Background: Cytokines play an essential role in the pathogenesis of hepatitis C virus (HCV) related cirrhosis and hepatocellular carcinoma (HCC). Interleukin-9 (IL-9) participates in inflammation, autoimmunity and tumor immunity. IL-9 was reported to affect liver fibrosis, severity and prognosis of HCV related diseases.
Aim of the study: To assess the potential correlation of serum IL-9 level and its receptor with the progression and prognosis of patients having HCV related chronic liver disease and its probable association with hepatocellular carcinoma.
Methods: Sixty-eight patients having HCV chronic liver disease and 20 apparently healthy controls (HCs) were enrolled in the study. The patients were grouped into 3 groups: 18 patients having compensated chronic liver disease (CCLD), 18 patients having decompensated chronic liver disease, and 32 patients having hepatocellular carcinoma (HCC). Serum IL-9 level was estimated by ELISA and IL-9 receptor (IL-9R) gene expression was assessed by RT-PCR in HCC group and HCs.
Results: IL-9 level was significantly higher in patients in comparison to HCs and there was statistically significant difference between the 3 patients' groups (p < 0.001). IL-9 was correlated with different laboratory and clinical parameters. At a cut-off value of >1600pg/ml, IL-9 had the ability to differentiate between CCLD group and HCC group with 75% sensitivity and 94.44% specificity. There was a highly significant statistical difference between HCC group and HCs in IL-9R gene expression (p < 0.001).
Conclusion: Serum IL-9 level is higher in chronic HCV infected patients than in HCs. IL-9R gene expression is higher among HCC patients than in HCs.