PTGS2 and colorectal carcinoma: Among the 5 CRC cell lines of GSE32323 SULT1A1 in Colo32 cells, PTGS2 in HCT-116 cells, ALDH1A3 and SOCS3 in HT-29 cells and ALDH1A3 and TIMP1 in SW480 cells showed remarkable upregulation after demethylation treatment (Fig. 2, Additional file 4: Table S3).