PDCD4 and colorectal cancer: Interestingly, the SLUG mRNA levels in colorectal cancer tissues and normal tissues were similar (Figure 2A) and no correlation between PDCD4 and SLUG mRNA level was found [Spearman's correlation coefficient = 0.0159, 95% confidence interval = (−0.081, 0.115), p = 0.728] (Figure 2B).