Overall, we uncovered that: (1) DFE, a native Taiwanese fern and a Chinese medicine, impaired growth and progression (migration and invasion) in both LNCaP androgen-dependent cells as well as C4-2 castration-resistant cells; (2) DFE significantly diminished the mRNA and protein expression of SREBP-1, FASN, AR, and PSA in PCa cells. The gene discussed is KLK3; the disease is posterior cortical atrophy.