MUC12 promoted RCC cell growth. A, MUC12 expression levels in different RCC cell lines. GAPDH was used as loading control. B, Knockdown efficiency of MUC12 in 786‐O cells. GAPDH served as internal control. C, Confirmation of overexpressed MUC12 in A498 cells. GAPDH was internal control. D, MTT assay showed that knockdown of MUC12 remarkably suppressed cell growth of 786‐O cells. E. MTT assay revealed that MUC12 induction increased cell growth of A498 cells. F‐G. MUC12 depletion by shRNAs decreased colony‐forming ability of 786‐O cells. F, representative images of colonies. G, statistical analysis of F. H‐I, Overexpression of MUC12 increased colony‐forming ability of A498 cells. H, representative images of colonies. I, statistical analysis of H. J, The gross of tumours in shMUC12 and control groups. K, Analysis of tumour weight of xenograft tumours. *P < 0.05; **P < 0.01