Cantharidin-induced cytotoxicity and cyclooxygenase 2 expression in human bladder carcinoma cell line.
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.
Huan
Steven Kuan-Hua
SK
.Division of Urology, Department of Surgery, Chi-Mei Medical Center, Tainan, Taiwan, ROC.
Lee
Hao-Hsien
HH
Liu
Der-Zen
DZ
Wu
Chien-Chih
CC
Wang
Ching-Chiung
CC
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
D000255:Adenosine Triphosphate; D051546:Cyclooxygenase 2; D002193:Cantharidin; D015232:Dinoprostone