jeudi 14 juin 2007
PRAME is a gene encoding an antigen recognized on a human melanoma by cytolytic T cells.
Human tumor antigens recognized by autologous cytolytic T lymphocytes (CTLs) include 3 classes of proteins : those expressed in tumors but not in normal tissues other than placenta or testis (like MAGE1 ; MIM.300016) ; differentiation antigens expressed in melanocytes or melanomas (like melan-A ; MIM.605513) ; and antigens resulting from point mutations in ubiquitously expressed genes (like MUM1 ; MIM.601900).
The preferentially expressed antigen of melanoma (PRAME) is expressed at high levels in large fractions of human malignancies, as acute myeloid leukemia (AML). Therefore, PRAME is an important marker for diagnosis of various malignant diseases and a relevant parameter for monitoring minimal residual disease.
It is supposed to be involved in tumorigenic processes. Changes in the methylation pattern in defined parts of the regulatory regions of PRAME are sufficient for its upregulation in cells usually not expressing the gene.
Schenk T, Stengel S, Goellner S, Steinbach D, Saluz HP. Hypomethylation of PRAME is responsible for its aberrant overexpression in human malignancies. Genes Chromosomes Cancer. 2007 May 29 ; PMID : 17534929
Ikeda, H. ; Lethe, B. ; Lehmann, F. ; van Baren, N. ; Baurain, J.-F. ; de Smet, C. ; Chambost, H. ; Vitale, M. ; Moretta, A. ; Boon, T. ; Coulie, P. G. :
Characterization of an antigen that is recognized on a melanoma showing partial HLA loss by CTL expressing an NK inhibitory receptor. Immunity 6 : 199-208, 1997. PubMed ID : 9047241
van Baren, N. ; Chambost, H. ; Ferrant, A. ; Michaux, L. ; Ikeda, H. ; Millard, I. ; Olive, D. ; Boon, T. ; Coulie, P. G. : PRAME, a gene encoding an antigen recognized on a human melanoma by cytolytic T cells, is expressed in acute leukaemia cells. Brit. J. Haemat. 102 : 1376-1379, 1998. PubMed ID : 9753074