IL10 and melanoma: To test the hypothesis that IL-27 could promote melanoma progression by inducing IL-10 expression in melanoma cells, we tested the effect of exogenous recombinant IL-27, alone or in combination with TGF-ß1, on IL-10 expression in 4 melanoma cell lines that express the two subunits of the IL-27 receptor, IL-27Rα and gp130 (Figure 4A), but do not express IL-27 (not shown).