We have previously identified Ertredin (3-(2-amino-5-bromophenyl) quinoxalin-2(1H)-one) as a compound that suppresses 3D spheroid formation and tumorigenesis in NIH3T3 cells induced by variant III () transduction. One of its targets has been shown to be NDUFA12 (NADH Dehydrogenase (Ubiquinone) 1 Alpha Subcomplex Subunit 12), a component protein of oxidative phosphorylation complex I. In this report, we compared the growth inhibitory activity of Ertredin with its methylated analogue 7MeERT (3-(2-amino-5-bromophenyl)-7-methylquinoxalin-2(1H)-one) on human cancer cells.
View Article and Find Full Text PDFAcute lung injury (ALI) is characterized by hyperinflammation followed by vascular leakage and respiratory failure. Vascular endothelial growth factor (VEGF)-A is critical for capillary permeability; however, the role of VEGF receptor 1 (VEGFR1) signaling in ALI progression remains unclear. Here, we show that deletion of VEGFR1 tyrosine kinase (TK) signaling in mice exacerbates lipopolysaccharide (LPS)-induced ALI as evidenced by excessive pro-inflammatory cytokine production and interleukin(IL)-1β-producing neutrophil recruitment to inflamed lung tissues.
View Article and Find Full Text PDFMany attempts have been made to develop new agents that target EGFR mutants or regulate downstream factors in various cancers. Cell-based screening showed that a natural small molecule, Ertredin, inhibited the growth of EGFRvIII mutant cancer cells. Previous studies have shown that Ertredin effectively inhibits anchorage-independent 3D growth of sphere-forming cells transfected with EGFRvIII mutant cDNA.
View Article and Find Full Text PDFBone marrow-derived cells (BMDCs) infiltrate hypoxic tumors at a pre-angiogenic state and differentiate into mature macrophages, thereby inducing pro-tumorigenic immunity. A critical factor regulating this differentiation is activation of SREBP2-a well-known transcription factor participating in tumorigenesis progression-through unknown cellular mechanisms. Here, we show that hypoxia-induced Golgi disassembly and Golgi-ER fusion in monocytic myeloid cells result in nuclear translocation and activation of SREBP2 in a SCAP-independent manner.
View Article and Find Full Text PDFEndothelial phospholipase Cγ (PLCγ) is essential for vascular development; however, its role in healthy, mature, or pathological vessels is unexplored. Here, we show that PLCγ was prominently expressed in vessels of several human cancer forms, notably in renal cell carcinoma (RCC). High PLCγ expression in clear cell RCC correlated with angiogenic activity and poor prognosis, while low expression correlated with immune cell activation.
View Article and Find Full Text PDFThe Fms-like tyrosine kinase-1 (FLT1) gene is expressed in various types of cells, including vascular endothelial cells and placental trophoblasts, and regulates angiogenesis, inflammation, and pregnancy. However, the basal transcriptional machinery of FLT1 is still not well understood. In this study, we first examined FLT1 promoter activity in three different types of cells, that is, trophoblast-derived cells, vascular endothelial-related cells, and HEK293 cells, using plasmid-based luciferase reporter assays, and showed that a cAMP-response element (CRE) and an ETS-binding site (EBS) are important for FLT1 expression in all cell types.
View Article and Find Full Text PDFIntraretinal hyperreflective foci (HRF) are significant biomarkers for diabetic macular edema. However, HRF at the vitreoretinal interface (VRI) have not been examined in diabetic retinopathy (DR). A prospective observational clinical study with 162 consecutive eyes using OCT imaging showed significantly increased HRF at the VRI during DR progression (P < 0.
View Article and Find Full Text PDFPlacental hypoxia and increased levels of maternal blood anti-angiogenic protein, soluble fms-like tyrosine kinase-1 (sFLT1), are associated with the pathogenesis of pre-eclampsia. We have demonstrated that hypoxia-inducible factor (HIF)-2α mediates the upregulation of the hypoxia-induced FLT1 gene in trophoblasts and their cell lines. Here, we investigated the involvement of HIF-1β, which acts as a dimerization partner for HIF-α, in the upregulation of the FLT1 gene via hypoxia.
View Article and Find Full Text PDFIn normal pregnancy, the soluble form of FMS-like tyrosine kinase-1 (sFLT1)/ vascular endothelial growth factor receptor-1 (sVEGFR-1), a VEGF-trapping protein, is expressed in trophoblasts of the placenta, suggesting that it plays an important role in the physiological barrier between fetal and maternal angiogenesis, when stimulated with VEGF-A. In pathological conditions such as preeclampsia (PE), sFLT1 protein is abnormally overexpressed in trophoblasts and secreted into the serum, which could cause hypertension and proteinuria on the maternal side and growth retardation on the fetal side. Detection of an abnormal increase in serum sFLT1 during the early to middle stages of PE is essential for proper initiation of medical care.
View Article and Find Full Text PDFA series of analogs of vegfrecine, a natural quinone vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitor, was synthesized via oxidative amination of 2,5-dihydroxybenzamide with functionalized arylamine followed by ammonolysis and substitution of the quinone ring. The inhibitory activities of the analogs against the VEGFR-1 and -2 tyrosine kinases were assayed in vitro with the aim to identify a compound suitable to treat cancer and inflammatory diseases. Alterations of the functionality of the phenyl group, substitution of the quinone ring, and oxidative cyclization of the 1-carboxamide-2-aminoquinone moiety to form an isoxazole quinone ring were examined.
