miR-203 enhances cytotoxicity of cisplatin on 5637 and T24 bladder cancer cells.

<p>(A) miR-203 expression levels in 5637 and T24 cells transfected with miR-203 mimics/negative control. miR-203 levels were significantly increased in cells transfected with miR-203 mimics compared with cells transfected with negative control (*<i>P</i><0.001, t test, n = 6). (B, C) Concentration-dependent curves for 5637 and T24 cell lines transfected with miR-203 mimics and negative control at 24h. Cell viabilities of miR-203-overexpressing cells were dramatically reduced when compared with negative control cells at 5, 10, 15, 20, 25 and 30μM cisplatin (all at <i>P</i><0.05, t test). (D) Flow cytometry analysis for apoptosis via double staining of cells with Annexin V FITC and propidium iodide (PI). (E) Quantification analysis of apoptosis shown in Fig 2B. Overexpression of miR-203 significantly augmented apoptosis in 5637 and T24 cell lines (*<i>P</i><0.01, t test, n = 6). (F) TUNEL assay indicated 5637 and T24 cell lines transfected with miR-203 mimics showed elevated levels of DNA cleavage compared with normal control (40×). Cells were stained with DAPI and subjected to TUNEL assay to detect DNA and apoptotic cells.