OSCC cells Cal27, PCI13 and UMSCC19, keratinocytes hTERT HAK Clone 41, and monocytoid THP1 cells were incubated × 15 min with EGF, TLR2/1 ligand Pam3CSK4, TLR2/6 ligand FSL-1, A2a-selective agonist CGS21689, non-selective AR agonist NECA, as detailed in Materials and Methods. The A2a-selective antagonist ZM 241385 was added in some experiments four hours prior to other stimuli. Protein was analyzed as described in Materials and Methods. Briefly, samples were separated by SDS-PAGE electrophoresis, transferred to nitrocellulose membrane, and probed for pERK1/2, total ERK1/2, and GAPDH. Charts are representative of the blots shown. Data represent up to 4 independent experiments for each cell line.