Efficacy and safety of guttiferone E in melanoma-bearing mice.

Melanoma, an aggressive and potentially fatal skin cancer, is constrained by immunosuppression, resistance, and high toxicity in its treatment. Consequently, there is an urgent need for innovative antineoplastic agents. Therefore, this study investigated the antimelanoma potential of guttiferone E (GE). In an allogeneic murine B16 melanoma model, GE was administered subcutaneously and intraperitoneally. Antitumor evaluation included tumor volume/weight measurements and histopathological and immunohistochemical analysis. Furthermore, the toxicity of the treatments was evaluated through body/organ weights, biochemical parameters, and genotoxicity. Subcutaneous administration of 20 mg/kg of GE resulted in a significant reduction in both tumor volume and weight, effectively suppressing melanoma cell proliferation as evidenced by a decrease in mitotic figures. The tumor growth inhibition rate was equivalent to 54%. This treatment upregulated cleaved caspase-3, indicating apoptosis induction. On the other hand, intraperitoneal administration of GE showed no antimelanoma effect. Remarkably, GE treatments exhibited no toxicity, evidenced by non-significant differences in body weight gain, as well as organ weight, biochemical parameters of nephrotoxicity and hepatotoxicity, and genotoxic damage. This study revealed, for the first time, the efficacy of subcutaneous administration of GE in reducing melanoma, in the absence of toxicity. Furthermore, it was observed that the apoptotic signaling pathway is involved in the antimelanoma property of GE. These findings offer valuable insights for further exploring GE's therapeutic applications in melanoma treatment.