bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 341: Investigating a novel GPCR ITIM motif in regulating Shp2 binding, signaling, and migration
Authors: Paulukinas Ryan D. , Belcastro Lili T. , Moore Catherine C. 
Published: July 2017

Abstract
Aberrant expression of CXCR4, a chemokine G protein-coupled receptor (GPCR), promotes a migratory and invasive phenotype during breast cancer metastasis, however the mechanism is unknown. Here we investigate the role of CXCR4 tyrosine phosphorylation within a novel ITIM motif. Following activation, CXCR4 is normally phosphorylated on Ser/Thr residues, which promotes receptor desensitization and internalization. We found previously that Ser/Thr phosphorylation of CXCR4 is delayed upon SDF gradient sensing, and correlates with sustained signaling to SHP2, a protein that drives hyperproliferation and invasion of breast cancer. Since SHP2 is known to be recruited to tyrosine phosphorylated ITIM motifs (immmunoreceptor tyrosine-based inhibitory consensus motifs), we investigated if CXCR4 contains an ITIM motif, and if tyrosine phosphorylation within this motif regulates SHP2 binding, signaling, and migration. Specifically, we assessed 1) if CXCR4 is tyrosine phosphorylated as measured by recombinant phosphatase assay, phospho-Ab development, and tyrosine mutagenesis (YF); 2) if tyrosine mutagenesis alters CXCR4 membrane localization, internalization, and SDF gradient sensing, by ELISA; 3) if tyrosine mutagenesis disrupts CXCR4 interaction with SHP2, by co-IP; 4) if tyrosine mutagenesis alters CXCR4 sustained signaling to SHP2, by Western; and 5) if tyrosine mutation (YF) within the novel ITIM motif in CXCR4 alters migration of metastatic breast cancer cells, by transwell motility assays. Our results demonstrate that CXCR4 phosphorylation is sensitive to recombinant tyrosine phosphatase treatment and tyrosine mutagenesis, suggesting that CXCR4 is indeed tyrosine phosphorylated within the ITIM motif. We determined that while tyrosine phosphorylation within the ITIM motif is not required for CXCR4 membrane localization, internalization, or SDF gradient sensing, it does regulate CXCR4 binding and signaling to SHP2. Investigating the role in CXCR4 mediated migration is on going. To date, our data support a working model that tyrosine phosphorylation of CXCR4 within an ITIM motif is critical for binding to SHP2 and transducing sustained signaling to SHP2. These data have implications on aggressive breast cancers with dysregulated CXCR4 and SHP2. These studies were supported by NIH grant GM-097718, PA Department of Health grant SAP4100057688, and the Milton Lev Memorial Faculty Research Fund.
Citation Format: Ryan D. Paulukinas, Lili T. Belcastro, Catherine C. Moore. Investigating a novel GPCR ITIM motif in regulating Shp2 binding, signaling, and migration [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 341. doi:10.1158/1538-7445.AM2017-341
Abstract 3414: Novel MGMT variant association in Mexican patients with astrocytoma
Authors: Gomez-Flores-Ramos Liliana , Wegman-Ostrosky Talia 
Published: July 2017

Abstract
Introduction: Astrocytomas are the most common and lethal brain tumors with a median survival of 15 months. Different biomarkers have arisen to classify and treat this type of tumors; one of these markers is MGMT. The methylation status of this gene is a prognostic and predictive factor. The MGMT (O-6-Methylguanine-DNA Methyltransferase) is involved in the cellular response to the effects of O6-methylguanine (O6-MeG) in DNA. Repairs alkylated guanine in DNA by transferring the alkyl group at the O-6 position to a cysteine residue in the enzyme. The dysregulation of this methylation is critical in the development of certain cancers.
Objective: To identify germinal MGMT gene variations in patients with astrocytoma.
Material and methods: 55 randomly selected Mexican patients diagnosed with astrocytoma between 2008-2014 were consented to perform the molecular analysis of the whole gene and 5´UTR and 3´UTR regions of MGMT at Ion Torrent platform. Each amplified region had a depth of minimum 1500x. Ion Reporter software was used to analyze the genetic variants and using Integrative Genomic Viewer we confirmed that each variant had a Phred higher than 25. Genotypic frequencies were compared with HapMapMex and Mexican ancestry population from the 1000 Genomes project.
