Anti-cancer effects of torulene, isolated from Sporidiobolus pararoseus, on human prostate cancer LNCaP and PC-3 cells via a mitochondrial signal pathway and the down-regulation of AR expression

Abstract

In this work, we investigated the anti-cancer effect of torulene, a carotenoid from Sporidiobolus pararoseus, on androgen-sensitive/insensitive prostate cancer cells lines and found that torulene induced apoptosis at moderate cytotoxic concentrations in both cell lines. It was further demonstrated that the apoptosis induced by torulene was due to the modulation of Bcl-2 family members, resulting in decrease of mitochondria membrane potential and increase of the intracellular calcium concentration. Furthermore, its growth-inhibitory effects on LNCaP cells also showed a relationship with the down-regulation of AR and PSA expression. Therefore, the results indicated that a mitochondria-mediated pathway and the expression of AR might play essential roles in the apoptosis process induced by torulene in prostate cancer cells.