Enhancement of membrane-type 1-matrix metalloproteinase (MT1-MMP) production and sequential activation of progelatinase A on human squamous carcinoma cells co-cultured with human dermal fibroblasts.
Matrix metalloproteinase 2 (MMP-2)/gelatinase A plays an important role in tumour invasion and metastasis. Since MMP-2 is secreted as an inactive form (proMMP-2) from tumour and neighbouring stroma cells, the activation process is necessary to express the enzymic activity for degradation of extracellular matrix components. We herein reported that the activation of proMMP-2 was induced in human squamous carcinoma cells co-cultured with normal human dermal fibroblasts. When A431 cells were co-cultured with human fibroblasts at various cell ratios, 72-kDa proMMP-2 was converted to a 62-kDa active form through the appearance of a 64-kDa intermediate. The activation of proMMP-2 by co-culture was also observed in other carcinoma cell lines, HSC-4 and SAS, but not in normal human keratinocytes. We characterized by in vitro invasion assay that A431 cells in co-culture preferentially invaded through Matrigel and the increased invasive activity was inhibited by exogenously adding tissue inhibitor of metalloproteinases 2. The augmented proMMP-2 activation by co-culture was achieved by the increase in membrane type 1-MMP (MT1-MMP) production along with that of its mRNA level. The predominant appearance of MT1-MMP was immunologically observed in A431 cells, but not human fibroblasts of the co-culture. Furthermore, epidermal growth factor (EGF) enhanced the co-culture-mediated proMMP-2 activation by increasing the production and gene expression of MT1-MMP, and thereby tumour invasive activity was further augmented. These results suggest that the cell-cell contact between carcinoma cells and normal fibroblasts enhances the production of MT1-MMP followed by sequential activation of proMMP-2 on the tumour cell surface, which may be closely implicated in tumour invasion in vivo.
Sato
T
T
Department of Biochemistry, School of Pharmacy, Tokyo University of Pharmacy and Life Science, Hachioji, Japan.
Iwai
M
M
Sakai
T
T
Sato
H
H
Seiki
M
M
Mori
Y
Y
Ito
A
A
D002294:Carcinoma, Squamous Cell / Q000378:metabolism / Q000503:physiopathology*; D002450:Cell Communication; D004792:Enzyme Precursors / Q000096:biosynthesis / Q000378:metabolism*; D005347:Fibroblasts / Q000502:physiology*; D018093:Gelatinases / Q000096:biosynthesis / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D053504:Matrix Metalloproteinases, Membrane-Associated; D008666:Metalloendopeptidases / Q000096:biosynthesis / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis; D012867:Skin / Q000166:cytology; D014407:Tumor Cells, Cultured
D004792:Enzyme Precursors; D012333:RNA, Messenger; D018093:Gelatinases; D053504:Matrix Metalloproteinases, Membrane-Associated; D008666:Metalloendopeptidases; C069860:progelatinase