Inhibition of tumor promoter activity toward mouse fibroblasts and their in vitro transformation by tissue inhibitor of metalloproteinases-1 (TIMP-1)

• Published in: Carcinogenesis (New York) Vol. 18; no. 11; pp. 2093 - 2100
• Main Authors: SHOJI, A, SAKAMOTO, Y, TSUCHIYA, T, MORIYAMA, K, KANEKO, T, OKUBO, T, UMEDA, M, MIYAZAKI, K
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 01.11.1997
• Subjects: 3T3 Cells; Animals; Antineoplastic Agents - pharmacology; Biological and medical sciences; Carcinogenesis, carcinogens and anticarcinogens; Cell Communication - drug effects; Cell Transformation, Neoplastic - drug effects; Chemical agents; Fibroblasts - drug effects; Gap Junctions - drug effects; Gap Junctions - physiology; Medical sciences; Metalloendopeptidases - physiology; Methylnitronitrosoguanidine; Mice; Protease Inhibitors - pharmacology; Tetradecanoylphorbol Acetate - pharmacology; Tissue Inhibitor of Metalloproteinase-1 - pharmacology; Tissue Inhibitor of Metalloproteinase-2 - pharmacology; Tumors; Enzyme; Rodentia; Enzyme inhibitor; Metalloendopeptidases; Cell cell interaction; Anticarcinogen; Antitumor promotor; Cell transformation; In vitro; Gap junction; Prevention; Peptidases; Vertebrata; Mammalia; Mouse; Animal; Hydrolases; Tumor promotion; Tumor cell; Interstitial collagenase
• ISSN: 0143-3334; 1460-2180; 1460-2180
• DOI: 10.1093/carcin/18.11.2093

Tissue inhibitor of metalloproteinases-1 (TIMP-1), a natural inhibitor of matrix metalloproteinases (MMPs), is known to inhibit invasion and metastasis of tumor cells. In the present study we examined anti-tumor promoter activity of TIMP-1 and its effect on in vitro cell transformation using BALB/3T3 cells in low serum culture medium. In the dye transfer assay the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) continuously blocked gap-junctional intercellular communication (GJIC) of BALB/3T3 cells in confluent phase. TIMP-1 did not prevent transient inhibition of GJIC induced by TPA, but it quickly restored the reduced GJIC level to the control level. The recovery of GJIC was dependent on the concentration of TIMP-1 from 1 to 1000 ng/ml. In an in vitro two-stage transformation assay in which BALB/3T3 cells were treated with 0.5 microg/ml N-metyl-N'-nitro-N-nitrosoguanidine as initiator and 100 ng/ml TPA as promoter, TIMP-1 at concentrations > 10 ng/ml inhibited the focus formation of transformed cells by approximately 60%. TIMP-2 and a synthetic MMP inhibitor showed a similar inhibitory activity on in vitro cell transformation. Furthermore, zymographyic analysis showed that TPA treatment of BALB/3T3 cells induced secretion of gelatinase B and stromelysin-1 into the culture medium. These results indicate that TIMP-1 and TIMP-2 have inhibitory activity on in vitro transformation of cells. It seems likely that TPA-inducible MMPs are involved in carcinogenesis and TIMPs have a protective role against carcinogenesis in vivo.