CTCF (CCCTC-binding factor) is an essential protein encoded by the gene of the same name, which is ubiquitously expressed and plays an important role in the regulation of gene expression; the multiple activities of CTCF in mammalians include transcriptional activation and repression, gene silencing, constitutive chromatin insulation, and functional reading of imprinted states, reasons for which it has been named the master weaver of the genome [8]. CTCF has been proposed as a novel tumor suppressor gene because the CTCF expression suppresses tumor cell proliferation [9]. The gene discussed is CTCF; the disease is neoplasm.