bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 2736: Regulation of cytokinesis by polo-like kinase 4
Authors: Press Michael F. , Xie Bin , Davenport Simon , Zhou Yu , O’Brien Neil , Palazzolo Michael , Mak Tak , Brugge Joan , Slamon Dennis J. 
Published: July 2016

Abstract
Introduction. The serine/threonine mitotic kinase, polo-like kinase 4 (PLK4), is known to play a critical role in centrosome duplication in preparation for cell division. Based on our preliminary observations with a PLK4 kinase inhibitor, we investigated the possibility that PLK4 may also play a role in regulation of cytokinesis.
Experimental Procedures. Immunofluorescence was used to localize PLK4 and phospho-PLK4 in cultured human breast, ovarian, and colorectal cancer cell lines throughout the cell cycle without and with CFI-400945 PLK4 inhibitor and MG-115 protease inhibitor. Flow cytometry and videomicroscopy were used to analyze the consequences of PLK4 inhibition on cytokinesis.
Results. Using immunofluorescence, PLK4 was localized to centrosomes; however, we also found that phospho-PLK4 was cleaved and distributed to kinetochores (metaphase and anaphase), cleavage furrow (telophase), and middle body (cytokinesis) during cell division in colorectal, ovarian, and breast cancer cells. Distribution of phospho-PLK4 to the cleavage furrow and middle body raised the possibility that this kinase plays a functional role in cytokinesis. Using either CFI-400945 PLK4 kinase inhibitor or the MG-115 protease inhibitor, we found that PLK4 accumulated in centrosomes with inhibition of translocation of PLK4 to the middle body. This change in subcellular distribution of PLK4 was associated with generation of large, multi-nucleated tumor cells or tumor cells with polyploidy. Videomicroscopy confirmed that treatment with CFI-400945 PLK4 inhibitor was associated with prevention of cellular abscission in treated cells.
Conclusions. These observations demonstrate a role for phospho-PLK4 in facilitation of cytokinesis. A regulatory role for PLK4 in cytokinesis makes it a potential target for therapeutic intervention in appropriately selected cancers.
Citation Format: Michael F. Press, Bin Xie, Simon Davenport, Yu Zhou, Neil O’Brien, Michael Palazzolo, Tak Mak, Joan Brugge, Dennis J. Slamon. Regulation of cytokinesis by polo-like kinase 4. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2736.
Abstract 2740: Mechanistic basis of Palbociclib combinatorial activity in ER+ breast cancer and non-breast indications
Authors: Dann Stephen , Yuan Jing , Chionis John , Liu Chaoting , Xie Tao , Lee Nathan V. , Chen Enhong , Wei Ping , Rejto Paul A. , Shields David J. , VanArsdale Todd 
Published: July 2016

Abstract
Phosphorylation of the retinoblastoma protein (Rb) by cyclin-dependent kinases 4 and 6 (CDK4/6) is a critical checkpoint for G1/S cell cycle progression and commitment to cellular proliferation. Human malignancies often subvert these control mechanisms through a range of genetic and biochemical adaptations. Accordingly, tumors that depend on CDK4/6 activity for proliferation and survival are particularly sensitive to inhibition of this pathway by palbociclib (IbranceTM), a highly selective inhibitor of CDK4/6 kinase activities. Treatment regimen of palbociclib with letrozole significantly improved progression-free survival in a randomized phase 2 study of women with advanced estrogen receptor-positive (ER+), HER2-negative breast cancer. Likewise, in ER+ breast cancer models palbociclib and estrogen antagonists combine for greater anti-proliferative activity, increased hallmarks of cellular senescence and prolonged durability of response following drug removal. Dual inhibition of CDK4/6 and ER signaling demonstrated robust anti-tumor activity in xenograft studies. The addition of Palbociclib to other targeted therapeutics elicits improved activity in pre-clinical models of several non-breast indications and these effects also manifest through modulation of cellular proliferation, senescence and growth arrest. Data will be presented on the molecular basis of combination benefit with Palbociclib in ER+ breast and other oncology indications.
Citation Format: Stephen Dann, Jing Yuan, John Chionis, Chaoting Liu, Tao Xie, Nathan V. Lee, Enhong Chen, Ping Wei, Paul A. Rejto, David J. Shields, Todd VanArsdale. Mechanistic basis of Palbociclib combinatorial activity in ER+ breast cancer and non-breast indications. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2740.
Abstract 2741: A novel branched DNA-based multiplex method for telomere analysis at the single-cell level by flow cytometry
Authors: Lai Steve , Sias Leslie , Funatake Castle 
Published: July 2016

