Results demonstrated a significant (p < 0.05) reduction in the extent of methylation of LINE-1 repetitive elements, chosen as a surrogate of the overall genomic DNA methylation, and in the levels of specific promoter methylation of cancer testis genes (i.e., MAGE-A1 and NY-ESO-1) by guadecitabine treatment (Suppl. Here, MAGEA1 is linked to cancer.