Genetic variations of mitochondrial genome modify risk and prognosis of hepatocellular carcinoma patients.

BACKGROUND

Previous studies have indicated that mitochondrial genetic variations were associated with the risk of many cancers. However, there are few reports on the association between single nucleotide polymorphisms (SNPs) or haplogroups of mitochondrial DNA (mtDNA) and the risk or prognosis of hepatocellular carcinoma (HCC).

METHODS

In order to investigate the predictive and prognostic role of mtDNA SNPs and haplogroups in HCC, the mitochondrial genome of 188 HCC patients and 344 healthy controls were sequenced by next generation sequencing technology. Then, logistic regression analysis was used to determine the effect of mtDNA SNP or haplogroup on risk and prognosis of HCC patients.

RESULTS

The haplogroup M7 had an odds ratio (OR) of 0.47 (95% CI=0.24-0.91; P=0.026) to develop HCC. The frequency of 152T/C, 199T/C, 4048G/A, 9824T/C, 15784T/C, 16185C/T and 16399A/G was significantly different between HCC patients and the controls. In addition, multivariate analysis with COX hazards model showed that the patients with haplogroup M8 had lower survival rate than the patients with haplogroup D4 (HR=2.62, 95% CI=1.03-6.68; P=0.044). Three SNPs 15784T/C, 16185C/T and 16399A/G were also identified to have a statistically significant association with postoperative survival in HCC.

CONCLUSIONS

To date, these results provide the first evidence that mtDNA SNPs and haplogroups may be potential risk factors for susceptibility and survival of HCC patients.