ABSTRACT
The expression of granulysin, a cytolytic protein produced by activated T and NK cells, has been revealed to be correlated with the prognosis of some adult cancer patients. By examination on various childhood lymphoma tissues, we found that granulysin level was especially high in systemic anaplastic large cell lymphoma (ALCL) cases, whereas no close correlation with the expression of CD96, a marker for activated T and NK cells, was observed. We further demonstrated that both ALCL cells in biopsy specimens and cell lines established from ALCL express granulysin, indicating some correlation of granulysin with biological features of ALCL.
Subject(s)
Antigens, Differentiation, T-Lymphocyte/genetics , Burkitt Lymphoma/genetics , Hodgkin Disease/genetics , Lymphoma, B-Cell/genetics , Lymphoma, Large B-Cell, Diffuse/genetics , Lymphoma, Large-Cell, Anaplastic/genetics , RNA, Messenger/genetics , Adolescent , Adult , Aged , Antigens, CD/genetics , Antigens, CD/metabolism , Antigens, Differentiation, T-Lymphocyte/metabolism , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Burkitt Lymphoma/metabolism , Burkitt Lymphoma/pathology , Female , Flow Cytometry , Hodgkin Disease/metabolism , Hodgkin Disease/pathology , Humans , Killer Cells, Natural/metabolism , Killer Cells, Natural/pathology , Lymphoma, B-Cell/metabolism , Lymphoma, B-Cell/pathology , Lymphoma, Large B-Cell, Diffuse/metabolism , Lymphoma, Large B-Cell, Diffuse/pathology , Lymphoma, Large-Cell, Anaplastic/metabolism , Lymphoma, Large-Cell, Anaplastic/pathology , Male , Middle Aged , Prognosis , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Tumor Cells, Cultured , Young AdultABSTRACT
BACKGROUND: The Dickkopf (DKK) family comprises a set of proteins that function as regulators of Wnt/beta-catenin signaling and has a crucial role in development. Recent studies have revealed the involvement of this family in tumorigenesis, however their role in tumorigenesis is still remained unclear. METHODOLOGY/PRINCIPAL FINDINGS: We found increased expression of DKK2 but decreased expression of DKK1 in Ewing family tumor (EFT) cells. We showed that EFT-specific EWS/ETS fusion proteins enhance the DKK2 promoter activity, but not DKK1 promoter activity, via ets binding sites (EBSs) in the 5' upstream region. EWS/ETS-mediated transactivation of the promoter was suppressed by the deletion and mutation of EBSs located upstream of the DKK2 gene. Interestingly, the inducible expression of EWS/ETS resulted in the strong induction of DKK2 expression and inhibition of DKK1 expression in human primary mesenchymal progenitor cells that are thought to be a candidate of cell origin of EFT. In addition, using an EFT cell line SK-ES1 cells, we also demonstrated that the expression of DKK1 and DKK2 is mutually exclusive, and the ectopic expression of DKK1, but not DKK2, resulted in the suppression of tumor growth in immuno-deficient mice. CONCLUSIONS/SIGNIFICANCE: Our results suggested that DKK2 could not functionally substitute for DKK1 tumor-suppressive effect in EFT. Given the mutually exclusive expression of DKK1 and DKK2, EWS/ETS regulates the transcription of the DKK family, and the EWS/ETS-mediated DKK2 up-regulation could affect the tumorigenicity of EFT in an indirect manner.
Subject(s)
Intercellular Signaling Peptides and Proteins/genetics , Proto-Oncogene Protein c-ets-1/physiology , RNA-Binding Protein EWS/physiology , Base Sequence , Blotting, Western , Cell Line, Tumor , Chromatin Immunoprecipitation , DNA Primers , Humans , Promoter Regions, Genetic , Reverse Transcriptase Polymerase Chain ReactionABSTRACT
OBJECTIVE: Insulin-like growth factor (IGF)-binding proteins (IGFBPs) are a family of proteins thought to modulate IGF function. By employing an in vitro culture system of human hematopoietic stem cells cocultured with murine bone marrow stromal cells, we examined the effects of IGF-I and IGFBPs on early B-cell development. MATERIALS AND METHODS: Human CD34(+) bone marrow cells were cocultured with murine stromal MS-5 cells for 4 weeks, and pro-B-cell number was analyzed by flow cytometry. After administration of reagents that are supposed to modulate IGF-I or IGFBP function to the culture, the effect on pro-B-cell development was examined. RESULTS: After cultivation for 4 weeks, effective induction of pro-B-cell proliferation was observed. Experiments using several distinct factors, all of which neutralize IGF-I function, revealed that impairment of IGF-I function results in a significant reduction in pro-B-cell development from CD34(+) cells. In addition, when the effect of recombinant proteins of IGFBPs and antibodies against IGFBPs were tested, IGFBP-3 was found to inhibit pro-B-cell development, while IGFBP-6 was required for pro-B-cell development. CONCLUSIONS: IGF-I is essential for development of bone marrow CD34(+) cells into pro-B cells. Moreover, IGFBPs are likely involved in regulation of pro-B-cell development.
Subject(s)
B-Lymphocytes/physiology , Cell Differentiation/drug effects , Hematopoietic Stem Cells/physiology , Insulin-Like Growth Factor Binding Proteins/pharmacology , Insulin-Like Growth Factor I/pharmacology , Animals , Antigens, CD34/metabolism , B-Lymphocytes/cytology , Cell Differentiation/physiology , Cell Line, Tumor , Cell Proliferation/drug effects , Coculture Techniques , Flow Cytometry , Hematopoietic Stem Cells/cytology , Humans , Insulin-Like Growth Factor Binding Proteins/metabolism , Insulin-Like Growth Factor I/metabolism , Mice , Stromal Cells/cytology , Stromal Cells/physiologyABSTRACT
A mouse monoclonal antibody (MAb) was generated against swine leukocyte antigen (SLA) class I alpha chain. A newly developed series of MAb clones that react with pan leukocytes were selected and tested by immuno-histochemistry using SLA class I alpha chain expressing Cos-7 cells. Among them, MAb 4G8 was characterized by the following features: (1) 4G8 reacted with Cos-7 cells transfected with SLA class I alpha chain from the d haplotype, (2) 4G8 recognized epitopes that were different from those of commercially available anti-SLA class I MAbs 74-11-10 and PT85A, and (3) 4G8 could be used to immunostain frozen sections of thymus, spleen, lymph node, kidney, and liver tissues with good results.
