PLA2G2A+ cancer-associated fibroblasts mediate pancreatic cancer immune escape via impeding antitumor immune response of CD8+ cytotoxic T cells

Cancer Lett. 2023 Apr 1:558:216095. doi: 10.1016/j.canlet.2023.216095. Epub 2023 Feb 14.

Abstract

Our previous research defined a novel metabolic cancer associated fibroblasts subset (meCAFs) enriched in loose-type pancreatic ductal adenocarcinoma (PDAC) and related to CD8+ T cells accumulation. Consistently, the abundance of meCAFs was associated with poor prognosis but better immunotherapy responses in PDAC patients. However, the metabolic characteristic of meCAFs and its cross-talk with CD8+ T cells remain to be elucidated. In this study, we identified PLA2G2A as a marker of meCAFs. In particular, the abundance of PLA2G2A+ meCAFs was positively related to the accumulation of total CD8+ T cells and negatively correlated with clinical outcomes of PDAC patients and infiltration of intratumoral CD8+ T cells. We demonstrated that PLA2G2A+ meCAFs substantially attenuated the antitumor ability of tumor infiltrating CD8+ T cells and facilitated tumor immune escape in PDAC. Mechanistically, PLA2G2A regulated the function of CD8+ T cells as a pivotal soluble mediator via MAPK/Erk and NF-κB signaling pathways. In conclusion, our study identified the unrecognized role of PLA2G2A+ meCAFs in promoting tumor immune escape by impeding the antitumor immune function of CD8+ T cells, and strongly suggested PLA2G2A as a promising biomarker and therapeutic target for immunotherapy in PDAC.

Keywords: CD8(+) cytotoxic T cells; Metabolic cancer-associated fibroblasts; PLA2G2A; Pancreatic ductal adenocarcinoma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • CD8-Positive T-Lymphocytes
  • Cancer-Associated Fibroblasts* / metabolism
  • Carcinoma, Pancreatic Ductal* / pathology
  • Group II Phospholipases A2
  • Humans
  • Immunity
  • Pancreatic Neoplasms* / pathology
  • T-Lymphocytes, Cytotoxic / metabolism
  • Tumor Microenvironment

Substances

  • PLA2G2A protein, human
  • Group II Phospholipases A2