Overexpression of immunosuppressive cytokines is associated with poorer clinical stage of oral squamous cell carcinoma

• We report a high tissue expression of IL-10 and TGF-β2 in OSCC.
• High expression of IL-10 and TGF-β2 was observed in metastatic neoplastic cells.
• There was a high IL-10 expression in advanced clinical stage tumours.
• The immunosuppressive environment in OSCC that can contribute to poor prognosis.

ObjectiveThe aim of this study was to evaluate the expression of IL-10 and TGF-β2 in oral squamous cell carcinoma (OSCC) and its relationship with prognostic clinical and microscopic parameters.DesignImmunohistochemistry was used to assess the expression of IL-10 and TGF-β2 in OSCC samples from 43 patients who had undergone surgical excision and neck dissection. Metastatic lymph nodes were included in the study (n = 23). Samples of healthy oral mucosa (n = 20) were used as controls. The sections were evaluated using a semi-quantitative method in conjunction with staining intensity.ResultsOur findings showed that the expression of IL-10 and TGF-β2 by neoplastic and stromal cells was high in most of the OSCC samples (>70% of samples), especially when compared to the controls (≅10% of samples) (P < 0.05). OSCC neoplastic cells in cervical lymph nodes were also positive for IL-10 and TGF-β2. An association between high expression of IL-10 by neoplastic cells and advanced clinical stage (T3-T4) was verified (P = 0.02). Although not statistically significant, the expression of TGF-β2 was also augmented in advanced stage tumours.ConclusionsThese data suggest that the ability of OSCC neoplastic cells to secrete immunosuppressive cytokines could contribute to clinical progression by maintaining a microenvironment conducive to evasion and tumour proliferation.