Abstract
Telomeres are protective structures at the ends of chromosomes, containing multiple repeats of the repetitive sequence (TTAGGG) in vertebrates. It undergoes progressive shortening during normal aging. Abnormalities in the regulation of telomere length are implicated in various diseases including cancers. Current methods for telomere analysis are tedious and lack the flexibility to allow identification of unique cell subsets in a heterogeneous sample. Here we describe a novel flow cytometric method for analyzing relative telomere length at the single-cell level based on the branched DNA technology. This method, named PrimeFlow Assay can be combined with antibody staining and mRNA detection enabling simultaneous analysis of telomere length as well as protein and RNA for a comprehensive view in any specific cell subset. With this method, we investigated various cell lines and primary cells of human and mouse origin. Our results indicate that transformed cell lines possess longer telomeres than primary cells. In human peripheral blood mononuclear cells, we observed that lymphocytes had longer telomeres compared to monocytes, consistent with previously published results by another flow cytometric method. These data demonstrate that the PrimeFlow assay is a valuable method for high-throughput analysis of relative telomere length that may be combined with the analysis of protein and gene targets and, thus, provides data at the single-cell level for a more complete understanding of sample heterogeneity.
Citation Format: Steve Lai, Leslie Sias, Castle Funatake. A novel branched DNA-based multiplex method for telomere analysis at the single-cell level by flow cytometry. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2741.
Abstract 2748: Targeting DNA repair deficient cancers with the cell-penetrating autoantibody 3E10
Authors: Turchick Audrey L. , Glazer Peter M. 
Published: July 2016

Abstract
There is growing evidence that many solid tumors have defective DNA repair pathways and cell cycle checkpoints. This has spurred development of therapeutics to specifically target cancer cells with defective DNA repair, but few have been successful outright due to problems such as general toxicity. One novel anti-cancer agent of interest to us is 3E10, a unique cell-penetrating, anti-DNA autoantibody. This molecule is non-toxic to normal cells on its own but has deleterious effects on cells with DNA repair deficiencies. Specifically, 3E10 has been shown to be synthetically lethal in BRCA2-deficient human cancer cells, to be synergistic with radiation and other commonly used DNA damaging therapies, and to reduce the efficiency of Rad51 mediated strand exchange and thus homologous recombination (HR). The goal of this project is to better understand how 3E10 can be used as a new paradigm for cancer treatment. New evidence suggests that 3E10 inhibits Exo1 exonuclease activity. Additionally, preliminary data shows that 3E10 physically interacts with Rad51, ultimately inhibiting Rad51 nuclear localization and foci formation. Additionally, a point mutation in 3E10 that confers increased DNA binding mediates increased cell death in BRCA2-deficient human cancer cells. Furthermore, studies investigating the potential therapeutic effect of 3E10 in patient derived primary melanoma cell lines show that 3E10 is synthetically lethal with PTEN deficiency. This data suggests that 3E10 inhibits HR by binding to DNA at double strand breaks and occupying sites normally processed by core repair machinery, as well as by physically interacting with Rad51. Overall, 3E10 holds great promise as a novel therapeutic agent for various cancers, including PTEN deficient melanomas.
Reference:
Hansen, J. et al. Targeting cancer with a lupus autoantibody. Science Translational Medicine 4, (2012)
Citation Format: Audrey L. Turchick, Peter M. Glazer. Targeting DNA repair deficient cancers with the cell-penetrating autoantibody 3E10. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2748.
Abstract 2763: DNA methylation profiling unveils TGF-β hyperresponse in tumor associated fibroblasts from lung cancer patients
Authors: Vizoso Miguel , Puig Marta , Carmona F. Javier , Maqueda María , Gomez Antonio , Labernardie Anna , Gabasa Marta , Mendizuri Saioa , Ikemori Rafael , Trepat Xavier , Moran Sebastian , Vidal Enrique , Reguart Noemí , Perera Alexandre , Esteller Manel , Alcaraz Jordi 
Published: July 2016

