Immune Checkpoints in Colorectal Cancer

Colorectal cancer (CRC) ranked the first in cancer incidence in Hong Kong and it is frequently lethal with heterogeneous drug responses and survival outcomes. Immune-based approaches targeting to enhance tumor-specific responses have been actively under investigation as therapeutic strategies. Currently, PD1 and PD-L1 blockade has shown promising results in clinical trials especially in colorectal cancer patients with microsatellite instability. This study aims to examine the role of PD-L1/PD1 in immune cell-mediated cytotoxicity in colorectal cancer patients.