Project description:Increased levels of hypoxia and hypoxia inducible factor 1α (HIF-1α) in human sarcomas correlate with tumor progression and radiation resistance. Prolonged anti-angiogenic therapy of tumors can delay tumor growth but may also increase hypoxia and HIF-1α activity. In our recent clinical trial, treatment with the anti-vascular endothelial growth factor A (VEGF-A) antibody, bevacizumab, followed by a combination of bevacizumab and radiation led to near complete necrosis in nearly half of sarcomas. Gene set enrichment analysis of microarrays from pre-treatment biopsies found the Gene Ontology category “Response to hypoxia” was upregulated in poor responders, and hierarchical clustering based on 140 hypoxia-responsive genes separated poor responders from good responders. The most commonly used chemotherapeutic drug for sarcomas, doxorubicin (Dox), was recently found to block HIF-1α binding to DNA at low metronomic doses. We thus examined Dox treatment in 4 sarcoma cell lines, and found Dox at low concentrations (1-10 uM) blocked HIF-1α induction of VEGF-A by 84-97%, while inhibition of other HIF-1α-target genes including CA9, c-Met and FOXM1 was variable. HT1080 sarcoma xenografts had increased hypoxia and/or HIF-1α activity with increasing tumor size and with anti-VEGF receptor antibody (DC101) treatment. Combining DC101 and metronomic Dox had a synergistic effect in suppressing growth of HT1080 xenografts, primarily via induction of tumor endothelial cell apoptosis. In conclusion, sarcomas respond to increased hypoxia by expressing HIF-1α-target genes which may promote resistance to anti-angiogenic and other therapies. Metronomic Dox can block HIF-1α activation of target genes and works synergistically with anti-VEGF therapy to inhibit sarcomas. Pre-treatment biopsies were collected from 16 human sarcoma. The gene expression analysis was performed using Illumina platform.
Project description:Increased levels of hypoxia and hypoxia inducible factor 1α (HIF-1α) in human sarcomas correlate with tumor progression and radiation resistance. Prolonged anti-angiogenic therapy of tumors can delay tumor growth but may also increase hypoxia and HIF-1α activity. In our recent clinical trial, treatment with the anti-vascular endothelial growth factor A (VEGF-A) antibody, bevacizumab, followed by a combination of bevacizumab and radiation led to near complete necrosis in nearly half of sarcomas. Gene set enrichment analysis of microarrays from pre-treatment biopsies found the Gene Ontology category “Response to hypoxia” was upregulated in poor responders, and hierarchical clustering based on 140 hypoxia-responsive genes separated poor responders from good responders. The most commonly used chemotherapeutic drug for sarcomas, doxorubicin (Dox), was recently found to block HIF-1α binding to DNA at low metronomic doses. We thus examined Dox treatment in 4 sarcoma cell lines, and found Dox at low concentrations (1-10 uM) blocked HIF-1α induction of VEGF-A by 84-97%, while inhibition of other HIF-1α-target genes including CA9, c-Met and FOXM1 was variable. HT1080 sarcoma xenografts had increased hypoxia and/or HIF-1α activity with increasing tumor size and with anti-VEGF receptor antibody (DC101) treatment. Combining DC101 and metronomic Dox had a synergistic effect in suppressing growth of HT1080 xenografts, primarily via induction of tumor endothelial cell apoptosis. In conclusion, sarcomas respond to increased hypoxia by expressing HIF-1α-target genes which may promote resistance to anti-angiogenic and other therapies. Metronomic Dox can block HIF-1α activation of target genes and works synergistically with anti-VEGF therapy to inhibit sarcomas.
