detection of pulmonary malignancy via methylation signatures. Using this framework we identified 200 informative methylation sites which allow for In silico deconvolution and detection of NSCLC within heterogeneously complex samples.
Citation Format: Nicholas J. Hornstein, Zorawar S. Noor, Matteo Pellegrini, Edward Garon. Non-small cell lung cancer (NSCLC) detection by DNA methylation profiling and computational deconvolution [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 149.