Search

Pro-inflammatory signaling is a hallmark feature of human cancer, including in myeloproliferative neoplasms (MPNs), most notably myelofibrosis (MF). Dysregulated inflammatory signaling contributes to fibrotic progression in MF; however, the individual cytokine mediators elicited by malignant MPN cells to promote collagen-producing fibrosis and disease evolution remain yet to be fully elucidated. Previously we identified a critical role for combined constitutive JAK/STAT and aberrant NF-kB pro-inflammatory signaling in myelofibrosis development. Using single-cell transcriptional and cytokine-secretion studies of primary MF patient cells and the hMPLW515L murine model of myelofibrosis, we extend this previous work and delineate the role of CXCL8/CXCR2 signaling in MF pathogenesis and bone marrow fibrosis progression. MF patient hematopoietic stem/progenitor cells are enriched for a CXCL8/CXCR2 gene signature and display enhanced proliferation and fitness in response to exogenous CXCL8 ligand in vitro. Genetic deletion of Cxcr2 in the hMPLW515L adoptive transfer model abrogates fibrosis and extends overall survival, and pharmacologic inhibition of the CXCR1/2 pathway improves hematologic parameters, attenuates bone marrow fibrosis, and synergizes with JAK inhibitor therapy. Our mechanistic insights provide a rationale for therapeutic targeting of the CXCL8/CXCR2 pathway in MF patients.

SUMMARYPro-inflammatory signaling is a hallmark feature of human cancer, including in myeloproliferative neoplasms (MPNs), most notably myelofibrosis (MF). Dysregulated inflammatory signaling contributes to fibrotic progression in MF; however, the individual cytokine mediators elicited by malignant MPN cells to promote collagen-producing fibrosis and disease evolution remain yet to be fully elucidated. Previously we identified a critical role for combined constitutive JAK/STAT and aberrant NF-κB pro-inflammatory signaling in myelofibrosis development. Using single-cell transcriptional and cytokine-secretion studies of primary MF patient cells and two separate murine models of myelofibrosis, we extend this previous work and delineate the role of CXCL8/CXCR2 signaling in MF pathogenesis and bone marrow fibrosis progression. MF patient hematopoietic stem/progenitor cells are enriched in a CXCL8/CXCR2 gene signature and display dose-dependent proliferation and fitness in response to exogenous CXCL8 ligand in vitro. Genetic deletion of Cxcr2 in the hMPLW515L adoptive transfer model abrogates fibrosis and extends overall survival, and pharmacologic inhibition of the CXCR1/2 pathway improves hematologic parameters, attenuates bone marrow fibrosis, and synergizes with JAK inhibitor therapy. Our mechanistic insights provide a rationale for therapeutic targeting of the CXCL8/CXCR2 pathway in MF patients at risk for continued fibrotic progression.

Current therapy for myelofibrosis (MF) results in a limited prolongation of patient survival. In order to improve treatment outcomes, we developed a strategy to effectively deplete MF hematopoietic stem/progenitor cells (HSPCs). In the present study, an imipridone, ONC201, was combined with RG7112, an antagonist of MDM2, a p53 negative regulator, to activate downstream events of the p53 and TNF-related apoptosis-inducing ligand (TRAIL)/death receptor (DR) pathways. As compared to treatment with the individual drugs, the combination of ONC201 and RG7112 promoted greater degrees of apoptosis of MF CD34+ cells through activation of both p53-dependent and -independent pathways. Importantly, treatment with ONC201-RG7112 not only decreased the number of JAK2V617F+ and calreticulin mutated colonies assayed from MF CD34+ cells, but allowed for the persistence or appearance of JAK2 wild type colonies. Treatment with ONC201 combined with RG7112 could be a potentially effective strategy for treating MF patients.

This article presents a framework for the implementation of BIM in organizations on a strategic level in Egypt. Earlier analysis of the Egyptian construction market was carried to measure the BIM maturity of organizations. The assessment was required to study where the Egyptian market stands when it comes to BIM knowledge. This was done as a prior step to create an implementation plan. After aligning BIM goals with the current BIM status, recommendations are highlighted in order to create a roadmap for BIM implementation in organizations. A modeling tool was selected to represent the created roadmap. The modeling tool was selected in order to facilitate the implementation of the roadmap in the Egyptian construction industry. The model is created using Integrated Definition (IDEF0) diagrams as a functional modeling tool. The model is made accessible for industry practitioners to use it as a prior step for BIM implementation planning.