ABCC4 and colorectal carcinoma: As shown in Figure 1(A) and Supplementary Figure S1, bioinformatics analysis demonstrated that the tumor tissue levels of ABC transporters, including ABCB1, ABCB7, ABCC1, ABCC2, ABCC3, ABCC4, ABCC6, ABCC10, ABCC11, and ABCG1, were significantly higher than those in normal tissues, suggesting the MDR of CRC cells.