Initial studies identified several hypermethylated genes (e.g., homeobox protein Hox-A9, HOXA9; RASSF1A and CASP8), which are associated with tumor suppression, differentiation, and apoptosis, and defined a CIMP methylator phenotype marked by the extensive methylation of multiple CpG islands linked to poor prognosis [138,139,140]. Here, HOXA9 is linked to neoplasm.