Niu N, Shen W, Zhong Y, et al. - Given the low response rate to single-agent immune checkpoint inhibitors in high-grade serous ovarian carcinoma (HGSC), researchers herein sought for alternative biomarkers and targets to guide patient selection and new therapeutic strategies in HGSC. The clinical significance of novel immune modulators, including B7–H4, IDO1, Tim3, IL6, and IL-8, was examined in patients with HGSC. Among a total of 48 patients with HGSCs, consisting of 24 cases sensitive and 24 resistant to standard paclitaxel and carboplatin chemotherapy, the expression levels of immune checkpoints were analyzed and expression profiles with clinicopathologic features including response, progression-free survival, and overall survival were compared. Findings revealed significantly higher expression of B7–H4 and IDO1 in drug-resistant cases of HGSOC. They indicated worse overall survival and disease-free survival in correlation with high levels of B7–H4 and IDO1. Based on findings, researchers suggest B7–H4 and IDO1 as novel targets that maintain the immune barrier in patients with HGSOCs.