Previous studies on brain tumors have been performed on the nuclear genome, but limited studies have been reported on the mitochondrial genome. The mitochondrial sirtuin (SIRT3/SIRT4/SIRT5) has been mutated in different cancers. Limited studies have been performed on brain tumors. Isocitrate dehydrogenase (IDH) is an important marker, and polymorphism in the IDH gene has been reported to differentiate the brain tumor subtypes. The present study was designed to screen mitochondrial sirtuins and IDH polymorphisms in brain tumor patients. One thousand blood samples were collected (500 brain tumor patients and 500 controls). Two SNPs for each gene SIRT3 (rs12226697, rs570591), SIRT4 (rs184496260, 1925909), SIRT5 (rs2841522, rs2841523), and one SNP for IDH (rs11554137) was screened using Tetra-ARMS PCR. Logistic regression showed that the mutant genotype of selected SNPs was associated with increased disease incidence compared to wild type. Haplotype analysis and linkage disequilibrium (LD) showed a strong LD in brain tumor patients. Kaplan-Meier analysis showed that mutant allele frequency was found to be associated with a significant decrease in the survival of brain tumor patients. The present study showed that the mutant allele of selected mitochondrial sirtuins' SNP was associated with increased brain tumor risk.
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