MLH1 and thymic epithelial neoplasm: Their results were in accordance with Chen and coworkers, who found that tumor suppressor genes and DNA repair genes, including hMLH1, RASSF1A, MGMT, p16/INK4, DAPK, FHIT, RAR2, CDH1, and APC, are frequently hypermethylated in thymic epithelial tumours, all found to be methylated in almost 20 to 40% of the cases [13,30].