Oleanolic Acid Suppressed DMBA-Induced Liver Carcinogenesis through Induction of Mitochondrial-Mediated Apoptosis and Autophagy

Phytochemicals appeared as a rich source of efficient and safe agents against many diseases like cancer. Various herbal sources are rich in oleanolic acid (OA). The scope of this study was to assess the biochemical and molecular mechanisms implicated in the ameliorative potency of OA against DMBA-induced liver carcinogenesis. Forty-eight male albino mice were assigned randomly to five groups (eight mice each) as follows: control healthy group, olive oil group, OA group, DMBA group, and DMBA with OA. Apoptosis, autophagy, inflammation, proliferation, and angiogenesis were investigated in the tissue samples. Histopathological examination was carried out as well as liver enzymes activity and other hepatic antioxidant and inflammatory biomarkers. The treatment with OA effectively suppressed the DMBA-initiated liver carcinogenesis via modulation of antioxidant status, induction of apoptosis and autophagy through modulating the expression of Caspase-3, Bcl-2 and Beclin-1, inhibiting angiogenesis (VEGF), proliferation (PCNA), and improved liver function and histological picture with a reduction in AFP level. Additionally, OA applies its antitumor effects by inhibition of proinflammatory transcription factor NF-κB and inflammatory markers (TNF-α and Cox-2) associated with DMBA administration. The present study shows that OA treatment efficiently suppressed the DMBA-initiated liver carcinogenesis through induction of mitochondrial-mediated apoptosis and autophagy and modulating inflammation.