Prognostic relevance of programmed cell death 1 ligand 2 (PDCD1LG2/PD-L2) in patients with advanced stage colon carcinoma treated with chemotherapy

Sci Rep. 2020 Dec 18;10(1):22330. doi: 10.1038/s41598-020-79419-3.

Abstract

Colorectal cancer (CRC) is the leading cause of cancer-related mortality worldwide. Although the role of tumor programmed cell death 1 ligand 1 (PD-L1) in suppressing antitumor immunity has been validated in various malignances, the impact of PD-L2 (PD-L2/PDCD1LG2) within tumors remains elusive. Here, we examined tumor PD-L2 expression by immunohistochemical analysis and assessed its association with clinicopathological characteristics and the infiltration of intratumoral T lymphocytes in colon carcinoma patients (n = 1264). We found that tumor PD-L2 status was correlated with perineural invasion (PNI) and associated with survival outcome in colon carcinoma patients. The level of tumor PD-L2 was positively associated with tumor PD-L1 expression but inversely associated with the density of CD8+ tumor-infiltrating lymphocytes (TILs). Patients with elevated tumor PD-L2 levels had a favorable 5-year overall survival (OS) compared to patients with low PD-L2 levels (57% vs 40%, p < 0.001), especially in advanced stage colon carcinoma patients. Low tumor PD-L2 expression was associated with an increased 5-year OS risk among advanced stage colon carcinoma patients by univariate analysis [hazard ratio (HR) = 1.69, 95% CI 1.324-2.161, p < 0.001] and multivariate analysis [HR = 1.594, 95% CI 1.206-2.106, p = 0.001]. Moreover, tumor PD-L2 expression was inversely associated with the lymphocytic reaction in advanced stage colon carcinoma, suggesting that PD-L2 may be upregulated by a compensatory mechanism to inhibit T cell-mediated anticancer immunity. Taken together, these results show that tumor PD-L2 expression may be an independent prognostic factor for survival outcome in patients with advanced stage colon carcinoma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Apoptosis / genetics
  • Biomarkers, Tumor / genetics
  • CD8-Positive T-Lymphocytes / metabolism
  • CD8-Positive T-Lymphocytes / pathology
  • Carcinoma / genetics*
  • Carcinoma / pathology
  • Colorectal Neoplasms / genetics*
  • Colorectal Neoplasms / pathology
  • Disease-Free Survival
  • Female
  • Gene Expression Regulation, Neoplastic / genetics
  • Humans
  • Ligands
  • Male
  • Middle Aged
  • Prognosis
  • Programmed Cell Death 1 Ligand 2 Protein / genetics*
  • Proportional Hazards Models
  • T-Lymphocytes / metabolism
  • T-Lymphocytes / pathology
  • Tumor Microenvironment / genetics*

Substances

  • Biomarkers, Tumor
  • Ligands
  • PDCD1LG2 protein, human
  • Programmed Cell Death 1 Ligand 2 Protein