Abstract 1568: Detection of HBV-host junction DNA sequences in urine of patients with HBV-infected HCC

Abstract

Abstract Hepatitis B virus (HBV) related liver diseases often progresses from hepatitis to cirrhosis and eventually to hepatocellular carcinoma (HCC), which has a poor prognosis, mostly due to late detection. Chronic HBV infections are associated with >50% of HCC cases worldwide, and up to 90% of HBV-related HCCs (HBV-HCC) were found to contain integrated HBV DNA. During infection, HBV DNA integrates in the host chromosome at variables sites, generating a unique HBV-host junction sequence (HBV-JS) that can serve as a DNA finger print of an infected hepatocyte. During hepatocarcinogenesis, tumorigenic hepatocyte(s) undergo uncontrolled clonal expansion resulting in one to few particular HBV-JS's becoming dominant. Thus, we hypothesize that the appearance of expanded HBV-JS species is a marker of clonal expansion and can be a potential marker for early detection of HBV-HCC. A PCR-based enrichment assay and next generation sequencing (NGS) approach were developed for the HBV DR1-2 integration hotspot region to explore the feasibility of detecting HBV-JS's in the circulation (i.e. urine) of patients with HBV-HCC. HBV-HCC tissue DNA samples underwent library construction and were enriched for DNA containing the HBV DR1-2 sequences. Enriched DNA fragments were then cloned and sequenced, from which 5 HBV-JS's were discovered at Chr5 (hTERT promoter), Chr7 (AOAH intronic transcript 1), Chr12 (KCN2), Chr19 (miRNA 512-1,-2), and Chr22 (LARGE) in four patient samples. These sites were further confirmed in matched urine DNA samples by designing primers to amplify the HBV-JS. The NGS approach, which includes HBV-HCC (n = 18), HBV-hepatitis (n = 5), and HBV-cirrhosis (n = 8) urine samples to identify HBV-JS’s, is in progress. Overall, this would be the first study both to demonstrate unambiguous detection of HBV-JS's in the urine of HBV-HCC patients and to suggest the potential of detecting expanded HBV-JS species in urine as a marker for HBV-HCC screening. Furthermore, if successful, the high-throughput detection of HBV-JS's in urine by NGS offers a promising noninvasive HBV-HCC screening platform, as well as provides insight into the carcinogenic mechanisms of HBV DNA integration. Citation Format: Selena Lin, Benjamin Song, Evan Trauger, Malcolm Hoffman, Emilie Thompson, Rebecca Zhou, Surbhi Jain, Wei Song, Ying-Hsiu Su. Detection of HBV-host junction DNA sequences in urine of patients with HBV-infected HCC. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1568. doi:10.1158/1538-7445.AM2015-1568