transforming-growth-factor-beta and Sarcoma--Ewing

transforming-growth-factor-beta has been researched along with Sarcoma--Ewing* in 13 studies

Other Studies

13 other study(ies) available for transforming-growth-factor-beta and Sarcoma--Ewing

ArticleYear
The expression changes of PD-L1 and immune response mediators are related to the severity of primary bone tumors.
    Scientific reports, 2023, Nov-22, Volume: 13, Issue:1

    The expression pattern, diagnostic value, and association of PD-L1, IFN-γ and TGF-β with bone tumor type, severity, and relapse are determined in this study. 300 human samples from patients with osteosarcoma, Ewing sarcoma, and GCT were enrolled. The PD-L1 gene and protein expression were assessed by qRT-PCR and immunohistochemistry, respectively. ELISA and flow cytometry was used to detect cytokines and CD4/CD8 T cell percentages, respectively. A considerable increase in PD-L1 level was detected in bone tumor tissues at both gene and protein levels that was considerable in osteosarcoma and Ewing sarcoma. A positive correlation was detected regarding the PD-L1 and tumor metastasis and recurrence in osteosarcoma and Ewing sarcoma. The increased IFN-γ level was detected in patients with metastatic, and recurrent osteosarcoma tumors that were in accordance with the level of TGF-β in these samples. The simultaneous elevation of IFN-γ and TGF-β was detected in Ewing sarcoma and GCT, also the CD4 + /CD8 + ratio was decreased significantly in patients with osteosarcoma compared to GCT tumors. The elevated levels of PD-L1, TGF- β, and IFN-γ were associated with bone tumor severity that can provide insights into the possible role of this axis in promoting immune system escape, suppression, and tumor invasion.

    Topics: B7-H1 Antigen; Bone Neoplasms; CD8-Positive T-Lymphocytes; Humans; Immunity; Immunologic Factors; Osteosarcoma; Sarcoma, Ewing; Transforming Growth Factor beta

2023
CRISPR activation screen identifies TGFβ-associated PEG10 as a crucial tumor suppressor in Ewing sarcoma.
    Scientific reports, 2022, 06-23, Volume: 12, Issue:1

    As the second most common pediatric bone and soft tissue tumor, Ewing sarcoma (ES) is an aggressive disease with a pathognomonic chromosomal translocation t(11;22) resulting in expression of EWS-FLI1, an "undruggable" fusion protein acting as transcriptional modulator. EWS-FLI1 rewires the protein expression in cancer cells by activating and repressing a multitude of genes. The role and contribution of most repressed genes remains unknown to date. To address this, we established a CRISPR activation system in clonal SKNMC cell lines and interrogated a custom focused library covering 871 genes repressed by EWS-FLI1. Among the hits several members of the TGFβ pathway were identified, where PEG10 emerged as prime candidate due to its strong antiproliferative effect. Mechanistic investigations revealed that PEG10 overexpression caused cellular dropout via induction of cell death. Furthermore, non-canonical TGFβ pathways such as RAF/MEK/ERK, MKK/JNK, MKK/P38, known to lead to apoptosis or autophagy, were highly activated upon PEG10 overexpression. Our study sheds new light onto the contribution of TGFβ signalling pathway repression to ES tumorigenesis and suggest that its re-activation might constitute a novel therapeutic strategy.

