Expression of a Decorin-Like Moleculein Human Melanoma

Andrea LADÁNYI1, Mónika GALLAI2, Sándor PAKU3, Julianna O NAGY4, József DUDÁS4, József TÍMÁR1, Ilona KOVALSZKY4

1Department of Tumor Progression, National Institute of Oncology, Budapest, Hungary
2Department of Molecular Pathology, National Institute of Oncology, Budapest, Hungary
3Department of Molecular Pathology, Joint Organization of the Hungarian Academy of Sciences and Semmelweis University, Budapest, Hungary
41st Institute of Pathology and Experimental Cancer Research, Semmelweis University, Budapest, Hungary


Decorin, a member of the family of small leucin-rich proteoglycans, has originally been described as a secreted proteoglycan component of the connective tissues, and has been implicated in the negative regulation of cell proliferation directly or via interactions with TGF-b. It was reported to be generally absent from tumor cells. Here we show that human melanoma cell lines express a decorin-like molecule. We detected decorin mRNA by RT-PCR in 7 out 7 human melanoma lines characterized by various metastatic potential. Using polyclonal antiserum against the core protein of decorin, the typical 80-120 kD glycanated form as well as a high molecular weight aberrant version (200-210 kD) of decorin were demonstrated by Western blot technique in the culture supernatants as well as in lysates of human melanoma cells. Finally, decorin epitope was also demonstrated immunohistochemically in human melanoma xenografts, as well as in tumor cells of surgically resected melanomas but not in melanocytes of nevi.The expression of this aberrant decorin did not inhibit the in vitroor in vivogrowth of human melanoma cells, and it was independent of their metastatic potential. Human melanoma cell lines expressing aberrant decorin retained sensitivity to the antiproliferative and gelatinase-stimulatory effects of exogenous TGF-b b. Pathology & Oncology Research, Vol 7, Nr 4, 260-266, 2001

Key words: decorin; human melanoma; mRNA; protein; TGF-beta

Received: Sep 24, 2001; accepted: Nov 5, 2001
Correspondence: József TÍMÁR, Department of Tumor Progression, National Institute of Oncology, Ráth György u. 7-9. Budapest H-1122, Hungary; Tel: (36) (1) 224 8786, Fax: (36 1) 224 8706; E-mail:

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