Project description:Bacterial meningitis is a deadly disease most commonly caused by Streptococcus pneumoniae that leads to severe neurological sequelae including cerebral edema, seizures, stroke, and mortality when untreated. Meningitis is initiated by the transfer of S. pneumoniae from hematogenous source into the brain across the blood-brain barrier (BBB); the mechanisms however are still poorly understood. Current treatment strategies include adjuvant dexamethasone therapy for cerebral edema, the prime reason for neurological complications and mortality, which is followed up by antibiotics. The success of corticosteroids is however inconclusive, necessitating the development of new therapies for controlling cerebral edema. We have previously shown a general activation of hypoxia inducible factor (HIF-1α) in bacterial infections, we therefore hypothesized that HIF-1α, via induction of vascular endothelial growth factor (VEGF) is critically involved in the transmigration of pathogens across the BBB. In human and murine meningitis brain samples, HIF-1 activation was observed by immunohistochemistry. HIF-1α/VEGF expression and permeability was therefore analyzed in vitro in infected brain endothelial cells (ECs). Localization of S. pneumoniae in brain ECs from mouse/human sources was visualized in vitro and in vivo by confocal, super-resolution, and electron microscopy. S. pneumoniae infection in brain ECs resulted in upregulation of HIF-1α/VEGF by Western blotting and qRT-PCR that was associated with increased paracellular permeability, which was supported by bacterial localization at cell-cell junctions. RNA sequencing of brain microvessels from hematogenously infected mice with increased permeability and S. pneumoniae deposition in the brain showed upregulation of genes in HIF-1α/VEGF pathway. Inhibition of HIF-1α with echinomycin, siRNA in bEnd5 cells and by using primary brain ECs from HIF-1α KO mice revealed a reduced endothelial permeability and transmigration of S. pneumoniae. We thus demonstrate a critical role for HIF-1α/VEGF in transmigration of S. pneumoniae across the BBB and propose targeting this pathway to prevent BBB dysfunction in infections.
Project description:In multiple myeloma (MM), hypoxia-inducible transcription factor-1 (HIF-1) is overexpressed in the MM cells of the hypoxic bone marrow (BM) microenvironment. Herein, we explored in MM cells the in vitro and in vivo effects of persistent HIF-1 inhibition by expression of a lentivirus shRNA pool on proliferation, survival and transcriptional and pro-angiogenic profiles. Among the significantly modulated genes (326 and 361 genes in hypoxic and normoxic condition, respectively), we found that HIF-1 inhibition in the human myeloma cell line JJN3 downregulates the pro-angiogenic molecules VEGF, IL8, IL10, CCL2, CCL5, and MMP9. Interestingly, several pro-osteoclastogenic cytokines were also inhibited, such as IL-7 and CCL3/MIP-1. The effect of HIF-1 inhibition was assessed in vivo in NOD/SCID mice both in subcutaneous and intratibial models, indicating in either case a dramatic reduction of weight and volume of the tumor burden as a consequence of HIF-1 knockdown. Moreover, a significant reduction of the number of vessels per field and VEGF immunostaining were observed. Finally, in the intra-tibial experiments, HIF-1 inhibition significantly blocks JJN3-induced bone destruction. Overall, our data indicate that HIF-1 suppression in MM cells significantly blocks MM-induced angiogenesis and reduces both tumor burden and bone destruction in vivo, strongly indicating HIF-1 as an emerging therapeutic target in MM. The transcriptional profiles on JJN3 transduced with shRNA anti-HIF-1 (JJN3-anti-HIF-1), as compared to those infected with the control vector pLKO.1 (JJN3-pLKO.1), have been analyzed either in hypoxic or normoxic conditions. To perform gene expression profiles, total RNA was purified using the RNeasy Total RNA Isolation Kit (Qiagen, Valencia, CA). Preparation of biotin-labeled cRNA, hybridization to GeneChip Human Genome U133 Plus 2.0 Arrays and scanning (GeneChip¨ Scanner 3000 7G, Affymetrix Inc.) were performed according to manufacturer's protocols.
Project description:An immunosuppressive microenvironment plays a major role in the occurrence and development of tumors. Low apolipoprotein A1 (ApoA1) is closely related to tumor development, but the underlying mechanisms are unclear. This study investigated the association between the serum ApoA1 level and immune microenvironment in endometrial, ovarian, and lung cancers. The serum ApoA1 level was decreased significantly in patients with endometrial and ovarian cancers compared with healthy controls. In endometrial cancer tissues, the low serum ApoA1 group showed increased CD163+ macrophages and decreased CD8+ T cell infiltration compared with the normal serum ApoA1 group. Compromised tumor-infiltrating CD8+ T cell functions and decreased CD8+ T cell infiltration were also found in tumor-bearing ApoA1-knockout mice. CD8+ T cell depletion experiments confirmed that ApoA1 exerted its antitumor activity in a CD8+ T cell-dependent manner. In vitro experiments showed that ApoA1 mimetic peptide L-4F directly potentiated the antitumor activity of CD8+ T cells via the HIF-1α-mediated glycolysis pathway. Mechanistically, ApoA1 suppressed the ubiquitin-mediated degradation pathway of HIF-1α protein by downregulating HIF-1α subunit α inhibitor, which maintained the stability of HIF-1α protein and HIF-1α signal activation. Tumor-bearing ApoA1 transgenic mice showed an increased response to anti-PD-1 therapy with inhibited tumor growth and increased tumor necrosis. Here, the data demonstrate the critical roles of ApoA1 in enhancing CD8+ T cell immune functions via HIF-1α-mediated glycolysis, which supports clinical investigation of combined ApoA1 supplementation and anti-PD-1 therapy for tumors.