    Topics: Apoptosis Regulatory Proteins; Cell Line, Tumor; Child; Clustered Regularly Interspaced Short Palindromic Repeats; DNA-Binding Proteins; Gene Expression Regulation, Neoplastic; Humans; Neuroectodermal Tumors, Primitive, Peripheral; Oncogene Proteins, Fusion; Proto-Oncogene Protein c-fli-1; RNA-Binding Protein EWS; RNA-Binding Proteins; Sarcoma, Ewing; Transforming Growth Factor beta

2022
TrkC, a novel prognostic marker, induces and maintains cell survival and metastatic dissemination of Ewing sarcoma by inhibiting EWSR1-FLI1 degradation.
    Cell death & disease, 2022, 09-28, Volume: 13, Issue:9

    Upregulation of EWSR1-FLI1 expression has been associated with invasiveness, induced cell survival, metastatic dissemination, and acquisition of self-renewal traits in Ewing sarcoma (ES). Although existing evidence implies that TrkC expression is linked to the pathogenesis of other cancer types, its role and the mechanism behind its correlation with EWSR1-FLI1 in the pathogenesis of ES remain unclear. In this study, we uncovered a novel physiological role of TrkC as a key regulator of EWSR1-FLI1 involved in the survival and metastatic dissemination of ES. TrkC was observed to be frequently overexpressed in human metastatic ES cells in vitro and in vivo, facilitating enhanced survival, tumorigenicity, and metastasis of ES cells. TrkC-mediated metastasis of ES cells was induced by the inhibition of the proteasomal degradation of EWSR1-FLI1 via the TrkC/EWSR1-FLI1 complex, which subsequently enabled the induction of the target proteins, EGR2 and NKX2.2. Moreover, TrkC significantly inhibited tumor suppressor activity of TGF-β through reduction of the mRNA expression of one of its receptors, TGFBR2 via TrkC-induced stabilization of EWSR1-FLI1. Furthermore, loss of TrkC expression inhibited tumor growth and metastasis in experimental mouse models. This study is the first to report the involvement and functional role of TrkC in the pathogenesis of ES, suggesting important implications for understanding the alterations of TrkC in Ewing tumors.

    Topics: Animals; Cell Line, Tumor; Cell Survival; Humans; Mice; Oncogene Proteins, Fusion; Prognosis; Proto-Oncogene Protein c-fli-1; Receptor Protein-Tyrosine Kinases; Receptor, Transforming Growth Factor-beta Type II; Receptor, trkC; RNA-Binding Protein EWS; RNA, Messenger; Sarcoma, Ewing; Transforming Growth Factor beta

2022
The role of miR-17-92 in the miRegulatory landscape of Ewing sarcoma.
    Oncotarget, 2017, Feb-14, Volume: 8, Issue:7

    MicroRNAs serve to fine-tune gene expression and play an important regulatory role in tissue specific gene networks. The identification and validation of miRNA target genes in a tissue still poses a significant problem since the presence of a seed sequence in the 3'UTR of an mRNA and its expression modulation upon ectopic expression of the miRNA do not reliably predict regulation under physiological conditions. The chimeric oncoprotein EWS-FLI1 is the driving pathogenic force in Ewing sarcoma. MiR-17-92, one of the most potent oncogenic miRNAs, was recently reported to be among the top EWS-FLI1 activated miRNAs. Using a combination of AGO2 pull-down experiments by PAR-CLIP (Photoactivatable-Ribonucleoside-Enhanced Crosslinking and Immunoprecipitation) and of RNAseq upon miRNA depletion by ectopic sponge expression, we aimed to identify the targetome of miR-17-92 in Ewing sarcoma. Intersecting both datasets we found an enrichment of PAR-CLIP hits for members of the miR-17-92 cluster in the 3'UTRs of genes up-regulated in response to mir-17-92 specific sponge expression. Strikingly, approximately a quarter of these genes annotate to the TGFB/BMP pathway, the majority mapping downstream of SMAD signaling. Testing for SMAD phosphorylation, we identify quiet but activatable TGFB signaling and cell autonomous activity of the BMP pathway resulting in the activation of the stemness regulatory transcriptional repressors ID1 and ID3. Taken together, our findings shed light on the complex miRegulatory landscape of Ewing Sarcoma pointing miR-17-92 as a key node connected to TGFB/BMP pathway.

