CYP1B1 and neoplasm: Consistent with the literature, eight loci (MTHFR, OPCML, TNFRSF25, TCF21, SFRP2, SFRP1, CYP1B1, GPIBB, DLEC and ONECUT2) [17,24,30-39] are hypermethylated in tumor tissue in our study.