The inverse correlation between miR-133b and CXCR4 in CRC cells and clinical samples. (A) CXCR4 protein expression in CRC cells was detected using Western blot analysis normalized to GAPDH expression. Expression of miR-133b and the CXCR4 protein level was inversely correlated. (B) The inverse correlation between miR-133b and CXCR4 in CRC tissues. miR-133b and CXCR4 mRNA were measured using qRT-PCR. Correlation analysis showed a significant relationship between these factors (Spearman r = -0.2840; P = 0.0456).