Evaluating the expression and methylation of CDKN2A and CDK-4 and CDK-6 expression as its targets in tumoral and marginal tissues of colorectal cancer patients

Abstract

Colorectal cancer is one of the most common malignancies worldwide. CDK-4 and CDK-6 are two major regulators of the cell cycle, which play a significant role in stimulating the growth and division of cells at different checkpoints in the cell cycle, and considering their role in cellular processes, they are among the important cellular oncogenes. These two oncogenes are among the important targets of the CDKN2A gene and it seems that the changes in the expression and methylation of CDKN2A are related to the changes in the expression of CDK-4 and CDK-6. In this regard, in the present study, we aimed at investigating the change in the expression level of this CDK-4 and CDK-6 genes in the tissue samples of patients with colon cancer and their relationship with the CDKN2A tissue leves. Method: 75 patients with colorectal cancer were included in the study with their informed consent. The expression level of the desired genes was measured by Real Time PCR method. To check the methylation level of the studied gene, the samples were first extracted with a DNA kit, and after extraction, the samples were treated with a special methylation kit, and the methylation level of the desired region was evaluated by the msHRM method. Pvalue<0.05 was considered significant in statistical tests. Result: The expression level of all genes investigated in this research had significant changes between tumor and margin samples. On the other hand, an increased level of CDKN2A methylation was evident in tumor samples compared to marginal tissues. Also, these changes were related to some clinicopathological indicators of the patients including Lymph node metastasis, distant metastasis and disease stage.