Quantitative detection of common deletion of mitochondrial DNA in hepatocellular carcinoma and hepatocellular nodular hyperplasia

AIM: To study the deletion of mitochondiral DNA in hepatocellular carcinoma and hepatocellular nodular hyperplasia and its significance in the development of cancer. METHODS: Deleted mtDNA (CD-mtDNA) and wild type mtDNA (WT-mtDNA) were quantitatively analyzed by using real-time PCR in 27 hepatocellular carcinomas (HCC) and corresponding noncancerous liver tissues and 27 hepatocellular nodular hyperplasiae (HNH). RESULTS: A novel CD (4 981 bp) was detected in 85% (23/27) and 83%(22/27) of HCC and HNH tumor tissues, respectively, which were significantly higher than that in paired noncancerous liver tissues (57%, 15/27) (P<0.05). The CD/WT-mtDNA ratio in HCC tumors was 0.00092 (median, interquartile range, 0.0001202-0.00105), which was significantly higher than that in paired noncancerous liver tissues (median, 0.000, quartile range, 0-0) (P=0.002, Mann-Whitney Test), and was 25 of times of that in HNH tissues (median, 0.0000374, quartile range, 0-0.0004225) (P=0.002, Mann-Whitney test). CONCLUSION: CD-mtDNA mutation plays an important role in the development and progression of HCC.