    Topics: 3' Untranslated Regions; Bone Morphogenetic Proteins; Cell Line, Tumor; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Genetic Predisposition to Disease; Humans; MicroRNAs; Mutation; Oligonucleotide Array Sequence Analysis; Oncogene Proteins, Fusion; Proto-Oncogene Protein c-fli-1; Reverse Transcriptase Polymerase Chain Reaction; RNA-Binding Protein EWS; RNA, Long Noncoding; Sarcoma, Ewing; Sequence Analysis, RNA; Signal Transduction; Transforming Growth Factor beta

2017
Antibody-dependent cell lysis by NK cells is preserved after sarcoma-induced inhibition of NK cell cytotoxicity.
    Cancer immunology, immunotherapy : CII, 2013, Volume: 62, Issue:7

    Osteosarcoma and Ewing's sarcoma tumor cells are susceptible to IL15-induced or antibody-mediated cytolytic activity of NK cells in short-term cytotoxicity assays. When encountering the tumor environment in vivo, NK cells may be in contact with tumor cells for a prolonged time period. We explored whether a prolonged interaction with sarcoma cells can modulate the activation and cytotoxic activity of NK cells. The 40 h coculture of NK cells with sarcoma cells reversibly interfered with the IL15-induced expression of NKG2D, DNAM-1 and NKp30 and inhibited the cytolytic activity of NK cells. The inhibitory effects on receptor expression required physical contact between NK cells and sarcoma cells and were independent of TGF-β. Five days pre-incubation of NK cells with IL15 prevented the down-regulation of NKG2D and cytolytic activity in subsequent cocultures with sarcoma cells. NK cell FcγRIIIa/CD16 receptor expression and antibody-mediated cytotoxicity were not affected after the coculture. Inhibition of NK cell cytotoxicity was directly linked to the down-regulation of the respective NK cell-activating receptors. Our data demonstrate that the inhibitory effects of sarcoma cells on the cytolytic activity of NK cells do not affect the antibody-dependent cytotoxicity and can be prevented by pre-activation of NK cells with IL15. Thus, the combination of cytokine-activated NK cells and monoclonal antibody therapy may be required to improve tumor targeting and NK cell functionality in the tumor environment.

    Topics: Antibody-Dependent Cell Cytotoxicity; Antigens, Differentiation, T-Lymphocyte; Cell Line, Tumor; Coculture Techniques; Cytotoxicity, Immunologic; Humans; Interleukin-15; Killer Cells, Natural; Lymphocyte Activation; Natural Cytotoxicity Triggering Receptor 3; NK Cell Lectin-Like Receptor Subfamily K; Osteosarcoma; Receptors, IgG; Receptors, Natural Killer Cell; Sarcoma, Ewing; Transforming Growth Factor beta

2013
Critical role of endoglin in tumor cell plasticity of Ewing sarcoma and melanoma.
    Oncogene, 2011, Jan-20, Volume: 30, Issue:3

    Tumor cell plasticity enables certain types of highly malignant tumor cells to dedifferentiate and engage a plastic multipotent embryonic-like phenotype, which enables them to 'adapt' during tumor progression and escape conventional therapeutic strategies. This plastic phenotype of aggressive cancer cells enables them to express endothelial cell-specific markers and form tube-like structures, a phenotype that has been linked to aggressive behavior and poor prognosis. We demonstrate here that the transforming growth factor (TGF)-β co-receptor endoglin, an endothelial cell marker, is expressed by tumor cells and its expression correlates with tumor cell plasticity in two types of human cancer, Ewing sarcoma and melanoma. Moreover, endoglin expression was significantly associated with worse survival of Ewing sarcoma patients. Endoglin knockdown in tumor cells interferes with tumor cell plasticity and reduces invasiveness and anchorage-independent growth in vitro. Ewing sarcoma and melanoma cells with reduced endoglin levels showed reduced tumor growth in vivo. Mechanistically, we provide evidence that endoglin, while interfering with TGF-β signaling, is required for efficient bone morphogenetic protein, integrin, focal adhesion kinase and phosphoinositide-3-kinase signaling in order to maintain tumor cell plasticity. The present study delineates an important role of endoglin in tumor cell plasticity and progression of aggressive tumors.

