Abstract: Abstract Objective: To investigate the expression of the human leukocyte antigen G (HLA-G) and interleukin-10 (IL-10) in non-small cell lung cancer (NSCLC)，and the correlation between expressions of them. Methods: The expressions of HLA-G and IL-10 were detected using immunohistochemical method in surgically resected specimens from 38 patients with NSCLC (patient group) and normal lung tissues from 12 patients without lung cancer (control group). Results: There were 28 positive expressions of HLA-G (74%) and 30 IL-10 protein expressions (79%) in specimens of NSCLCs, respectively. A positive correlation was found between HLA-G expression and stages of TNM (rs=0.443, P<0.01). No significance correlation was found between IL-10 expression and clinicopathological factors. There was no HLA-G and IL-10 protein expression in normal lung tissues. Furthermore, IL-10 protein expression was demonstrated in 25 (93%) of 28 HLA-G positive cases. There was a positive correlation between them (rs=0.424, P< 0.01). Conclusion: HLA-G and IL-10 form a vicious autocrine circle of immune response abrogation in cancer to help tumor evade immune surveillance.

Key words: non-small-cell lung cancer, HLA-G, IL-10, immunosuppressive