Аннотация:Introduction. It is well known that the bone marrow (BM) is the site of generation and maturation of immunocompetent cells. In addition, BM is an attractive niche for metastatic tumor cells. Тhe immunophenotyping of BM in non-small cell carcinoma of the lung (NSCLC) will provide important information about the features of metastasis, as well as the possibilities of identifying new targets for the treatment of NSCLC.
Purpose of the study is to evaluate the frequency of bone marrow involvement in NSCLC and to study bone marrow populations of immunocompetent cells.
Materials and methods. Immunophenotyping of 62 BM samples from patients with NSCLC was performed using flow cytometry (FACS Canto II, USA, Kaluza Analysis v2.1 software). Monoclonal antibodies to CD45, cytokeratins, CD3, CD4, CD8, CD19, CD20, CD16, CD27, CD25, perforin directly labeled with various fluorochromes were used.
Results. Involvement of BM was found in 43.5% of NSCLC cases. Cases were considered as positive when at least one EPCAM+CD45- cell was detected among 10 million myelokaryocytes (1х10-7). Most often it was observed with more differentiated tumors (p=0.023). The highest detection rates of EPCAM+CD45- cells were observed at stages IA and IIA: 60.7% and 58.3% respectively. Analysis of populations of immunocompetent cells revealed that squamous cell lung cancer was characterized by higher content of BM mature CD3-cells (73% versus 63%, p=0.003), and CD8 lymphocytes (32.4% versus 27.3%, p=0.03). Higher levels of mature B-lymphocytes (CD20+CD45++) were found in adenocarcinoma: 21.7% versus 13.7%, p=0.025. Minor populations of cytotoxic CD4 lymphocytes and CD27 lymphocytes containing perforin were more pronounced in adenocarcinoma: 10.1% versus 2.1% (p=0.008) and 2.9% versus 0.78% (p=0,033). A significant increase in the level of subpopulations of CD16+CD4-NK-cells (p=0.002), CD27+CD3+T-cells (p=0.015) with bone marrow damage was revealed.
Conclusion. Immunophenotyping of BM in NSCLC can be an important tool not only for establishing the spread of cancer process, but also for assess the antitumor immune response. We suppose this may allow the individual approaches in the treatment of this group of patients, as well as development of cancer prevention methods in the future.
Key words: immunophenotyping, bone marrow, non-small cell lung cancer, flow cytometry.