miR-99a is significantly down-regulated in bladder cancer cell lines and in bladder cancer tissues. (A) The expression level of miR-99a in two immortalized human bladder epithelium cells (HCV29 and HU609) and five bladder cancer cell lines (J82, HT1376, RT4, T24 and TCCSUP). Data are shown as mean ± s.d. (n = 3); **indicates P-value < 0.01; ***indicates P-value < 0.001. (B) HE staining of the bladder cancer (C) tissue and adjacent non-neoplastic tissues (N) of 2 patients with bladder cancer. (C) The relative expression of miR-99a in 100 pairs of bladder cancer (C) and adjacent non-neoplastic tissues (N). (D) Normalized expression of miR-99a in 100 pairs of bladder cancer and adjacent normal tissues.