Lu Yebin, Chen Qizhen, Zhu Shuai, Gong Xuejun
Pancreas Surgery, Xiangya Hospital, Central South University, Changsha, 410008, Hunan Province, China.
Pancreas Surgery, Xiangya Hospital, Central South University, Changsha, 410008, Hunan Province, China.
Exp Cell Res. 2023 Nov 15;432(2):113764. doi: 10.1016/j.yexcr.2023.113764. Epub 2023 Sep 1.
Pancreatic cancer (PC) cell immune escape is a crucial element in PC malignant development. Some previous studies have reported that LncRNA NNT-AS1 played a carcinogenic role in various tumors. However, the effect of lncRNA NNT-AS1 in PC cell immune escape remains unclear. To evaluate PC cell immune escape, PC cells were co-cultured with CD8 T cells under a hypoxic condition. PC cell proliferation and migration were evaluated using the colony formation assay and transwell assay. CD8 T cell proliferation and aoptosis were measured using the carboxy fluorescein diacetate succinimidyl ester (CFSE) assay and flow cytometry. The secretion of antitumor cytokines was assessed using enzyme-linked immunosorbent assay (ELISA). The molecular interactions were analyzed using chromatin immunoprecipitation (ChIP), RNA immunoprecipitation (RIP), or dual-luciferase reporter gene assays. A tumor xenograft model was established to evaluate the effects of lncRNA NNT-AS1 on PC in vivo. It was found that lncRNA NNT-AS1 was highly expressed in PC, and its silencing inhibited hypoxia-induced PC cell growth and immune escape in vivo and in vitro. Mechanically, HIF-1α transcriptionally activated NNT-AS1 expression and NNT-AS1 increased ITGB1 stability and expression in a METTL3-HuR dependent manner. ITGB1 overexpression reversed the inhibitory effects of NNT-AS1 knockdown on hypoxia-induced PC cell immune escape. In conclusion, Hypoxia promoted PC cell immune escape through lncRNA NNT-AS1/METTL3-HuR-mediated mA modification to increase ITGB1 expression, which provided a theoretical foundation and a potential therapeutic target for PC.
胰腺癌（PC）细胞的免疫逃逸是PC恶性发展的关键因素。先前的一些研究报道，长链非编码RNA NNT-AS1在各种肿瘤中发挥致癌作用。然而，lncRNA NNT-AS1在PC细胞免疫逃逸中的作用仍不清楚。为了评估PC细胞的免疫逃逸，将PC细胞与CD8 T细胞在缺氧条件下共培养。使用集落形成试验和Transwell试验评估PC细胞的增殖和迁移。使用羧基荧光素二乙酸琥珀酰亚胺酯（CFSE）试验和流式细胞术检测CD8 T细胞的增殖和凋亡。使用酶联免疫吸附测定（ELISA）评估抗肿瘤细胞因子的分泌。使用染色质免疫沉淀（ChIP）、RNA免疫沉淀（RIP）或双荧光素酶报告基因试验分析分子相互作用。建立肿瘤异种移植模型以评估lncRNA NNT-AS1在体内对PC的影响。研究发现，lncRNA NNT-AS1在PC中高表达，其沉默在体内和体外均抑制缺氧诱导的PC细胞生长和免疫逃逸。机制上，HIF-1α转录激活NNT-AS1的表达，NNT-AS1以METTL3-HuR依赖的方式增加ITGB1的稳定性和表达。ITGB1的过表达逆转了NNT-AS1敲低对缺氧诱导的PC细胞免疫逃逸的抑制作用。总之，缺氧通过lncRNA NNT-AS1/METTL3-HuR介导的m6A修饰增加ITGB1表达来促进PC细胞免疫逃逸，这为PC提供了理论基础和潜在的治疗靶点。
