Long non-coding RNA Lnc-Tim3 exacerbates CD8 T cell exhaustion via binding to Tim-3 and inducing nuclear translocation of Bat3 in HCC

Cell Death Dis. 2018 May 1;9(5):478. doi: 10.1038/s41419-018-0528-7.

Abstract

Although one of the first comprehensive examinations of long non-coding RNA (lncRNA) expression was performed in human CD8 T lymphocytes, little is known about their roles in CD8 T cells functions during the progression of hepatocellular carcinoma (HCC). Here, we show that Lnc-Tim3 is upregulated and negatively correlates with IFN-γ and IL-2 production in tumor-infiltrating CD8 T cells of HCC patients. Lnc-Tim3 plays a pivotal role in stimulating CD8 T exhaustion and the survival of the exhausted CD8 T cells. Mechanistically, Lnc-Tim3 specifically binds to Tim-3 and blocks its interaction with Bat3, thus suppressing downstream Lck/ NFAT1/AP-1 signaling, leading to nuclear localization of Bat3, and enhancing p300-dependent p53 and RelA transcriptional activation of anti-apoptosis genes including MDM2 and Bcl-2. In summary, Lnc-Tim3 promotes T cell exhaustion, a phenotype which is correlated with compromised anti-tumor immunity, suggesting that Lnc-Tim3 and its associated signaling pathways may influence the outcome of cancer therapies aimed at modulating the acquired immune system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Active Transport, Cell Nucleus / immunology
  • CD8-Positive T-Lymphocytes / immunology*
  • CD8-Positive T-Lymphocytes / pathology
  • Carcinoma, Hepatocellular / immunology*
  • Carcinoma, Hepatocellular / pathology
  • Cell Nucleus / immunology*
  • Cell Nucleus / pathology
  • Female
  • Hepatitis A Virus Cellular Receptor 2 / immunology*
  • Humans
  • Liver Neoplasms / immunology*
  • Liver Neoplasms / pathology
  • Male
  • Molecular Chaperones / immunology*
  • Neoplasm Proteins / immunology*
  • RNA, Long Noncoding / immunology*
  • RNA, Neoplasm / immunology*
  • Signal Transduction / immunology

Substances

  • BAG6 protein, human
  • HAVCR2 protein, human
  • Hepatitis A Virus Cellular Receptor 2
  • Molecular Chaperones
  • Neoplasm Proteins
  • RNA, Long Noncoding
  • RNA, Neoplasm