Enhanced circulating ILC2s and MDSCs may contribute to ensure maintenance of Th2 predominant in patients with lung cancer

Group 2 innate lymphoid cells (ILC2s) were demonstrated to be involved in the initiation and coordination of type 2 T helper cell (Th2) responses. Myeloid-derived suppressor cells (MDSCs) have received a great deal of attention for their role in creating an immunosuppressive microenvironment in cancer-bearing hosts. However, the contributions of ILC2s in the occurrence and development of lung cancer, and the association between ILC2s and Th2 or MDSCs in lung cancer remain to be elucidated. In the present study, 36 patients newly diagnosed with lung cancer based on the guidelines of the International Union Against Cancer Tumor Node Metastasis were included. The frequencies of ILC2s and MDSCs in peripheral blood mononuclear cells were determined, and the mRNA expression levels of ILC2s or Th2-related transcription factors and cytokines, and MDSCs-related products were assessed. The results demonstrated that the frequencies of the circulatory ILC2s and MDSCs were enhanced in lung cancer patients, as were ILC2-related transcription factors and cytokines in peripheral blood. A positive correlation was identified between the Th2-dominated phenotype and the expression levels of ILC2s-associated cytokines or transcription factors. In addition, increased autophagy related 1 was closely associated with Th2-associated transcription factors. It was demonstrated that ILC2s and MDSCs were clearly upregulated and accompanied by a predominant Th2 phenotype in patients with lung cancer; this may lead to new immunotherapy approaches for lung cancer based on the associated metabolites and cytokines.