OBJECTIVE This study aimed to analyze the function of metastasis suppressor 1 (MTSS1) in triple negative breast cancer (TNBC). METHODS MTSS1 expression in 30 TNBC and paracancerous tissues was measured by quantitative reverse transcriptase polymerase chain reaction. The prognostic value of MTSS1 was assessed by Kaplan-Meier analysis followed by the log-rank test. MCF7 cells were transfected with si-MTSS1, while MDA-MB-231 cells were transfected with pcDNA3.1-MTSS1. Cell proliferation assay and transwell assay were performed to investigate the effects of MTSS1 on the biological behavior of breast cancer cells. Immunofluorescence and western blot were used to detect the influence of MTSS1 on epithelial-mesenchymal transition (EMT) markers. RESULTS MTSS1 expression was significantly lower in TNBC tissues compared with that in paracancerous tissues (0.012 vs. 0.370; P = 0.006). A lower MTSS1 expression level was also found in tumor tissues of patients with lymph node metastasis (P = 0.002) or tumor node metastasis stage (P = 0.010). Patients with low expression of MTSS1 (⩽ 0.009) had shorter disease-free survival (47.4 vs. 56.0 months; P = 0.012). The knockdown of MTSS1 in MCF7 cells inhibited cell proliferation, enhanced cell migration and invasion capacities, decreased the E-cadherin level, and increased the vimentin level, whereas overexpression of MTSS1 in MDA-MB-231 cells had the opposite effects (P < 0.05). CONCLUSIONS Our findings demonstrated that MTSS1 regulates proliferation, invasion, migration, and EMT in TNBC, and that decreased MTSS1 is associated with shorter disease-free survival.

中文翻译：

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转移抑制因子 1 通过抑制三阴性乳腺癌的上皮间质转化而发挥肿瘤抑制作用。

目的本研究旨在分析转移抑制因子1（MTSS1）在三阴性乳腺癌（TNBC）中的作用。方法通过定量逆转录聚合酶链反应测定30个TNBC和癌旁组织中MTSS1的表达。通过 Kaplan-Meier 分析和对数秩检验评估 MTSS1 的预后价值。用si-MTSS1转染MCF7细胞，用pcDNA3.1-MTSS1转染MDA-MB-231细胞。进行细胞增殖试验和transwell试验以研究MTSS1对乳腺癌细胞生物学行为的影响。免疫荧光和蛋白质印迹用于检测 MTSS1 对上皮间质转化 (EMT) 标志物的影响。结果 与癌旁组织相比，TNBC 组织中的 MTSS1 表达显着降低（0.012 对 0.370；P = 0.006）。在淋巴结转移（P = 0.002）或肿瘤淋巴结转移阶段（P = 0.010）的患者的肿瘤组织中也发现了较低的MTSS1表达水平。MTSS1 低表达（⩽ 0.009）的患者无病生存期较短（47.4 个月对 56.0 个月；P = 0.012）。MCF7细胞中MTSS1的敲低抑制细胞增殖，增强细胞迁移和侵袭能力，降低E-cadherin水平，增加波形蛋白水平，而MTSS1在MDA-MB-231细胞中的过表达具有相反的作用（P < 0.05 ）。结论 我们的研究结果表明 MTSS1 调节 TNBC 中的增殖、侵袭、迁移和 EMT，