    Topics: Animals; Antigens, CD; Base Sequence; Bone Morphogenetic Proteins; Cell Division; Cell Line, Tumor; DNA Primers; Endoglin; Female; Focal Adhesion Protein-Tyrosine Kinases; Gene Knockdown Techniques; Humans; Immunohistochemistry; Melanoma; Mice; Mice, Nude; Neoplasm Invasiveness; Phosphatidylinositol 3-Kinases; Receptors, Cell Surface; Sarcoma, Ewing; Signal Transduction; Transforming Growth Factor beta

2011
Morphoproteomic confirmation of constitutively activated mTOR, ERK, and NF-kappaB pathways in Ewing family of tumors.
    Annals of clinical and laboratory science, 2009,Spring, Volume: 39, Issue:2

    In 3 patients with the Ewing family of tumors (EFT), morphoproteomic analyses of the tumors revealed constitutive activation of the mTOR, ERK, and NF-kappaB pathways, as evidenced by: (a) expression of phosphorylated (p)-mTOR, p-p70S6K, p-ERK 1/2, and p-NF-kappaB proteins using phosphospecific immunohistochemical probes directed against the activation sites; (b) nuclear translocation of p-p70S6K, p-ERK 1/2, and p-NF-kappaB p65; and (c) correlative expression of Ki-67 and Skp2 proteins consistent with cell cycling consequent to signal transduction by these pathways of convergence. This study examines the cytogenetic and molecular correlates and provides insight into therapeutic strategies relevant to this morphoproteomic profile. Based on a literature review, these observations appear to be the first morphoproteomic study of such pathways of convergence in tumors from EFT patients.

    Topics: 12E7 Antigen; Antigens, CD; Cell Adhesion Molecules; Cell Line, Tumor; Cell Nucleus; Extracellular Signal-Regulated MAP Kinases; Flavonoids; Gene Expression Profiling; Humans; Neuroectodermal Tumors; NF-kappa B; Phosphorylation; Protein Kinases; Proteome; RNA, Messenger; Sarcoma, Ewing; Signal Transduction; TOR Serine-Threonine Kinases; Transforming Growth Factor beta; Up-Regulation

2009
EWS-FLI1, EWS-ERG, and EWS-ETV1 oncoproteins of Ewing tumor family all suppress transcription of transforming growth factor beta type II receptor gene.
    Cancer research, 2000, Mar-15, Volume: 60, Issue:6

    Ewing sarcoma-specific chromosomal translocations fuse the EWS gene to a subset of ets transcription factor family members, most commonly the FLI1 gene and less frequently ERG, ETV1, E1A-F, or FEV. These fusion proteins are thought to act as aberrant transcription factors that bind DNA through their ets DNA binding domain. Recently, we have shown (K-B. Hahm et al., Nat. Genet., 23: 222-227, 1999) that the transforming growth factor beta (TGF-beta) type II receptor (TGF-beta RII), a putative tumor suppressor gene, is a target of the EWS-FLI1 fusion protein. Here, we also examined effects of EWS-ETV1 and EWS-ERG on expression of the TGF-beta RII gene. We show that relative to the control, NIH-3T3 cell lines stably transfected with the EWS-FLI1, EWS-ERG, or EWS-ETV1 gene fusion express reduced levels of TGF-beta RII mRNA and protein, and that these cell lines have reduced TGF-beta sensitivity. Cotransfection of these fusion genes and the TGF-beta RII promoter suppresses TGF-beta RII promoter activity and also FLI1-, ERG-, or ETV1-induced promoter activity. These results indicate that transcriptional repression of TGF-beta RII is an important target of the EWS-FLI1, EWS-ERG, or EWS-ETV1 oncogene, and that EWS-ets fusion proteins may function as dominant negative forms of ets transcription factors.

