title: Cell-type specific regulation of human interstitial collagenase-1 gene expression by interleukin-1 beta (IL-1 beta) in human fibroblasts and BC-8701 breast cancer cells.
abstract: Interleukin-1 beta (IL-1 beta) is a potent cytokine that stimulates interstitial collagenase-1 (matrix metalloproteinase-1; MMP-1). In this study, we compared the mechanism(s) by which IL-1 beta induces collagenase gene expression in two very different cells, normal human foreskin fibroblasts (HFFs) and an aggressive breast cancer cell line, BC-8701 cells. Northern analysis showed that the time course of collagenase induction was distinct in the two cells: although both cells expressed low levels of MMP-1 constitutively, addition of IL-1 beta increased MMP-1 mRNA in HFFs by 1 h and levels remained high over a 24-h period. In contrast, MMP-1 levels in IL-1 beta-treated BC-8701 cells did not increase until 4 h, peaked by 12 h and then declined. To analyze the transcriptional response, we cloned and sequenced more than 4,300 bp of the human MMP-1 promoter, and from this promoter clone, we prepared a series of 5'-deletion constructs linked to the luciferase reporter and transiently transfected these constructs into both cell types to measure both basal and IL-1 beta induced transcription. When both cell types were uninduced, promoter fragments containing less than 2,900 bp gave only a minimal transcriptional response, while larger fragments showed increased transcriptional activity. With IL-1 beta treatment, significant responsiveness (P < 0.001) in HFFs was seen only with the larger fragments, while in the BC-8701 cells, all fragments were significantly induced with IL-1 beta. Finally, we found that IL-1 beta stabilized MMP-1 mRNA in normal fibroblasts, but not in BC-8701 breast cancer cells. We conclude that both the transcriptional and post-transcriptional regulation of MMP-1 gene expression by IL-1 beta is controlled by cell-type specific mechanisms, and we suggest that IL-1 induced MMP-1 expression in tumor cells and in neighboring stromal cells may amplify the invasive ability of tumor cells.
authors.affiliation: Department of Pharmacology and Toxicology, Dartmouth Medical School, Hanover, New Hampshire 03755, USA.
authors.forename: J L
authors.initials: JL
authors.lastname: Rutter
authors.forename: U
authors.initials: U
authors.lastname: Benbow
authors.forename: C I
authors.initials: CI
authors.lastname: Coon
authors.forename: C E
authors.initials: CE
authors.lastname: Brinckerhoff
mesh_terms: D001483:Base Sequence; D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D017364:Collagenases / Q000187:drug effects / Q000235:genetics*; D004004:Dichlororibofuranosylbenzimidazole / Q000494:pharmacology; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic; D016758:Genes, jun; D006207:Half-Life; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology*; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D020781:Matrix Metalloproteinase 1; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger; D011994:Recombinant Proteins / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D012867:Skin / Q000166:cytology; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured
chemical_list: D007375:Interleukin-1; D012333:RNA, Messenger; D011994:Recombinant Proteins; D004004:Dichlororibofuranosylbenzimidazole; D008156:Luciferases; D017364:Collagenases; D020781:Matrix Metalloproteinase 1