Department of Nephrology, Chongqing Traditional Chinese Medicine Hospital, Chongqing, China.
Department of Endocrine and Breast Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China.
J Immunol Res. 2022 May 14;2022:1260423. doi: 10.1155/2022/1260423. eCollection 2022.
Clear cell renal cell cancer (ccRCC) is a tumor of high malignancy, which can escape apoptosis. The tumor protein p53-inducible nuclear protein 2 (TP53INP2), known as an autophagy protein, is the essential part for autophagosome formation and sensitizes cells to apoptosis. Our study is aimed at exploring the role of TP53INP2 in ccRCC. We have identified the autophagy-related genes (ARGs) of differential expression in ccRCC patients with the help of the TCGA database by bioinformatics analysis. Our assays of quantitative real-time polymerase chain reaction (qRT-PCR) and western blot were for the determination on the both levels of mRNA and protein. Overexpression of TP53INP2 on cellular proliferation, migration, and apoptosis of ccRCC was verified in the ways of performing CCK-8, wound scrape, transwell and flow cytometry assays , and a mice tumor model . Transmission electron microscopy was used to measure autophagy formation. The underlying mechanisms of TP53INP2 on ccRCC were determined via coimmunoprecipitation. TP53INP2 was found highly associated with an outcome of worse overall survival (OS) in Kaplan-Meier curves, and this parameter in ccRCC tissues was also lower than the normal tissues. Overexpression of TP53INP2 inhibited ccRCC cellular proliferation, migration, and invasion, as well as the tumor growth of mice. Those cells treated with autophagy inhibitor chloroquine (CQ) or TP53INP2 increased the apoptosis rate. TP53INP2 promoted autophagy formation and elevated the ratio of LC3 II/LC3 I. However, TP53INP2 did not significantly decrease the p-mTOR level. In addition, TP53INP2 activates the expressions of caspase-3, caspase-8, and PARP. Caspase-8 and TNF receptor associated factor 6 (TRAF6) were found to bind to each other in the presence of TP53INP2. TP53INP2 induces apoptosis in ccRCC cells through caspase-8/TRAF6 pathway, rather than the autophagy-dependent pathway.
透明细胞肾细胞癌（ccRCC）是一种恶性程度较高的肿瘤，能够逃避细胞凋亡。肿瘤蛋白 p53 诱导核蛋白 2（TP53INP2）作为一种自噬蛋白，是自噬体形成的必需部分，并使细胞对细胞凋亡敏感。我们的研究旨在探讨 TP53INP2 在 ccRCC 中的作用。我们通过生物信息学分析，利用 TCGA 数据库鉴定了 ccRCC 患者差异表达的自噬相关基因（ARGs）。我们通过定量实时聚合酶链反应（qRT-PCR）和 Western blot 检测了 ARGs 在 mRNA 和蛋白水平的表达。通过 CCK-8、划痕实验、Transwell 和流式细胞术检测细胞增殖、迁移和凋亡，以及小鼠肿瘤模型，验证了 TP53INP2 对 ccRCC 细胞的过表达作用。通过免疫共沉淀确定了 TP53INP2 对 ccRCC 的潜在作用机制。在 Kaplan-Meier 曲线中发现 TP53INP2 与总生存期（OS）较差的结果高度相关，ccRCC 组织中的这一参数也低于正常组织。TP53INP2 的过表达抑制了 ccRCC 细胞的增殖、迁移和侵袭，以及小鼠肿瘤的生长。用自噬抑制剂氯喹（CQ）或 TP53INP2 处理的细胞，凋亡率增加。TP53INP2 促进自噬体的形成，增加 LC3 II/LC3 I 的比值。然而，TP53INP2 并没有显著降低 p-mTOR 水平。此外，TP53INP2 激活了 caspase-3、caspase-8 和多聚（ADP-核糖）聚合酶（PARP）的表达。在存在 TP53INP2 的情况下，caspase-8 和 TNF 受体相关因子 6（TRAF6）被发现相互结合。TP53INP2 通过 caspase-8/TRAF6 途径而非自噬依赖性途径诱导 ccRCC 细胞凋亡。
