目的：探讨细胞色素c氧化酶组装因子6（COA6）在胃癌中的表达特征、临床意义及其对胃癌细胞恶性生物学行为的调控作用与分子机制。方法：通过TIMER 2.0、人类蛋白质图谱（HPA）和UALCAN等公共数据库分析COA6在多种肿瘤组织中的mRNA表达水平及部分蛋白表达信息，并分析其与临床病理特征的关联。构建靶向COA6的敲低和过表达慢病毒载体，分别转染SGC-7901和MGC-803细胞，构建COA6稳定修饰细胞模型。敲低体系设置shCOA6?1、shCOA6?2、shCOA6?3实验组及阴性对照shCOA6-NC组；过表达体系设置COA6过表达（OE）组与空载病毒（Vector）对照组，采用WB法验证各组COA6的敲低与过表达效率。随后，分别采用细胞计数实验检测细胞增殖活性，Transwell实验评价细胞侵袭能力，划痕愈合实验观测细胞迁移能力，Annexin V-FITC/PI双染色流式检测细胞凋亡水平，同时利用WB法检测AMPK/mTOR通路核心蛋白的磷酸化水平。结果：COA6在多种肿瘤中呈异常表达，且其表达水平与胃癌临床分期、病理分级、淋巴结转移及TP53突变状态有关联。功能实验表明，敲低COA6可显著抑制胃癌细胞增殖、侵袭和迁移，并促进凋亡（均P < 0.000 1）；而过表达COA6则产生相反效应。机制研究发现，COA6敲低导致p-AMPK表达上调、p-mTOR表达下调，AMPK抑制剂Compound C处理可逆转COA6敲低诱导的p-AMPK升高和p-mTOR降低，提示COA6可能与AMPK活化受抑和mTOR磷酸化增强有关。结论：COA6在胃癌中高表达且与部分临床病理特征有关联，其可能通过调控AMPK/mTOR信号通路促进胃癌细胞增殖、侵袭和迁移，并抑制凋亡。

Objective: To investigate the expression characteristics and clinical significance of cytochrome c oxidase assembly factor 6 (COA6) in gastric cancer, as well as its regulatory effects and molecular mechanisms on the malignant biological behaviors of gastric cancer cells. Methods: The TIMER 2.0, The Human Protein Atlas (HPA), and UALCAN public databases were utilized to analyze the mRNA expression levels and partial protein expression information of COA6 in pan-cancer tissues, and to assess its association with clinicopathological features. Lentiviral vectors carrying COA6 knockdown and overexpression sequences were constructed and transfected into human gastric cancer SGC-7901 and MGC-803 cell lines to establish stably modified COA6 cell models. For the knockdown experiment, three experimental groups (shCOA6?1, shCOA6?2, shCOA6?3) and a negative control group (shCOA6-NC) were established; for the overexpression experiment, an OE group (COA6 overexpression) and a Vector group (empty lentivirus control) were set up. WB was performed to verify the efficiencies of COA6 knockdown and overexpression in each group. Subsequently, cell proliferative activity was determined via cell counting assay, cell invasive capacity was evaluated using Transwell assay, and cell migratory ability was examined by wound healing assay. Annexin V-FITC/PI double staining combined with flow cytometry was adopted to quantify cellular apoptosis, and WB was also used to detect the phosphorylation levels of core proteins in the AMPK/mTOR signaling pathway. Results: COA6 was aberrantly expressed in multiple cancers, and its expression level was associated with clinical stage, pathological grade, lymph node metastasis, and TP53 mutation status in gastric cancer. Functionally, COA6 knockdown inhibited malignant phenotypes and promoted apoptosis (all P < 0.000 1), while overexpression had opposite effects. Mechanistically, COA6 knockdown increased p-AMPK levels and decreased p-mTOR levels. This effect was reversed by treatment with the AMPK inhibitor Compound C, which abrogated the COA6 knockdown-induced increase in p-AMPK and decrease in p-mTOR. Conclusion: COA6 is highly expressed in gastric cancer and is associated with several clinicopathological features. It may promote proliferation, invasion, and migration, while inhibiting apoptosis of gastric cancer cells by regulating the AMPK/mTOR signaling pathway.

国家自然科学基金（81960536）；贵州省科技厅项目（黔科合基础[2020]1Y379）