PDCD1 and colorectal carcinoma: Indeed, colorectal carcinoma patients with MSI-high status showed a high response rate to PD-1/PD-L1 immunotherapy and a good survival rate, suggesting that a higher mutational burden may result in the formation of more tumor antigens (neoantigens) to trigger a robust anti-tumor immune response and to upregulate tumor CD274 expression41,42.