PTEN and benign prostatic hyperplasia: Because we found a positive correlation between METTL1 protein expression and phospho-S6K in PCa samples compared to benign prostatic hyperplasia specimens (Fig. 1E), we next analysed whether METTL1 expression was correlated with PTEN expression, a negative regulator of the PI3K/AKT/mTOR pathway, which is deleted in approximately 70% of patients with advanced PCa [47].