The transcription factor PU.1, necessary for B-cell development is expressed in lymphocyte predominance, but not classical Hodgkin's disease.
Hodgkin's disease (HD) is a lymphoproliferative disease of predominantly B-cell origin. However, the reasons for the incomplete development of the B-cell phenotype and lack of immunoglobulin expression in classical HD (cHD) have not been fully explained. We examined the expression of PU.1 in HD, an Ets-family transcription factor, which regulates the expression of immunoglobulin and other genes that are important for B-cell development. Immunohistochemistry for PU.1 was performed on 35 cases of cHD and 15 cases of lymphocyte predominance HD as well as 67 non-Hodgkin's lymphomas (NHL). Expression of PU.1 was studied by Western blotting in four cHD-derived cell lines and in five NHL cell lines. We also studied the expression of two additional B-cell transcription factors, B-cell-specific activator protein and Oct-2. Our results show a striking lack of PU.1 expression by neoplastic cells in cHD but not in lymphocyte predominance HD. Our study also confirmed that B-cell-specific activator protein but not Oct-2 is not expressed by cHD. Western blotting showed no PU.1 protein expression in the cHD-derived cell lines, with the exception of one cell line of putative monocyte/histiocyte origin. The lack of PU.1 protein expression in cHD likely contributes to the lack of immunoglobulin expression and incomplete B-cell phenotype characteristic of the Reed-Sternberg cells in cHD.
Torlakovic
E
E
Department of Pathology, The Norwegian Radium Hospital, Oslo, Norway. emina.torlakovic@labmed.uio.no
Tierens
A
A
Dang
H D
HD
Delabie
J
J
D015153:Blotting, Western; D004268:DNA-Binding Proteins / Q000378:metabolism; D006689:Hodgkin Disease / Q000145:classification / Q000378:metabolism* / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008198:Lymph Nodes / Q000378:metabolism / Q000473:pathology; D008214:Lymphocytes / Q000378:metabolism* / Q000473:pathology*; D008228:Lymphoma, Non-Hodgkin / Q000378:metabolism; D050813:Octamer Transcription Factor-2; D010641:Phenotype; D011518:Proto-Oncogene Proteins / Q000502:physiology*; D015534:Trans-Activators / Q000502:physiology*; D014157:Transcription Factors / Q000378:metabolism; D014407:Tumor Cells, Cultured; D000099232:Proto-Oncogene Protein Spi-1
D004268:DNA-Binding Proteins; D050813:Octamer Transcription Factor-2; D011518:Proto-Oncogene Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D000099232:Proto-Oncogene Protein Spi-1; C058435:POU2F2 protein, human