Elimination of oncogenic KRAS in genetic mouse models eradicates pancreatic cancer by inducing FAS-dependent apoptosis by CD8+ T cells

Dev Cell. 2023 Sep 11;58(17):1562-1577.e8. doi: 10.1016/j.devcel.2023.07.025. Epub 2023 Aug 24.

Abstract

Oncogenic KRASG12D (KRAS) is critical for the initiation and maintenance of pancreatic ductal adenocarcinoma (PDAC) and is a known repressor of tumor immunity. Conditional elimination of KRAS in genetic mouse models of PDAC leads to the reactivation of FAS, CD8+ T cell-mediated apoptosis, and complete eradication of tumors. KRAS elimination recruits activated CD4+ and CD8+ T cells and promotes the activation of antigen-presenting cells. Mechanistically, KRAS-mediated immune evasion involves the epigenetic regulation of Fas death receptor in cancer cells, via methylation of its promoter region. Furthermore, analysis of human RNA sequencing identifies that high KRAS expression in PDAC tumors shows a lower proportion of CD8+ T cells and demonstrates shorter survival compared with tumors with low KRAS expression. This study highlights the role of CD8+ T cells in the eradication of PDAC following KRAS elimination and provides a rationale for the combination of KRAS targeting with immunotherapy to control PDAC.

Keywords: CD8(+) T cells; FAS-FASL; KRAS(G12D); oncogenic KRAS; pancreatic cancer.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis
  • CD8-Positive T-Lymphocytes
  • Carcinoma, Pancreatic Ductal* / genetics
  • Epigenesis, Genetic
  • Humans
  • Mice
  • Pancreatic Neoplasms* / genetics
  • Proto-Oncogene Proteins p21(ras)* / genetics

Substances

  • Proto-Oncogene Proteins p21(ras)
  • Hras protein, mouse