EXPRESSION OF INTERLEUKIN-8 CORRELATES WITH THE METASTATIC POTENTIAL OF HUMAN-MELANOMA CELLS IN NUDE-MICE

We correlated the steady state transcription and protein secretion of interleukin 8 (IL-8) in 13 different human melanoma cell lines with th eir ability to grow and produce metastasis in nude mice. Highly metast atic cells expressed higher steady state levels of IL-8 mRNA transcrip ts than did low metastatic cells. In situ mRNA hybridization analyses confirmed the pattern of mRNA expression on a cellular level. Increase d mRNA expression directly correlated with secretion of IL-8 protein a s determined by enzyme-linked immunosorbent assay. Recombinant IL-8 st imulated the proliferation of low metastatic A375P cells in a dose-dep endent manner, a stimulation that was abrogated by the use of a polycl onal antibody against IL-8. The data suggest that IL-8 can be an autoc rine growth factor for human melanoma cells and that IL-8 is involved in melanoma metastasis.