The Effect of Croton lechleri on Prostate Cancer Progression

Abstract

Prostate cancer (CaP) continues to be the second leading cause of cancer deaths in men in the US (Siegel 2014). Many of the cancer drugs currently on the market are from or are structurally similar to compounds found in natural plant products. We investigated the effect of a tree bark native to the Peruvian Amazon, Croton lechleri on the proliferation and invasion of two prostate cancer cell lines, DU‐145 and PC‐3. C. lechleri is commonly used by Peruvian healers to treat prostate conditions and is one of the most popular treatments purchased from herbal markets (Bussmann 2007). C. lechleri has antioxidant capabilities as a free radical scavenger (DeMarino 2008) and species in the same genus as C. lechleri decrease cell adhesion and induce apoptosis in stomach and colon cancer cell lines (Sandoval 2002). We used C. lechleri latex extracts, the form used by Peruvian Shaman for therapeutic use, to treat PC‐3 and DU‐145 CaP cell lines and evaluate their ability to proliferate using CellTiter 96® and invade using a modified Boyden Chamber. C. lechleri, at concentrations equal to and less than those used as Peruvian therapeutic treatments, significantly reduced proliferation of both PC‐3 and DU‐145 cells in a dose dependent manner. C. lechleri reduced invasion of DU‐145 cells but not the more invasive PC‐3 cells. Studies of the effect of C. lechleri on cancer progression have been contradictory, depending on the type of cancer under investigation. Here, we describe that in prostate cancer, C. lechleri decreases both the ability of prostate tumor cells to proliferate and invade. We are currently investigating the effect of C. lechleri on CaP cell apoptosis.This project was funded NIH‐INBRE Grant from the National Center for Research Resources and Winthrop University Research Council