GENE-EXPRESSION OF MATRIX METALLOPROTEINASE-1 (INTERSTITIAL COLLAGENASE) AND MATRIX METALLOPROTEINASE-3 (STROMELYSIN-1) IN BASAL-CELL CARCINOMA BY IN-SITU HYBRIDIZATION USING CHONDROITIN ABC LYASE

The gene expression of matrix metalloproteinase-1 and -3 was examined in basal cell carcinomas by in situ hybridization using digoxigenin-la belled riboprobes. Nodulo-ulcerative basal cell carcinomas demonstrate d the gene expression for both metalloproteinases but superficial basa l cell carcinomas did not present any transcripts for them. Transcript s for matrix metalloproteinase-1 (interstitial collagenase) were demon strated densely in stromal cells among tumour masses, and those for ma trix metalloproteinase-3 (stromelysin-1) were detected only in more ad vanced cases. Neither were expressed in tumour cells. The two metallop roteinases were produced by stromal cells according to the tumour inva sion process, in which various growth factors, cytokines and inflammat ory factors, which could regulate gene expressions of matrix metallopr oteinases, were involved. It was also found that hybridization signals were enhanced by treatment with chondroitin ABC lyase, which digested abundant glycosaminoglycans in basal cell carcinoma. The procedure fo r the digestion is simple, and appears to be of value for in situ hybr idization studies on tissues containing large amounts of glycosaminogl ycans.