PD33-09 MIR-135A IS ASSOCIATED WITH CRYPTORCHIDISM INFERTILITY THROUGH SUPPRESSION OF FOXO1 IN SPERMATOGONIAL STEM CELLS

Abstract

You have accessJournal of UrologyStem Cell Research: Stem Cell Research I1 Apr 2018PD33-09 MIR-135A IS ASSOCIATED WITH CRYPTORCHIDISM INFERTILITY THROUGH SUPPRESSION OF FOXO1 IN SPERMATOGONIAL STEM CELLS Yoshinobu Moritoki, Kentaro Mizuno, Hideyuki Kamisawa, Satoshi Kurokawa, Akihiro Nakane, Tetsuji Maruyama, Yutaro Hayashi, and Takahiro Yasui Yoshinobu MoritokiYoshinobu Moritoki More articles by this author , Kentaro MizunoKentaro Mizuno More articles by this author , Hideyuki KamisawaHideyuki Kamisawa More articles by this author , Satoshi KurokawaSatoshi Kurokawa More articles by this author , Akihiro NakaneAkihiro Nakane More articles by this author , Tetsuji MaruyamaTetsuji Maruyama More articles by this author , Yutaro HayashiYutaro Hayashi More articles by this author , and Takahiro YasuiTakahiro Yasui More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2018.02.1564AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Spermatogonial stem cells (SSCs) function as a life-long spermatogenesis reserve. Self-renewal and stem maintenance are foundational characteristics of SSCs. To maintain these cellular characteristics, the regulation of genome transcription is mandatory, although the basis of this mechanism remains unknown. Recently, small mRNA, called microRNA (miRNA), consisting of 18–25 nucleotide bases have been recognized as key transcription regulators. The effect involves more than one-third of all transcription regulation. We hypothesized that miRNAs function as one of the key SSC regulators and are likely associated with SSC differentiation and thus aimed to find the miRNAs expressing in SSCs and its target mRNAs. METHODS We used a cryptorchid rat testes model of SSC disturbance. The model was generated using intra-abdominal injection of flutamide (7.5 mg/rat) into pregnant Sprague-Dawley rats. Normal testes, unilateral undescended testes (UDT), and contralateral descended testes (DT) were extirpated on postnatal day 9, when two types of SSCs (gonocytes and spermatogonia) co-existed and gonocytes began differentiation into spematogonia. A microarray examining DT and UDT focused on miR-135a, which exhibited lower expression in UDT. In situ hybridization (ISH) was used for the detection of the localization of miR-135a and quantitative polymerase chain reaction (qPCR) to determine the organ specificity of the gene. We then searched the miR-135a target genes using a computer program, followed by the luciferase assay to demonstrate the suppression effect of miR-135a in vitro. RESULTS qPCR revealed that miR-135a was 8.3–21.3 times over-expressed in the testes than in other organs; ISH showed miR-135a localized in SSCs. In silico analysis identified FOXO1 as a putative target gene of miR-135a. FOXO1 has a sequence complementary to miR-135a's seed sequence at its 3' untranslated region. FOXO1 localized in SSCs, and a luciferase assay demonstrated that miR-135a directly suppressed FOXO1 expression in mouse GC-1 cells. CONCLUSIONS We demonstrated that miR-135a is associated with the maintenance of SSCs and that its putative target gene is FOXO1. Because FOXO1 is already proven necessary for maintenance of SSCs and we proved that SSCs are reduced in UDT, we hypothesized that miR-135a was lowered to facilitate the active FOXO1 expression, leading to SSC maintenance. Thus, miR-135a is associated with SSC maintenance through regulation of FOXO1 expression. © 2018FiguresReferencesRelatedDetails Volume 199Issue 4SApril 2018Page: e653-e654 Advertisement Copyright & Permissions© 2018MetricsAuthor Information Yoshinobu Moritoki More articles by this author Kentaro Mizuno More articles by this author Hideyuki Kamisawa More articles by this author Satoshi Kurokawa More articles by this author Akihiro Nakane More articles by this author Tetsuji Maruyama More articles by this author Yutaro Hayashi More articles by this author Takahiro Yasui More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...