Upregulation of TIGIT and PD-1 in Colorectal Cancer with Mismatch-repair Deficiency

Background: The role of T cell Ig and ITIM domain (TIGIT) and programmed cell death-1 (PD-1) in colorectal cancer (CRC) with mismatch repair deficiency is unknown. Methods: This was a study of 60 CRC patients with mismatch repair deficiency and 30 healthy controls between June 2015 and October 2015. Results: The expression of Foxp3, PD-1, and TIGIT was higher in cancer tissues compared with adjacent mucosa (all P < .05). Patients with advanced TNM stage had a significantly higher expression of TIGIT (P = .025) and PD-1 (P = .020) than patients with early-stage CRC. The disease-free survival (DFS) of patients with high TIGIT (HR = 3.96, 95%CI: 1.34-11.69, P = .013) or PD-1 (HR = 214.8, 95%CI: 49.88-925.2, P < .001) expression were better. The overall survival (OS) of the patients with CRC and high expression of PD-1 was worse than those with low expression (HR = 4.01, 95%CI:1.26-12.69, P = .019). Conclusion: TIGIT and PD-1 are upregulated in CRC with mismatch repair deficiency and associated with TNM stage and DFS.

Automated summary

In colorectal cancer (CRC) with mismatch repair deficiency, TIGIT and PD-1 are upregulated and associated with TNM staging and disease-free survival (DFS). Patients with high expression of TIGIT or PD-1 had better DFS, but worse overall survival (OS) for those with high expression of PD-1.