目的：探讨鞘磷脂合成酶2（SMS2）是否通过Wnt/β-catenin 信号通路调控卵巢癌（OC）TOV-21G细胞增殖、迁移、侵袭、凋亡及其机制。方法：收集武汉市第三医院2022 年7月至2023 年5月间确诊的21 例OC患者的癌及癌旁组织标本，免疫组化法检测OC组织SMS2 表达水平。体外培养TOV-21G细胞，将细胞分为对照组、shRNA 慢病毒阴性对照组（sh-NC 组）、SMS2 shRNA 慢病毒组（sh-SMS2组）、Wnt/β-catenin 通路激活剂组LiCl（LiCl 组）和sh-SMS2+LiCl 组。Edu 染色法、Transwell 法、流式细胞术分别检测各组细胞的增殖、迁移和侵袭能力及凋亡水平，WB 法检测细胞中SMS2、Ki67、cyclin D1、BAX、c-caspase3、Bcl-2及Wnt/β-catenin 通路蛋白（β-catenin、c-Myc、MMP-9）的表达。构建TOV-21G细胞裸鼠移植瘤模型，观察敲低SMS2对移植瘤生长和SMS2、β-catenin 表达的影响。结果：与癌旁组织比较，OC组织中SMS2呈高表达（P<0.01）。转染sh-SMS2后，TOV-21G细胞中SMS2表达水平显著降低（P<0.05），细胞的增殖、迁移和侵袭能力及Bcl-2、β-catenin、c-Myc、MMP-9 蛋白表达均显著降低（均P<0.05），细胞凋亡率、BAX、c-caspase3 蛋白表达均显著升高（均P<0.05）；LiCl 处理能逆转敲低SMS2 对TOV-21G细胞增殖、迁移和侵袭及Wnt/β-catenin 通路的抑制作用（均P<0.05）。体内成瘤实验显示，敲低 SMS2 抑制裸鼠移植瘤的生长及SMS2、β-catenin 蛋白的表达（均P<0.05）。结论：敲低SMS2表达通过Wnt/β-catenin 信号通路抑制OC TOV-21G细胞的增殖、迁移、侵袭并促进细胞凋亡，同时LiCl处理则能逆转敲低SMS2对TOV-21G细胞增殖、迁移和侵袭的抑制作用。

Objective: To investigate whether sphingomyelin synthase 2 (SMS2) regulates the proliferation, migration, invasion and apoptosis of ovarian cancer (OC) TOV-21G cells through Wnt/β -catenin pathway and its mechanism. Methods: The cancer and para-cancerous tissue samples of 21 OC patients diagnosed in the Third Hospital of Wuhan from July 2022 to May 2023 were collected, and the SMS2 expression in the collected tissues was detected by immunohistochemistry. TOV-21G cells were cultured in vitro and grouped into control group, shRNA lentivirus negative control group (sh-NC group), SMS2 shRNA lentivirus group (sh-SMS2 group), Wnt/β-catenin pathway activator LiCl group (LiCl group), and sh-SMS2+LiCl group. Edu staining, Transwell method and flow cytometry were used to detect the proliferation, migration, invasion, and apoptosis of cells in each group. WB assay was used to detect the expression of SMS2, Ki67, cyclin D1, BAX, c-caspase3, Bcl-2 and Wnt/β -catenin pathway-related proteins (β -catenin, c-Myc, MMP-9) in the cells of each group. A TOV-21G cell transplanted tumor model was established in nude mice to observe the effects of SMS2 knockdown on the growth of transplanted tumors and the expression of SMS2 and β-catenin. Results: Compared with the para-cancerous tissues, the expression of SMS2 in OC tissues was increased obviously (P<0.05). After transfection with sh-SMS2, the expression level of SMS2 in TOV-21G cells was decreased obviously (P<0.05), the proliferation, migration, and invasion abilities of TOV-21G cells as well as the protein expression of Bcl-2, β-catenin, c-Myc, and MMP-9 were decreased obviously (all P<0.05), and the cell apoptosis rate, the protein expression of BAX and c-caspase3 were obviously increased (all P<0.05). LiCl could reverse the inhibitory effects of SMS2 knockdown on the proliferation, migration, invasion, and Wnt/β -catenin pathway of TOV-21G cells (all P<0.05). In vivo tumor formation experiments showed that SMS2 knockdown inhibited tumor growth and the expression of SMS2 and β-catenin (all P<0.05). Conclusion: SMS2 knockdown inhibits the proliferation, migration and invasion and promotes apoptosis of OC TOV-21G cells through Wnt/β-catenin signaling pathway, while LiCl treatment can reverse the inhibitory effects of SMS2 knockdown on the proliferation, migration and invasion of TOV-21G cells.

武汉市卫生健康委员会医学科研项目（No. WX21Q22）