    Topics: 3T3 Cells; Animals; Bone Neoplasms; DNA-Binding Proteins; Gene Expression Regulation; Humans; Luciferases; Mice; Oncogene Proteins; Oncogene Proteins, Fusion; Promoter Regions, Genetic; Protein Serine-Threonine Kinases; Proto-Oncogene Protein c-fli-1; Radioligand Assay; Receptor, Transforming Growth Factor-beta Type II; Receptors, Transforming Growth Factor beta; Recombinant Fusion Proteins; RNA-Binding Protein EWS; RNA, Messenger; Sarcoma, Ewing; Trans-Activators; Transcription Factors; Transcription, Genetic; Transcriptional Regulator ERG; Transforming Growth Factor beta; Tumor Cells, Cultured

2000
Repression of the gene encoding the TGF-beta type II receptor is a major target of the EWS-FLI1 oncoprotein.
    Nature genetics, 1999, Volume: 23, Issue:2

    Chromosomal translocations resulting in the expression of chimaeric transcription factors are frequently observed in tumour cells, and have been suggested to be a common mechanism in human carcinogenesis. Ewing sarcoma and related peripheral primitive neuroectodermal tumours share recurrent translocations that fuse the gene EWSR1 (formerly EWS) from 22q-12 to FLI1 and genes encoding other ETS transcription factors (which bind DNA through the conserved ETS domain). It has been shown that transduction of the gene EWSR1-FLI1 (encoding EWS-FLI1 protein) can transform NIH3T3 cells, and that mutants containing a deletion in either the EWS domain or the DNA-binding domain in FLI1 lose this ability. This indicates that the EWS-FLI1 fusion protein may act as an aberrant transcription factor, but the exact mechanism of oncogenesis remains unknown. Because ETS transcription factors regulate expression of TGFBR2 (encoding the TGF-beta type II receptor, TGF-beta RII; Refs 9,14), a putative tumour suppressor gene, we hypothesized that TGFBR2 may be a target of the EWS-FLI1 fusion protein. We show here that Ewing sarcoma [corrected] (ES) cell lines with the EWSR1-FLI1 fusion have reduced TGF-beta sensitivity, and that fusion-positive ES cells and primary tumours both express low or undetectable levels of TGFBR2 mRNA and protein product. Co-transfection of FLI1 and the TGFBR2 promoter induces promoter activity, whereas EWSR1-FLI1 leads to suppression of TGFBR2 promoter activity and FLI1-induced promoter activity. Introduction of EWSR1-FLI1 into cells lacking the EWSR1-FLI1 fusion suppresses TGF-beta RII expression, whereas antisense to EWSR1-FLI1 in ES cell lines positive for this gene fusion restores TGF-beta RII expression. Furthermore, introduction of normal TGF-beta RII into ES cell lines restores TGF-beta sensitivity and blocks tumorigenicity. Our results implicate TGF-beta RII as a direct target of EWS-FLI1.

    Topics: Animals; Cell Line; DNA-Binding Proteins; Gene Expression Regulation; Humans; Immunohistochemistry; Luciferases; Mice; Mice, Nude; Neuroblastoma; Oncogene Proteins, Fusion; Promoter Regions, Genetic; Protein Serine-Threonine Kinases; Proto-Oncogene Protein c-fli-1; Proto-Oncogene Proteins; Receptor, Transforming Growth Factor-beta Type II; Receptors, Transforming Growth Factor beta; Recombinant Fusion Proteins; RNA-Binding Protein EWS; RNA, Messenger; Sarcoma, Ewing; Sequence Deletion; Trans-Activators; Transcription Factors; Transfection; Transforming Growth Factor beta; Tumor Cells, Cultured

