Abstract: Objective To study the distribution of CD4 + CD25 + regulatory T cells (Treg) in normal liver tissue,the liver focal nodular hyperplasia(FNH),atypical adenomatous hyperplasia of the liver(AAH) , hepatocellular carcinoma (HCC) and side of cancer. We will evaluate its the role in tumor occurrence and development. Methods The expression of treg cells were measured in 90 cases with double ELISA method of immunohistochemical staining. Analysis of its expression and significance in hepatocellular carcinoma.Rusult Normal liver tissue, FNH group were not found in the expression of Treg cells. AAH and HCC group have the expression of Treg cells. Treg cells of HCC group was signifieantly higher than in AAH group(P=0.000), The expression of Treg Cells was no significant difference between different age and sex and preoperative AFP value (P> 0.05); It is a relationship between treg cells number and the size of tumor, Treg cells of Enveloped group was signifieantly higher than in no capsule group,Comparison between normal and upper groups of Preoperative HBV-DNA was statistically significant difference.(P=0.007).Conclusion The increase of Treg cells favor occurrence and development of the tumor. It is plays a negative regulatory role in the immune of the tumor. Remove or reduce the Treg cells of the liver micro-environment may increase the effect of tumor immunotherapy.

Key words: CD4+CD25+regulatory T cells, The liver focal nodular hyperplasia, Atypical adenomatous hyperplasia of the liver, Hepatocellular carcinoma