Abstract 545: Detection of liver-derived hepatitis B virus-host junction sequences in urine of hepatitis B infected patients for noninvasive disease monitoring

Integrated hepatitis B virus (HBV) DNA detected in more than 85% of HBV-infected hepatocellular carcinoma (HBV-HCC) can cause insertional mutagenesis, chromosomal instability, sustained viral protein expression, and/or immune-mediated inflammation leading to HCC carcinogenesis. An opportunistic outcome of HBV DNA integration events, which occur randomly into the host genome, is the creation of a unique HBV-host junction sequence (HBV-JS) in individually infected hepatocytes representing a specific molecular signature of that cell. A noninvasive approach to detect HBV-JS's will enable frequent monitoring and aid in assessing HBV treatment efficacy and HCC disease progression. Here, we assessed the feasibility of detecting HBV-JS's in urine of HBV-infected patients as a proof-of-concept for utilizing urine as a noninvasive HBV-JS liquid biopsy for HBV-related disease monitoring. Utilizing an in-house developed HBV primer extension capture (PEC) NGS assay, we assessed early-stage HBV-patient tumor tissue and matched urine (n=8). Five of 8 urine samples contained detectable HCC tissue-derived HBV-JS's, including a TERT junction sequence. Next, we assessed 32 urine specimens collected from 28 HBV-infected patients including hepatitis (n=5), cirrhosis (n=11), HCC (n=4), and post-HCC (n=8). Interestingly, all urine samples contained HBV-JS sequences with 30 of 32 urines containing integrations in gene-coding regions. Of 351 unique HBV-JS in gene-coding regions identified in urine, 11 HBV-JS's have also been previously reported in tissue of HCC patients, including TERT. All eleven HBV-JS's were identified in cirrhosis or HCC patient cohorts. Furthermore, the distribution of urinary integrated HBV DNA in the HBV genome in all disease categories was found predominantly clustered in HBV DR1-2 (>70%), an integration hotspot, consistent with findings in tissue. Altogether this support the potential of urine as a noninvasive HBV-JS liquid biopsy to monitor HBV-infected patients for disease progression and treatment efficacy. Citation Format: Selena Lin, Yu-lan Kao, Robin Su, Ting-Tsung Chang, Yih-Jyh Lin, Yixiao Cui, Hie-Won Hann, Grace Park, Wei Song, Ying-Hsiu Su. Detection of liver-derived hepatitis B virus-host junction sequences in urine of hepatitis B infected patients for noninvasive disease monitoring [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 545.