Results. In lymphocytes DNA, eight genetic variants were found, and two of them were statistically significant risk factors: rs7896488 alternative allele A with a frequency of 15% in patients with astrocytoma, and only 4% of the control group (OR=5.53, IC 1.96-15.59 p = 0.0007) and rs2308326 ancestral allele C, where 93% of the patients were carriers of allele C in contrast with 73% of controls (OR=5.39, IC 2.29-12.69 p = 0.000019). These variants are non-coding single nucleotide polymorphisms, rs7896488 is a 3' UTR genetic variant, while rs2308326 is an intronic variant.
Conclusion: Our study found two new risk SNV for Astrocytoma in a Mexican population.
Citation Format: Liliana Gomez-Flores-Ramos, Talia Wegman-Ostrosky. Novel MGMT variant association in Mexican patients with astrocytoma [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 3414. doi:10.1158/1538-7445.AM2017-3414
Abstract 3424: Role of miR-489 in mammary gland development and Her2 mediated tumorigenesis
Authors: Patel Yogin , Soni Mithil , Liu Shou , Chen Hexin 
Published: July 2017

Abstract
HER2 overexpression is linked with poor prognosis and outcome in breast cancer. In our previous study, we have found miR-489 was specifically down regulated by HER2 overexpression. Restoration of miR-489 in multiple breast cancer cell lines significantly inhibited cell growth in vitro and decreased tumor growth in xenograft mice. To study role of miR-489 in Her2 mediated tumorigenesis, for the first time we generated MMTV-miR-489 transgenic mice, which overexpress miR-489 specifically in mammary gland. Our qRT-PCR data has confirmed transgenic mice have significantly more miR-489 expression than FVB mice. We used western blot to further validate our model system and found significant downregulation of miR-489 targets DEK and PTPN11. To find out whether miR-489 has any role in mammary gland development, mammary gland whole mount was performed from wild type FVB mice and MMTV-miR-489 mice at different age. Mammary gland from MMTV-miR-489 mice demonstrated reduction in growth at early age. Our immunohistochemistry staining demonstrated significantly reduction in Ki-67 positive cells in MMTV-miR-489 mammary gland at early age, further confirming reduced growth in MMTV-miR-489 mice. However, we found no significant effect on weight of litters of MMTV-miR-489 female since after 8-week mammary gland was able to recover growth. To find out effect of miR-489 overexpression on Her2 mediated tumorigenesis, we generated double transgenic mice MMTV-Her2/miR-489 by crossing MMTV-miR-489 mice with MMTV-Her2 mice. We have observed significant delay in tumor onset and reduced tumor growth in MMTV-Her2/ miR-489 mice compare to MMTV-Her2 mice. We have also observed less number of metastatic site in lung by performing H and E staining of lung. Our IHC data showed reduction in PTPN11 and DEK in miR-489 overexpress mammary tumor. Surprisingly, we found significant reduction of miR-489 expression in mammary tumors of MMTV-Her2-miR-489 when compared with normal mammary gland of same mice. Overall, our results indicated miR-489 overexpression suppresses mammary gland development at early age, reduced mammary tumorigenesis and decrease lung metastasis by targeting PTPN11 and DEK.
Citation Format: Yogin Patel, Mithil Soni, Shou Liu, Hexin Chen. Role of miR-489 in mammary gland development and Her2 mediated tumorigenesis [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 3424. doi:10.1158/1538-7445.AM2017-3424
Abstract 3428: Tamoxifen differentially regulates miR-29b-1 and miR-29a depending on endocrine sensitivity in breast cancer
Authors: Muluhngwi Penn , Klinge Carolyn M. 
