DNMT3A and colorectal carcinoma: Our results indicated that DNMT3b was involved in the specific methylation of SLC5A7, because SLC5A7 mRNA and protein expression was upregulated followed by silencing of DNMT3b (Fig. 1C, D), whereas silencing of DNMT1 and DNMT3a expression had no significant effect on SLC5A7 expression in CRC cells (Fig. 1C, D).