Similar Datasets
Project description:Erythropoiesis is a crucial part in hematopoietic system, while facing disruptions from various diseases conditions. Anemia and blood shortages has become global challenges, with current finite pharmacological options like EPO or glucocorticoids having limitations, especially in genetic anemias like Diamond-Blackfan anemia (DBA), calling for novel candidates in stimulating the erythropoiesis. We designed the primary human hematopoietic stem and progenitor cells (HSPCs) chemicals screening system in erythropoiesis and unexpectedly discovered a BRAF inhibitor, effectively against BRAFV600E mutant cancers, delaying erythroid differentiation while promoting progenitors’ proliferation. Further research demonstrated its efficacy in cytokine-restricted conditions and in samples from erythroid disorder patients. Mechanistically, BRAF inhibitors paradoxically activated the RAF-MEK-ERK/MAPK pathway. Unlike oncogenic BRAFV600E impaired hematopoiesis and erythropoiesis via AP-1 hyperactivation, BRAF inhibitors minimally affected HSPCs self-renewal and differentiation. In vivo studies further exhibited BRAF inhibitors' potential to enhance human hematopoiesis and erythropoiesis in severe immunodeficient mouse models and alleviate anemia symptoms in Rpl11 haploinsufficiency DBA models and other anemia models. This discovery sheds light on the MAPK pathway's role in hematopoiesis, making BRAF inhibitors a novel clinically therapeutic choice in improving hematopoietic reconstitution and the recovery of anemias like DBA.
2024-12-03 | GSE261117 | GEO
Project description:Erythropoiesis is a crucial part in hematopoietic system, while facing disruptions from various diseases conditions. Anemia and blood shortages has become global challenges, with current finite pharmacological options like EPO or glucocorticoids having limitations, especially in genetic anemias like Diamond-Blackfan anemia (DBA), calling for novel candidates in stimulating the erythropoiesis. We designed the primary human hematopoietic stem and progenitor cells (HSPCs) chemicals screening system in erythropoiesis and unexpectedly discovered a BRAF inhibitor, effectively against BRAFV600E mutant cancers, delaying erythroid differentiation while promoting progenitors’ proliferation. Further research demonstrated its efficacy in cytokine-restricted conditions and in samples from erythroid disorder patients. Mechanistically, BRAF inhibitors paradoxically activated the RAF-MEK-ERK/MAPK pathway. Unlike oncogenic BRAFV600E impaired hematopoiesis and erythropoiesis via AP-1 hyperactivation, BRAF inhibitors minimally affected HSPCs self-renewal and differentiation. In vivo studies further exhibited BRAF inhibitors' potential to enhance human hematopoiesis and erythropoiesis in severe immunodeficient mouse models and alleviate anemia symptoms in Rpl11 haploinsufficiency DBA models and other anemia models. This discovery sheds light on the MAPK pathway's role in hematopoiesis, making BRAF inhibitors a novel clinically therapeutic choice in improving hematopoietic reconstitution and the recovery of anemias like DBA.
2024-12-03 | GSE261118 | GEO
Project description:BRAF inhibitors promote erythropoiesis and hematopoiesis via paradoxical MAPK activation
| PRJNA1085310 | ENA
Project description:BRAF inhibitors promote erythropoiesis and hematopoiesis via paradoxical MAPK activation (ATAC-Seq)
| PRJNA1085317 | ENA
Project description:BRAF inhibitors promote erythropoiesis and hematopoiesis via paradoxical MAPK activation (RNA-Seq)
| PRJNA1085318 | ENA
Project description:Erythropoiesis is a crucial process in hematopoiesis, yet it remains highly susceptible to disruption by various diseases, which significantly contribute to the global challenges of anemia and blood shortages. Current treatments like erythropoietin (EPO) or glucocorticoids often fall short, especially for hereditary anemias such as Diamond-Blackfan anemia (DBA). To uncover new erythropoiesis-stimulating agents, we devised a screening system using primary human hematopoietic stem and progenitor cells (HSPCs). We discovered that BRAF inhibitors (BRAFi), commonly used to treat BRAFV600E melanoma, can unexpectedly and effectively promote progenitor cell proliferation by temporarily delaying erythroid differentiation. Notably, these inhibitors exhibited pronounced efficacy even under cytokine-restricted conditions and in patient samples of DBA. Mechanistically, although these BRAFi inhibit the MAPK cascade in BRAFV600E mutant cells, they paradoxically act as amplifiers in wild-type BRAF cells, potently enhancing the cascade. Furthermore, we found that while the oncogenic BRAFV600E mutation disrupts hematopoiesis and erythropoiesis through AP-1 hyperactivation, BRAFi minimally impact HSPC self-renewal and differentiation. In vivo studies have shown that BRAFi can enhance human hematopoiesis and erythropoiesis in severe immunodeficient mouse models and alleviate anemia in the Rpl11 haploinsufficiency DBA model, as well as other relevant anemia models. This discovery underscores the role of the MAPK pathway in hematopoiesis and positions BRAFi as a promising therapeutic option for improving hematopoietic reconstitution and treating anemias, including DBA.
