Increase in cytosolic calcium maintains plasma membrane integrity through the formation of microtubule ring structure in apoptotic cervical cancer cells induced by trichosanthin.
This study investigates the role of dysregulated cytosolic free calcium ([Ca(2+)]c) homeostasis on microtubule (MT) ring structure in apoptotic cervical cancer (HeLa) cells induced by trichosanthin (TCS), a type I ribosome inactivating protein (RIP). The TCS-induced decrease in cell viability was significantly enhanced in combination with the specific calcium chelator, EGTA-AM. Sequestration of [Ca(2+)]c markedly disrupted the special MT ring structure. Furthermore, TCS tended to increase LDH release, whereas no significant differences were observed until 48 h of the treatment. In contrast, combined addition of EGTA-AM or colchicine (an inhibitor of tubulin polymerization) significantly reinforced LDH release. The data suggest that TCS-elevated [Ca(2+)]c maintains plasma membrane integrity via the formation of the MT ring structure in apoptotic HeLa cells.
Wang
Ping
P
Medical School, Ningbo University, Ningbo 315211, China. pinoav@hotmail.com
Xu
Shujun
S
Zhao
Kai
K
Xiao
Bingxiu
B
Guo
Junming
J
D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D002118:Calcium / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D002463:Cell Membrane Permeability / Q000187:drug effects* / Q000502:physiology; D003600:Cytosol / Q000378:metabolism; D004533:Egtazic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D005260:Female; D006367:HeLa Cells; D006801:Humans; D045022:Lactate Dehydrogenases / Q000378:metabolism; D008870:Microtubules / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure*; D054789:Ribosome Inactivating Proteins, Type 1 / Q000494:pharmacology; D015978:Trichosanthin / Q000378:metabolism / Q000494:pharmacology*; D014404:Tubulin / Q000378:metabolism; D002583:Uterine Cervical Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology
D000972:Antineoplastic Agents, Phytogenic; D054789:Ribosome Inactivating Proteins, Type 1; D014404:Tubulin; D004533:Egtazic Acid; D015978:Trichosanthin; C046770:EGTA acetoxymethyl ester; D045022:Lactate Dehydrogenases; D002118:Calcium