The lower expression of gonadotropin-releasing hormone receptor associated with poor prognosis in gastric cancer.

AimsExpression of gonadotropin-releasing hormone receptor (GnRHR) has been demonstrated in a number of malignancies. The aim is to investigate the expression of GnRHR and prognosis in gastric cancer.Methods and materialsGnRHR mRNA was examined in tumor and non-tumor tissues from 48 gastric cancer patients by Real-time PCR. The GnRHR protein expression was performed by immunohistochemical analysis.ResultsThe expression of GnRHR mRNA was higher (mean ± SD, -10.06 ± 1.28) in gastric tumor tissues than matched non-tumor tissues (mean ± SD, -12.43 ± 1.33). GnRHR mRNA expression was associated with lymph node metastasis, distant metastasis, and TNM stage. We found the decreased expression of GnRHR mRNA were significantly correlated with poor overall survival (P = 0.003). Immunocytochemical staining of GnRHR in tumor tissues showed mainly weak staining (43.48%, 10/23) and moderate staining (21.74%, 5/23) in high GnRHR mRNA patients, and mainly negative staining in low GnRHR mRNA patients. And the staining of GnRHR was not detection in tumor tissues for more than half of gastric patients (52.08%, 25/48). These results implied that the loss of GnRHR protein could be a main event in gastric cancer.ConclusionThe GnRHR expression is very low in gastric cancer, and the loss of GnRHR expression could be a poor prognostic factor, which implied that GnRHR could play an important role in the development of gastric cancer.