CELL INTELLIGENCE · 肿瘤细胞治疗研究

BACKGROUND: We aimed to investigate the distinct immunological characteristics of the tumor immune microenvironment in epithelial ovarian cancer (EOC) according to BRCA1/2 mutations status and differential PD-1 expression levels. METHODS: Tumor-infiltrating lymphocytes (TILs) were collected from patients with newly diagnosed advanced-stage EOC (YUHS cohort, n=117). This YUHS cohort was compared with The Cancer Genome Atlas (TCGA) data for ovarian serous cystadenocarcinoma (n=482), in terms of survival outcomes and immune-related gene profiles according to BRCA1/2 status. We used multicolor flow cytometry to characterize the immune phenotypes and heterogeneity of TILs with or without BRCA1/2 mutations. In vitro functional assays were conducted to evaluate the reinvigorating ability of CD8 + TILs on anti-PD-1 treatment. RESULTS: We found that EOC patients with BRCA1/2 mutations ( BRCA1/2 mt) exhibited better survival outcomes and significantly higher tumor mutation burden (TMB), compared with BRCA1/2 non-mutated ( BRCA1/2 wt) patients. Furthermore, CD8 + TILs within BRCA1/2 mt tumors displayed characteristics indicating more severe T-cell exhaustion than their BRCA1/2 wt counterparts. Notably, the capacity for anti-PD-1-mediated reinvigoration of CD8 + TILs was significantly greater in BRCA1/2 wt tumors compared with BRCA1/2 mt tumors. Additionally, within the BRCA1/2 wt group, the frequency of PD-1 high CD8 + TILs was positively correlated with the reinvigoration capacity of CD8 + TILs after anti-PD-1 treatment. CONCLUSION: Our results highlight unique immune features of CD8 + TILs in EOC and a differential response to anti-PD-1 treatment, contingent on BRCA1/2 mutation status. These findings suggest that immune checkpoint blockade may be a promising frontline therapeutic option for selected BRCA1/2 wt EOC patients.