Correlation between the Treg/Thl7 Index and the Efficacy of PD-1 Monoclonal Antibody in Patients with Advanced Non-Small-Cell Lung Cancer Complicated with Chronic Obstructive Pulmonary Disease

Abstract

Objective. It was to explore the correlation between regulatory T cells (Treg)/T helper cell 17 (Thl7) and the efficacy of receiving a programmed death protein-1 (PD-1) monoclonal antibody (mAb) in patients with advanced non-small-cell lung cancer (NSCLC) complicated with chronic obstructive pulmonary disease (COPD). Methods. The research subjects were 82 patients who were clinically evaluated and treated in the Respiratory Department of Suqian Hospital connected with Xuzhou Medical University from January to December 2021. All of the patients were given PD-1 immunotherapy, and 50 healthy people were chosen as the control group. Classification was carried out according to tumor type and tumor stage. The levels of Th17 and Treg/Th17 in the peripheral blood of patients with different tumor-node-metastasis (TNM) stages and different types were compared, and the immune function, lung function (forced expiratory volume in one second/forced vital capacity (FEV1%/FVC), FEV1%, and FVC), and changes in inflammatory factors were compared before and after treatment. The levels of interleukin (IL)-17, IL-6, tumor necrosis factor (TNF)-α, and transforming growth factor (TGF)-β were compared between the two groups. The correlation between Th17 cells and Treg cells in the peripheral blood of patients with NSCLC complicated with COPD was analyzed. Results. After treatment, the levels of IL-17, IL-6, TNF-α, and TGF-β in patients with NSCLC combined with COPD were notably superior to those in the control group ( $P<0.05$ ). The immune function and lung function of the patients were improved after treatment. There were 43 cases of squamous cell carcinoma, 30 cases of adenocarcinoma, and 9 cases of large cell carcinoma. The proportion of Th17 cells to CD4+ T cells in the blood of the three types of patients and the proportion of CD4+CD25HiCD127Lo regulatory T cells to CD4+ lymphocyte cells in Treg cells showed no considerable difference among the different case types ( $P>0.05$ ). No considerable difference was indicated in Treg/Th17 in peripheral blood between stage IIIB and stage IV lung cancer patients ( $P>0.05$ ). A positive linear correlation was revealed between Th17 cells and Treg cells in the peripheral blood of patients with NSCLC combined with COPD, $R=0.26$ , $P=0.039$ . Conclusion. Treg and Th17 cells were shown to be much higher in lung cancer patients with COPD, which could lead to immunosuppression and tumor growth. PD-1 therapy for NSCLC has demonstrated efficacy and can improve patients’ immunological state while being extremely safe.