The down-regulation of miR-373 enhanced lung cancer cells' radio-sensitivity and inhibited migration and invasion by targeting tissue inhibitor of metalloproteinases 2 (TIMP2) and regulating the phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) and drosophila mothers against decapentaplegic protein (Smad) pathways (11). The gene discussed is TIMP2; the disease is lung carcinoma.