Characterization of immune cells in non-small cell lung cancer

Lung cancer is the fourth most prevalent cancer in Norway, holding first place in mortality rate. Non-Small Cell Lung Cancer (NSCLC) is the most frequent type, representing about 85% of all lung cancer patients. Presently, the TNM staging, which is based on tumor size and localization, is used for diagnosis and prognosis in NSCLC. However, previous reports suggest that the analysis of tumor-infiltrating immune cells may represent a more accurate prognostic tool. The aim of this project was to perform comprehensive analysis of tumor-infiltrating immune cells in NSCLC using flow cytometry, as a first step to understanding the relationship between tumor-infiltrating immune cells and clinicopathological parameters. We used 10 colour flow cytometry to investigate immune cells in tumors, distant lung tissue, lymph node and peripheral blood, from 67 patients with primary NSCLC. The following populations of tumor-infiltrating immune cells were identified: CD4+ T cells, CD8+ T cells, each with memory and naive phenotypes; CD19+ B cells, with naive, memory, germinal center and plasma cell subsets; CD14+ macrophages, CD123+ plasmacytoid dendritic cells (pDCs), CD11c+CD1c+ dendritic cells (DCs), and CD11c+CD141+ DCs, CD3+CD56+ natural killer T cells (NKT), CD56+ natural killer (NK) cells, with CD16+ and CD16- subset, and four granulocyte population: eosinophils, basophils, neutrophils and mast cells. Statistical analysis revealed increased percentage of leukocytes within tumors compared to distant lung tissue. In the leukocyte population CD19+ B cells showed increase in tumor compared to the distant lung (p= 0.0001). This suggests that tumor microenvironment of NSCLC recruits immune cells and has different immunological structure compared to lung tissue.M-BIOTE