1999
Expression of bone morphogenetic proteins and receptors in sarcomas.
    Clinical orthopaedics and related research, 1999, Issue:365

    Bone morphogenetic proteins, which are capable of inducing mesenchymal tissue to form bone in mammals, have been implicated as important in normal skeletal development. The expression of bone morphogenetic proteins and their receptors were studied in 36 osteosarcoma specimens, six Ewing's sarcomas, 20 synovial sarcomas, and 20 chondrosarcomas by reverse transcriptase-polymerase chain reaction, and the findings were correlated with clinical data. Bone morphogenetic protein-2, and -4 messages were detected in most sarcoma samples. Bone morphogenetic protein-6 expression was detected in 22 of 32 osteosarcomas and seven of eight chondrosarcomas. Bone morphogenetic protein-7 and receptor IB were not detected in sarcoma samples but were detected in three osteosarcoma cell lines and one malignant fibrous histiocytoma cell line. Expression of bone morphogenetic protein receptor II was found in 25 of 36 osteosarcomas, eight of 20 chondrosarcomas, four of six Ewing's sarcomas, and 15 of 20 synovial sarcoma samples. Expression of bone morphogenetic protein type II receptor was found to correlate with metastasis in osteosarcomas, which suggests that the bone morphogenetic protein pathway may participate in tumor aggressiveness or progression. The expression of bone morphogenetic protein receptor II in metastatic synovial sarcoma and dedifferentiated chondrosarcoma lesions also supports this hypothesis. The current study showed that the ligands for bone morphogenetic protein receptors, bone morphogenetic proteins-2, -4, and -6 also are expressed in osteosarcoma and other sarcoma tissues, indicating a potential for autocrine or paracrine growth stimulation in these tumors.

    Topics: Adult; Bone Morphogenetic Protein 2; Bone Morphogenetic Protein 4; Bone Morphogenetic Protein 6; Bone Morphogenetic Protein 7; Bone Morphogenetic Protein Receptors; Bone Morphogenetic Protein Receptors, Type I; Bone Morphogenetic Protein Receptors, Type II; Bone Morphogenetic Proteins; Cell Differentiation; Chondrosarcoma; Female; Gene Expression Regulation, Neoplastic; Histiocytoma, Benign Fibrous; Humans; Male; Mesoderm; Osteogenesis; Osteosarcoma; Protein Serine-Threonine Kinases; Receptors, Cell Surface; Receptors, Growth Factor; Sarcoma; Sarcoma, Ewing; Sarcoma, Synovial; Transforming Growth Factor beta; Tumor Cells, Cultured

1999
Insulin-like growth factor I receptor-mediated circuit in Ewing's sarcoma/peripheral neuroectodermal tumor: a possible therapeutic target.
    Cancer research, 1996, Oct-15, Volume: 56, Issue:20

    The disappointingly low survival rate observed in Ewing's sarcoma (ES)/peripheral neuroectodermal tumor (PNET) despite the adoption of aggressive multimodal treatments prompted us to study the existence of autocrine circuits to be used as innovative therapeutic targets. Of the several circuits analyzed, only the insulin-like growth factor receptor (IGF-IR)-mediated loop was found to be constantly present both in cell lines and clinical samples, suggesting a role for this autocrine circuit in the pathogenesis of ES/PNET. The in vitro inhibition of the IGF-IR-mediated circuit by the specific IGF-IR binding antibody alphaIR3 suppressed the growth of ES/PNET cells by decreasing the proliferative rate and increasing apoptosis. alphaIR3 also significantly inhibited the ability of ES/PNET cells to grow in soft agar and to migrate following a chemotactic stimulus. Inactivation of the IGF-IR signaling pathway may therefore be considered as an effective therapeutic modality for patients with ES/PNET.

