Moreover, it has been reported that the over-expression of miR-21 is able to mediate cell survival and proliferation by targeting several potential tumor suppressor genes, like phosphatase and tensin homolog (PTEN) [177], tropomyosin 1 (TPM1) [178] and programmed cell death 4 (PDCD4) [179]. The gene discussed is PTEN; the disease is neoplasm.