title: Autophagy is the dominant type of programmed cell death in breast cancer MCF-7 cells exposed to AGS 115 and EFDAC, new sesquiterpene analogs of paclitaxel.
abstract: The molecular mechanism of cell death induced by AGS 115 and EFDAC, sesquiterpene analogs of paclitaxel, was investigated in human breast cancer MCF-7 cells. The study was carried out using laser scanning cytometry, homeostatic confocal microscopy, atomic force microscopy and electron microscopy. AGS 115 and EFDAC exhibited a microtubule-stabilizing effect as confirmed by a significant increase in alpha-tubulin aggregation. Both paclitaxel analogs also induced death in MCF-7 cells. Evaluation of biochemical and morphological features suggested that the major form of programmed cell death induced by AGS 115 and EFDAC was autophagy. This was confirmed by MAP I LC3 expression and the ultrastructural pattern revealed by electron microscopy. Surface images of cells undergoing autophagy showed that, unlike during apoptosis, the dimensions remained unchanged, but the surface of the cell was deformed. The occurrence of apoptosis was confirmed by the efflux of Smac/DIABLO from mitochondria, caspase-7 activation and DNA loss, and did not exceed 9.7%. Therefore, AGS 115 and EFDAC appear to be promising candidates for further investigation in anti-cancer therapy.
authors: Department of Physiological Sciences, Faculty of Veterinary Medicine, Warsaw Agricultural University, Warsaw, Poland.
authors: Magdalena
authors: M
authors: Górka
authors: Włodzimierz M
authors: WM
authors: Daniewski
authors: Barbara
authors: B
authors: Gajkowska
authors: Elzbieta
authors: E
authors: Lusakowska
authors: Michał M
authors: MM
authors: Godlewski
authors: Tomasz
authors: T
authors: Motyl
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis; D001343:Autophagy; D001943:Breast Neoplasms; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D017239:Paclitaxel / Q000031:analogs & derivatives* / Q000494:pharmacology*; D012717:Sesquiterpenes / Q000494:pharmacology*; D014404:Tubulin / Q000378:metabolism
chemical_list: C508481:6,6,8-trimethyl-4,4a,5,6,7,7a,8,9-octahydrocyclopenta(4,5)cyclohepta(1,2-c)-furan-4,8-diol 4-(N-acetyl-3-phenylisoserinate); C508480:6,6,8-trimethyl-4,4a,5,6,7,7a,8,9-octahydrocyclopenta(4,5)cyclohepta(1,2-c)-furan-4,8-diol 4-(N-tert-butoxycarbonyl-3-phenylisoserinate); D000970:Antineoplastic Agents; D012717:Sesquiterpenes; D014404:Tubulin; D017239:Paclitaxel