Gene polymorphisms of interleukin-28, p21-activated protein kinases 4, and response to interferon-α based therapy in Chinese patients with chronic hepatitis B.

Background: Peg-Interferon-α treatment is expensive and associated with considerable adverse effects, selection of patients with the highest probability of response is essential for clinical practice. The objective of this study was to assess the relationship between the gene polymorphisms of interleukin-28 (IL-28), p21-activated protein kinase 4 (PAK4) and the response to interferon treatment in chronic hepatitis B patients.

Methods: Two hundred and forty interferon-naive treatment HBeAg seropositive chronic hepatitis B patients were enrolled in the present prospective nested case-control study. Peripheral blood samples were collected, including 92 with favorable response and 148 without response to the interferon treatment. Rs8099917, rs12980602, and rs9676717 SNP was genotyped using matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS).

Results: IL-28 genotype was not associated with response to interferon treatment (OR for GT/GG vs. TT, 0.881 (95%CI 0.388 - 2.002); P = 0.762; OR for CT/CC vs. TT, 0.902 (95%CI 0.458 - 1.778); P = 0.766). Rs9676717 in PAK4 genotype was independently associated with the response (OR for CT/CC vs. TT, 0.524 (95%CI 0.310 - 0.888); P = 0.016). When adjusting for age, gender, smoking, drinking, levels of hepatitis B virus DNA, and alanine aminotransferase (ALT), rs9676717 genotype TT appeared to be associated with a higher probability of response for interferon treatment (OR, 0.155 (95%CI 0.034 - 0.700); P = 0.015).

Conclusion: Genotype TT for rs9676717 in PAK4 gene and no drinking may be predictive of the interferon-a treatment success.