Detection of MLH1 Methylation in Glioma using Methylation-Sensitive High Resolution Melting (MS-HRM)

Abstract

Loss of expression of MLH1 gene has been associated with disruption on mismatch repair (MMR) mechanism. Defect in this mechanism is tightly correlated with the tumorigenesis of several types of cancer. Hypermethylation of MLH1 gene promoter is one of the cause in lack of expression of MLH1 protein. This mechanism is suspected to be involved in gliomagenesis, just like how it is known in colorectal cancer development. Unfortunately, study on hypermethylation status of MLH1 gene promoter in glioma is very limited, especially in Indonesia. Methylation-sensitive high resolution melting (MS-HRM) PCR based procedure is used to evaluate methylation status of MLH1 gene from glioma. This study found hypermethylation of the MLH1 promoter in 33% of glioma samples from Indonesia. From the finding, only 1 out of 4 methylated MLH1 promoters showed loss of expression of the MLH1 protein.