Project description:High-grade serous ovarian cancer (HG-SOC), characterized by very frequent mutations in TP53 gene, is a highly lethal cancer and is refractory to therapeutic strategies. In HG-SOC, the reciprocal signal exchange between tumor cells and various types of stromal elements from the tumor microenvironment (TME) shapes the malignant phenotype and limits drug efficacy, suggesting that blunting the HG-SOC/TME interplay may improve the anti-tumor therapy response rate. Here, we unveil how the endothelin-1 (ET-1)/ET-1 receptors (ET-1R) signaling, instructing the mutual inter-regulation between HG-SOC cells, endothelial cells (EC) and activated fibroblasts, regulates malignant progression and PARP inhibitor (PARPi) response. Mechanistically, ET-1 axis, mimicking hypoxia, enhances the mutant p53 (mutp53)/YAP/hypoxia inducible factor-1α (HIF-1α) transcriptional cooperation, that culminates with the release of diffusible mediators, as ET-1 and VEGF, that charting a bilateral HG-SOC/stroma signaling route, regulate the acquisition of pro-metastatic traits and PARPi response. Concurrently, our study establishes that ET-1 signaling its instrumental for the activation of p53/YAP/HIF-1α transcriptional machinery within the EC and the activated fibroblasts, shaping their behaviour and secretome. The dual ET-1R antagonist macitentan, dismantling the ET-1R-mediated mutp53/YAP/HIF-1α network, interferes with the ET-1-guided tumor/stroma communication. In vivo macitentan, sensitizing HG-SOC patient-derived xenografts (PDX) to the PARPi, Olaparib, reduces their metastatic potential. Clinically relevant, ETAR/YAP/HIF-1α gene signature correlates with a dismal prognosis in HG-SOC patients. Our findings recognize in the networking between ET-1R and YAP/mutp53/HIF-1α a tumor/TME shared escaping strategy from DNA damaging agents and support the use of ET-1R antagonists in combinatorial treatments with PARPi for HG-SOC patients.
Project description:Protein arginine methyltransferase 5 (PRMT5) is a desirable anticancer target due to its extensive involvement in cellular processes associated with tumor initiation and progression. This study describes an oral PRMT5 selective inhibitor, SCR-6920, with potent inhibitory activity against multiple tumor types. Cryo-EM structure shows that SCR-6920 binds to PRMT5:MEP50 in a substrate-competitive mode with high binding affinity. Notably, RNAseq analysis links vascular endothelial growth factor (VEGF) to PRMT5 and further studies show that SCR-6920 downregulates hypoxia-inducible factor-1α (HIF-1α) expression through the ubiquitin-proteasome degradation pathway, thereby reducing downstream VEGF secretion. Further in vivo efficacy study demonstrates a synergistic effect for SCR-6920 combined with bevacizumab against ovarian cancer. Additionally, SCR-6920 improves the efficacy of clinical first-line ovarian cancer therapies (paclitaxel, docetaxel, doxorubicin, and olaparib). SCR-6920 has progressed into phase 1 clinical trials for solid tumors, and this study paves the way for its future clinical combination exploration in ovarian cancer.
