For example, the expression level of miR-29s was found to be inversely correlated with DNA methyltransferase 3A (DNMT3A) and DNA methyltransferase 3B (DNMT3B) in lung cancer tissues by controlling methylation to inhibit the reexpression of tumor suppressor genes and inhibit tumorigenesis [45]. This evidence concerns the gene DNMT3A and lung carcinoma.