2024-12-02 | GSE221242 | GEO
Project description:Erythropoiesis is a crucial part in hematopoietic system, while facing disruptions from various diseases conditions. Anemia and blood shortages has become global challenges, with current finite pharmacological options like EPO or glucocorticoids having limitations, especially in genetic anemias like Diamond-Blackfan anemia (DBA), calling for novel candidates in stimulating the erythropoiesis. We designed the primary human hematopoietic stem and progenitor cells (HSPCs) chemicals screening system in erythropoiesis and unexpectedly discovered a BRAF inhibitor, effectively against BRAFV600E mutant cancers, delaying erythroid differentiation while promoting progenitors’ proliferation. Further research demonstrated its efficacy in cytokine-restricted conditions and in samples from erythroid disorder patients. Mechanistically, BRAF inhibitors paradoxically activated the RAF-MEK-ERK/MAPK pathway. Unlike oncogenic BRAFV600E impaired hematopoiesis and erythropoiesis via AP-1 hyperactivation, BRAF inhibitors minimally affected HSPCs self-renewal and differentiation. In vivo studies further exhibited BRAF inhibitors' potential to enhance human hematopoiesis and erythropoiesis in severe immunodeficient mouse models and alleviate anemia symptoms in Rpl11 haploinsufficiency DBA models and other anemia models. This discovery sheds light on the MAPK pathway's role in hematopoiesis, making BRAF inhibitors a novel clinically therapeutic choice in improving hematopoietic reconstitution and the recovery of anemias like DBA.
2024-09-09 | PXD055730 |
Project description:BRAF inhibitors are highly effective therapies for the treatment of BRAF(V600)-mutated melanoma, with the main toxicity being a variety of hyperproliferative skin conditions due to paradoxical activation of the mitogen-activated protein kinase (MAPK) pathway in BRAF wild-type cells. Most of these hyperproliferative skin changes improve when a MEK inhibitor is co-administered, as it blocks paradoxical MAPK activation. Here we show how the BRAF inhibitor vemurafenib accelerates skin wound healing by inducing the proliferation and migration of human keratinocytes through extracellular signal-regulated kinase (ERK) phosphorylation and cell cycle progression. Topical treatment with vemurafenib in two wound-healing mice models accelerates cutaneous wound healing through paradoxical MAPK activation; addition of a mitogen-activated protein kinase kinase (MEK) inhibitor reverses the benefit of vemurafenib-accelerated wound healing. The same dosing regimen of topical BRAF inhibitor does not increase the incidence of cutaneous squamous cell carcinomas in mice. Therefore, topical BRAF inhibitors may have clinical applications in accelerating the healing of skin wounds.
| S-EPMC4974650 | biostudies-literature
Project description:BRAF inhibitors enhance erythropoiesis and treat anemia through paradoxical activation of MAPK signaling
| PRJNA913585 | ENA
Project description:The type II class of RAF inhibitors currently in clinical trials paradoxically activate BRAF at subsaturating concentrations. Activation is mediated by induction of BRAF dimers, but why activation rather than inhibition occurs remains unclear. Using biophysical methods tracking BRAF dimerization and conformation we built an allosteric model of inhibitor-induced dimerization that resolves the allosteric contributions of inhibitor binding to the two active sites of the dimer, revealing key differences between type I and type II RAF inhibitors. For type II inhibitors the allosteric coupling between inhibitor binding and BRAF dimerization is distributed asymmetrically across the two dimer binding sites, with binding to the first site dominating the allostery. This asymmetry results in efficient and selective induction of dimers with one inhibited and one catalytically active subunit. Our allosteric models quantitatively account for paradoxical activation data measured for 11 RAF inhibitors. Unlike type II inhibitors, type I inhibitors lack allosteric asymmetry and do not activate BRAF homodimers. Finally, NMR data reveal that BRAF homodimers are dynamically asymmetric with only one of the subunits locked in the active αC-in state. This provides a structural mechanism for how binding of only a single αC-in inhibitor molecule can induce potent BRAF dimerization and activation.
| S-EPMC10153139 | biostudies-literature