Abstract
There is growing interest in defining the aberrant molecular differences between normal and tumor-associated fibroblasts (TAFs) that support tumor progression. For this purpose, we recently conducted a genome-wide DNA methylation profiling of TAFs and paired control fibroblasts (CFs) from non-small cell lung cancer (NSCLC) patients, and reported a widespread hypomethylation concomitantly with focal gain of DNA methylation; in addition, we found evidence that a fraction of lung TAFs are fibrocytes in origin. Of note, the aberrant epigenome of lung TAFs had a global impact in gene expression and a selective impact on the TGF-β pathway. To get insights on the functional implications of the latter impact, we analyzed the response of lung TAFs to exogenous TGF-β1 in terms of activation and contractility. We found a larger expression of a panel of activation markers including α-SMA and collagen-I in TAFs compared to control fibroblasts. Likewise, TGF-β1 elicited a larger contractility in TAFs than in CFs as assessed by traction force microscopy. These findings reveal that lung TAFs are hyperresponsive to TGF-β1, which may underlie the expansion and/or maintenance of the tumor-promoting desmoplastic stroma in lung cancer.
Citation Format: Miguel Vizoso, Marta Puig, F. Javier Carmona, María Maqueda, Antonio Gomez, Anna Labernardie, Marta Gabasa, Saioa Mendizuri, Rafael Ikemori, Xavier Trepat, Sebastian Moran, Enrique Vidal, Noemí Reguart, Alexandre Perera, Manel Esteller, Jordi Alcaraz. DNA methylation profiling unveils TGF-β hyperresponse in tumor associated fibroblasts from lung cancer patients. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2763.
Abstract 2776: The relationship between UHRF1 overexpression and LINE-1 hypomethylation in esophageal squamous cell carcinoma
Authors: Nakamura Kenichi , Baba Yoshifumi , Kosumi Keisuke , Harada Kazuto , Shigaki Hironobu , Miyake Keisuke , Kurashige Junji , Ishimoto Takatsugu , Iwatsuki Masaaki , Yoshida Naoya , Baba Hideo 
Published: July 2016

Abstract
Background: Global DNA hypomethylation contributes to oncogenesis through multiple mechanism. The level of long interspersed nucleotide element-1 (LINE-1) methylation is regarded as a surrogate marker of global DNA methylation, and is drawing interest as a good indicator for predicting cancer prognosis. However, the mechanism by which LINE-1 (global DNA) methylation is controlled in cancer cells remains to be fully explored. Ubiquitin-like with PHD and RING finger domain 1 (UHRF1) plays an essential role in DNA methylation. Previous studies have demonstrated that UHRF1 overexpression might be a mechanism of underlying DNA hypomethylation in hepatocellular carcinoma, and contribute to poor prognosis. Nonetheless, the epigenetic role of UHRF1 in esophageal squamous cell carcinoma (ESCC) remains unclear.
Methods: Using 16 frozen tissues (matched pairs of cancer and normal epithelium), and 160 curatively resected esophageal cancer specimens, we analyzed the relationship between UHRF1 expression, LINE-1 methylation levels and patient outcome. We measured UHRF1 expression by real-time PCR and immunohistochemistry, and LINE-1 methylation levels by bisulfite- pyrosequencing technology. In addition, to investigate the relationships between UHRF1 expression and LINE-1 methylation level (i.e., global DNA methylation level) using UHRF1 overexpression vector and siRNA for UHRF1 with ESCC tissues and ESCC cell lines.
Results: In ESCC tissues, UHRF1 expression were significantly associated with LINE-1 methylation levels, and UHRF1 overexpression correlated with poor prognosis in our cohort of 160 ESCC patients. Furthermore, UHRF1 vector-mediated overexpression caused LINE-1 (global DNA) hypomethylation, and conversely, UHRF1 knockdown using siRNA increased DNA methylation in ESCC cell lines.
Conclusion: These results may suggest that UHRF1 is an epigenetic key regulator of DNA methylation, moreover, can be applicable to attractive cancer therapies.
Citation Format: Kenichi Nakamura, Yoshifumi Baba, Keisuke Kosumi, Kazuto Harada, Hironobu Shigaki, Keisuke Miyake, Junji Kurashige, Takatsugu Ishimoto, Masaaki Iwatsuki, Naoya Yoshida, Hideo Baba. The relationship between UHRF1 overexpression and LINE-1 hypomethylation in esophageal squamous cell carcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2776.
Abstract 2782: The effect of LINE-1 methylation level on survival in pancreatic cancer
Authors: Yamamura Kensuke , Baba Yoshifumi , Zhou Lei , Zhang Xiaobo , Kosumi Keisuke , Taki Katunobu , Harada Kazuto , Ishimoto Takatsugu , Imai Katsunori , Hashimoto Daisuke , Chikamoto Akira , Beppu Toru , Xiaodong Tan , Baba Hideo 
Published: July 2016

