title: Cantharidin-induced cytotoxicity and cyclooxygenase 2 expression in human bladder carcinoma cell line.
abstract: Mylabris is used in clinical therapy, but is always accompanied by cystitis. The toxic effects of mylabris on bladder are attributed to its active principle: cantharidin. In the present study, we explored how cantharidin induces cytotoxicity in the bladder. Human bladder carcinoma cell line T 24 cells were used as target cells, and human colon carcinoma HT 29 cells as native cells. Cantharidin exhibited acute cytotoxicity in the T 24 cells, and IC(50) was 21.8, 11.2 and 4.6 microM after treatment for 6, 24 and 48 h, respectively. The cytotoxicity of cantharidin was not significantly enhanced when T 24 cells were treated for a longer time. Moreover, PARP proteins and pro-caspase 3, Bcl-2 were significantly inhibited after cantharidin treatment in T 24 cells. Pretreatment with the caspase 3 inhibitor markedly inhibited cantharidin-induced cell death. Therefore, we suggested that cantharidin could induce apoptosis via active caspase 3 in T 24 cells. When T 24 cells were treated with cantharidin at a low dose, the cell cycle was arrested in the G(2)/M phase. Furthermore, p21(Cip1/Waf1) was enhanced, and cyclin A, B1 and cdk1 decreased. At a high dose (more 12.5 microM), cantharidin could stimulate T 24 cells to deplete a large number of ATP and induce secondary necrosis. In addition, cantharidin also stimulated COX 2 over-expression and PGE(2) production in T 24 cells, in a dose-dependent manner. However, cantharidin also induced apoptosis and G(2)/M phase arrest in HT 29 cells, but did not induce COX 2 over-expression. Therefore, we suggest that cantharidin may induce cystitis through secondary necrosis and COX 2 over-expression.
authors.affiliation: .Division of Urology, Department of Surgery, Chi-Mei Medical Center, Tainan, Taiwan, ROC.
authors.forename: Steven Kuan-Hua
authors.initials: SK
authors.lastname: Huan
authors.forename: Hao-Hsien
authors.initials: HH
authors.lastname: Lee
authors.forename: Der-Zen
authors.initials: DZ
authors.lastname: Liu
authors.forename: Chien-Chih
authors.initials: CC
authors.lastname: Wu
authors.forename: Ching-Chiung
authors.initials: CC
authors.lastname: Wang
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D002193:Cantharidin / Q000633:toxicity*; D045744:Cell Line, Tumor; D051546:Cyclooxygenase 2 / Q000096:biosynthesis*; D015232:Dinoprostone / Q000096:biosynthesis; D004305:Dose-Response Relationship, Drug; D005434:Flow Cytometry; D006801:Humans; D008516:Medicine, Chinese Traditional; D015854:Up-Regulation; D001749:Urinary Bladder Neoplasms / Q000201:enzymology / Q000378:metabolism / Q000473:pathology
chemical_list: D000255:Adenosine Triphosphate; D051546:Cyclooxygenase 2; D002193:Cantharidin; D015232:Dinoprostone