Project description:<p>Acute kidney injury (AKI) is a known risk factor for the development of chronic kidney disease (CKD), with no satisfactory strategy to prevent the progression of AKI to CKD. Damage to the renal vascular system and subsequent hypoxia are common contributors to both AKI and CKD. Hypoxia inducible factor (HIF) is reported to protect the kidney from acute ischemic damage and a novel HIF stabilizer, FG4592 (Roxadustat), has become available in the clinic as an anti-anemia drug. However, the role of FG4592 in the AKI-to-CKD transition remains elusive. In the present study, we investigated the role of FG4592 in the AKI-to-CKD transition induced by unilateral kidney ischemia-reperfusion (UIR). The results showed that FG4592, given to mice 3 days after UIR, markedly alleviated kidney fibrosis and enhanced renal vascular regeneration, possibly via activating the HIF-1α/vascular endothelial growth factor A (VEGFA)/VEGF receptor 1 (VEGFR1) signaling pathway and driving the expression of the endogenous antioxidant superoxide dismutase 2 (SOD2). In accordance with the improved renal vascular regeneration and redox balance, the metabolic disorders of the UIR mice kidneys were also attenuated by treatment with FG4592. However, the inflammatory response in the UIR kidneys was not affected significantly by FG-4592. Importantly, in the kidneys of CKD patients, we also observed enhanced HIF-1α expression which was positively correlated with the renal levels of VEGFA and SOD2. Together, these findings demonstrated the therapeutic effect of the anti-anemia drug FG-4592 in preventing the AKI-to-CKD transition related to ischemia and the redox imbalance.</p><p><br></p><p>Linked study:</p><p><strong>UPLC-MS assay</strong> of mice kidney tissues sacrificed at <strong>day 21 </strong>after UIR is reported in <a href='https://www.ebi.ac.uk/metabolights/MTBLS3003' rel='noopener noreferrer' target='_blank'>MTBLS3003</a></p>
Project description:<p>Acute kidney injury (AKI) is a known risk factor for the development of chronic kidney disease (CKD), with no satisfactory strategy to prevent the progression of AKI to CKD. Damage to the renal vascular system and subsequent hypoxia are common contributors to both AKI and CKD. Hypoxia inducible factor (HIF) is reported to protect the kidney from acute ischemic damage and a novel HIF stabilizer, FG4592 (Roxadustat), has become available in the clinic as an anti-anemia drug. However, the role of FG4592 in the AKI-to-CKD transition remains elusive. In the present study, we investigated the role of FG4592 in the AKI-to-CKD transition induced by unilateral kidney ischemia-reperfusion (UIR). The results showed that FG4592, given to mice 3 days after UIR, markedly alleviated kidney fibrosis and enhanced renal vascular regeneration, possibly via activating the HIF-1α/vascular endothelial growth factor A (VEGFA)/VEGF receptor 1 (VEGFR1) signaling pathway and driving the expression of the endogenous antioxidant superoxide dismutase 2 (SOD2). In accordance with the improved renal vascular regeneration and redox balance, the metabolic disorders of the UIR mice kidneys were also attenuated by treatment with FG4592. However, the inflammatory response in the UIR kidneys was not affected significantly by FG-4592. Importantly, in the kidneys of CKD patients, we also observed enhanced HIF-1α expression which was positively correlated with the renal levels of VEGFA and SOD2. Together, these findings demonstrated the therapeutic effect of the anti-anemia drug FG-4592 in preventing the AKI-to-CKD transition related to ischemia and the redox imbalance.</p><p><br></p><p>Linked study:</p><p><strong>UPLC-MS assay</strong> of mice kidney tissue sacrificed at<strong> day 10 </strong>after UIR is reported in <a href='https://www.ebi.ac.uk/metabolights/MTBLS3056' rel='noopener noreferrer' target='_blank'>MTBLS3056</a></p>
Project description:Congenital vascular malformations, affecting 0.5% of the population, frequently occur in the head and neck, complicating treatment due to their vital functions. Our previous research identified distinct developmental origins for blood and lymphatic vessels in these regions in both mouse and human embryos. In this study, we expressed Pik3caH1047R in the cardiopharyngeal mesoderm (CPM) to investigate the pathogenesis of these malformations. Mice expressing Pik3caH1047R in the CPM developed abnormal vasculature restricted to the head and neck. Single-cell RNA sequencing revealed that Pik3caH1047R promotes Vegf-a expression in endothelial cells via Hif-driven hypoxia signaling. Human samples corroborated these findings, showing elevated HIF-1α and VEGF-A in malformed vessels. Notably, treatment with Hif-1α and Vegf-a inhibitors significantly reduced abnormal vasculature in the mouse model. Our findings highlight the role of developmental origins and hypoxia-driven mechanisms in vascular malformations, providing a basis for developing targeted therapies for these refractory conditions.