Head and neck cancer triggers increased IL-6 production of CD34+ stem cells from human cord blood

Background: Head and neck squamous cell carcinoma (HNSCC) are infiltrated by various kinds of immune cells, which show massively impaired immune functions. The influence of HNSCC on CD34 + progenitor cells from human cord blood was analyzed. Materials and Methods: CD34+ cells were isolated from human cord blood by 'magnetic bead separation' using magnetically labelled antibodies. Immunofluorescent staining of CD34 + cells in solid HNSCC was carried out. Cytokine levels of IL-6, IL-8, and IL-10 were analyzed with flow cytometry using the BD CBA Human Soluble Protein Flex Set system (Becton Dickinson). Results: We demonstrated that HNSCC triggered CD34+ cells to produce increased levels of the tumor-promoting cytokine IL-6 and thus they participate in the development of the microenvironment of head and neck cancer. Conclusion: HNSCC modulates the cytokine secretion profile of tumor infiltrating cells to escape from efficient immune responses und to trigger its own malignant progression.