Background: Embryonic stem cell expressed Ras (ERas) oncogene is associated with the tumorigenicity of embryonic stem cells. The aim of this study was to clarify the significance of ERas expression in clinical samples of gastric carcinomas.
Materials and methods: Three hundred and few tissues from gastric cancer patients were analyzed by immunohistochemical techniques using an anti-ERas antibody. ERas mRNA expression in 77 gastric carcinomas was examined by reverse-transcription polymerase chain reaction.
Results: ERas expression was positive in 135 (44%) of 304 gastric carcinomas. ERas-positive expression had a significant relationship with invasion depth (p<0.01), histological type (p<0.01), clinical stage (p=0.013) and curability (p=0.001). Prognosis of ERas-negative patients was significantly (p=0.029) poorer than that of ERas-positive patients, while ERas was not an independent prognostic factor. Expression of ERas mRNA was found in 35 (45%) out of 77 gastric cancer tissues.
Conclusion: ERas oncogene is associated with the tumorigenic process of human gastric carcinomas.