MP72-11 TARGETING SUNITINIB RESISTANT CELLS BY TUMOR SUPPRESSIVE MIRNA-99A-3P THROUGH RIBONUCLEOTIDE REDUCTASE REGULATION IN CLEAR CELL RENAL CELL CARCINOMA

Abstract

You have accessJournal of UrologyKidney Cancer: Basic Research & Pathophysiology II1 Apr 2018MP72-11 TARGETING SUNITINIB RESISTANT CELLS BY TUMOR SUPPRESSIVE MIRNA-99A-3P THROUGH RIBONUCLEOTIDE REDUCTASE REGULATION IN CLEAR CELL RENAL CELL CARCINOMA Youichi Osako, Hirofumi Yoshino, Takashi Sakaguchi, Satoshi Sugita, Shuichi Tatarano, Takashi Yamane, Hideki Enokida, and Masayuki Nakagawa Youichi OsakoYouichi Osako More articles by this author , Hirofumi YoshinoHirofumi Yoshino More articles by this author , Takashi SakaguchiTakashi Sakaguchi More articles by this author , Satoshi SugitaSatoshi Sugita More articles by this author , Shuichi TataranoShuichi Tatarano More articles by this author , Takashi YamaneTakashi Yamane More articles by this author , Hideki EnokidaHideki Enokida More articles by this author , and Masayuki NakagawaMasayuki Nakagawa More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2018.02.2295AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Sunitinib is the most common targeting drug for metastatic renal cell carcinoma (RCC), however resistance to sunitinib is a large problem in clinical aspect. In this study, we focused on miR-99a-3p, which showed decreased expression in sunitinib-resistant RCC based on previous screening analyses, and we investigated the mechanism of sunitinib tolerance associated with miR-99a-3p and the molecular network controlled by miR-99a-3p. METHODS Expression levels of miR-99a-3p and its candidate target genes in the RCC cell lines (786-o, ACHN, and our sunitinib-resistant cell (SU-R-786-o)) and RCC clinical specimens were evaluated by qRT-PCR. For the gain of function study, cell proliferation, apoptosis, and colony formation assay were performed in miR-99a-3p transfected RCC cell lines. Putative target genes were determined by the analyses with publically available database such as GEO and TargetScan, as well as RNA sequencing expression analysis using SU-R-786-o. Loss of functional studies of the target gene was performed using si-RNA. Overall survival between high and low expression of the target gene was analyzed by the Kaplan-Meier method using the database of The Cancer Genome Atlas (TCGA). RESULTS The expression levels of miR-99a-3p were down regulated in RCC clinical specimens and the RCC cell lines compared to normal kidneys. In addition, its expression in SU-R-786-o was much lower compared to the parent cell. Restoration of miR-99a-3p in the RCC cells including SU-R-786-o significantly inhibited cell proliferation (p<0.0001) through induction of apoptosis (p<0.0001). RRM2, involved in the synthesis of deoxynucleotides that is necessary for polymerization and repair of DNA, was identified as a direct target by miR-99a-3p based on target analyses. Loss of functional studies using si-RRM2 showed that cell proliferation was significantly inhibited through induction of apoptosis especially in SU-R-786-o (p<0.0001). Kaplan-Meier analysis revealed that the patients (n= 534) with high expression of RRM2 showed lower overall survival time than those with low expression according to the TCGA database (p<0.0001). CONCLUSIONS miR-99a-3p might have tumor suppressive function through induction of cell apoptosis in sunitinib-resistant RCC cells. To the best of our knowledge, this is the first report demonstrating that miR-99a-3p directly regulate RRM2. The identification of novel target gene regulated by tumor-suppressive miR-99a-3p in sunitinib resistant RCC cells may lead to a better understanding of resistant mechanism and the development of new therapeutic strategies. © 2018FiguresReferencesRelatedDetails Volume 199Issue 4SApril 2018Page: e956 Advertisement Copyright & Permissions© 2018MetricsAuthor Information Youichi Osako More articles by this author Hirofumi Yoshino More articles by this author Takashi Sakaguchi More articles by this author Satoshi Sugita More articles by this author Shuichi Tatarano More articles by this author Takashi Yamane More articles by this author Hideki Enokida More articles by this author Masayuki Nakagawa More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...