PDCD1 and breast carcinoma: Initial cancer immunotherapy trials have been majorly performed by using some antibodies such as ipilimumab (CTLA-4 targeting antibody), anti-programmed cell death 1 (anti-PD-1), anti-programmed death-ligand 1 (anti-PD-L1), and anti 4-1BB [11], alongside with the administration of cancer vaccines like trastuzumab emtansine for advanced her2+ breast cancer [12], NCS-DNA E7 vaccine against cervical cancer [13], and atezolizumab for non-small cell lung cancer [14].