CXCR7 genetic variant predicts treatment response of pegylated-interferon α in HBeAg-positive chronic hepatitis B patients

Objectives

CXC chemokine receptor 7 (CXCR7) plays pivotal roles in different virus infections. However, no research focused on the role of CXCR7 in hepatitis B virus (HBV)-infected patients. The primary aim of this study is to elucidate the role of CXCR7 in predicting the treatment response of chronic hepatitis B (CHB) patients undergoing pegylated interferon-alpha (PegIFNα) therapy.

Methods

Two cohorts with a total of 945 Chinese CHB patients (Cohort 1, n = 238; Cohort 2, n = 707) were enrolled in this retrospective study, all the patients were positive for hepatitis B e antigen (HBeAg) and received PegIFNα treatment for 48 weeks and followed-up for 24 weeks post-treatment. Nineteen tag single-nucleotide polymorphisms (SNPs) were selected within and surrounding the CXCR7 gene region. The associations of CXCR7 SNPs and polygenic score (PGS) with PegIFNα treatment response were investigated in the two cohorts.

Results

Among the 19 candidate SNPs of CXCR7, rs2952665 (A > G) was significantly associated with combined response (CR, defined as HBeAg seroconversion and HBV DNA level <3.3log₁₀IU/mL, P = 0.002) and hepatitis B surface antigen (HBsAg) decline (P = 0.015) in the two cohorts at week 72. Furthermore, a PGS comprising CXCR7_rs2952665 and five additional SNPs, which were previously recognized as biomarkers of PegIFNα treatment response, demonstrated a robust correlation with both CR (P = 1.38 × 10⁻¹²) and HBsAg decline (P = 0.003) in all the patients.

Conclusion

This research illustrated that CXCR7_rs2952665 is a promising predictor of the PegIFNα therapy efficiency in Chinese HBeAg-positive CHB patients. A PGS consisting of CXCR7_rs2952665 and five previously reported SNPs predicts treatment response to PegIFNα better.