Role of green tea catechins in modulating stromal-epithelial interaction in prostate cells

Abstract

Recent years have witnessed a significant interest in phytonutrients as treatment module for a range of diseases, including cancers. Catechins, predominant in green tea are potent antioxidants belonging to the flavonoid family that have been linked epidemiologically to a lower prevalence of prostate pathologies in Asian nations. In the present work, we investigated ameliorative potential of green tea catechins (epigallocatechin, EGC, and epigallocatechin 3-gallate, EGCG) on the aberrant proliferation of normal prostate epithelial cells driven by paracrine action of stromal medium, conditioned with estradiol (E₂) and dihydrotestosterone (DHT) (20 pM and 10 nM respectively). It was observed that EGC (5 µM) significantly inhibited the aberrant epithelial proliferation induced by stromal conditioned medium (CM), with a decreased expression of ERα, ERβ, AR, CK05, CK18, and PSA. Further, the CM collected after pre-treatment of stromal cells with EGCG (0.75 µM), had an inhibitory effect on epithelial cell proliferation, with reduction in the expression of ERα, AR, and CK05 while the expression of ERβ, CK18, and PSA were increased. These findings suggest that EGC helps in downregulating the aberrant epithelial proliferation while EGCG is able to downregulate the proliferative potential of stromal cell secretome. These insights will help in deciphering preventive measures against prostate pathologies involving stromal-epithelial cross-talk.