Bee venom induces apoptosis through intracellular Ca2+ -modulated intrinsic death pathway in human bladder cancer cells - Abstract

OBJECTIVES: To focus on bee venom-induced apoptosis in human bladder cancer TSGH-8301 cells and to investigate its signaling pathway to ascertain whether intracellular calcium iron (Ca(2+)) is involved in this effect.

METHODS: Bee venom-induced cytotoxic effects, productions of reactive oxygen species and Ca(2+) and the level of mitochondrial membrane potential (ΔΨm) were analyzed by flow cytometry. Apoptosis-associated proteins were examined by Western blot analysis and confocal laser microscopy.

RESULTS: Bee venom-induced cell morphological changes and decreased cell viability through the induction of apoptosis in TSGH-8301 cell were found. Bee venom promoted the protein levels of Bax, caspase-9, caspase-3 and endonuclease G. The enhancements of endoplasmic reticulum stress-related protein levels were shown in bee venom-provoked apoptosis of TSGH-8301 cells. Bee venom promoted the activities of caspase-3, caspase-8, and caspase-9, increased Ca(2+) release and decreased the level of ΔΨm. Co-localization of immunofluorescence analysis showed the releases of endonuclease G and apoptosis-inducing factor trafficking to nuclei for bee venom-mediated apoptosis. The images revealed evidence of nuclear condensation and formation of apoptotic bodies by 4',6-diamidino-2-phenylindole staining and DNA gel electrophoresis showed the DNA fragmentation in TSGH-8301 cells.

CONCLUSIONS: Bee venom treatment induces both caspase-dependent and caspase-independent apoptotic death through intracellular Ca(2+) -modulated intrinsic death pathway in TSGH-8301 cells.

Written by:
Ip SW, Chu YL, Yu CS, Chen PY, Ho HC, Yang JS, Huang HY, Chueh FS, Lai TY, Chung JG.   Are you the author?
Department of Nutrition, China Medical, Taipei, Taiwan.

Reference: Int J Urol. 2012 Jan;19(1):61-70.
doi: 10.1111/j.1442-2042.2011.02876.x. Epub 2011 Dec 11.

PubMed Abstract
PMID: 22151644

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