Analysis of promotor methylation in miR137 gene for early detection of colorectal tumors in stool of patients with colorectal cancer.

Abstract

Genes involved in the cell cycle , apoptosis and the cell immigration have an important role in the colorectal cancer carcinogenesis process. Evaluation of methylation of genes involved in cancer has emerged as a reliable factor in the diagnosis of various cancers and has been suggested as a predictive, preventive and valuable factor in all human cancers, especially colorectal cancer. The aim of the present study was to investigate one of the major genes involved in colorectal cancer in northwestern Iran. Colorectal cancer is one of the most common cancers in all over the world. Annually approximately half of a million people struggle with this cancer. This disease is the second cause of cancers’ mortality in the world. In th United States it is the second cause of cancers’s mortality after lung cancer. Material and methods : In current study methylation of miR-137 was investigated in 40 patiants and 40 healthy control via ms-PCR methods. After DNA extraction, the samples were combined with sodium bisulphate, the method used to eliminate the unmethylated cytosines. In our study , msPCR were done with 2 primers on the samples, primer M and U, reaction with the primer M shows the methylation in the gene of this miR and the reaction with primer U shows no methylation. Reaction with both of primers shows partial methylation in the target gene. Differences of methylation between two groups were analysed with statistical tests. P.Values less than 0.05 were significant. Results : In the present study, among the 40 samples examined for the methylation rate of the target gene in 80 healthy and tumor samples, the methylation rate at the promoter site of the miR-137 gene in the tumor sample was significantly higher than that of the normal samples. And differences between the two groups of our study was significant.