356 SECRETED FRIZZLED-RELATED PROTEIN-5 (SFRP-5) IS EPIGENETICALLY DOWNREGULATED AND FUNCTIONS AS A TUMOR SUPPRESSOR IN RENAL CELL CANCER

Abstract

You have accessJournal of UrologyKidney Cancer: Basic Research III1 Apr 2010356 SECRETED FRIZZLED-RELATED PROTEIN-5 (SFRP-5) IS EPIGENETICALLY DOWNREGULATED AND FUNCTIONS AS A TUMOR SUPPRESSOR IN RENAL CELL CANCER Kazumori Kawakami, Soichiro Yamamura, Hiroshi Hirata, Koji Ueno, Sharanjot Saini, Shahana Majid, Yuichiro Tanaka, Ken Kawamoto, Hideki Enokida, Masayuki Nakagawa, and Rajvir Dahiya Kazumori KawakamiKazumori Kawakami San Francisco, CA More articles by this author , Soichiro YamamuraSoichiro Yamamura San Francisco, CA More articles by this author , Hiroshi HirataHiroshi Hirata San Francisco, CA More articles by this author , Koji UenoKoji Ueno San Francisco, CA More articles by this author , Sharanjot SainiSharanjot Saini San Francisco, CA More articles by this author , Shahana MajidShahana Majid San Francisco, CA More articles by this author , Yuichiro TanakaYuichiro Tanaka San Francisco, CA More articles by this author , Ken KawamotoKen Kawamoto Kagoshima, Japan More articles by this author , Hideki EnokidaHideki Enokida Kagoshima, Japan More articles by this author , Masayuki NakagawaMasayuki Nakagawa Kagoshima, Japan More articles by this author , and Rajvir DahiyaRajvir Dahiya San Francisco, CA More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2010.02.423AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Aberrant activation of the Wingless-type (Wnt) pathway plays a significant role in the carcinogenesis of several human cancers. Secreted frizzled-related protein-5 (sFRP-5) has been identified as one of the Wnt antagonists. The molecular function of sFRP-5 has never been examined in renal cell cancer (RCC). We hypothesize that sFRP-5 is epigenetically down-regulated and functions as a tumor suppressor in RCC. METHODS sFRP-5 expression levels were examined in 22 normal and 24 cancer regions of clinical samples using tissue microarray. sFRP-5 mRNA expression was also checked by TaqMan real time RT-PCR in RCC cell lines. We used bisulfite sequencing to check the methylation status of the sFRP-5 gene promoter. To examine the histone modification, chromatin immunoprecipitation (ChIP) assay was performed. We also established stable cell line (A498) transfected with either empty vector or the full-length sFRP-5 gene. Anchorage-independent colony formation assay, invasion assay and apoptosis analysis were carried out on the transfected A498 cell line. RESULTS Immunohistochemistry of tissue microarray and real time RT-PCR revealed that sFRP-5 was significantly down-regulated in RCC samples and cell lines, respectively. Bisulfite sequencing of the sFRP-5 promoter region showed it to be densely methylated. The sFRP-5 expression was restored and the acetylation of H3 and H4 histones associated with the sFRP-5 promoter region were significantly increased after treatment with demethylation agent (5-Aza-dc) and histone deacetylase inhibitor (TSA), respectively. Significant inhibition of anchorage-independent colony formation and cell invasion in sFRP-5 transfected cells compared to empty vector transfected cells were observed. In addition, the sFRP-5 transfection significantly induced apoptosis in RCC cells. CONCLUSIONS This is the first report documenting that the sFRP-5 is down-regulated by promoter methylation and histone acetylation and functions as a tumor suppressor gene by inducing apoptosis in RCC cells. © 2010 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 183Issue 4SApril 2010Page: e141 Advertisement Copyright & Permissions© 2010 by American Urological Association Education and Research, Inc.MetricsAuthor Information Kazumori Kawakami San Francisco, CA More articles by this author Soichiro Yamamura San Francisco, CA More articles by this author Hiroshi Hirata San Francisco, CA More articles by this author Koji Ueno San Francisco, CA More articles by this author Sharanjot Saini San Francisco, CA More articles by this author Shahana Majid San Francisco, CA More articles by this author Yuichiro Tanaka San Francisco, CA More articles by this author Ken Kawamoto Kagoshima, Japan More articles by this author Hideki Enokida Kagoshima, Japan More articles by this author Masayuki Nakagawa Kagoshima, Japan More articles by this author Rajvir Dahiya San Francisco, CA More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...