Protective effect of (±)-gossypol through modulation of VEGF and apoptosis in mice bearing Ehrlich’s solid carcinoma

This study aimed to demonstrate the protective effect of the racemic form of gossypol ((±)-gossypol) on Ehrlich's solid carcinoma (ESC) model as a syngeneic breast cancer model. In the study, solid tumors developed in 100 % of BALB/c mice in the tumor control group, no tumor development was observed in the group treated with (±)-gossypol prior to tumor cell implantation, and tumor formation was determined as 28.6 % in the post-implantation gossypol treatment group. (±)-Gossypol treatment significantly reduced VEGF expression, indicating a potent anti-angiogenic effect. In the tumor control group, VEGF expression was observed to be markedly intense and extensively distributed across the tumor tissue. Conversely, in the post-implantation gossypol treatment group, VEGF expression was assessed to be significantly lower in comparison to the tumor control group. Administration of (±)-gossypol (40 mg/kg/day ip) for five consecutive days was well tolerated, with no observable signs of systemic toxicity, such as >5 % weight loss or behavioral abnormalities on mice. These findings revealed that (±)-gossypol, in addition to its tumor suppressive effect, can inhibit pro-angiogenic effects of Ehrlich's ascites carcinoma (EAC) cells and have a protective effect in breast cancer.