MECP2 and Rett syndrome: MeCP2, a key epigenetic regulator, regulates chromatin organization, gene transcription and gene promoters by binding to methylated DNA.16, 17, 18, 19 It is a master regulator of gene expression and is a genetic cause of a variety of neurological disorders, such as Rett syndrome, and its role in neuronal systems has been well studied.20 Recently, MeCP2 is reported to participate in cell growth and tumorigenesis.21, 22 However, its role in many types of cancer, including GC, has not been well studied, and particularly the molecular mechanisms underlying its action remain unknown.