Study on the clinical significance and correlation of arginase-1 and inducible nitric oxide synthase expression in hepatocellular carcinoma

Abstract

Objective: To investigate the clinical significance and correlation of arginase 1 (Arg-1) and inducible nitric oxide synthase (iNOS) expression in hepatocellular carcinoma (HCC). Methods: The expression of Arg-1and iNOS in 146 cases of hepatocellular carcinoma tissues and corresponding adjacent tissues was detected by immunohistochemistry. The clinicopathological characteristics and the correlation between the expressions and prognosis were determined by chi square test, Spearman's rank correlation, Kaplan-Meier survival analysis and Cox regression analysis. Results: The positive rates of Arg-1 and iNOS were 18.7% (23/123) and 37.0% (54/146), respectively, which was significantly lower than the adjacent tissues [100%(146/146) and 93.8% (137/146)] and the difference was statistically significant (χ (2) = 212.521, P < 0.01, χ (2) = 104.276, P < 0.01). There was a positive correlation between the both expression (r = 0.331, P < 0.01). Arg-1 low expression was correlated with preoperative serum alpha-fetoprotein (AFP) level, tumor size, differentiation degree, histological types and Edmondson's grade. iNOS low expression was correlated with the differentiation degree and Edmondson's grade (P < 0.05). Kaplan Meier survival analysis showed that in patients with recurrence-free survival (RFs), Arg-1 (+) group > Arg-1 (-) group and Arg-1 (+) iNOS (+) group > Arg-1 (+) iNOS (-) group > Arg-1 (-) iNOS (-) group (P < 0.05). Cox multivariate analysis showed that age, tumor size, Edmondson's grade, vascular tumor emboli were significantly correlated with RFs (P < 0.05). Conclusion: There is a positive correlation between Arg-1 and iNOS expressions in HCC, and both may reflect the HCC malignant degree. The reduced/absent expression of both may participate in the occurrence and development of HCC. The combined detection of Arg-1 and iNOS on HCC may have certain significance for the judgment of differentiation degree and prognosis.