Compartmentalized evolution of hepatitis B virus contributes differently to the prognosis of hepatocellular carcinoma

Serum hepatitis B virus (HBV) mutations can predict hepatocellular carcinoma (HCC) occurrence. We aimed to clarify if HBV evolves synchronously in the sera, adjacent liver, and tumors and predict HCC prognosis equally. A total of 203 HBV-positive HCC patients with radical hepatectomy in Shanghai, China during 2011-2015 were enrolled in this prospective study. Quasispecies complexity (QC) in HBV core promoter region was assessed using clone-based sequencing. We performed RNA-sequencing on tumors and paired adjacent tissues of another 15 HCC patients and analyzed it with 3 public datasets containing 127 samples. HBV QC was positively correlated to APOBEC3s’ expression level (r=0.28, p<0.001), higher in the adjacent tissues than in the tumors (p=6.50e-3), and higher in early tumors than in advanced tumors (p=0.039). The evolutionary distance between the sera-derived HBV strains and the tumor-derived ones was significantly longer than that between the sera-derived ones and the adjacent tissue-derived ones (p<0.001). Multivariate Cox regression analyses indicated that high HBV QC in the sera predicted an unfavorable overall survival (OS) (p=0.002) and recurrence-free survival (RFS) (p=0.004) in HCC; whereas it in the tumors predicted a favorable RFS (p<0.001), respectively. APOBECs-related HBV mutations including G1764A were more frequent in the sera than in the adjacent tissues. High-frequent A1762T/G1764A in the sera predicted an unfavorable RFS (p<0.001); whereas it in the tumors predicted a favorable RFS (p=0.035). In conclusion, HBV evolves more advanced in the sera than in the tumors. HBV QC and A1762T/G1764A in the sera and tumors have contrary prognostic effects in HCC.