Immunohistochemical expression of core 2 β1,6‐ N ‐acetylglucosaminyl transferase 1 ( C 2 G n T 1) in endometrioid‐type endometrial carcinoma: a novel potential prognostic factor

Aims It has been reported that the expression of core 2 β1,6‐ N ‐acetylglucosaminyl transferase 1 ( C 2 G n T 1), which synthesizes the core 2 branching structure on O ‐glycans, may be associated with the biological aggressiveness of tumour cells. Therefore, the aim of this study was to examine the relationship between the expression of C 2 G n T 1 and clinicopathological parameters of patients with endometrial carcinoma. Methods and results The immunohistochemical expression of C 2 G n T 1 was examined in 84 cases of endometrioid‐type endometrial carcinoma, 15 cases of endometrial hyperplasia, and 30 normal endometria. The staining intensity was reported according to a positivity index ( PI , full score 100), calculated from the percentage of positive cells. The expression of C 2 G n T 1 was significantly higher in endometrial carcinoma ( PI  = 8.31 ± 15.29) than in normal endometrium ( PI  = 0.52 ± 1.24) ( P  < 0.0005). In carcinomas, the PI was higher in high‐grade or advanced‐stage tumours, but not significantly. Topologically, C 2 G n T 1 was strongly expressed at sites of deep myometrial invasion. In addition, patients with C 2 G n T 1 overexpression ( PI  ≥ 10) had significantly shorter survival ( P  < 0.0005). Multivariable analysis also indicated that C 2 G n T 1 overexpression was an independent prognostic factor ( P  = 0.017). Conclusions C 2 G n T 1 appears to be involved in the biological aggressiveness of endometrial carcinoma. C 2 G n T 1 might become a novel prognostic factor for endometrial carcinoma.