PDCD4 and Familial prostate cancer: Transforming growth factor, beta receptor 2 (TGFBR2), Programmed cell death protein 4 (PDCD4), Reversion-inducing cysteine-rich protein with kazal motifs (RECK), p57kip2 and Phosphatase and Tensin Homolog Deleted from Chromosome 10 (PTEN) have been reported as miR-21 targets in prostate cancer [56,57,58,59,60].