Fish bone fermented using Monascus purpureus (FBF) has total phenols and functional amino
acids that contribute to its anti-oxidant and anti-inflammatory properties. Colorectal cancer, one of
the most prevalent cancers and the third largest cause of death worldwide, has become a serious
threat to global health. This study investigates the anti-cancer effects of FBF (1, 2.5 or 5 mg/mL)
on the cell growth and molecular mechanism of HCT-116 cells. The HCT-116 cell treatment with
2.5 or 5 mg/mL of FBF for 24 h significantly decreased cell viability (p < 0.05). The S and G2/M
phases significantly increased by 88–105% and 25–43%, respectively (p < 0.05). Additionally, FBF
increased the mRNA expression of caspase 8 (38–77%), protein expression of caspase 3 (34–94%),
poly (ADP-ribose) polymerase (PARP) (31–34%) and induced apoptosis (236–773%) of HCT-116
cells (p < 0.05). FBF also increased microtubule-associated protein 1B light chain 3 (LC3) (38–48%)
and phosphoinositide 3 kinase class III (PI3K III) (32–53%) protein expression, thereby inducing
autophagy (26–52%) of HCT-116 cells (p < 0.05). These results showed that FBF could inhibit HCT-116
cell growth by inducing S and G2/M phase arrest of the cell cycle, apoptosis and autophagy. Thus,
FBF has the potential to treat colorectal cancer.