Correlation Between Codeletion of Chromosome 1p/19q and MGMT Promoter Methylation in Oligodendrogliomas

Objective To explore the relationship between chromosome 1p/19q codeletion and MGMT promoter methylation in oligodendrogliomas.

Methods We collected 35 cases of oligodendroglioma and 32 cases of anaplastic oligodendroglioma tissue specimens as the experimental group, and 20 cases of astrocytomas and 20 cases of normal brain tissue specimens as the control group. Fluorescence in situ hybridization (FISH) was used to detect the chromosome 1p/19q codeletion, and the methylation status of MGMT promoter was analyzed by methylation-specific PCR (MSP).

Results The frequencies of the 1p/19q codeletion in oligodendrogliomas and anaplastic oligodendrogliomas were 85.71% and 75% respectively, which were significantly higher than those in astrocytomas and normal brain tissues(P < 0.05). The frequencies of the MGMT promoter methylation in oligodendrogliomas, anaplastic oligodendrogliomas and astrocytomas were significantly higher than those in normal brain tissues(P < 0.05), but there was no statistical difference among each other(P > 0.05). The Spearman correlation analysis showed that the 1p/19q codeletion was positively correlated with the MGMT promoter methylation in oligodendrogliomas. Both 1p/19q codeletion and MGMT promoter methylation were correlated with the 3-year survival rate(P < 0.05).

Conclusion 1p/19q codeletion is closely linked with MGMT promoter methylation in oligodendrogliomas, therefore, the combined detection of these two biomarkers may be helpful for diagnosis and evaluating the prognosis.