EXPRESSION OF NMA, A NOVEL GENE, INVERSELY CORRELATES WITH THE METASTATIC POTENTIAL OF HUMAN-MELANOMA CELL-LINES AND XENOGRAFTS

nma, a novel gene, was isolated by using a subtractive hybridization t echnique in which the gene expression was compared in a panel of human melanoma cell lines with different metastatic potential. nma mRNA exp ression (1.5 kb) is high in poorly metastatic human melanoma cell line s and xenografts and completely absent in highly metastatic human mela noma cell lines. Fluorescence in site hybridization combined with the analysis of a panel of human-rodent somatic cell hybrids indicated tha t the nma gene is located on human chromosome 10, in the region pl 1.2 -p12.3. Sequence analysis of nma showed no homologies with other known genes or proteins, except for several partially sequenced cDNAs. The predicted amino acid sequence suggests that the protein encoded by nma contains a transmembrane domain. Expression of nma is high in human k idney medulla, placenta and spleen, low in kidney cortex, liver, prost ate and gut and absent in lung and muscle. Whereas nma is not expresse d in normal skin tissue, expression is high in melanocytes and in 3 ou t of 11 melanoma metastases tested. (C) 1996 Wiley-Liss, Inc.