As shown in Fig. 6, PPI analysis showed known and predicted interactions interaction between SLC4A4 with SLC9A3, SLC26A6, ENSG00000214921, SLC26A4, DCTN1, AHCYL1, CA4, SLC9A3R1, SLC9A1, and CA2, most of which had been reported be oncogenes or tumor suppressors in cancers (including CRC)23-26. Here, CA4 is linked to cancer.