Functional proteogenomics reveals biomarkers and therapeutic targets in lymphomas

Identification of biomarkers and therapeutic targets is a critical goal of precision medicine. N-glycoproteins are a particularly attractive class of proteins that constitute potential cancer biomarkers and therapeutic targets for small molecules, antibodies, and cellular therapies. Using mass spectrometry (MS), we generated a compendium of 1,091 N-glycoproteins (from 40 human primary lymphomas and cell lines). Hierarchical clustering revealed distinct subtype signatures that included several subtype-specific biomarkers. Orthogonal immunological studies in 671 primary lymphoma tissue biopsies and 32 lymphoma-derived cell lines corroborated MS data. In anaplastic lymphoma kinase-positive (ALK+) anaplastic large cell lymphoma (ALCL), integration of N-glycoproteomics and transcriptome sequencing revealed an ALK-regulated cytokine/receptor signaling network, including vulnerabilities corroborated by a genome-wide clustered regularly interspaced short palindromic screen. Functional targeting of IL-31 receptor β, an ALCL-enriched and ALK-regulated N-glycoprotein in this network, abrogated ALK+ALCL growth in vitro and in vivo. Our results highlight the utility of functional proteogenomic approaches for discovery of cancer biomarkers and therapeutic targets.

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A Novel JAK1 Mutant Breast Implant-Associated Anaplastic Large Cell Lymphoma Patient-Derived Xenograft Fostering Pre-Clinical Discoveries

Cancers ◽

10.3390/cancers12061603 ◽

2020 ◽

Vol 12 (6) ◽

pp. 1603 ◽

Cited By ~ 1

Author(s):

Danilo Fiore ◽

Luca Vincenzo Cappelli ◽

Paul Zumbo ◽

Jude M. Phillips ◽

Zhaoqi Liu ◽

...

Keyword(s):

Cell Lymphoma ◽

Breast Implant ◽

Large Cell ◽

Tumor Xenograft ◽

Sensitivity Threshold ◽

Primary Lymphoma ◽

Molecular Features ◽

Primary Sample

Breast implant-associated lymphoma (BIA-ALCL) has recently been recognized as an independent peripheral T-cell lymphoma (PTCL) entity. In this study, we generated the first BIA-ALCL patient-derived tumor xenograft (PDTX) model (IL89) and a matching continuous cell line (IL89_CL#3488) to discover potential vulnerabilities and druggable targets. We characterized IL89 and IL89_CL#3488, both phenotypically and genotypically, and demonstrated that they closely resemble the matching human primary lymphoma. The tumor content underwent significant enrichment along passages, as confirmed by the increased variant allele frequency (VAF) of mutations. Known aberrations (JAK1 and KMT2C) were identified, together with novel hits, including PDGFB, PDGFRA, and SETBP1. A deep sequencing approach allowed the detection of mutations below the Whole Exome Sequencing (WES) sensitivity threshold, including JAK1G1097D, in the primary sample. RNA sequencing confirmed the expression of a signature of differentially expressed genes in BIA-ALCL. Next, we tested IL89’s sensitivity to the JAK inhibitor ruxolitinib and observed a potent anti-tumor effect, both in vitro and in vivo. We also implemented a high-throughput drug screening approach to identify compounds associated with increased responses in the presence of ruxolitinib. In conclusion, these new IL89 BIA-ALCL models closely recapitulate the primary correspondent lymphoma and represent an informative platform for dissecting the molecular features of BIA-ALCL and performing pre-clinical drug discovery studies, fostering the development of new precision medicine approaches.

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Ablation of oncogenic ALK is a viable therapeutic approach for anaplastic large-cell lymphomas

Blood ◽

10.1182/blood-2005-05-2125 ◽

2006 ◽

Vol 107 (2) ◽

pp. 689-697 ◽

Cited By ~ 80

Author(s):

Roberto Piva ◽

Roberto Chiarle ◽

Andrea D. Manazza ◽

Riccardo Taulli ◽

William Simmons ◽

...

Keyword(s):

Catalytic Domain ◽

Cellular Transformation ◽

Large Cell ◽

Tumor Growth Inhibition ◽

Chromosome Translocations ◽

Anaplastic Lymphoma ◽

Lymphoid Neoplasia ◽

Downstream Effectors

Abstract Anaplastic large-cell lymphomas (ALCLs) carry chromosome translocations in which the anaplastic lymphoma kinase (ALK) gene is fused to several partners, most frequently, the NPM1 gene. We have demonstrated that the constitutive activation of ALK fusion proteins results in cellular transformation and lymphoid neoplasia. Herein, we specifically down-regulated ALK protein expression by using small hairpin RNA (shRNA) targeting a sequence coding for the catalytic domain of ALK. The ablation of ALK leads to the down-modulation of known ALK downstream effectors, cell growth arrest, and reversion of the transformed phenotype of ALK+ mouse embryonic fibroblasts in vitro and in vivo. In human ALCL cells lentiviral-mediated ALK knock-down leads to G1 cell-cycle arrest and apoptosis in vitro and tumor growth inhibition and regression in vivo. Using a specific approach we have demonstrated that the survival and growth of ALK+ ALCLs are strictly dependent on ALK activation and signaling. Therefore, ALK is a viable target for therapeutic intervention and its inactivation might represent a pivotal approach for the treatment of ALK lymphomas and other ALK-dependent human tumors.

