Prognostic significance of Notch signalling molecules and their involvement in the invasiveness of endometrial carcinoma cells

Abstract

The aim of this study was to investigate the significance of the expression of Notch-related molecules in endometrial carcinoma. The expression of Notch receptors (Notch1 and 3) and Notch ligands [Jagged (JAG) 1 and Delta-like (DLL) 4] was examined immunohistochemically in 37 normal and 76 malignant endometrial tissue samples. For each section, immunohistochemical staining was scored using a positivity index (PI, full score; 200). The effects of a Notch inhibitor, DAPT, on cell proliferation, invasion and motility were investigated using endometrial carcinoma cell lines. The PIs for Notch1 (mean±SD 90.4±15.3), Notch3 (95.6 ± 20.4), JAG1 (95.5±10.0) and DLL4 (88.2±9.6), were significantly higher in endometrial carcinoma than normal endometrium. The PI for Notch1 was associated significantly with advanced International Federation of Gynecologists & Obstetricians (FIGO) stage. In addition, patients with tumours showing high expression of both Notch1 and JAG1 had a poor prognosis compared with those having double-negative carcinomas (P=0.015). DAPT suppressed invasiveness of cells derived from the endometrial carcinoma cell line KLE. The Notch1-JAG1 axis may enhance the invasive properties of endometrial carcinomas, which suggests the Notch pathway may be a promising target for the treatment of this malignancy.