    Topics: Antibodies; Bone Neoplasms; Cell Movement; Humans; Insulin-Like Growth Factor I; Neuroectodermal Tumors, Primitive, Peripheral; Receptor, IGF Type 1; Sarcoma, Ewing; Transforming Growth Factor beta; Tumor Cells, Cultured

1996
Expression of transforming growth factor-beta isoforms in small round cell tumors of childhood. An immunohistochemical study.
    The American journal of pathology, 1993, Volume: 142, Issue:1

    The transforming growth factor (TGF)-betas are a highly conserved group of potent multifunctional cell regulatory proteins with variable effects on cell growth and differentiation. Most of the small round cell group of childhood tumors are thought to arise from either primitive mesenchyme or neuroectoderm and show evidence of skeletal muscle or neural differentiation, and rarely both. To investigate the possibility that the TGF-betas have a role in the growth or differentiation of these neoplasms, we used antibodies specific for peptide sequences of the three known mammalian TGF-beta isoforms (TGF-betas 1, 2, and 3) to probe for TGF-beta protein expression in a total of 49 cases. TGF-beta 1 immunoreactivity was present in 16/17 (94%) of rhabdomyosarcomas, and the staining intensity was usually strong. TGF-beta 1 was also present in three of three ectomesenchymomas. In contrast, TGF-beta 1 was absent in all but one out of nine poorly differentiated neuroblastomas. Differentiating neuronal cells of ganglioneuroblastomas, however, were strongly positive for TGF-beta 1. Ewing's sarcomas and peripheral primitive neuroectodermal tumors had a less consistent, but usually positive, staining pattern. TGF-beta 3 staining patterns were very similar to those of TGF-beta 1. TGF-beta 2 immunoreactivity was only rarely detected in this group of tumors. The results suggest different roles for TGF-betas 1 and 3 in neuroblastoma and rhabdomyosarcoma. Expression of TGF-betas 1 and 3 is associated with neuronal differentiation of neuroblastoma. In contrast, these proteins may promote the growth of rhabdomyosarcoma by suppressing differentiation.

    Topics: Adolescent; Adult; Antibodies, Monoclonal; Carcinoma, Small Cell; Child; Child, Preschool; Ganglioneuroma; Humans; Infant; Mesenchymoma; Molecular Probes; Neuroblastoma; Neurosecretory Systems; Rhabdomyosarcoma; Sarcoma, Ewing; Transforming Growth Factor beta

1993
Modulation of hematopoietic colony formation of stem cells in peripheral blood by anti-TGF-beta in patients with severe immunosuppression.
    Klinische Wochenschrift, 1990, Dec-30, Volume: 69, Issue:24

    The influence of transforming growth factor-beta (TGF-beta) on hematopoiesis has been evaluated by adding blocking antibodies against TGF-beta to colony forming assays (CFU-c). When optimum concentrations of recombinant growth factors, granulocyte-macrophage colony stimulating factor (GM-CSF), and interleukin-3 (IL-3) were added to stem cells from the peripheral blood of healthy individuals and certain patients with tumors or HIV infection, the anti-TGF-beta capable of blocking 5 ng/ml of active TGF-beta had no significant influence on erythroid or myeloid colony formation. However, in certain immunosuppressed individuals, anti-TGF-beta resulted in a significant decrease of erythroid colony formation and slight suppression of myeloid colony formation. The significant inhibition of hematopoiesis by plasma of HIV patients could be due to the presence of active forms of TGF-beta. The results of the blocking experiments are consistent with the concept that TGF-beta in low concentrations is essential for erythropoiesis and myelopoiesis but that higher levels of TGF-beta primarily inhibit erythropoiesis in vitro. TGF-beta serves as a coordinating factor when efficient recruitment of granulocytes and monocytes is more essential than erythropoiesis and stem cell growth.

    Topics: Colony-Forming Units Assay; Fibrosarcoma; Hematopoietic Stem Cells; HIV Seropositivity; Humans; Immunocompromised Host; Sarcoma, Ewing; Transforming Growth Factor beta

1990