Published: July 2017

Abstract
Acquired endocrine-resistance occurs in ~ 40% of estrogen receptor α (ERα)+ breast cancer patients after tamoxifen (TAM) or aromatase inhibitor therapy. MicroRNAs (miRs) are dysregulated in breast cancer, but their contribution to endocrine-resistance is not yet completely understood. Microarray analysis of miRNAs in TAM-sensitive MCF-7 versus TAM-resistant LY2 breast cancer cells (derived from MCF-7 cells) identified differential regulation of miR-29b-1 and miR-29a. miR-29a and miR-29b-1, which are co-transcribed as a single primary-miR, were repressed by TAM in MCF-7 and stimulated by TAM in LY2 cells. We confirmed these observations by real time qPCR in MCF-7 and LY2 cells and observed that 4-OH-TAM (4-OHT) also downregulated miR-29b-1/a in LCC2 and LCC9 endocrine-resistant cells. These changes were at the primary transcriptional level. The role of these two miRs in endocrine-resistant breast cancer is unknown. We tested the hypothesis that the TAM-stimulated increase in miR-29b-1/a promotes endocrine-resistance by downregulating targets that contribute to TAM’s antiproliferative/pro-apoptotic activity. Our goals were to: 1) Determine if ERα was responsible for TAM regulation of miR-29b-1/a expression; 2) Determine the functional role(s) of miR-29b-1/a; 3) Identify specific miR-29b-1/a target genes that are differentially regulated by 4-OHT in MCF-7 versus LCC9 and LY2 cells. Knockdown of ERα blocked 4-OHT inhibition of miR-29b-1/a in MCF-7 and 4-OHT simulation of miR-29-b-1/a transcription in LCC9 and LY2 cells. Transient over-expression of miR-29b-1/a inhibited proliferation of MCF-7, LCC9, and LY2 cells and decreased migration and colony formation of LY2 cells. Repression of miR-29b-1/a has no significant effect on MCF-7, LCC9, or LY2 cell proliferation. Repression of miR-29-b-1/a did not sensitize the TAM-resistant cells to growth inhibition by 4-OHT. We observed that the bona fide miR-29 target gene, DICER1, was inhibited by 4-OHT in LY2 cells and anti-miR29b-1 or anti-miR-29a decreased the suppression of DICER1 by 4-OHT. These data suggest that 4-OHT-ERα increases miR-29b-1/a which target and downregulate DICER 1 in endocrine resistant breast cancer cells. Future studies will identify other targets of miR-29b-1/a to better understand the pathways leading to acquired endocrine resistance.
Citation Format: Penn Muluhngwi, Carolyn M. Klinge. Tamoxifen differentially regulates miR-29b-1 and miR-29a depending on endocrine sensitivity in breast 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 3428. doi:10.1158/1538-7445.AM2017-3428
Abstract 3429: Oncogenic function of miR-23b-3p in hepatocellular carcinoma
Authors: Tanabe Hiroshi , Hayashi Masamichi , Sugimoto Hiroyuki , Kurimoto Keisuke , Hirabayashi Sho , Kanda Mitsuro , Takami Hideki , Niwa Yokiko , Iwata Naoki , Kobayashi Daisuke , Tanaka Chie , Yamada Suguru , Nakayama Goro , Koike Masahiko , Fujii Tsutomu , Fujiwara Michitaka , Kodera Yasuhiro 
Published: July 2017

Abstract
Background: miR-23b has been identified as various cancer-related biomarkers. Interestingly, it works as an oncogenic miRNA in lymphoma, renal cancer and glioma, while it works as a tumor suppressor miRNA in pancreatic cancer, bladder cancer and prostate cancer (Donadeli M et al, Cancer Lett, 2014). We have previously reported miR-23b-3p as a oncomiR in NSCLCs (Begum S, Hayashi M et al, Sci Rep, 2015). To find the correlation to other carcinogenesis, we focused on miR-23b function in hepatocellular carcinoma (HCC).
Methods: miR-23b-3p expression was examined in 9 HCC cell lines (SK-Hep1, HuH2, HLE, PLC/PRF/5, HuH1, HuH7, HLF, Hep3B, HepG2). The downstream of miR-23b-3p overexpression was examined by Cancer Pathway Finder (Qiagen). Results were applied to 125 clinical HCC samples (2002-2011 surgically resected).
Results: Transfection experiments were performed for HepG2 (miR-23b-3p highly expressed) by siRNA and for SK-Hep1 (lowly expressed) by miRNA mimic. Cancer cell proliferation was activated by miR-23b-3p overexpression, and diminished by its inhibition. In order to find the associated genes, miR-23b-3p overexpressed SK-Hep1 cells were compared with parental SK-Hep1 cells by global gene expression analysis. ANGP1, ERCC5 and G6PD genes were upregulated, while KDR, WEE1, OCLN genes were downregulated. We also detected additional two genes (AUH and MICU3) by TargetScan Release 5.2. Clinical HCC samples were divided into miR-23b-3p upregulated 48 cases (38%) and downregulated 77 cases (62%). Upregulated cases were correlated with aged patients (P=0.015), capsule invasion positive (P=0.039) and serosal invasion positive (P=0.049). Also, they showed significantly poor recurrence free survival (HR=1.64, P=0.037, 95%CI:1.03-2.59) and overall survival (HR=3.10, P=0.001, 95%:1.57-6.29) in multivariable analysis.
