MRNA expression of matrix metalloproteases and their inhibitors differs insubtypes of renal cell carcinomas

Altered expression of matrix metalloproteases (MMPs) and their inhibitors, the tissue inhibitors of matrix metalloproteases (TIMPs), has been demonstr ated in various tumour tissues. mRNA expression patterns of MMP-1, MMP-2, M MP-3, MMP-9, MMP-11, MMP-12, MMP-14 and TIMP-1, TIMP-2, TIMP-3 and TIMP-4 w ere evaluated by quantitative reverse transcriptase-polymerase chain reacti on (RT-PCR) in 30 renal cell carcinomas (RCC), as well as in the surroundin g tissues. Expression of the MMPs was significantly stronger in the carcino mas than in non-malignant tissues. High levels were demonstrated particular ly in clear cell RCCs (CC-RCC). Except for MMP-1, MMP expression in the pap illary RCCs (P-RCC) was, for most MMPs, significantly lower. Expression of the TIMPs in malignant cells of both subtypes was weak, with the exception of TIMP-4 which was strongly expressed in the P-RCCs and downregulated in t he CC-RCCs. The latter was correlated with chromosomal loss of 3p, harbouri ng the TIMP-4 gene locus. In conclusion, deregulated expression of the MMPs and TIMPs in RCCs differs according to histology, grade, size and cytogene tic characteristics, suggesting that MMP and TIMP expression patterns play an important role for the typical histomorphological features of RCC subtyp es and their respective biological behaviour. (C) 2001 Published by Elsevie r Science Ltd.