Abstract
Background: Genome-wide DNA hypomethylation plays an important role in genomic instability and carcinogenesis. DNA methylation in the long interspersed nucleotide element-1 (LINE-1) is a good indicator of the global DNA methylation level. In previous studies, we demonstrated that LINE-1 hypomethylation was strongly associated with a poor prognosis in some types of cancers including esophageal cancer, gastric cancer, and hepatocellular carcinoma, supporting its potential role as a prognostic marker. However, the relationship between LINE-1 hypomethylation and clinical outcome in pancreatic cancer remains unclear.
Methods: LINE-1 methylation level in 126 samples resected pancreatic cancers was measured by pyrosequencing assay, and the prognostic value of LINE-1 methylation level in pancreatic cancer was examined.
Results: Pancreatic cancers showed significantly lower LINE-1 methylation levels compared to matched non tumorous parenchyma (P = 0.039; N = 36). Tumoral LINE-1 methylation range was 41.3-92.8 (N = 126; mean: 77.7; median: 78.5; standard deviation: 5.7). However, LINE-1 hypomethylation was not significantly associated with overall survival, cancer specific survival, disease-free survival [log-rank p = 0.30, p = 0.18 and p = 0.50, respectively].
Conclusion: The present result suggested that LINE-1 hypomethylation in pancreatic cancer is not associated with poor prognosis. In this study, our cohort was small, therefore further accumulation of data may be needed in order to confirm the effect of LINE-1 methylation level on survival in pancreatic cancer.
Citation Format: Kensuke Yamamura, Yoshifumi Baba, Lei Zhou, Xiaobo Zhang, Keisuke Kosumi, Katunobu Taki, Kazuto Harada, Takatsugu Ishimoto, Katsunori Imai, Daisuke Hashimoto, Akira Chikamoto, Toru Beppu, Tan Xiaodong, Hideo Baba. The effect of LINE-1 methylation level on survival in pancreatic cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2782.
Abstract 280: Synergistic in vitro activity of MOR209/ES414 in combination with enzalutamide
Authors: Sewell Toddy , Blake Michelle , Gross Jane A. , Endell Jan , Weirather Johannes , Blankenship John W. 
Published: July 2016

