Expression of MIP-3α/CCL20, a macrophage inflammatory protein in oral squamous cell carcinoma

We have examined the expression of MIP-3α/CCL20 in oral squamous cell carcinoma (SCC) in vivo and in vitro. In addition, we have investigated whether the expression of MIP-3α/CCL20 is regulated by bacterial infection and inflammatory cytokines. In order to determine the mRNA level of MIP-3α, quantitative reverse transcription-polymerase chain reaction (RT-PCR) was performed with LightCycler™ using the double-stranded DNA dye, SYBR Green I. Oral epithelial cells and six SCC cell lines (SCC-9, SAS, BSC-OF, HSC-4, HSC, Ca9-22) were found to express MIP-3α mRNA. The expression of MIP-3α was upregulated by infection with Actinobacillus actinomycetemcomitans and by stimulation with lipopolysaccharide and TNF-α. By in situ hybridization, the detectable MIP-3α expression in SCC was localized primarily at the epithelial pearls corresponding to the spinous layer. These results suggest that MIP-3α contributes to the oral immunoresponse to bacterial infection, and may be involved in the growth of SCC.