PO.TB10.16 · 肿瘤生物学
探讨OST4对卵巢癌肿瘤发生和免疫微环境的影响
Examining OST4's impact on tumorigenesis and immune microenvironment in ovarian cancer
该海报暂无可下载的资料
AACR 官方页面
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
引言：卵巢癌仍然是妇科最致命的恶性肿瘤之一，其特征为高度转移倾向、强耐药性以及对免疫治疗应答有限。蛋白质糖基化在这些过程中发挥关键作用，使其成为极具吸引力的治疗开发靶点。寡糖基转移酶（OST）复合物催化N连接糖基化的核心步骤，尤为重要。在OST各亚基中，OST4是关键的调控元件。既往研究表明，OST4表达调节蛋白质N-糖基化的效率，并被公认为头颈癌的预后标志物，且与PD-L1表达相关。然而，OST4等糖基化相关基因在卵巢癌发展和肿瘤微环境中免疫细胞活性中的作用仍不明确。本研究探讨OST4在卵巢癌中的功能并评估其作为治疗靶点的潜力。
方法：我们对癌症基因组图谱（TCGA）和单细胞RNA测序数据集进行了全面的数据挖掘，以识别卵巢癌中与OST4相关的通路及其免疫相关效应。使用siRNA在卵巢癌细胞系（OVCAR4和OVCAR8）中敲低OST4表达。测定细胞迁移和侵袭以评估转移潜能，并通过XTT实验评估增殖。进行Western blot分析以考察相关信号通路和下游效应因子。从转染OST4 siRNA和scRNA的卵巢癌细胞中收集肿瘤条件培养基（TCM），在完全培养基中孵育48小时。使用transwell迁移实验测定与TCM共培养的T细胞的浸润。
结果：发现OST4在卵巢癌中高表达。基于OST4表达水平的患者分层揭示了与巨噬细胞和T细胞浸润的关联。通路分析表明OST4可能调控未折叠蛋白反应（UPR）。沉默OST4抑制了卵巢癌细胞的迁移、侵袭和增殖。Western blot分析进一步表明，OST4敲低降低了UPR通路核心组分IRE1alpha的表达。与对照TCM相比，来源于OST4沉默OC细胞的TCM存在时，浸润的CD8 + T细胞数量增加。
结论：总之，OST4影响卵巢癌进展和CD8 + T细胞浸润，可能是通过激活UPR通路实现的。靶向OST4可能为卵巢癌提供一种前景广阔的治疗方法。
查看英文原文 English abstract
IntroductionOvarian cancer remains one of the deadliest malignancies in gynecology, characterized by a high tendency for metastasis, strong drug resistance, and limited response to immunotherapy. Protein glycosylation plays a critical role in these processes, making it an attractive target for therapeutic development. The oligosaccharidyltransferase (OST) complex, which catalyzes a central step in N-linked glycosylation, is of particular importance. Among OST subunits, OST4 serves as a key regulatory element. Previous studies indicate that OST4 expression modulates the efficiency of protein N-glycosylation and has been recognized as a prognostic marker in head and neck cancers, with connections to PD-L1 expression. However, the role of glycosylation-related genes such as OST4 in ovarian cancer development and immune cell activity within the tumor microenvironment remains unclear. This study explores the function of OST4 in ovarian cancer and assesses its potential as a therapeutic target.MethodsWe employed comprehensive data mining of The Cancer Genome Atlas (TCGA) and single-cell RNA sequencing datasets to identify pathways linked to OST4 in ovarian cancer and its immune-related effects. OST4 expression was knocked down in ovarian cancer cell lines (OVCAR4 and OVCAR8) using siRNA. Cell migration and invasion were measured to evaluate metastatic potential, and proliferation was assessed via XTT assays. Western blot analysis was performed to examine associated signaling pathways and downstream effectors. Tumor Conditioned Medium (TCM) was collected from ovarian cancer cells transfected with OST4 siRNA and scRNA, incubated in complete medium for 48 hours. The transwell migration assay was used to determine the infiltration of T cells cultured with the TCM. ResultsOST4 was found to be highly expressed in ovarian cancer. Patient stratification based on OST4 expression levels revealed associations with macrophage and T-cell infiltration. Pathway analysis indicated that OST4 may regulate the unfolded protein response (UPR). Silencing OST4 suppressed ovarian cancer cell migration, invasion, and proliferation. Western blot analysis further demonstrated that OST4 knockdown decreased the expression of IRE1alpha, a central component of the UPR pathway. The number of infiltrated CD8 + T cells increased in the presence of TCM derived from OST4-silenced OC cells compared to control TCM.ConclusionIn conclusion, OST4 influences ovarian cancer progression and CD8 + T cell infiltration, potentially through activation of the UPR pathway. Targeting OST4 may offer a promising therapeutic approach for ovarian cancer.
利益披露 Disclosure
M. Gu, None.