ABSTRACT
Background and purpose:Colorectal cancer (CRC) is a malignancy which is the third incidence and the fourth mortality in the worldwide. The main reason for the development of CRC is that the changes of genetic and epigenetic causes the tumor suppressor gene methylation silencing. This study aimed to investigate the plasma and stool GATA5 gene promoter methylation was detected in clinical diagnosis of CRC. Methods: To collect the paired plasma and stool specimens of 34 cases of healthy and 43 cases of patients with CRC. Methylation speciifc PCR (MSP) was respectively detected the GATA5 gene methylation levels of GATA5 gene in plasma and stool. And then separately analyzed their correlations with clinical and pathological parameters in gastric carcinoma. Results: The result of MSP showed that GATA5 gene promoter methylation rates in plasma and stool of CRC patients were 60.74%, 76.60%, respectively, were higher than those of healthy persons (6.47%, 32.35%). And the differences were statistically signiifcant (P=0.006 7, P=0.000 2, respectively). GATA5 gene methylation rates in plasma of CRC patients were closely related to clinical stage (P=0.000 5) and lymph node metastasis(P=0.020), while GATA5 gene methylation rates in stool of CRC patients had no signiifcant with clinical and pathological parameters. Conclusion:Detection of faecal GATA5 gene methylation level and supplemented plasma GATA5 gene methylation level can become a simple, non-invasive, sensitive and speciifc method for clinical diagnosis of CRC.
ABSTRACT
Objective:To investigate the diagnostic value of the promoter methylation of plasma RNF180 gene and its protein ex-pression for the detection of gastric cancer. Methods:Methylation-specific polymerase-chain reaction (MSP) and enzyme-linked immu-no-sorbent assay (ELISA) were performed to detect DNA methylation and protein expression of the RNF180 gene, respectively. The correlations of DNA methylation and protein expression of the RNF180 gene with the clinico-pathological parameters of gastric carcino-ma were then separately analyzed. Results:MSP showed that the methylation rates of the RNF180 gene were 62.75%and 21.88%in the plasma of patients with gastric carcinoma and healthy volunteers, respectively;this result indicated that the two groups significantly differed (P0.05). Conclusion:The RNF180 gene is expressed at a hypermethylation rate, and the corresponding protein expression level is de-creased in the plasma of individuals with gastric carcinoma. Therefore, RNF180 gene methylation in plasma could be applied to detect microinvasion for the clinical diagnosis of gastric cancer.