To assess whether the CCN2 staining of the megakaryocytes by the 10095S antibody was specific, 5 MPN cases showing overexpression as well as 5 normal BM biopsies were additionally stained by 2 other CCN2 antibodies: FG-3114 and the 86641S antibody. This evidence concerns the gene CCN2 and myeloproliferative disorder.