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Preclinical Activity of Brentuximab Vedotin (SGN-35) in Primary Effusion Lymphoma (PEL),

Blood ◽

10.1182/blood.v118.21.3728.3728 ◽

2011 ◽

Vol 118 (21) ◽

pp. 3728-3728 ◽

Cited By ~ 1

Author(s):

Shruti Bhatt ◽

Brittany Ashlock ◽

Yaso Natkunam ◽

Juan Carlos Ramos ◽

Enrique Mesri ◽

...

Keyword(s):

Flow Cytometry ◽

Cell Lines ◽

Conflicts Of Interest ◽

Primary Effusion Lymphoma ◽

Large Cell ◽

Brentuximab Vedotin ◽

Antibody Drug Conjugate ◽

Human Herpes Virus 8

Abstract Abstract 3728 Primary effusion lymphoma (PEL) is a distinct and aggressive subtype of non-Hodgkin lymphoma (NHL) commonly presenting with pleural, peritoneal, or pericardial malignant effusions usually without a contiguous tumor mass. PEL is most commonly diagnosed in HIV-positive patients, accounting for 4% of all NHLs in this population, yet may also develop in immunosuppressed HIV-negative individuals. While Human Herpes Virus 8 (HHV8 or Kaposi's sarcoma-associated herpesvirus) is directly implicated in the oncogenesis of this lymphoma, most PEL cases are also associated with Epstein-Barr virus and the combination of the two may facilitate transformation. The tumor cells exhibit plasmablastic features and express CD45, CD38, CD138, HHV8 and CD30. PEL is an aggressive tumor characterized by a short median survival of only 6 months with current therapeutic approaches underscoring the urgent need for development of new therapeutics. Brentuximab vedotin (SGN-35) is an antibody-drug conjugate (ADC) comprised of an anti-CD30 monoclonal antibody cAC10 conjugated by a protease-cleavable dipeptide linker to a potent cell killing agent monomethyl auristatin E (MMAE). Following binding to CD30, brentuximab vedotin is rapidly internalized and is transported to lysosomes, where the peptide linker is selectively cleaved allowing binding of the released MMAE to tubulin and leading to cell cycle arrest and apoptosis. Brentuximab vedotin was recently reported to have promising antitumor activity in CD30 expressing tumors, such as Hodgkin and Anaplastic large cell lymphomas. Since PEL tumors are reported to express CD30, we have hypothesized that brentuximab vedotin might be effective in the treatment of this NHL subtype. Initially, we have confirmed by flow cytometry the expression of CD30 on PEL cell lines (UM-PEL 1, UM-PEL 3, BC-1 and BC-3), and by review of immunohistochemistry and flow cytometry results in patients with previous diagnosis of PEL at our institution. To examine in vitro potency of brentuximab vedotin, UM-PEL 1, UM-PEL 3, BC-1 and BC-3 PEL cell lines were treated with brentuximab vedotin at concentration ranging from 0–100 micrograms/ml. Staining with YO-PRO and Propidium Iodide (PI) demonstrated dose dependent cell apoptosis and death in all the cell lines at 72 hours post treatment. In contrast, control IgG conjugated with MMAE failed to induce apoptosis and cell death of PEL cell lines confirming specific brentuximab vedotin cytotoxicity. Furthermore, brentuximab vedotin decreased proliferation of PEL cells at 48 hours leading to a complete proliferation arrest at 72 hours, as measured by MTS assay. These effects were absent after equivalent doses of control IgG conjugated drug treatment. Supportive to this, labeling of cells with PI to detect active DNA content by flow cytometry showed that bretuximab vedotin induced growth arrest in G2/M phase. To further establish the anti-tumor potential of brentuximab vedotin in vivo, we used the direct xenograft UM-PEL 1 model, established in our laboratory (Sarosiek, PNAS 2010), which mimics human PEL tumors. UM-PEL 1 bearing mice were injected intraperitoneally 3 times a week with brentuximab vedotin or control IgG conjugated MMAE for 4 weeks. Brentuximab vedotin treatment markedly prolonged overall survival of UM-PEL-1 bearing mice compared to controls (p Disclosures: No relevant conflicts of interest to declare.

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Identifying Mechanisms of Glucocorticoid Resistance in Relapsed Pediatric T-ALL

Blood ◽

10.1182/blood.v128.22.2769.2769 ◽

2016 ◽

Vol 128 (22) ◽

pp. 2769-2769 ◽

Cited By ~ 1

Author(s):

Justine E. Roderick ◽

Kayleigh M Gallagher ◽

Katherine M Tang ◽

Olivia Kugler-Umana ◽

Lihua J Zhu ◽

...

