Cucurbitacin E is an important member of the cucurbitacin family and exhibits inhibitory effects in various types of cancer. Cucurbitacin is a potential antineoplastic drug; however, its anticancer effect in human prostate cancer (PC) remains unknown. The aim of the present study was to determine whether the effect of cucurbitacin E on the cell viability and apoptosis of the human PC cell line, LNCaP, was mediated by cofilin-1- and mammalian target of rapamycin (mTOR). The results of the present study demonstrated that cucurbitacin E significantly exhibited cytotoxicity, suppressed cell viability (P<0.0001) and induced apoptosis (P=0.0082) in LNCaP cells. In addition, it was demonstrated that treatment with cucurbitacin E significantly induced cofilin-1 (P=0.0031), p-mTOR (P=0.0022), AMP-activated protein kinase (AMPK; P=0.0048), cellular tumor antigen p53 (p53; P=0.0018) and caspase-9 (P=0.0026) protein expression in LNCaP cells, suggesting that cucurbitacin E exerts its effects on LNCaP cells through cofilin-1, mTOR, AMPK, p53 and caspase-9 signaling. These results suggested that cucurbitacin E maybe used as a therapeutic agent in the treatment of human PC.