Since we demonstrated that IL-1β-induced collagen invasion of RCC cells was dependent on MMP enzymatic activity (Fig. 1E) and that IL-1β-induced MMP expression was dependent on CEBPβ (Fig. 5), we next asked whether or not CEBPβ was required for IL-1β-mediated RCC tumor cell invasion. This evidence concerns the gene CEBPB and neoplasm.