RAP1B and colonic neoplasm: Of note, a single miRNA can regulate a multitude of target genes concomitantly; for instance, it has been reported that miR-139-5p suppresses progression of liver cancer by down-regulating Rho-kinase 2 [21]; and miR-139-5p could repress the activity of RAP1B [37] and IGF-IR [17] in colon cancer.