The correlation between ARF and SLUG in human prostate cancer. (A) Levels of ARF and SLUG expression among normal, stages II and IV of prostate cancer. **, p < 0.01 and *, p < 0.05 indicate the statistical significance by Student's t‐test. (B) Statistical analysis of the correlations between ARF and SLUG, in human prostate cancer specimens. (C) IHC staining of ARF and SLUG in human prostate cancer tissues. Bars equal 50 μm. (D) The signaling network of ARF, SLUG, SUMO1 and E‐cadherin for prostate cancer progression.