A method of treating prostate cancer by administering a pharmaceutically-acceptable amount of a crude extract of the indigenous Jamaican plant Ball Moss (Tillandsia Recurvata) comprising one or more cycloartane isolates, and the isolates used in the method for eliciting thereby a kinase inhibitory response of prostate cancer cells by selectively inhibiting MRCKα kinase and angiogenesis of (growth of new blood vessels) to reduce the viability of prostate cancer cells. The method and compounds holds promise as a chemopreventive agent, without causing excessive damage to normal cells.
