STAT3 and colorectal carcinoma: To verify the involvement of SOCS1 in suppressing JAK1‐STAT3 signaling in KOSRC‐1 CRC cells, we knocked down SOCS1 in wild‐type and KOSRC‐1 CMT93 cells and then analyzed the activity of JAK1‐STAT3 signaling and the expression of IRF1 and PD‐L1.