miR-449a is downregulated in PCa tissues and cell lines. (A) The expression of miR-449a was detected in PCa tissues and adjacent tissues using qRT-PCR. miR-449a was significantly downregulated in PCa tissues. ***P<0.001, paired two-tailed Student's t-test. (B) miR-449a expression level was remarkably lower in phage III-IV PCa patients compared with phage I-II. **P<0.01, unpaired two-tailed Student's t-test. (C) The expression of miR-449a was maintained at a lower level in PCa patients who were recurrent with bone metastasis in two years after surgical operation. **P<0.01, unpaired two-tailed Student's t-test. (D) The expression of miR-449a was detected in PCa cells and RWPE-1 using qRT-PCR. miR-449a was decreased in PCa cell lines. **P<0.01, ***P<0.001, unpaired two-tailed Student's t-test.