In addition, the viability of AP4-proficient CRC cells was significantly lower when MDC1 was silenced by specific siRNAs (Fig. 7D and Fig. S5D), whereas ectopic MDC1 expression increased the viability of AP4-deficient CRC cells (Fig. 7E and Fig. S5E). The gene discussed is TFAP4; the disease is colorectal carcinoma.