School of Basic Medical Sciences, Nanchang University, Nanchang, 330031, People's Republic of China.
Jiangxi Institute of Respiratory Disease, The First Affiliated Hospital of Nanchang University, Nanchang, 330006, People's Republic of China.
Cell Commun Signal. 2022 Aug 30;20(1):133. doi: 10.1186/s12964-022-00936-x.
Glycogen-Interacting Protein 1 (GNIP1), an E3 ligase, is a member of the tripartite motif (TRIM) family proteins. Current studies on GNIP1 mainly focus on glycogen metabolism. However, the function and molecular mechanisms of GNIP1 in regulating autophagy still remains unclear. This study aimed to investigate the regulatory mechanism of GNIP1 in regulating autophagy in non-small cell lung cancer (NSCLC).
Crystal violet staining assays were used to evaluate the ability of cell growth and proliferation. Transwell and scratch wound healing assays were used to evaluate the cell migration ability. The protein expressions were measured by western blot and immunohistochemistry. Co-immunoprecipitation assays determined the protein-protein interactions. The in vivo effect of GNIP1 on tumor growth was determined by xenograft assay.
We found that GNIP1 was overexpressed in tumor tissues and the expression level of GNIP1 was related to the poor prognosis and the survival time of NSCLC patients. In non-small cell lung cancer (NSCLC), GNIP1 increased proliferation and migration of cancer cells by promoting autophagy. Mechanistic studies indicated that GNIP1, as a scaffold protein, recruited BECN1 and LC3B to promote the formation of autophagosomes. Besides, GNIP1 mediated the degradation of 14-3-3ζ, the negative regulator of VPS34 complex, thus promoting autophagy. Overexpressing GNIP1 promoted tumorigenesis and enhanced autophagy in xenograft models.
GNIP1 promotes proliferation and migration of NSCLC cells through mediating autophagy, which provides theoretical basis for targeting GNIP1 as anti-cancer drugs. Video Abstract.
糖原相互作用蛋白 1（GNIP1）作为一种 E3 连接酶，是三联基序（TRIM）家族蛋白的成员。目前关于 GNIP1 的研究主要集中在糖原代谢上。然而，GNIP1 调节自噬的功能和分子机制尚不清楚。本研究旨在探讨 GNIP1 在非小细胞肺癌（NSCLC）中调节自噬的调控机制。
采用结晶紫染色法评估细胞生长和增殖能力。Transwell 和划痕愈合实验用于评估细胞迁移能力。通过 Western blot 和免疫组化检测蛋白表达。通过免疫共沉淀实验确定蛋白质-蛋白质相互作用。通过异种移植实验确定 GNIP1 对肿瘤生长的体内影响。
我们发现 GNIP1 在肿瘤组织中过度表达，GNIP1 的表达水平与 NSCLC 患者的不良预后和生存时间有关。在非小细胞肺癌（NSCLC）中，GNIP1 通过促进自噬来增加癌细胞的增殖和迁移。机制研究表明，GNIP1 作为支架蛋白，募集 BECN1 和 LC3B 以促进自噬体的形成。此外，GNIP1 介导了 VPS34 复合物负调节因子 14-3-3ζ 的降解，从而促进了自噬。过表达 GNIP1 促进了异种移植模型中的肿瘤发生和自噬增强。
GNIP1 通过介导自噬促进 NSCLC 细胞的增殖和迁移，为靶向 GNIP1 作为抗癌药物提供了理论依据。
