Expression Rate and PAX5 Gene Methylation in the Blood of People Suffering from Gastric Cancer

BACKGROUND: Gastric cancer is one of the most important health issues in the world. Considering the lack of plenty of pre-awarenesses, the survival of gastric cancer is still quite disappointing. Methylation of PAX5 gene promoter is observed in most cancer cells of a human. A study has shown that PAX5 is a new tumoral suppressor in gastric cancer and methylation of the PAX5 promoter is associated with the survival rate of gastric cancer. AIM: The present research seeks to study the expression rate and methylation of the PAX5 gene in the blood of patients who have gastric cancer to be used as a biomarker in this type of cancer. MATERIAL AND METHODS: Real-time PCR technique was used to assess expression of PAX5 gene, while the methylation status of PAX5 gene promoter in the blood samples of people who have gastric cancer versus blood samples obtained from normal Iranian population was studied using MS PCR technique. RESULTS: The final results pointed to the fact that expression of PAX5 in blood samples obtained from those who have gastric cancer is much less than what is observed in normal blood samples. A significant correlation was also observed between expression of this gene and age and promoter methylation rate. The results of methylation also indicated that 28% of PAX5 gene promoters among patients were methylated, while all normal samples were non-methylated. CONCLUSION: Studying the decrease observed in PAX5 gene expression and the rise in promoter methylation can be utilised as a biomarker to enhance pre-awareness of gastric cancer.