PAK6 and prostate cancer: To examine whether the biological effects of down-regulating miR-23a correlated with PAK6 protein levels in clinical prostate cancer tissues, PAK6 protein levels in 20 paired prostate cancer and adjacent non-tumor tissues were examined by Western blotting, and miR-23a expression was determined by real-time PCR (Supplementary Figure 1A, 1B; the same samples as in Figure 1C).