Effect of MTHFR C677T Polymorphism on Methylation Status of E-Cadherin in Gastric Cancer

Abstract

Background: MTHFR gene is one of the main and effective factors in genes methylation. This gene has a common polymorphism in cordon 677, which can affect its activity. Changing activity rate of this gene can affect methylation rate of tumor suppressor genes and cell membrane proteins and other genes in addition to their expression rate. Therefore, it can be considered as one of the effective factors on producing cancer. Methods: In this descriptive-cross sectional study, 34 cancer and non-cancer tissue samples were studied. Initially, DNA was extracted from samples and then E-cadherin and MTHFR c677t polymorphism were amplified by the polymerase chain reaction (PCR). Methylation status of E-cadherin was evaluated by adding methylation restriction enzyme HpaII and polymorphism of MTHFR c677t was assessment by the restriction fragment length polymorphism (RFLP) method. Results: Methylation status of E-cadherin gene numbers of methylated cases in the cancer group were equal to one and unmethylated cases equal to 33 and numbers of unmethylated cases in the non-cancer group was equal to 34 while there were no methylated cases. In assessment of methylation status of E-cadherin and different genotypes of MTHFR in codon number 677 in cancer samples, number of CC, CT and TT genotypes were equal to 0, 1 and 0 in the methylated group and equal to 6, 27 and 1 in the unmethylated group, respectively. Conclusions: According to this observation, another factor such as oncogenes activity may cause cancer in samples but CT genotype of MTHFR can be considered as an effective factor in creating cancer.