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Feng, J.-X.

Publications and source records attributed to Feng, J.-X..

3 recordsLinked to original sources

Single-cell lineage tracing identifies hemogenic endothelial cells in the adult mouse bone marrow

During mouse development, hematopoietic stem and progenitor cells (HSPC) originate from hemogenic endothelial cells (ECs) through a process of endothelial-to-hematopoietic transition. These HSPC are thought to fully sustain adult hematopoiesis. However, it remains unknown whether adult ECs retain hemogenic potential. Here we used in vivo genetic lineage tracking at population and single-cell (sc) levels, scRNA sequencing, and bone marrow transplantation to detect hemogenic ECs in adult mice. We identify and characterize bone marrow-resident, adult Cdh5/VE-Cadherin+ ECs that produce hematopoietic cell-progeny in vitro and in mice. These adult hemogenic ECs and their hematopoietic cell progeny give rise to hematopoietic cells following adoptive transfer into adult mice. Furthermore, blood cells generated from adult and developmental ECs comparably home to peripheral tissues, where they similarly contribute to inflammatory responses. Thus, our results identify previously unrecognized bone marrow-derived adult hemogenic ECs that generate HSPC and functional mature blood cells.

cell biology↗

Bone marrow hemogenic endothelial cells contribute multilineage hematopoietic progenitors in adult mice

During development, hematopoietic stem/progenitor cells (HSPCs) originate from a subset of hemogenic endothelial cells (ECs) through a process of endothelial-to-hematopoietic transition (EHT). This process is temporally restricted to short developmental windows and generates HSPC with distinct capabilities for hematopoiesis. Although it is generally thought that adult hematopoiesis is sustained by HSCs derived from hemogenic endothelium during development, some observations point to EHT persistence in the late fetus/perinatally. Here we use lineage tracking and bioinformatics analysis to assess the presence of hemogenic endothelial cells in the adult mouse. Our analysis identifies a subset of bone marrow-resident adult endothelial cells, characterized by the expression of VE-Cadherin and the transcription factor RUNX1, that produce CD45+ hematopoietic cells. This EHT generates hematopoietic progenitors, and mature myeloid and lymphoid cells in the adult mouse. Our results reveal the identification of a distinct source of adult blood.

cell biology↗

Targeting the SHP2 phosphatase promotes vascular damage and inhibition of tumor growth

The tyrosine phosphatase SHP2 is oncogenic in cancers driven by receptor-tyrosine-kinases, and SHP2 inhibition reduces tumor growth. Here, we report that SHP2 is an essential promoter of endothelial cell survival and growth in the remodeling tumor vasculature. Using genetic and chemical approaches to inhibit SHP2 activity in endothelial cells, we show that SHP2 inhibits pro-apoptotic STAT3 and stimulates proliferative ERK1/2 signaling. Systemic SHP2 inhibition in mice bearing tumors selected for SHP2-independent tumor-cell growth, promotes degeneration of the tumor vasculature and blood extravasation; reduces tumor vascularity and blood perfusion; and increases tumor hypoxia and necrosis. Reduction of tumor growth ensues, independent of SHP2 targeting in the tumor cells, blocking immune checkpoints or recruiting anti-tumor macrophages. We also show that inhibiting the Angiopoietin/TIE2/AKT cascade magnifies the vascular and anti-tumor effects of SHP2 inhibition by blocking tumor endothelial AKT signaling, not a target of SHP2. Since the SHP2 and Ang2/TIE2 pathways are active in vascular endothelial cells of human melanoma and colon carcinoma, SHP2 inhibitors alone or with Ang2/Tie2 inhibitors hold promise to effectively target the tumor endothelium.

cancer biology↗