The Role Of RECK Methylation In Gastric Cancer And Its Clinical Significance

ObjectiveGastric cancer is one of the most common malignancies in the world, particularly in Eastern Asian countries such as China, Korea, and Japan. Despite the advance in diagnosis and treatment, the prognosis for advanced gastric cancer is poor, with a 5-year survival rate about 20%-30%. Over the past years, many evidences have clearly demonstrated that multiple genetic alterations are responsible for the development and progression of gastric cancerThe RECK gene were newly discovered by Takahashi et al in 1998, which has been identified on chromosome region 9p13-p12 and encodes a membrane-anchored glucose protein with a relative molecular mass of 110000. The RECK protein is an important mediator of tissue remodeling to inhibit MMPs, post-transcriptionally. Through negatively regulated MMPs, RECK protein limits tumor invasion and metastasis and angiogenesis.Since not much is known about the relationship between RECK and gastric cancer, the purpose of this study is to investigate the relationship between RECK methylation and clinicopathological characteristics of gastric cancer and evaluate the role of RECK methylation in peritoneal irrigation fluid in detecting peritoneal metastases.MehtodsThe methylation status of RECK gene in forty paired gastric cancer specimens, the corresponding adjacent normal mucosa, lymph nodes and peritoneal irrigation fluid was investigated by methylation-spcific polymerase chain reaction(MS-PCR). ResultsAberrant methylation of RECK gene was detected in 27.5%(11/40) of the adjacent normal mucosa,47.5%(19/40) of gastric cancer specimens,57.1%(12/21) of the lymph nodes, and 35%(14/40) of peritoneal irrigation fluid, and there were significant differences between the adjacent normal mucosa and the lymph nodes (P=0. 023). Presence of RECK methylation in the primary tumor was significantly correlated with tumor invasion (P=0.023). The accuracy of RECK methylation in peritoneal lavage fluid for diagnosing peritoneal metastasis was of 72.5%(26/40), with sensitivity 66.7%(6/9), specificity 74.2%(23/31).ConclusionsAberrant methylation of RECK gene is a common event in the occurrence and progression of gastric carcinoma,which may provide useful information for the early diagnosis of peritoneal metastases and a new therapy for gastric cancer.