Increased formation of phospho-H2AX observed in human lung carcinoma cells exposed to ionizing radiation [81] and decreased levels of phospho-H2AX with increased expression of DNMT1 by histone deacetylase (HDAC) inhibitors [82, 83] further support our results in malignantly transformed renal epithelial cells. This evidence concerns the gene DNMT1 and lung carcinoma.