title: Increase in cytosolic calcium maintains plasma membrane integrity through the formation of microtubule ring structure in apoptotic cervical cancer cells induced by trichosanthin.
abstract: 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.
authors.affiliation: Medical School, Ningbo University, Ningbo 315211, China. pinoav@hotmail.com
authors.forename: Ping
authors.initials: P
authors.lastname: Wang
authors.forename: Shujun
authors.initials: S
authors.lastname: Xu
authors.forename: Kai
authors.initials: K
authors.lastname: Zhao
authors.forename: Bingxiu
authors.initials: B
authors.lastname: Xiao
authors.forename: Junming
authors.initials: J
authors.lastname: Guo
mesh_terms: 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
chemical_list: 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