Abstract:

Objective To investigate the frequency of different subsets of natural killer（NK） cells in tumor microenvironment and peripheral blood mononuclear cells（PBMCs） from hepatocellular carcinoma（HCC）， and discuss the relationship between NK cells subsets and HCC disease progression. Methods CD3-CD56+， CD3-CD57+ and CD3-CD161+ NK cells were tested from fresh tissue samples and PBMCs by flow cytometry and peripheral blood of 36 healthy volunteers was collected as normal control. Ten HCC specimens were tested by immunohistochemical method to detect the corresponding distribution of CD3-CD56+ NK cells， and normal tissues from 3 benign hepatic tumors were collected as control. Results Flow cytometry detection showed that frequency of CD3-CD56+ cells and CD3-CD57+ cells were（20.6±10.4）％ and（6.9±3.7）％ in 40 HCC tissues， lower than（27.9±13.5）％ and（9.6±5.1）％ in adjacent normal tissues（P＜0.05）. And there was no significant difference in CD3-CD161+ cells（P＞0.05）. The frequency of the 3 kinds of NK cells subsets in HCC PBMCs was higher than that in healthy volunteers， but without differences（P＞0.05）. Immunohistochemical staining showed that there was large amount of CD3-CD56+ NK cells infiltration in adjacent normal tissue of HCC and only a small distribution in tumor tissue， but they were less than CD3-CD56+ NK cells in normal tissues from 3 benign hepatic tumors. The proportion of NK cells in Ⅰ+Ⅱ stage HCC tissues was higher than Ⅲ+Ⅳ stage， especially CD3-CD56+ and CD3-CD161+ NK cells. No linear relationship was found between the frequency of NK cells subsets and gender， number of lesions， AFP， GOT， GUT， leukocytes， hepatic virus infection and TNM stage（P＞0.05）. Conclusion The decrease of NK cells is correlated to the natural immunity and tumor progression of HCC.