1151 DIRECT ANTITUMOR EFFECT OF BACILLUS CALMETTE-GUERIN IN HIGH GRADE UROTHELIAL CANCER CELLS WHICH EXPRESS VLA5 (ALPHA 5 BETA 1 INTEGRIN)

Abstract

You have accessJournal of UrologyBladder Cancer: Basic Research III1 Apr 20101151 DIRECT ANTITUMOR EFFECT OF BACILLUS CALMETTE-GUERIN IN HIGH GRADE UROTHELIAL CANCER CELLS WHICH EXPRESS VLA5 (ALPHA 5 BETA 1 INTEGRIN) Tomoyuki Kato, Mayu Yagi, Atsushi Yamagishi, Noriyuki Hosoya, Toshihiko Sakurai, Hayato Nishida, Sei Naito, Masaaki Tsukigi, Hisashi Kawazoe, Akinori Muto, Akira Nagaoka, and Yoshihiko Tomita Tomoyuki KatoTomoyuki Kato More articles by this author , Mayu YagiMayu Yagi More articles by this author , Atsushi YamagishiAtsushi Yamagishi More articles by this author , Noriyuki HosoyaNoriyuki Hosoya More articles by this author , Toshihiko SakuraiToshihiko Sakurai More articles by this author , Hayato NishidaHayato Nishida More articles by this author , Sei NaitoSei Naito More articles by this author , Masaaki TsukigiMasaaki Tsukigi More articles by this author , Hisashi KawazoeHisashi Kawazoe More articles by this author , Akinori MutoAkinori Muto More articles by this author , Akira NagaokaAkira Nagaoka More articles by this author , and Yoshihiko TomitaYoshihiko Tomita More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2010.02.650AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Intravesical instillation of Bacillus Calmette-Guerin (BCG) is an effective treatment for superficial high grade bladder cancer. Although both immunological and direct effects on tumor cells have been proposed, the complete mechanisms for its effect are not fully understood. Presence of fibronectin has been shown to be necessary for binding and internalization of BCG into tumor cells to exert direct effect on them. We have previously demonstrated the correlation between high expression of fibronectin receptor VLA5 (alpha 5 beta 1 integrin) and high malignant potential of urothelial cancer (UC). Here, we assessed the direct antitumor effects of BCG for UC cell lines which beard various amount of VLA5 on the cell surface. METHODS The human UC cell lines (T24, HT1376 and RT4) and Tokyo 172 BCG strain (Immunobladder, Japan BCG Laboratory), BCG cell wall skeleton (BCG-CWS SMP105, Dainippon Sumitomo Pharma) were used in this study. Viability of cell lines was evaluated with crystal violet stainig assay. Fluorescence of apoptotic nuclei stained with Propidium Iodide (PI) was measured with a FACScan. DNA synthesis was evaluated with BrDU incorporation assay. RESULTS First, expression of VLA5 on the surface of cell lines was checked. T24 and HT1376, high grade UC, beard large amount of VLA5 on the cell surface and RT4, a low grade UC, had traces of VLA5. Treatment with BCG resulted in dose dependent decrease of relative viability in T24 (p<0.0001) and HT1376 (p<0.0001). This effect was partially reversed by coculturing cells with VLA5 blocking antibody. In RT4, viability was not altered by treatment with BCG. Sub-G1 fraction of PI stained T24 increased from less than 1% (untreated) to more than 4% (1 mg/ml of BCG) after exposure to BCG and it suppressed BrDU incorporation (p=0.004) in T24 cells. Autoclaved killed BCG also demonstrated cell growth retardation effect in T24 (p<0.0001) and HT1376 (p<0.0001). BCG-CWS SMP105 also delayed T24 and HT1376 cell growth (p<0.0001). CONCLUSIONS These findings suggest that BCG exerts direct antitumor effect on UC cells via VLA5 with induction of apoptosis and inhibition of DNA synthesis. Moreover, killed BCG and BCG cell wall skeleton were able to exert similar effect making this approach attractive for clinical application where potentially serious adverse effect of viable BCG can be avoided while maintaining antitumor effect using killed BCG or cell extracts. Yamagata, Japan© 2010 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 183Issue 4SApril 2010Page: e445-e446 Advertisement Copyright & Permissions© 2010 by American Urological Association Education and Research, Inc.MetricsAuthor Information Tomoyuki Kato More articles by this author Mayu Yagi More articles by this author Atsushi Yamagishi More articles by this author Noriyuki Hosoya More articles by this author Toshihiko Sakurai More articles by this author Hayato Nishida More articles by this author Sei Naito More articles by this author Masaaki Tsukigi More articles by this author Hisashi Kawazoe More articles by this author Akinori Muto More articles by this author Akira Nagaoka More articles by this author Yoshihiko Tomita More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...