As a tumor suppressor, miR-34a is down-regulated for example in glioblastoma, meningioma, lung carcinoma, prostate carcinoma and colon cancer, targeting Delta-like protein1 (DLL1), jun proto-oncogene (JUN), MET proto-oncogene (MET), CD44 molecule (CD44) and Notch-1 [35–39]. The gene discussed is JUN; the disease is lung carcinoma.