This range of variation in response to 5-aza has been previously described for other genes such as somatostatin in gastric cancer cell lines, GADD45A in osteosarcoma cell lines or LCR and L1 of HPV-16 in cervical cancer cell line [52]–[54].The correlation between UTF1 expression and promoter methylation was also unexpected. The gene discussed is GADD45A; the disease is osteosarcoma.