Remarkably, the specific upregulation of miR-21 dependent in p53-deficient metastatic tumor cells, which appears to be mediated by increased mTOR and Stat3 activity (143), was also found in human metastatic lung tumors bearing mutated p53 gene (143), thus supporting a potential mechanism of metastatic spreading in human tumors. The gene discussed is TP53; the disease is neoplasm.