Multifaceted Evaluation of Isoflavone-Rich Fabaceae Species in Prostate Cancer In Vitro Models

Dietary factors, including the consumption of isoflavones-rich foods of plant origin, may contribute to the reduced incidence of prostate cancer. Isoflavones, natural phytoestrogens often found in legumes, can modulate estrogen and androgen receptor signaling. This study aimed to evaluate the biological potential of isoflavone-rich extracts obtained from twelve species from the Fabaceae family, targeting prostate cancer cell viability, proliferation, inflammatory markers, prostate-specific antigen secretion, and 5α-reductase activity. The tested extracts showed moderate cytotoxic activity against prostate cancer cell lines, apart from highly susceptible PC3 cells, and only weak toxicity to normal prostate epithelial cells. Significant antiproliferative activity was observed, especially for Cytisus scoparius, Ononis arvensis, and Genista tinctoria, while most extracts reduced prostate-specific antigen (PSA) secretion in normal prostate cells. Furthermore, the extracts showed anti-inflammatory properties by reducing the pro-inflammatory cytokine interleukin 6 (IL-6) and improving cytokine balance indices. Multivariate analyses revealed correlations between total isoflavone content and antiproliferative activity.