High GILT Expression and an Active and Intact MHC Class II Antigen Presentation Pathway Are Associated with Improved Survival in Melanoma.

Abstract

The MHC class I Ag presentation pathway in melanoma cells has a well-established role in immune-mediated destruction of tumors. However, the clinical significance of the MHC class II Ag presentation pathway in melanoma cells is less clear. In Ag-presenting cells, IFN-γ-inducible lysosomal thiol reductase (GILT) is critical for MHC class II-restricted presentation of multiple melanoma Ags. Although not expressed in benign melanocytes of nevi, GILT and MHC class II expression is induced in malignant melanocytes in a portion of melanoma specimens. Analysis of The Cancer Genome Atlas cutaneous melanoma data set showed that high GILT mRNA expression was associated with improved overall survival. Expression of IFN-γ, TNF-α, and IL-1β was positively associated with GILT expression in melanoma specimens. These cytokines were capable of inducing GILT expression in human melanoma cells in vitro. GILT protein expression in melanocytes was induced in halo nevi, which are nevi undergoing immune-mediated regression, and is consistent with the association of GILT expression with improved survival in melanoma. To explore potential mechanisms of GILT's association with patient outcome, we investigated pathways related to GILT function and expression. In contrast to healthy skin specimens, in which the MHC class II pathway was nearly uniformly expressed and intact, there was substantial variation in the MHC class II pathway in the The Cancer Genome Atlas melanoma specimens. Both an active and intact MHC class II pathway were associated with improved overall survival in melanoma. These studies support a role for GILT and the MHC class II Ag presentation pathway in melanoma outcome.

• Authors: Kenneth H Buetow, Lydia R Meador, Hari Menon, Yih-Kuang Lu, Jacob Brill, Haiyan Cui, Denise J Roe, David J DiCaudo, K Taraszka Hastings
• Journal: Journal of immunology (Baltimore, Md. : 1950) (J Immunol) Vol. 203 Issue 10 Pg. 2577-2587 (11 15 2019) ISSN: 1550-6606 [Electronic] United States
• PMID: 31591149 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2019 by The American Association of Immunologists, Inc.

Chemical References

• Histocompatibility Antigens Class II
• IFNG protein, human
• RNA, Messenger
• Recombinant Proteins
• Interferon-gamma
• IFI30 protein, human
• Oxidoreductases Acting on Sulfur Group Donors

Topics

• Adolescent
• Antigen Presentation (immunology)
• Cell Line, Tumor
• Female
• HEK293 Cells
• Histocompatibility Antigens Class II (metabolism)
• Humans
• Interferon-gamma (metabolism, pharmacology)
• Male
• Melanoma (immunology, mortality, pathology)
• Oxidoreductases Acting on Sulfur Group Donors (genetics, metabolism)
• RNA, Messenger (genetics)
• Real-Time Polymerase Chain Reaction
• Recombinant Proteins (pharmacology)
• Skin Neoplasms (immunology, mortality, pathology)
• Survival Rate
• Young Adult