Study On The Integration Site Of CfDNA HBV In Liver Cancer

Hepatocellular carcinoma(HCC)is a a high incidence tumor,About 300 thousand people died each year which is cause by it in our country,hepatitis B virus(HBV)s the main culprit in causing it.During the HBV infecting,HBV integrates into the DNA genome,influencing the function of integration sites around it,destroying or promoting gene expression of cell growth and differentiation,in order to prompting the malignant transformation of liver cells.The previous studies on the integration of HBV mainly aimed at primary tumor,however,it’s not practical to conduct multiple biopsies on the primary tumor,which is difficult in both ethics and practical operation.It will not only increase the pain of patient and costs of medical,but also delay the treatment and lead to complications.Our study aimed to find out the difference of HBV integration sites in circulating free DNA of liver cancer patients at different stages,to provide the change of HBV integration for the auxiliary diagnosis and monitoring of liver cancer,efficacy tracking and prognosis judgement.We collected 20 swatchs of the normal people and patients with chronic hepatitis b,cirrhosis and HCC,extracting the cfDNA and detecting HBV integration sites by Alu-PCR method,different genotypes of HBV integration sites was analyzed by highthroughput sequencing technology,to conclude different period patients’ HBV integration sites in the genome.We successfully established variety of fast,cheap,and the diverse analyzed method of DNA pretreatment and integration sites analyzed,hepatitis b virus integration events in the host cell was detected.There is no integration in normal human genome,16 of them were found in the chronic hepatitis b group,and14 cases in live cirrhosis group,however,in the liver cancer group,only 1 case was found to be integrated.In the whole HBV gene fragment,the most easily to integrate is the x fragment,the second is the core fragment,and there is no integration about the S fragment.It is concluded that HBV integration is closely related to the occurrence of HCC.Many cases of HBV integration in patients with chronic hepatitis B and cirrhosis,and the Genetic instability after integration make it difficult to detect HBV integration in patients with liver cancer.