Conclusion: miR-23b-3p increased the HCC cell proliferation, and indicated the invasive type of HCCs. It functions as a oncogenic biomarker in HCCs and might be a therapeutic target.
Citation Format: Hiroshi Tanabe, Masamichi Hayashi, Hiroyuki Sugimoto, Keisuke Kurimoto, Sho Hirabayashi, Mitsuro Kanda, Hideki Takami, Yokiko Niwa, Naoki Iwata, Daisuke Kobayashi, Chie Tanaka, Suguru Yamada, Goro Nakayama, Masahiko Koike, Tsutomu Fujii, Michitaka Fujiwara, Yasuhiro Kodera. Oncogenic function of miR-23b-3p 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 3429. doi:10.1158/1538-7445.AM2017-3429
Abstract 3446: Melatonin suppresses hepatocellular carcinoma progression via lncRNA-CPS1-IT-mediated HIF-1α inactivation
Authors: Wang Tong Hong , Wu Chi Hao , Yeh Chau Ting , Liang Kung Hao , Hsueh Chuen , Chen Chi Yuan 
Published: July 2017

Abstract
Background: Melatonin, the main pineal hormone that relays light/dark cycle information to the circadian system, was recently reported to have intrinsic antitumor activity in various cancers. However, the detailed regulatory mechanisms associated with antitumor activity of melatonin are not well understood yet. Moreover, limited studies have addressed the role of melatonin in hepatocellular carcinoma (HCC), the major life-threatening malignancy for both sexes in Taiwan. Hence, in this study, we investigated the antitumor activity of melatonin on HCC and explored its regulatory mechanism.
Methods: Human hepatoma cell lines HepG2 and Huh7 were treated with melatonin followed by functional assays to dissect antitumor effect of melatonin in HCC. The whole transcriptome sequence analysis was performed to explore the long non-coding RNAs (lncRNAs) involved in the anti-HCC activity of melatonin. Further, quantitative RT-PCR, western blot, immunohistochemistry assays, and in vivo animal model experiments were performed to elucidate the regulatory mechanism of lncRNAs in melatonin-mediated HCC suppression.
Results: Melatonin significantly inhibited cell proliferation, migration, and invasion capacity of HCC cell lines, while the expression of transcription factor FOXA2 was significantly induced in cells treated with melatonin. The increase in expression of FOXA2 resulted in upregulation of lncRNA-CPS1-IT1 expression, which in turn reduced binding and activation of Hsp90 with HIF-1α. The inactivation of HIF-1α resulted in the suppression of epithelial-mesenchymal transition (EMT) progression and HCC metastasis. Furthermore, the results of the in vivo animal model experiments also validated the tumor-suppressor role of melatonin via a reduction in tumor growth.
Conclusions: Taken together, our findings suggested that melatonin inhibited HCC progression by modulating lncRNA-CPS1-IT1-mediated EMT suppression and further supported melatonin as a promising therapeutic agent for the treatment of HCC.
Note: This abstract was not presented at the meeting.
Citation Format: Tong Hong Wang, Chi Hao Wu, Chau Ting Yeh, Kung Hao Liang, Chuen Hsueh, Chi Yuan Chen. Melatonin suppresses hepatocellular carcinoma progression via lncRNA-CPS1-IT-mediated HIF-1α inactivation [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 3446. doi:10.1158/1538-7445.AM2017-3446
Abstract 3452: The cohesin subunit STAG1 is a hardwired genetic dependency of STAG2 mutant cancer cells
Authors: Lelij Petra Van Der , Lieb Simone , Jude Julian , Wutz Gordana , Pereira Catarina , Falkenberg Katrina , Ban Jozef , Kovar Heinrich , Waldman Todd , Real Francisco , Pearson Mark , Kraut Norbert , Peters Jan-Michael , Zuber Johannes , Petronczki Mark P. 
