Forskolin: A potential antimetastatic agent

Abstract

Forskolin, a diterpene from the roots of an Indian plant, Coleus forskohlii, is a potent platelet aggregation inhibitor and has been examined for its effects on (a) tumor-induced human platelet aggregation and (b) pulmonary tumor colonization in mice. These studies employed a subline of B16 murine melanoma, BI6-FIO (highly meta-static to lungs). Forskolin (2 μM) strongly inhibits the melanoma cell-induced human platelet aggregation. A single dose of forskolin (82 μg/mouse) administered in- traperitoneally 30 or 60 min prior to tail vein injection of cultured BI6-FIO cells (2 or 3 × 10s cells/mouse) reduced tumor colonization in the lungs by more than 70%. Similar results were obtained in three separate experiments. These findings raise the possibility that forskolin could prove of value in the clinic for the prevention of cancer metastasis.