Laboratorio de Biología Molecular y Virología, Centro de Investigación Biomédica de Oriente, Instituto Mexicano del Seguro Social, Km 4,5 Carretera Federal Atlixco-Metepec, C,P, 74360 Metepec, Puebla, México.
Diagn Pathol. 2010 Nov 22;5:74. doi: 10.1186/1746-1596-5-74.
Altered sialylation has been observed during oncogenic transformation. Sialylated oligosaccharides of glycoproteins and glycolipids have been implicated in tumor progression and metastases. In the cervical cancer high levels of sialic acid have been reported in the patients serum, and an increased of total sialic acid concentration has been reported for the cervical neoplasia and cervical cancer. This study investigates the changes in expression and distribution of α2,3-linked sialic acid and α2,6- linked sialic acid in low and high squamous intraepithelial lesions and in normal tissue.
Lectin histochemistry was used to examine the expression and distribution of sialic acid in different grades of cervical neoplasia. We applied Maackia amurensis lectin, which interacts with α2,3-linked sialic acid and Sambucus nigra lectin specific for α2,6-linked sialic acid.
The histochemical analysis showed that α2,3-linked sialic acid and α2,6- linked sialic acid increased in intensity and distribution in concordance with the grade of squamous intraepithelial lesion (SIL). These results are in concordance with a previous study that reports increased RNAm levels of three sialyltransferases.
These results show that the change in sialylation occurs before cancer development and may play an important role in cellular transformation. These findings provide the basis for more detailed studies of the possible role of cell surface glycoconjugates bearing sialic acid in the cellular cervix transformation.
在致癌转化过程中观察到唾液酸化的改变。糖蛋白和糖脂的唾液酸化寡糖已被牵连到肿瘤进展和转移中。在宫颈癌中，患者血清中的唾液酸水平较高，宫颈上皮内瘤变和宫颈癌的总唾液酸浓度也有所增加。本研究调查了α2,3-连接的唾液酸和α2,6-连接的唾液酸在低级别和高级别鳞状上皮内病变以及正常组织中的表达和分布变化。
利用凝集素组织化学检测不同级别宫颈肿瘤中唾液酸的表达和分布。我们应用了与α2,3-连接的唾液酸相互作用的 Maackia amurensis 凝集素和特异性识别α2,6-连接的唾液酸的 Sambucus nigra 凝集素。
组织化学分析表明，α2,3-连接的唾液酸和α2,6-连接的唾液酸的强度和分布随着鳞状上皮内病变（SIL）程度的增加而增加。这些结果与先前的一项研究一致，该研究报告了三种唾液酸转移酶的 RNAm 水平增加。
这些结果表明唾液酸化的变化发生在癌症发展之前，可能在细胞转化中发挥重要作用。这些发现为更详细地研究细胞表面携带唾液酸的糖缀合物在宫颈细胞转化中的可能作用提供了基础。
