Abstract:

Objective   To investigate the frequencies of Treg and Th17 in patients with lung adenocarcinoma and explore their clinical significance．  Methods   Frequencies of Treg and Th17 cells were detected in 39 patients with lung adenocarcinoma who were hospitalized from May to November in 2011(lung adenocarcinoma group) and 20 healthy volunteers(control group) by flow cytometry． Enzyme-linked immunosorbent assay (ELISA) was used to detect serum concentration of IL-17. The above indexes were compared among patients in gradeⅠ+Ⅱ, grade Ⅲ+Ⅳ and 14 patients who underwent operations. Follow-up visits were performed for the postoperative patients. The follow-up indexes include local recurrence, lymph node metastasis, distant metastasis and functional assessment of cancer therapy -lung(FACT-L). The relationships between these indexes and the levels of Treg and Th17 were then analyzed. Results   ① Levels of Treg, Th17 cells and IL-17 in lung adenocarcinoma group were significantly higher than those in control group. ② Frequency of Treg had positive correlation with the situation of lymph node metastasis and distant metastasis, while levels of Th17 and IL17 had negative correlation with it. ③ Frequency of Th17 in the postoperative patients was significantly lower than that in the preoperative patients, accompanied by1decreased serum concentration of IL-17. ④ FACT-L in postoperative patients had negative correlation with the level of Treg before operation, while it had positive correlation with the level of Th17 before operation. Postoperative patients had higher relapse and metastasis rate when preoperative Treg＞mean of Treg and Th17＜mean of Th17. Conclusion   There are abnormal changes of Treg and Th17 which are related to the tumor load in the peripheral blood of patients with lung adenocarcinoma. High proportion of Treg is the negative prognostic factor of lung adenocarcinoma, which may be closely related to the inhibition of CD8+T cells. High proportion of Th17 probably has a positive impact on the favorable prognosis of lung adenocarcinoma.

Key words: Treg cells; Th17 cells; Lung adenocarcinoma; Tumor immunity； Flow cytometry； ELISA