Inserm, Institut national de la santé et de la recherche médicale
Faculté de pharmacie, Aix Marseille Université

Accueil » Publications » Communications internationales » Tumor-specific up-regulation of the nonclassical class I HLA-G antigen (...)

Tumor-specific up-regulation of the nonclassical class I HLA-G antigen expression in renal carcinoma

Ibrahim EC, Guerra N, Lacombe MJ, Angevin E, Chouaib S, Carosella ED, Caignard A, Paul P. Cancer Res. 2001 Sep 15 ;61(18):6838-45. Impact factor : 7,856


HLA-G is a nonclassical class I antigen mainly expressed at the maternofetal interface during pregnancy where it is thought to down-modulate maternal immune response against the semiallogeneic fetus. Recent studies indicate that ectopic up-regulation of HLA-G expression on melanoma cells may also favor their escape from antitumor immune response. HLA-G expression was here investigated on paraffin-embedded tumor and adjacent normal renal tissues of 18 renal cell carcinoma (RCC) patients. We provide evidence that HLA-G antigen is differentially expressed in carcinoma and normal renal cells and that up-regulation of this antigen in the tumor cells is more frequent than alterations of other MHC class I or class II antigens. We also demonstrated that HLA-G cell surface expression and secretion is maintained in a tumor cell line (DM) established from an HLA-G-positive RCC lesion. Furthermore, we show that type I (alpha and beta) and, in particular, type II (gamma) IFN treatment enhances steady-state mRNA levels and cell surface expression of HLA-G in the DM cell line. As several studies suggest that HLA-G displays various functional features that allow down-modulation of immune response in vitro, we propose that selective in vivo expression of HLA-G may participate in the impairment of antitumor immunity in RCC.