PTGS2 and neoplasm: It was found that BCR, C4B, DAB2IP, MEST, RARA, SEPT5, TFF1, THY1 and SERPINA5 were all hypermethylated in hormone receptor negative, basal-like, and/or TP53 mutated tumours, whereas FABP3, FGF2, FZD9, GAS7, HDAC9, HOXA11, MME, PAX6, POMC, PTGS2, RASSF1, RBP1 and SCGB3A1 were hypermethylated in hormone receptor positive, luminal A and/or p53 wild-type tumours.