TY - JOUR
T1 - Cellular responses to cancer chemopreventive agent D,L-sulforaphane in human prostate cancer cells are initiated by mitochondrial reactive oxygen species
AU - Xiao, Dong
AU - Powolny, Anna A.
AU - Antosiewicz, Jedrzej
AU - Hahm, Eun Ryeong
AU - Bommareddy, Ajay
AU - Zeng, Yan
AU - Desai, Dhimant
AU - Amin, Shantu
AU - Herman-Antosiewicz, Anna
AU - Singh, Shivendra V.
N1 - Funding Information:
This investigation was supported in part by the USPHS grants CA115498 and CA101753 (to S.V.S.), awarded by the National Cancer Institute, and grant 2718/P01/2007/32 (to A.H-A.), awarded by the Polish Ministry of Science and Higher Education.
PY - 2009/7
Y1 - 2009/7
N2 - Purpose: Present study was undertaken to elucidate the mechanism of cellular responses to D,L-sulforaphane (SFN), a highly promising cancer chemopreventive agent. Methods: Mitochondrial DNA deficient Rho-0 variants of LNCaP and PC-3 cells were generated by culture in the presence of ethidium bromide. Apoptosis was assessed by analysis of cytoplasmic histone-associated DNA fragmentation and activation of caspase-3. Immunoblotting was performed to determine the expression of apoptosis- and cell cycle-regulating proteins. Generation of reactive oxygen species (ROS), mitochondrial membrane potential (MMP), and cell cycle distribution were measured by flow cytometry. Results: The Rho-0 variants of LNCaP and PC-3 cells were significantly more resistant to SFN-induced ROS generation, apoptotic DNA fragmentation, disruption of MMP, cytosolic release of cytochrome c, and G2/M phase cell cycle arrest compared with corresponding wild-type cells. SFN-induced autophagy, which serves to protect against apoptotic cell death in PC-3 and LNCaP cells, was also partially but markedly suppressed in Rho-0 variants compared with wild-type cells. SFN statistically significantly inhibited activities of mitochondrial respiratory chain enzymes in LNCaP and PC-3 cells. Conclusion: These results indicate, for the first time, that mitochondria-derived ROS serve to initiate diverse cellular responses to SFN exposure in human prostate cancer cells.
AB - Purpose: Present study was undertaken to elucidate the mechanism of cellular responses to D,L-sulforaphane (SFN), a highly promising cancer chemopreventive agent. Methods: Mitochondrial DNA deficient Rho-0 variants of LNCaP and PC-3 cells were generated by culture in the presence of ethidium bromide. Apoptosis was assessed by analysis of cytoplasmic histone-associated DNA fragmentation and activation of caspase-3. Immunoblotting was performed to determine the expression of apoptosis- and cell cycle-regulating proteins. Generation of reactive oxygen species (ROS), mitochondrial membrane potential (MMP), and cell cycle distribution were measured by flow cytometry. Results: The Rho-0 variants of LNCaP and PC-3 cells were significantly more resistant to SFN-induced ROS generation, apoptotic DNA fragmentation, disruption of MMP, cytosolic release of cytochrome c, and G2/M phase cell cycle arrest compared with corresponding wild-type cells. SFN-induced autophagy, which serves to protect against apoptotic cell death in PC-3 and LNCaP cells, was also partially but markedly suppressed in Rho-0 variants compared with wild-type cells. SFN statistically significantly inhibited activities of mitochondrial respiratory chain enzymes in LNCaP and PC-3 cells. Conclusion: These results indicate, for the first time, that mitochondria-derived ROS serve to initiate diverse cellular responses to SFN exposure in human prostate cancer cells.
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U2 - 10.1007/s11095-009-9883-5
DO - 10.1007/s11095-009-9883-5
M3 - Article
C2 - 19384467
AN - SCOPUS:67349224358
VL - 26
SP - 1729
EP - 1738
JO - Pharmaceutical Research
JF - Pharmaceutical Research
SN - 0724-8741
IS - 7
ER -