Supernatant of bacterial fermented soybean induces apoptosis of human hepatocellular carcinoma Hep 3B cells via activation of caspase 8 and mitochondria.
SC-1, the aqueous phase of soybean fermentation products by bacteria (Bacillus subtilis and Bacillus brevis), significantly inhibited the growth and clonogenesity of human hepatocellular (Hep 3B), mouse hepatocellular (ML-1), and human colorectal (HCT 116 and HT-29) carcinoma cells. Cytotoxicity of SC-1 in Hep 3B cells was through the process of apoptosis characterizing by increase in cell population of sub-G(1) phase, fragmentation of DNA, and change of nuclear morphology. Treatment of Hep 3B cells with SC-1 activated caspase 8 and caspase 3. Elevation of nuclear DNA fragmentation factor 40 (DFF40) and cleavage form of poly(ADP-ribose) polymerase (PARP) were also observed. SC-1 also activated intrinsic pathway via increase of pro-apoptotic (tBid, Bak and Bax) and decrease of anti-apoptotic (Bcl-2 and Bcl-x(L)) proteins on mitochondria, disruption of mitochondrial membrane potential, release of cytochrome c and Smac (second mitochondria-derived activator of caspase/direct IAP binding protein with low PI) from mitochondria, and activation of caspase 9. Inhibition on protein expression of Ku70 in cytosol and cyclooxygenase (COX)-2, but not COX-1, in whole cell lystes were revealed in SC-1-treated Hep 3B cells. These results suggest caspase 8, Ku70 and mitochondria are involved in the antitumor mechanism of SC-1 in Hep 3B cells.
Su
Chun-Li
CL
Department of Nursing, Chang Jung Christian University, Tainan 711, Taiwan, ROC.
Wu
Chao-Jung
CJ
Chen
Fang-Nan
FN
Wang
Be-Jen
BJ
Sheu
Shane-Rong
SR
Won
Shen-Jeu
SJ
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D001407:Bacillus / Q000378:metabolism*; D001412:Bacillus subtilis / Q000378:metabolism; D006528:Carcinoma, Hepatocellular / Q000473:pathology; D053181:Caspase 8 / Q000187:drug effects / Q000378:metabolism*; D045744:Cell Line, Tumor; D051546:Cyclooxygenase 2 / Q000378:metabolism; D053938:DNA Fragmentation; D004789:Enzyme Activation; D005285:Fermentation; D016193:G1 Phase / Q000187:drug effects; D045325:HCT116 Cells; D019073:HT29 Cells; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology; D051379:Mice; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism*; D024101:Mitochondrial Proteins / Q000378:metabolism; D013025:Glycine max / Q000737:chemistry*
D024101:Mitochondrial Proteins; D051546:Cyclooxygenase 2; D053181:Caspase 8