p14 ARF promoter region methylation as a marker for gliomas diagnosis

Methylation in the promoter region is one of the mechanisms through which tumor suppressors are inactivated, resulting in tumorigenesis and/or tumor progression. Herein, we studied the methylation status in the promoter region of the p14 ARF tumor suppressor gene in 33 brain tissues isolated from glioma patients (astrocytomas) and compared to 12 brain tissues isolated from autopsy donors using methylation-specific polymerase chain reaction (MSP). The correlation between the expression of P14 and P53 was investigated using immunohistochemistry (IHC). The average percentage of methylation in the promoter region of p14 ARF gene in brain samples from glioma patients is 39.4%, while 0 from autopsy donors. No difference in the methylation level between low-grade and high-grade gliomas was detected. The methylation status has no correlation with the prognosis in glioma patients. A significant correlation between the expression of mutant form of TP53 and the grade of the glioma was established. Furthermore, there was a negative correlation between methylation of the p14 ARF promoter and the expression of the mutant form of TP53. Therefore, our data suggest that methylation in the promoter region of the p14 ARF gene may be used as a biomarker for the diagnosis of gliomas.