HAVCR2 and neoplasm: In colorectal cancer, particularly microsatellite-stable (MSS) tumours that often fail to respond to conventional checkpoint inhibitors, T-cell immunoglobulin and mucin-domain containing-3 (TIM-3), lymphocyte activation gene-3 (LAG-3), and T-cell immunoreceptor with Ig and ITIM domains (TIGIT) have gained attention as novel inhibitory receptors.