View Article and Find Full Text PDFAlong with blood vessels, lymphatic vessels play an important role in the circulation of body fluid and recruitment of immune cells. Postnatal lymphangiogenesis commonly occurs from preexisting lymphatic vessels by sprouting, which is induced by lymphangiogenic factors such as vascular endothelial growth factor C (VEGF-C). However, the key signals and cell types that stimulate pathological lymphangiogenesis, such as human cystic lymphangioma, are less well known.
View Article and Find Full Text PDFLymphangiogenesis is related to the growth of endometriosis. Here, we examined whether vascular endothelial growth factor (VEGF) receptor 1 (VEGFR1) signaling plays a role in lymphangiogenesis during endometriosis. Endometrial fragments from wild-type (WT) mice transplanted into the peritoneal wall of host WT mice (WT→WT) developed well and displayed enhanced lymphangiogenesis associated with increases in mRNA levels of VEGF-C and VEGF-D.
View Article and Find Full Text PDFBackground: Soluble Fms-like tyrosine kinase-1 (sFLT1) as an anti-angiogenic factor is abundantly expressed in placental trophoblasts. Choriocarcinoma, a malignant tumor derived from trophoblasts, is known to be highly angiogenic and metastatic. However, the molecular mechanism underlying angiogenesis in choriocarcinoma pathogenesis remains unclear.
View Article and Find Full Text PDFAlthough degenerative disc disease (DDD) and related low back pain (LBP) are growing public health problems, the underlying disease mechanisms remain unclear. An increase in the vascular endothelial growth factor (VEGF) levels in DDD has been reported. This study aimed to examine the role of VEGF receptors (VEGFRs) in DDD, using a mouse model of DDD.
View Article and Find Full Text PDFTolerance to severe tumor microenvironments, including hypoxia and nutrient starvation, is a common feature of aggressive cancer cells and can be targeted. However, metabolic alterations that support cancer cells upon nutrient starvation are not well understood. Here, by comprehensive metabolome analyses, we show that glutamine deprivation leads to phosphoethanolamine (PEtn) accumulation in cancer cells via the downregulation of PEtn cytidylyltransferase (PCYT2), a rate-limiting enzyme of phosphatidylethanolamine biosynthesis.
View Article and Find Full Text PDFExaggerated signaling by vascular endothelial growth factor (VEGF)-A and its receptor, VEGFR2, in pathologies results in poor vessel function. Still, pharmacological suppression of VEGFA/VEGFR2 may aggravate disease. Delineating VEGFR2 signaling in vivo provides strategies for suppression of specific VEGFR2-induced pathways.
View Article and Find Full Text PDFBackground: Idiopathic pulmonary fibrosis (IPF) is a lethal lung disease with a poor prognosis. Fibroblast proliferation amplifies extracellular matrix deposition and increases angiogenesis. Vascular endothelial growth factor (VEGF) is one of the most potent angiogenic factors.
View Article and Find Full Text PDFAngiogenesis is critical in maintenance of endometrial tissues. Here, we examined the role of VEGF receptor 1 (VEGFR1) signaling in angiogenesis and tissue growth in an endometriosis model. Endometrial fragments were implanted into the peritoneal wall of mice, and endometrial tissue growth and microvessel density (MVD) were determined.
View Article and Find Full Text PDFBackground: Ulcerative Colitis (UC) is an inflammatory bowel disease that affects the colon. The development of UC is regulated by immune cells. Previously, we showed that vascular endothelial growth factor receptor 1 (VEGFR1) tyrosine kinase (TK) signaling induces healing of mucosal damage by recruiting VEGFR1 cells appear to be lineage monocyte cells.
View Article and Find Full Text PDFPlacental hypoxia and elevated levels of circulating soluble Fms-like tyrosine kinase-1 (sFlt-1), an anti-angiogenic factor, are closely related to the pathogenesis of preeclampsia. Although sFlt-1 secretion from the placental trophoblasts is increased under hypoxic conditions, the underlying molecular mechanism remains unclear. Previously, an authentic hypoxia response element in the Flt-1 gene promoter was shown to be a potential binding site for hypoxia-inducible factors (HIFs).
View Article and Find Full Text PDFPericyte desorption from retinal blood vessels and subsequent vascular abnormalities are the pathogenesis of diabetic retinopathy (DR). Although the involvement of abnormal signals including platelet-derived growth factor receptor-β (PDGFRβ) and vascular endothelial growth factor-A (VEGF-A) have been hypothesized in DR, the mechanisms that underlie this processes are largely unknown. Here, novel retinopathy mouse model (N-PRβ-KO) was developed with conditional Pdgfrb gene deletion by Nestin promoter-driven Cre recombinase (Nestin-Cre) that consistently reproduced through early non-proliferative to late proliferative DR pathologies.
View Article and Find Full Text PDFEctodomain shedding and regulated intracellular proteolysis can determine the fate or function of cell surface proteins. Fms-related tyrosine kinase (FLT) or VEGF receptor 1 is a high-affinity cell surface VEGF-A receptor tyrosine kinase that is constitutively cleaved to release an NH-terminal VEGF-A binding ectodomain that, once shed, can antagonize the effects of VEGF-A in the extracellular milieu. We evaluated the effect of VEGF-A on FLT1 cleavage in native cells and in transient and stable expression systems.
View Article and Find Full Text PDFVascular endothelial growth factor (VEGF)-A facilitates wound healing. VEGF-A binds to VEGF receptor 1 (VEGFR1) and VEGFR2 and induces wound healing through the receptor's tyrosine kinase (TK) domain. During blood flow recovery and lung regeneration, expression of VEGFR1 is elevated.
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