Abstract
Metastatic castration-resistant prostate cancer (mCRPC) presents a daunting therapeutic challenge for patients who eventually progress after androgen ablation therapy. Although newer AR antagonists show a survival benefit, these patients ultimately relapse. Thus, it is critical to identify new therapies that will work in combination with AR antagonists or in AR-antagonist resistant settings. MOR209/ES414 is a bispecific ADAPTIR™ (modular protein technology) molecule currently under investigation in a phase 1 clinical trial in mCRPC, including patients that have progressed on enzalutamide. In pre-clinical studies, MOR209/ES414 has previously been shown to redirect T cell cytotoxicity against cells expressing Prostate Specific Membrane Antigen (PSMA). Here, we aimed to determine whether enzalutamide affects PSMA expression on CRPC cells in vitro, and could alter the effectiveness of MOR209/ES414 at inducing T-cell mediated tumor cell death.
To address these questions, we utilized a CRPC cell line, 22Rv1, which has low expression of PSMA and is resistant to enzalutamide. Treatment of 22Rv1 cells with 10 μM enzalutamide for 3 weeks resulted in increased PSMA cell surface expression as measured by flow cytometry. 22Rv1 cells exposed to enzalutamide were also more sensitive to MOR209/ES414-mediated T-cell lysis, with a 25% increase in cytotoxicity over a 4 hour chromium release assay compared to 22Rv1 cells that were not exposed to enzalutamide. A concomitant decrease in EC50 for MOR209/ES414-mediated lysis from 0.8 pM to 0.5 pM was also observed in 22Rv1 cells exposed to enzalutamide.
MOR209/ES414 and enzalutamide were next tested in combination using a PSMA-positive, enzalutamide-sensitive cell line, LNCaP cultured with primary T cells over several days. Suboptimal doses of MOR209/ES414 and enzalutamide were added to the cultures, and surviving LnCaP cells were quantitated 4 days later. Enzalutamide did not interfere with the ability of MOR209/ES414 to target T cells to LNCaP cells, and Combination Index analysis showed the activity of MOR209/ES414 and enzalutamide to be synergistic in vitro. These studies provide a rationale for further examination of combining MOR209/ES414 with enzalutamide, even in enzalutamide-resistant settings.
Citation Format: Toddy Sewell, Michelle Blake, Jane A. Gross, Jan Endell, Johannes Weirather, John W. Blankenship. Synergistic in vitro activity of MOR209/ES414 in combination with enzalutamide. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 280.
Abstract 2845: PRMT5-PTEN molecular pathway regulates senescence and self-renewal of Glioblastoma stem-like cells
Authors: Banasavadi-Siddegowda Yeshavanth Kumar , Russell Luke , Zhang Jianying , Karkhanis Vrajesh A. , Imitola Jaime , Baiocchi Robert , Kaur Balveen 
Published: July 2016

Abstract
PURPOSE: Glioblastoma (GBM) represents the most common and aggressive histologic subtype among malignant astrocytoma and is associated with poor outcomes because of heterogeneous tumor cell population including mature non-stem like cell and immature stem-like cells within the tumor. Thus, it is critical to find new target-specific therapeutic modalities. Protein arginine methyltransferase enzyme 5 (PRMT5) regulates many cellular processes through its methylation activity and its overexpression in GBM is associated with more aggressive disease. Previously, we have shown that silencing of PRMT5 expression in differentiated GBM cell lines results in apoptosis and reduced tumor growth in mice. Here we report the critical role of PRMT5 in differentiated GBM non-stem-like cells (non-GSC) grown in serum and undifferentiated GBM stem-like cells (GSC) grown as neurospheres in vitro.
METHODS: GSC grown in stem-cell media and non-GSC grown in serum were transfected with specified siRNAs. At appropriate time, these cells were tested for in vitro proliferation, self-renewal capacity, apoptosis, cell cycle progression, mRNA expression and protein expression. Also, using intracranial mouse xenograft, tumor forming ability of PRMT5-intacta and depleted GSC and non-GSC was determined.
RESULTS: Our results uncover a very significant role for PRMT5 in GSC self-renewal capacity and proliferation. PRMT5 knockdown in non-GSC led to apoptosis, knockdown in GSC led to G1 cell cycle arrest through upregulation of p27 and hypophoshorylation of Rb protein, leading to senescence. Comparison of impact of PRMT5 on cellular signaling by Human Phospho-Kinase Array and ChIP-PCR revealed that unlike non-GSC, PRMT5 controls both AKT and ERK activity by direct repression of PTEN in GSC. In vivo transient depletion of PRMT5 decreased intracranial tumor size and growth rate in mice implanted with both primary tumor derived GSC and non-GSC.
CONCLUSION: This is the first study to identify PTEN as a potential downstream target of PRMT5 and vital to support both mature and immature GBM tumor cell populations.
Citation Format: Yeshavanth Kumar Banasavadi-Siddegowda, Luke Russell, Jianying Zhang, Vrajesh A. Karkhanis, Jaime Imitola, Robert Baiocchi, Balveen Kaur. PRMT5-PTEN molecular pathway regulates senescence and self-renewal of Glioblastoma stem-like cells. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2845.