MP61-15 CLOSTRIDIUM PERFRINGES ENTEROTOXIN AS A POTENTIAL THERAPEUTIC FOR INTRAVESICAL TREATMENT OF BLADDER CANCER

Abstract

You have accessJournal of UrologyBladder Cancer: Basic Research & Pathophysiology II1 Apr 2016MP61-15 CLOSTRIDIUM PERFRINGES ENTEROTOXIN AS A POTENTIAL THERAPEUTIC FOR INTRAVESICAL TREATMENT OF BLADDER CANCER Victor Romanov, Wayne Waltzer, Terry Whyard, Olga Povcher, April Szafran, and Theodore Gabig Victor RomanovVictor Romanov More articles by this author , Wayne WaltzerWayne Waltzer More articles by this author , Terry WhyardTerry Whyard More articles by this author , Olga PovcherOlga Povcher More articles by this author , April SzafranApril Szafran More articles by this author , and Theodore GabigTheodore Gabig More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2016.02.889AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES The current intravesical treatment of bladder cancer (BC) is limited to a few chemotherapeutic drugs that shows imperfect effectiveness and are associated with some serious clinical complications. Thus, there is an urgent need for identification of alternative therapies, especially for patients with high-risk non-muscle invasive BC. Clostridium perfringens enterotoxin (CPE), cytolytic protein binds to its receptors: claudin 3 and 4 that expressed in epithelial cells. This binding is followed by pore formation in cell membranes of targeted cells that in turn causes rapid cell death. Claudin 4 is present in bladder urothelium and this expression is substantially elevated in some forms of BC. In addition, binding of CPE to claudins increases membrane permeability that creates conditions for drugs penetration of urothelium and better accession of the tumor. Therefore, we evaluated CPE as a potential candidate for intravesical treatment of BC using an in vitro cellular model. METHODS We examined the cytotoxic efficiency of CPE against BC cells using an array of established cell lines and primary 2 and.3D cultures of cells derived from the surgical samples using in vitro cell viability assay. To better elucidate cellular mechanisms, activated by CPE we synthesized the receptor-binding domain of the enterotoxin (C-CPE), compared its cytotoxic activity with full CPE and examined claudin 4 expression and intracellular localization after that treatment using immunofluorescence and Western blot techniques RESULTS CPE induced cell death after 1 h in low aggressive RT4 cells, in moderately aggressive 5637 cells and in the primary 3D cultures of BC cells derived from non-muscle invasive tumor. Conversely, non-transformed urothelial cells and cells derived from highly aggressive tumor (T24) survived this treatment. The reason for this resistance to CPE might be the lower expression of CLDNs in these cells or inaccessibility of the receptors for CPE. Indeed, claudin 4 was abundantly expressed in cells that can be destroyed by CPE and was present at much lower level in CPE resistant cells. C-CPE treatment for 48 h did not induce cell death, but declined expression of CLDN4 in RT4 cells. In addition, translocation of claudin 4 from cell periphery was observed at these conditions. CONCLUSIONS These observations shows that after additional preclinical studies CPE can be considered as a potential drug for intravesical treatment of BC because of its ability highly effectively destroy BC cells expressing claudin 4 and low toxicity against normal urothelium. © 2016FiguresReferencesRelatedDetails Volume 195Issue 4SApril 2016Page: e809 Advertisement Copyright & Permissions© 2016MetricsAuthor Information Victor Romanov More articles by this author Wayne Waltzer More articles by this author Terry Whyard More articles by this author Olga Povcher More articles by this author April Szafran More articles by this author Theodore Gabig More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...