To investigate the antitumor activity and action mechanism of
fengycin using the human
lung cancer cell line 95D. The antitumor activity of
fengycin was tested in vitro and in vivo.
Reactive oxygen species production, Ca(2+) uptake, and mitochondrial membrane potential loss induced by
fengycin in 95D cells were measured by flow cytometry and a
laser confocal microscope.
Lactate dehydrogenase release and
caspase activity in
fengycin-treated 95D cells were assayed using cytotoxicity detection kits. Apoptosis triggered by
fengycin was identified by
4,6-diamidino-2-phenylindole (
DAPI) staining and flow cytometry. The effects of
fengycin on cell-cycle and apoptosis-related
proteins were evaluated by quantitative reverse-transcription PCR and western blot. Treatment with
fengycin not only significantly decreased cell proliferation in various
cancer cell lines including 95D but inhibited the growth of xenografted 95D cells in nude mice.
Fengycin also induced
reactive oxygen species production and Ca(2+) uptake, as well as
lactate dehydrogenase release and mitochondrial membrane potential loss. Further experiments showed that
fengycin could trigger apoptosis in 95D cells and cause cell-cycle arrest at the G0/G1 stage by downregulating
cyclin D1 and
cyclin-dependent kinase 4 (CDK4). While investigating
caspase activity and the expression of apoptosis-related
proteins,
fengycin was found to induce apoptosis in 95D cells through the mitochondrial pathway, evidenced by increased
caspase activity, Bax expression, and
cytochrome c release into the cytoplasm, as well as decreased Bcl-2 levels.
Fengycin can inhibit the growth of the
cancer cell line 95D by regulating the cell cycle and promoting apoptosis, suggesting that it may have potential as an anticancer treatment.