Although ICIs including ipilimumab (targets CTLA-4), nivolumab (targets PD-1), and atezolizumab (targets PD-L1) are also approved for CRC by the Food and Drug Administration, due to their limitations such as poor efficiency and drug resistance in CRC treatment, it is also of great importance to study on new immune checkpoint and inhibitors (Franke et al., 2019; Sclafani, 2019). Here, CTLA4 is linked to colorectal carcinoma.