Correlation of low B7-H6 expression with efficacy of immunotherapy inpatients with melanoma.

person Jian Chen The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, China info_outline Jian Chen, Deqin Li, Weiwei Zhang, Shujie Song, Dengjun Sun, Ningning Luo, Huan Yi, Yingxue Qi, Mengmeng Li, Tingting Sun, Chuang Qi

Authors person Jian Chen The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, China info_outline Jian Chen, Deqin Li, Weiwei Zhang, Shujie Song, Dengjun Sun, Ningning Luo, Huan Yi, Yingxue Qi, Mengmeng Li, Tingting Sun, Chuang Qi Organizations The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, China, The Second Medical College of Binzhou Medical University, Yantai, China, The Medical Department, Jiangsu Simcere Diagnostics Co., Ltd; Nanjing Simcere Medical Laboratory Science Co., Ltd; The State Key Lab of Translational Medicine and Innovative Drug Development, Jiangsu Simcere Diagnostics Co., Ltd, Nanjing, China, The Medical Department, Nanjing Simcere Medical Laboratory Science Co., Ltd, Nanjing, China Abstract Disclosures Research Funding No funding received None. Background: B7-H6 (NCR3LG1) can bind to NKp30 to trigger antitumor NK cell activation and cytokine secretion. Our previous studies have shown that in gastric cancer, B7-H6 high expression was associated with better prognosis and the low expression of B7-H6 group was correlated with better immune microenvironment. However, the effect of B7-H6 expression on immunotherapy is unknown. Herein, we used the data from a clinically annotated cohort of melanoma patients treated with ICI to analyze the influence of B7-H6 expression on immunotherapy. Methods: The gene expression profile, gene mutation information and clinical data were extracted from the supplementary data in melanoma cohort (PMID: 31792460). Maximally selected rank statistics was used to select the optimum threshold for B7-H6 expression, and the patients was divided into two groups according to the expression of B7-H6, high group and low group. Kaplan-Meier survival analysis was used to evaluate the influence of B7-H6 expression on OS prognosis. Associations between variables and OS survival were tested using univariate and multivariate Cox and displayed by forest (R package). Results: We selected 3.14 as the optimum threshold of B7-H6 expression, and the patients was divided into high group (B7-H6 expression＞3.14) and low group (B7-H6 expression≤3.14). The results showed that low group was significantly associated with longer overall survival (p value = 0.048) in cohort of melanoma patients treated with anti-PD1 ICI, which was consistent with our previous results that low expression of B7-H6 group was correlated with better immune microenvironment. We selected primary lesion type, TMB and the expression of B7-H6 factors for univariate and multivariate analysis. TMB-H (top 25%) (p value = 0.051) and B7-H6 (p value = 0.051) low expression were associated with a better OS. Then the patients were divided into four groups according to the TMB and B7-H6 expression and analyzed the difference in the four groups. The results showed that in patients with TMB-L, B7-H6 low group had significant better OS than the B7-H6 high group (p value = 0.032). Conclusions: The low B7-H6 expression was correlated with better efficacy immunotherapy. The effect of B7-H6 expression on immunotherapy needs to be further prospective trial validation.