Toll-like receptor 9 mediates invasion and predicts prognosis in squamous cell carcinoma of the mobile tongue.

Background: Toll-like receptor 9 (TLR9) is a cellular receptor, which recognizes bacterial and host-derived DNA. Stimulation of TLR9 induces cellular invasion via matrix metalloproteinase 13 (MMP-13). The aim of this study was to evaluate the role of TLR9 in invasion of oral tongue squamous cell carcinoma (OTSCC).