Over-the-Counter Honeybee Remedy Slows Prostate Cancer Growth

New research on a natural remedy suggests that it may inhibit the growth of prostate cancer cells. Richard B. Jones, PhD, assistant professor in the Ben May Department for Cancer Research and Institute for Genomics and Systems Biology and colleagues tested the effect of caffeic acid phenyl ester (CAPE), a compound isolated from honeybee hive propolis, on human prostate cancer cells and a mouse model of prostate cancer. Results showed that CAPE successfully slowed the proliferation of cultured cells isolated from human prostate tumors, even when exposed to low concentrations, such as those achievable with oral administration. Furthermore, CAPE was also effective at slowing the growth of human prostate tumors grafted into mice. Six weeks of treatment with the compound decreased tumor volume growth rate by half, but when CAPE treatment was stopped, tumor growth resumed its prior rate, suggesting that CAPE stops cell division rather than killing cancerous cells. Further research revealed that CAPE suppresses the activity of proteins in the p70S6 kinase and Akt pathways, which are important sensors of sufficient nutrition that can trigger cell proliferation. “It appears that CAPE basically stops the ability of prostate cancer cells to sense that there’s nutrition available,” said Jones. “They stop all of the molecular signatures that would suggest that nutrition exists, and the cells no longer have that proliferative response to nutrition.”