Cytolytic activity score as a biomarker for antitumor immunity and clinical outcome in patients with gastric cancer. (26th March 2021)

• Record Type: Journal Article
• Authors: Hu, Qingjiang; Nonaka, Kentaro; Wakiyama, Hiroaki; Miyashita, Yu; Fujimoto, Yoshiaki; Jogo, Tomoko; Hokonohara, Kentaro; Nakanishi, Ryota; Hisamatsu, Yuichi; Ando, Koji; Kimura, Yasue; Masuda, Takaaki; Oki, Eiji; Mimori, Koshi; Oda, Yoshinao; Mori, Masaki
• Is Part Of: Cancer medicine. Volume 10:Number 9(2021)
• Page Start: 3129
• Page End: 3138
• Publication Date: 2021-03-26
• Subjects: biomarkers -- gastric cancer -- genomics -- immunology -- TCGA; 616.994005
• DOI: 10.1002/cam4.3828
• Languages: English
• ISSNs: 2045-7634

Abstract

Abstract: Background: A simple measure of immune cytolytic activity (CYT) base on mRNA expression levels of two genes, GZMA and PRF1, was recently reported. Here, we aimed to evaluate the CYT score's potential as a measure of antitumor immunity and predictor of clinical outcome in gastric cancer (GC) patients. Materials and Methods: We evaluated the correlations between tumor‐infiltrating immune cells and the CYT score in 238 GC samples from The Cancer Genome Atlas (TCGA). Next, we investigated CYT score associations with molecular subtypes, somatic mutation load, and immune checkpoint molecules in GC samples from TCGA and Asian Cancer Research Group (ACRG). Moreover, we evaluated the clinical significance of the CYT score calculated by reverse transcription (RT)‐quantitative PCR (qPCR) data in 123 GC samples and the association of the CYT score with the response to anti‐PD‐1 therapy in 7 GC samples from Kyushu University Hospital. Results: The CYT score positively correlated with the proportions of tumor‐infiltrating CD8+ T cells and macrophages and negatively correlated with the proportion of regulatory T cells in GC tissues. A high CYT score was associated with common immune checkpoint molecules, a high mutation, the Epstein–Barr virus subtype, and the microsatellite instability subtype in GC. Moreover, a low CYT score was a poor prognosis factor in patients with GC. Finally, the CYT score was higher in a responder to anti‐PD‐1 therapy compared to nonresponders. Conclusion: The CYT score reflects antitumor immunity and predicts clinical outcome in GC patients. Abstract : High CYT score was associated with tumor‐infiltrating CD8+ T cells, EBV, MSI‐H, high tumor mutation load, and upregulated immune checkpoint molecules in gastric cancer. Moreover, the CYT score was associated with prognosis and response to the anti‐PD‐1 antibody in gastric cancer patients.