目的： 检测LINC00997在胃贲门腺癌（GCA）组织及胃癌细胞中的表达，分析其表达与患者临床病理特征和预后的关系，探讨敲减LINC00997对胃癌SGC7901细胞迁移、侵袭及上皮间质转化（EMT）的影响。 方法： 基于TCGA和GTEx数据库分析LINC00997在胃癌组织中的表达及其与患者预后的关系。应用qPCR法检测68例GCA组织和相应癌旁组织以及胃癌细胞中LINC00997的表达水平，分析其表达与患者临床病理特征及预后的关系。通过划痕愈合、Transwell侵袭实验分别检测敲减LINC00997 对 SGC7901 细胞迁移和侵袭的影响，qPCR 法和 WB 法检测敲减LINC00997对EMT 相 关 标 志 物 E-cadherin、N-cadherin及vimentin表达的影响。 结果： LINC00997在胃癌组织中的表达水平显著高于癌旁组织（P<0.05），且LINC00997高表达组患者的OS及DFS显著低于LINC00997低表达组患者（P<0.01 或 P<0.05）。在 68例在GCA组织中，LINC00997的表达水平显著高于癌旁组织（P<0.01），其表达与患者淋巴结转移、TNM 分期及 OS相关联（P<0.05或P<0.01）。敲减LINC00997的 SGC7901 细胞的迁移和侵袭能力均显著降低（均 P<0.01），细胞中E-cadherin的表达显著升高，N-cadherin、vimentin的表达均显著降低（P<0.05或P<0.01）。 结论： LINC00997在GCA组织和胃癌细胞中高表达，其高表达可能促进了胃癌细胞的迁移、侵袭及EMT进程，有望成为GCA患者预后评估的分子标志物。

Objective: To detect the expression of LINC00997 in gastric cardia adenocarcinoma (GCA) tissues and gastric cancer cells and analyze its relationship with the clinicopathological features and prognosis of GCA patients, as well as to explore the effect of LINC00997 knockdown on the migration, invasion and epithelial-mesenchymal transition (EMT) of SGC7901 cells. Methods: Based on the TCGA and GTEx database, the expression of LINC00997 in gastric cancer tissues and its relationship with the prognosis of gastric cancer patients were analyzed. qPCR was applied to detect the expression of LINC00997 in 68 pairs of GCA tissues and the corresponding para-cancerous tissues and gastric cancer cells. The association between its expression level and clinicopathological characteristics and prognosis of patients was also analyzed. The effects of LINC00997 knockdown on migration and invasion of gastric cancer SGC7901 cells were examined by Wound-healing assay and Transwell invasion assay, respectively. The effects of LINC00997 knockdown on the expression of EMT-related markers E-cadherin, N-cadherin and vimentin were detected by qPCR and WB methods. Results: The expression of LINC00997 in gastric cancer tissues was significantly higher than that in para-cancerous tissues (P<0.05), and the overall survival (OS) rate and disease-free survival (DFS) rate of the LINC00997 high expression group was significantly lower than that of the low expression group (P<0.05 or P<0.01). The expression of LINC00997 in 68 GCA tissues was significantly higher than that in corresponding para-cancerous tissues (P<0.01), and was correlated with lymph node metastasis, TNM stage and OS of the patients (P<0.05 or P<0.01). The migration and invasion of SGC7901 cells with LINC00997 knockdown were significantly suppressed (all P<0.01), the expression levels of N-cadherin and vimentin were decreased while the expression of E-cadherin was increased (P<0.05 or P<0.01). Conclusion: LINC00997 is highly expressed in GCA tissues and cells. The high expression of LINC00997 may promote the migration, invasion and EMT process of GCA, and is expected to become a candidate molecular marker for prognostic evaluation of patients with GCA.

R735.2; R730.2; R730.7

国家自然科学基金资助项目（No.81572441）；河北省医学科学研究重点课题资助项目（No.20201050）