In Vitro Assessment of Diet-Derived Phytochemicals on PSA Secretion

Abstract

Prostate cancer (PCa) is increasingly a global public health burden. The prostate specific antigen (PSA) is the major biomarker for diagnosing and managing PCa. Due to the importance of PSA as a biomarker and as a downstream product of the androgen receptor (AR), it was imperative to expose LNCaP cells to selective diet-derived phytochemicals and investigate the effect on PSA protein secretion. The phytochemicals: Curcumin, 3,3’-Diindolylmethane (DIM) and Epigallcatechin-3-gallate (EGCG) were utilised singly and in paired combinations as in vitro treatments. The ELISA technique was utilised to assess secreted PSA levels. Results obtained indicated that DIM posed inhibitory effects to PSA production and secretion. Uniquely, DIM lowered PSA levels significantly when compared to curcumin and EGCG. This finding corroborates with previous reports where DIM was observed to inhibit AR protein expression. It is suggestive that DIM targets the androgen receptor and its downstream pathway that produces PSA. In conclusion, DIM may hold overwhelming potential chemoprevention and management of PCa, and can be harnessed for enhanced clinical applications.