RASSF1 and medullary thyroid gland carcinoma: In spite of the fact that RASSF1A gene promoter hypermethylation is linked to more aggressive thyroid cancers, CpG island methylation of tumor-associated genes— such as p16, TSHR, MGMT, and PTEN—have not shown any significant degree of hypermethylation in MTC[73,85-87].