Luo Yunzhao, Cao Heng, Lei Chuqi, Liu Jun
Department of Breast Surgery, Beijing Chaoyang Hospital of Capital Medical University, No. 8 Workers' Stadium South Road, Beijing, 100020, China.
Department of Breast Surgery, Cancer Institute and Hospital, Chinese Academy of Medical Sciences, Beijing, 100021, China.
Genes Genomics. 2023 Nov;45(11):1367-1376. doi: 10.1007/s13258-023-01445-y. Epub 2023 Sep 25.
A specific sialyl-transferases called ST6GALNAC1 has been proven to up-regulate abnormal O-glycosylation, which is strongly associated with tumorigenesis and cancer progression. However, the precise pathological outcome of ST6GALNAC1 expression in breast cancer cells remains unknown. Therefore, our study aims to investigate the functional role of ST6GALNAC1 and its impact on the epithelial-mesenchymal transition (EMT) pathway in breast cancer cells.
Plasmids with siRNA were used to construct ST6GALNAC1 knockoff (si-ST6GALNAC1) MDA-MB-231 and MDA-MB-453 cells, while lentiviruses were used to construct ST6GALNAC1 over-expression (oe-ST6GALNAC1) MCF-7 and BT474 cells. Transfer efficiency was verified by Western Blot. Then we selected transfected cells and assessed the changes in cell proliferation, invasion, migration, and EMT markers.
The expression of ST6GALNAC1 significantly enhanced cell migration and invasion, which was confirmed by Wound Scratch Assay and Transwell Assay. Particularly, ST6GALNAC1 expression directly induced the EMT signaling pathway. E-cadherin was markedly decreased in oe-ST6GALNAC1 cells, accompanied by an up-regulation of mesenchymal markers including N-cadherin, snail, and ZEB1. However, no significant correlation was found between ST6GALNAC1 expression and cell proliferation. All of the outcomes were reversely validated in si-ST6GALNAC1 cells.
The expression of ST6GALNAC1 promotes cell migration and invasion probably by triggering the molecular process of the EMT pathway in breast cancer cells, which may provide new clues for designing novel molecular targeted drugs in breast cancer treatment.
一种名为ST6GALNAC1的特定唾液酸转移酶已被证明可上调异常O-糖基化，这与肿瘤发生和癌症进展密切相关。然而，ST6GALNAC1在乳腺癌细胞中的精确病理结果仍不清楚。因此，我们的研究旨在探讨ST6GALNAC1的功能作用及其对乳腺癌细胞上皮-间质转化（EMT）途径的影响。
使用带有小干扰RNA（siRNA）的质粒构建ST6GALNAC1敲除（si-ST6GALNAC1）的MDA-MB-231和MDA-MB-453细胞，同时使用慢病毒构建ST6GALNAC1过表达（oe-ST6GALNAC1）的MCF-7和BT474细胞。通过蛋白质免疫印迹法验证转染效率。然后我们选择转染后的细胞并评估细胞增殖、侵袭、迁移和EMT标志物的变化。
通过伤口划痕试验和Transwell试验证实，ST6GALNAC1的表达显著增强了细胞迁移和侵袭能力。特别是，ST6GALNAC1的表达直接诱导了EMT信号通路。在oe-ST6GALNAC1细胞中，E-钙黏蛋白明显减少，同时间充质标志物包括N-钙黏蛋白、蜗牛蛋白和锌指蛋白E盒结合蛋白1（ZEB1）上调。然而，未发现ST6GALNAC1表达与细胞增殖之间存在显著相关性。所有结果在si-ST6GALNAC1细胞中得到反向验证。
ST6GALNAC1的表达可能通过触发乳腺癌细胞中EMT途径的分子过程来促进细胞迁移和侵袭，这可能为乳腺癌治疗中设计新型分子靶向药物提供新线索。
