卵巢癌是最凶险的恶性妇科肿瘤。多形核磷酸酯酶源性抑制细胞（PMN-MDSCs）参与了卵巢癌并与不良结局密切相关。然而，PMN-MDSCs的免疫抑制机制仍然不清楚。通过生物信息学分析和免疫组织化学染色，研究了ANKRD22表达细胞的类型和数量。利用CRISPR-Cas9技术构建了Ankrd22-/- C57BL/6小鼠。通过GM-CSF和IL-6处理并经过荧光激活细胞分选，从骨髓（BM）来源CD11b+Ly6G+Ly6Clow细胞中获得了小鼠PMN-MDSCs，并通过流式细胞仪（FCM）和ELISA评估了PMN-MDSCs的免疫抑制活性。通过FCM确定了CCR2的表达水平和外源性葡萄糖摄取能力。使用RT-qPCR检测来自人类卵巢癌组织中的CD11b+HLA-DR-CD14-CD15+细胞中的ANKRD22表达，并通过χ2检验评估ANKRD22表达与患者临床特征和预后的相关性。我们发现了一个参与调节PMN-MDSCs免疫抑制能力的新蛋白质，ANKRD22。Ankrd22在小鼠CD11b+Ly6G+Ly6Clow细胞中表达高，并可在暴露于模拟微环境刺激后显着下调。Ankrd22的敲除增加了CD11b+Ly6G+Ly6Clow细胞的CCR2表达水平和PMN-MDSCs的免疫抑制活性。来自Ankrd22-/-小鼠的BM来源CD11b+Ly6G+Ly6Clow细胞在肿瘤异种移植小鼠模型中显着促进了卵巢癌细胞的增殖。RNA测序表明，Ankrd22敲除对BM来源CD11b+Ly6G+Ly6Clow细胞中的Wdfy1表达明显增加，并且Wdfy1的异位表达增加了Ankrd22+/+ PMN-MDSCs的Arg1、Inos、Ido和Pdl1水平。出乎意料的是，ANKRD22激活候选小分子化合物减弱了Ankrd22+/+ PMN-MDSCs的免疫抑制活性。最后，我们发现来自原发性卵巢组织中CD11b+HLA-DR-CD14-CD15+细胞中低ANKRD22水平与更高的国际妇产科联合会阶段、更高的复发率和更高的中性粒细胞/淋巴细胞比率相关。这些结果表明，ANKRD22是逆转PMN-MDSCs免疫抑制效应的潜在新靶点。©作者(或其雇主) 2023。在 CC BY-NC 下允许重新使用。不允许商业再利用。由BMJ出版。

Ovarian cancer is the deadliest type of malignant gynecological tumor. Polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) are involved ovarian cancer and are closely related to adverse outcomes. However, the immunosuppressive mechanism of PMN-MDSCs remains elusive.The types and numbers of ANKRD22-expressing cells were investigated by bioinformatics analysis and immunohistochemical staining. Ankrd22-/- C57BL/6 mice were constructed with CRISPR-Cas9 technology. Mouse PMN-MDSCs were obtained from bone marrow (BM)-derived CD11b+Ly6G+Ly6Clow cells sorted by fluorescence-activated cell sorting with treatment of GM-CSF and IL-6, and the immunosuppressive activity of PMN-MDSCs was evaluated by flow cytometry (FCM) and ELISA. The expression level of CCR2 and the exogenous glucose uptake capacity were determined by FCM. RT-qPCR was used to detect ANKRD22 expression in CD11b+HLA-DR-CD14-CD15+ cells from human ovarian cancer tissues, and the correlations of ANKRD22 expression with the clinical characteristics and prognosis of patients were evaluated by the χ2 test.We identified a novel protein involved in regulating the immunosuppressive ability of PMN-MDSCs, ANKRD22. Ankrd22 expression was high in mouse CD11b+Ly6G+Ly6Clow cells and could be significantly downregulated after exposure to a simulated microenvironmental stimulus. Knockout of Ankrd22 increased the expression level of CCR2 of CD11b+Ly6G+Ly6Clow cells and the immunosuppressive activity of PMN-MDSCs. BM-derived CD11b+Ly6G+Ly6Clow cells of Ankrd22-/- mice significantly promoted the proliferation of ovarian cancer cells in tumor xenograft mouse models. Mechanistically, RNA sequencing showed that Wdfy1 expression was obviously increased in Ankrd22-knockout BM-derived CD11b+Ly6G+ Ly6Clow cells and that ectopic expression of Wdfy1 increased the levels of Arg1, Inos, Ido and Pdl1 in Ankrd22+/+ PMN-MDSCs derived from BM-derived CD11b+Ly6G+Ly6Clow cells. Surprisingly, an ANKRD22-activating candidate small-molecule compound attenuated the immunosuppressive activity of Ankrd22+/+ PMN-MDSCs. Finally, we found that low ANKRD22 levels in CD11b+HLA-DR-CD14-CD15+ cells derived from primary ovarian tissues were associated with a more advanced International Federation of Gynecology and Obstetrics stage, a higher recurrence rate, and a higher neutrophil-to-lymphocyte ratio.These results suggest that ANKRD22 is a potential novel target for reversing the immunosuppressive effects of PMN-MDSCs.© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.