Published: July 2017

Abstract
Recent genome analyses have identified recurrent mutations in subunits of the cohesin complex in human cancer. Cohesin is a chromosomal factor that is essential for sister chromatid cohesion and cell division and that contributes to gene regulation and DNA repair. Deleterious mutations in the cohesin subunit STAG2 have been detected in about 20% of bladder cancer, 15% of Ewing sarcoma and 6% of AML/MDS patients. The mechanistic involvement of cohesin mutations in the pathogenesis of human malignancies is currently under active investigation. We hypothesized that the loss of STAG2 could alter the properties and functionalities of the cohesin complex leading to unique vulnerabilities of STAG2 mutant cells. Using CRISPR/Cas9 and RNAi in isogenic solid cancer and leukemic models we identified STAG1, a STAG2 paralog, as a strong and clean genetic vulnerability of STAG2 mutant cells. Mechanistically, STAG1 loss abrogates sister chromatid cohesion specifically in STAG2 mutant but not wild-type cells leading to mitotic catastrophe, defective cell division and apoptosis. STAG1 inactivation inhibits the proliferation of disease relevant STAG2 mutant but not wild-type bladder cancer and Ewing sarcoma cell lines. Restoration of STAG2 expression in a mutant bladder cancer model alleviates the dependence on STAG1. Our results demonstrate that the cohesin subunits STAG1 and STAG2 act redundantly to support sister chromatid cohesion and cell viability in human cells. We have identified STAG1 as a hardwired, context independent vulnerability of STAG2 mutant cancers. Specific synthetic lethalities elicited by recurrent cohesin mutations in human tumors hold the promise for the development of selective therapeutics.
Citation Format: Petra Van Der Lelij, Simone Lieb, Julian Jude, Gordana Wutz, Catarina Pereira, Katrina Falkenberg, Jozef Ban, Heinrich Kovar, Todd Waldman, Francisco Real, Mark Pearson, Norbert Kraut, Jan-Michael Peters, Johannes Zuber, Mark P. Petronczki. The cohesin subunit STAG1 is a hardwired genetic dependency of STAG2 mutant cancer cells [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 3452. doi:10.1158/1538-7445.AM2017-3452
Abstract 3455: Cystatin C decreases proliferation of melanoma cells by affecting mitosis length
Authors: Wallin Hanna , Alm Kersti , Abrahamson Magnus 
Published: July 2017

Abstract
Cystatin C is a small secreted protein, produced by most cells in the body and found in significant quantities in all body fluids. It is the major inhibitor of extracellular cysteine protease activity in mammals because of its rapid binding to virtually all known cysteine proteases of families C1 (cysteine cathepsins) and C13 (mammalian legumain). Cystatin C has also been shown to inhibit viral replication within cells and display protective effects against cancer cell invasion. The protein has recently been shown to get internalized into cancer cells, providing an explanation to possible intracellular effects of the inhibitor.
The purpose of the present study was to elucidate possible direct effects of cystatin C on cancer cell growth, by use of holometric imaging to analyze proliferation rate as well as to monitor the mitosis phase in real-time. Human A375 melanoma cells were cultured with and without addition of physiological quantities of cystatin C added to the culture medium (1 micromolar final concentration). The cultures were monitored for up to 3 days in a standard incubator using a HoloMonitor M4 instrument. Settings were optimized to allow accurate counting of cells throughout the experiment by analysis of images captured, revealing an inhibitory effect on overall cell proliferation rate by cystatin C addition to the cultures. To analyze the migration and cell division of individual cells, images were captured at short intervals allowing tracking and monitoring of cell morphology with respect to parameters such as thickness/density and area. Parameters could be set to define start of the mitosis phase indicated by a distinct rounding-up of cells and followed until a natural stop at cytokinesis, whereafter the daughter cells could be continuously tracked. These analyses revealed qualitative differences in the normal migration behavior of the A375 cells under study as a result of cystatin C addition. Moreover, the mitosis phase was considerably prolonged in cells grown in cystatin C containing medium, indicating that the proliferation-inhibiting effect of the protease inhibitor may be through its direct action on proteolytic processes in the actual mitosis phase. This finding justifies in-depth studies on additional cancer cell types to reveal how general the anti-proliferative effect of cystatin C is and how it can be explored to possibly control cancer cell growth and spread. The use of real-time holometric imaging of growing cells should be a most useful tool in such studies.
Citation Format: Hanna Wallin, Kersti Alm, Magnus Abrahamson. Cystatin C decreases proliferation of melanoma cells by affecting mitosis length [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 3455. doi:10.1158/1538-7445.AM2017-3455