PTEN and malignant colon neoplasm: Accumulating evidence has indicated that a number of miRNAs are capable of regulating tumor metastasis by modulating the expression of certain genes involved in signaling networks, including phosphatase and tensin homolog (PTEN)/phosphatidylinositol-3-kinase (PI3K), EGF receptor (EGFR), TGFβ, and p53 pathways in colon cancers (Figure 1) (Table 2) [37].