Influence of conditioned medium from squamous cell carcinoma of the tongue on lymphoblasts and peripheral blood mononuclear cells.

ABSTRACT

BACKGROUND: Squamous cell carcinoma (SCC) is the most common malignant neoplasm of the oral cavity and is associated with high morbidity and mortality. Attention has been given to the role of inflammatory cells in carcinogenesis because of the ability of cancer cells to subvert the immune response. However, little is known about how molecules from neoplastic cells interact with lymphoblasts and circulating immune cells. This study aimed to understand the mechanisms by which SCC cells modulate the immune response by analyzing the influence of conditioned medium derived from SCC cell lines on immune cells. METHODS: Lymphoblastic cells (CEM) and peripheral blood mononuclear cells (PBMC) were cultured in a conditioned medium derived from squamous cell carcinoma cells (SCC9 or SCC4) and analyzed for cell viability, CD4/CD8/FOXP3 profile by flow cytometry, and chemokine levels. RESULTS: Conditioned medium derived from SCC4 and SCC9 presented higher concentrations of IL-6 and IL-8 than IL-1ß, IL-10, and IFN-γ. CEM and PBMCs when cultured with conditioned medium derived from SCC4 and SCC9 reduced IL-1ß, IL-8, and IFN-γ concentrations. Conditioned medium from SCC4 increased CD4+ population in both CEM and PBMCs, while in conditioned medium from SCC9 it occurred only in PBMCs. PBMCs when cultured with both conditioned mediums increased CD8+ /FOXP3+ cells. CEM cells when cultured with conditioned medium derived from SCC4 and SCC9 reduced. CONCLUSION: Collectively, our results suggest that the products derived from squamous cell carcinoma on inflammatory cells can promote an immunosuppressed environment by reducing cell viability, changing cytokine expression, and altering the cell immunoprofile.