Background: The expression level of some microRNAs (miRNAs) in lung cancer has been associated with an increased risk of cancer. miRNAs play a substantial role in the pathogenesis of human cancers. Because of that, miRNA polymorphisms can be important for carcinogenesis. MiR-34 is a family of miRNAs known to have reduced levels of expression in lung cancer and other human cancers (pancreas, colon). It functions like tumor suppressor and targets oncogenes like MET, RET, and RAB43. Also miR-125 family is related with many cancer types and targets P53, BCL2, VEGF, and EGFR.
