Purpose: To investigate the expression patterns of N-acetyl galactosamine transferases (GalNAc-Ts)-3 and GalNAc-T6 in clinicopathologically characterized endometriosis (EMS), and to explore their clinical significance.
Methods: Ectopic and eutopic endometrial tissue samples were obtained and confirmed with CD-10 immunohistochemistry in patients with EMS (n = 12), whereas normal control endometrium was obtained from patients with uterine septum (n = 12). The mRNA and protein levels of GalNAc-T3 and GalNAc-T6 were detected in these samples using quantitative real-time PCR, immunohistochemistry, and western blotting.
Results: GalNAc-T3 and GalNAc-T6 were expressed in the endometrium of all groups, with no significant changes observed during the menstrual cycle. The expression of GalNAc-T3 and GalNAc-T6 in ectopic endometrium was significantly lower than that in eutopic (P < 0.05) or control endometrium (P < 0.05), whereas there were no significant differences (P > 0.05) between eutopic and control endometria. Furthermore, the expression of GalNAc-T3 and GalNAc-T6 was significantly lower in patients with stage III/IV EMS compared to patients with stage I/II (P < 0.05).
Conclusions: Both GalNAc-T3 and GalNAc-T6 expression levels were downregulated in ectopic endometrium, which may increase the adhesion and invasion of endometrial cells and contribute to the development of EMS. Moreover, we found a strong correlation between the expression of GalNAc-T3 and GalNAc-T6 and different stages of EMS.
Keywords: Adhesion; Endometriosis; GalNAc-T3; GalNAc-T6; Invasion.