title: Functional analysis of matrix metalloproteinases and tissue inhibitors of metalloproteinases differentially expressed by variants of human HT-1080 fibrosarcoma exhibiting high and low levels of intravasation and metastasis.
abstract: The role of tumor-derived matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinase (TIMPs) in cancer cell dissemination was analyzed by employing two variants of human HT-1080 fibrosarcoma, HT-hi/diss and HT-lo/diss, which differ by 50-100-fold in their ability to intravasate and metastasize in the chick embryo. HT-hi/diss and HT-lo/diss were compared by quantitative reverse transcription-PCR and Western blot analyses for mRNA and protein expression of nine MMPs (MMP-1, -2, -3, -7, -8, -9, -10, -13, and -14) and three TIMPs (TIMP-1, -2, and -3) in cultured cells in vitro and in primary tumors in vivo. MMP-1 and MMP-9 were more abundant in the HT-hi/diss variant, both in cultures and in tumors, whereas the HT-lo/diss variant consistently expressed higher levels of MMP-2, TIMP-1, and TIMP-2. Small interfering RNA-mediated down-regulation of MMP-2 and TIMP-2 increased intravasation of HT-lo/diss cells. Coordinately, treatment of the developing HT-hi/diss tumors with recombinant TIMP-1 and TIMP-2 significantly reduced HT-hi/diss cell intravasation. However, a substantial increase of HT-hi/diss dissemination was observed upon small interfering RNA-mediated down-regulation of three secreted MMPs, including the interstitial collagenase MMP-1 and the two gelatinases, MMP-2 and MMP-9, but not the membrane-tethered MMP-14. The addition of recombinant pro-MMP-9 protein to the HT-hi/diss tumors reversed the increased intravasation of HT-hi/diss cells, in which MMP-9 was stably down-regulated by short hairpin RNA interference. This rescue did not occur if the pro-MMP-9 was stoichiometrically complexed with TIMP-1, pointing to a direct role of the MMP-9 enzyme in regulation of HT-hi/diss intravasation. Collectively, these findings demonstrate that tumor-derived MMPs may have protective functions in cancer cell intravasation, i.e. not promoting but rather catalytically interfering with the early stages of cancer dissemination.
authors: Department of Cell Biology, The Scripps Research Institute, La Jolla, California 92037, USA.
authors: Juneth J
authors: JJ
authors: Partridge
authors: Mark A
authors: MA
authors: Madsen
authors: Veronica C
authors: VC
authors: Ardi
authors: Thales
authors: T
authors: Papagiannakopoulos
authors: Tatyana A
authors: TA
authors: Kupriyanova
authors: James P
authors: JP
authors: Quigley
authors: Elena I
authors: EI
authors: Deryugina
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D002642:Chick Embryo; D005354:Fibrosarcoma / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D061965:Matrix Metalloproteinase Inhibitors; D020782:Matrix Metalloproteinases / Q000096:biosynthesis*; D009361:Neoplasm Invasiveness; D009362:Neoplasm Metastasis; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D009368:Neoplasm Transplantation; D034741:RNA, Small Interfering / Q000494:pharmacology; D011994:Recombinant Proteins / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000494:pharmacology; D019714:Tissue Inhibitor of Metalloproteinases / Q000037:antagonists & inhibitors / Q000096:biosynthesis* / Q000494:pharmacology
chemical_list: D061965:Matrix Metalloproteinase Inhibitors; D009363:Neoplasm Proteins; D034741:RNA, Small Interfering; D011994:Recombinant Proteins; D019714:Tissue Inhibitor of Metalloproteinases; D020782:Matrix Metalloproteinases