TLR receptors in laryngeal carcinoma - immunophenotypic, molecular and functional studies

Toll-like receptors (TLRs) have been shown to play crucial role in the recognition of unicellular pathogens. We have shown the expression of three TLRs on tumor cells of human laryngeal carcinoma by means of immunohistochemistry. In the current study we searched presence of TLR1-10 on protein and molecular level in larynx carcinoma cell lines and the impact of respective TLR ligands on TLR expression. Larynx carcinoma cell lines have been used. Cell were subjected to immunocytochemistry. RNA isolated from the cells was tested by RT-PCR. Cells were cultured in the presence of respective TLR ligands. Cells than were harvested and subjected to flow cytometry, using anti TLR1-10 Moabs. The cells were evaluated of membrane and cytoplasmic cell staining. TLR reactivity varied in individual cell lines. RT-PCR allowed to show mRNA for all TLRs tested. After short-term cell culture each cell line exhibited distinct pattern of expression of TLRs following interaction with respective ligand. Cytoplasmic TLR staining had usually higher MFI value than membrane one, but after culture with ligand it became reversed. TLRs 7 and 9 showed highest expression in the majority of tumor cells tested. In conclusion, larynx carcinoma cell lines exhibit rather universal expression of TLRs, both on protein and molecular level. Culture of TLR expressing tumor cells with ligands points out for potential reactivity of tumor cells with TLR agonists, what may have therapeutic implications.