Institute of Genetic Medicine, Newcastle University, Newcastle-upon-Tyne NE1 3BZ, UK.
Int J Mol Sci. 2016 Feb 24;17(3):275. doi: 10.3390/ijms17030275.
Activation of an aberrant glycosylation pathway in cancer cells can lead to expression of the onco-foetal sialyl-Tn (sTn) antigen. STn is a truncated O-glycan containing a sialic acid α-2,6 linked to GalNAc α-O-Ser/Thr and is linked with an adverse outcome and poor prognosis in cancer patients. The biosynthesis of the sTn antigen has been linked to the expression of the sialytransferase ST6GalNAc1, and also to mutations in and loss of heterozygosity of the COSMC gene. sTn neo- or over-expression occurs in many types of epithelial cancer including gastric, colon, breast, lung, oesophageal, prostate and endometrial cancer. sTn is believed to be carried by a variety of glycoproteins and may influence protein function and be involved in tumour development. This review discusses how the role of sTn in cancer development and tumour cell invasiveness might be organ specific and occur through different mechanisms depending on each cancer type or subtype. As the sTn-antigen is expressed early in carcinogenesis targeting sTn in cancer may enable the targeting of tumours from the earliest stage.
在癌细胞中，异常糖基化途径的激活可导致肿瘤胚胎性唾液酸化 Tn（sTn）抗原的表达。sTn 是一种截断的 O-聚糖，含有一个通过 α-2,6 键连接到 GalNAc α-O-Ser/Thr 的唾液酸，并且与癌症患者的不良结局和预后不良相关。sTn 抗原的生物合成与唾液酸转移酶 ST6GalNAc1 的表达有关，也与 COSMC 基因的突变和杂合性丢失有关。sTn 新表达或过表达发生在许多上皮性癌症中，包括胃癌、结肠癌、乳腺癌、肺癌、食管癌、前列腺癌和子宫内膜癌。sTn 被认为由多种糖蛋白携带，并可能影响蛋白质功能并参与肿瘤发生。本文综述了 sTn 在癌症发展和肿瘤细胞侵袭中的作用可能具有器官特异性，并根据每种癌症类型或亚型通过不同的机制发生。由于 sTn 抗原在癌变早期表达，因此针对癌症中的 sTn 可能能够从最早阶段靶向肿瘤。