Keyword(s):

Cell Lines ◽

Resistance Genes ◽

Glucocorticoid Resistance ◽

Human Leukemia ◽

Suppressor Genes ◽

A Genome ◽

Dexamethasone Resistance ◽

Pediatric All

Abstract While great strides have been made in the improvement of outcome for newly diagnosed pediatric acute lymphoblastic leukemia (ALL) patients, prognosis for relapsed leukemia patients remains poor. The synthetic glucocorticoid (GC) dexamethasone is part of the standard treatment for pediatric ALL and patient response to glucocorticoid treatment has proved to be a reliable prognostic indicator. Identifying the biological pathways responsible for glucocorticoid resistance may reveal novel therapeutic targets to prevent and treat relapsed ALL. Although genomic analyses of relapsed patients and matched diagnosis-relapse patient pairs have begun to define the genomic landscape of relapsed disease, discerning "driver from passenger" genetic lesions remains challenging. To identify glucocorticoid resistance genes in an unbiased, high-throughput manner, we conducted a genome wide, survival based, shRNA screen in dexamethasone sensitive murine T-ALL cells. Our preliminary data identify several hundred genes capable of mediating GC resistance, including several known GC resistance genes Nr3c1, Rcan1, Btg1 and Mllt10, thereby validating our experimental approach. Candidate genes identified in the screen including EP300 (p300), GATA3 and IKZF1 are known leukemia suppressors in pediatric ALL and the EP300 paralog CREBBP and IKAROS have been linked to GC resistance, indicating that suppressor genes involved in human leukemia and GC resistance are identified in our mouse screen. Consistently, we found the expression of several screen hits significantly decreased and/or mutated in relapse patient samples. Novel dexamethasone resistance genes identified in the screen interfere with GC-induced transcription (Stat3, Ikzf1), promote pluripotency (Esrrb, Sox2) or stimulate cAMP signaling (Adcy3, Gnas, Creb1). Silencing of these genes in multiple mouse T-ALL cell lines has no detectable effects on leukemic growth/survival in vitro, but confers resistance to dexamethasone treatment in vitro and in vivo. Moreover, we show that silencing of some candidate dexamethasone resistance genes accelerates leukemogenesis in vivo, demonstrating that leukemia suppressor genes were identified. Effect(s) of silencing or inhibiting these novel dexamethasone resistance genes/pathways in human T-ALL cell lines, primary patient samples and xenografts will be discussed. We predict that targeting these dexamethasone resistance pathways may re-sensitize relapse pediatric T-ALL cells to dexamethasone and/or contribute to more effective patient stratification to prevent relapse and induction failure. Disclosures No relevant conflicts of interest to declare.

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Synergistic Drug Combinations Prevent Resistance in ALK+ Anaplastic Large Cell Lymphoma

Cancers ◽

10.3390/cancers13174422 ◽

2021 ◽

Vol 13 (17) ◽

pp. 4422

Author(s):

Giulia Arosio ◽

Geeta G. Sharma ◽

Matteo Villa ◽

Mario Mauri ◽

Ilaria Crespiatico ◽

...

Keyword(s):

Anaplastic Large Cell Lymphoma ◽

Cell Lymphoma ◽

Large Cell ◽

Drug Combinations ◽

Tumor Growth Inhibition ◽

Anaplastic Lymphoma ◽

Alk Inhibitor ◽

Large Cell Lymphoma

Anaplastic lymphoma kinase-positive (ALK+) anaplastic large-cell lymphoma (ALCL) is a subtype of non-Hodgkin lymphoma characterized by expression of the oncogenic NPM/ALK fusion protein. When resistant or relapsed to front-line chemotherapy, ALK+ ALCL prognosis is very poor. In these patients, the ALK inhibitor crizotinib achieves high response rates, however 30–40% of them develop further resistance to crizotinib monotherapy, indicating that new therapeutic approaches are needed in this population. We here investigated the efficacy of upfront rational drug combinations to prevent the rise of resistant ALCL, in vitro and in vivo. Different combinations of crizotinib with CHOP chemotherapy, decitabine and trametinib, or with second-generation ALK inhibitors, were investigated. We found that in most cases combined treatments completely suppressed the emergence of resistant cells and were more effective than single drugs in the long-term control of lymphoma cells expansion, by inducing deeper inhibition of oncogenic signaling and higher rates of apoptosis. Combinations showed strong synergism in different ALK-dependent cell lines and better tumor growth inhibition in mice. We propose that drug combinations that include an ALK inhibitor should be considered for first-line treatments in ALK+ ALCL.

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Identification of putative markers of triclabendazole resistance by a genome-wide analysis of genetically recombinant Fasciola hepatica

Parasitology ◽

10.1017/s0031182013000528 ◽

2013 ◽

Vol 140 (12) ◽

pp. 1523-1533 ◽

Cited By ~ 31

Author(s):

J. HODGKINSON ◽

K. CWIKLINSKI ◽

N. J. BEESLEY ◽

S. PATERSON ◽

D. J. L. WILLIAMS

Keyword(s):

Genetic Resources ◽

Fasciola Hepatica ◽

Genome Wide Analysis ◽

Extensive Analysis ◽

Genome Wide ◽

A Genome ◽

Genetic Mechanisms ◽

Triclabendazole Resistance

SUMMARYDespite years of investigation into triclabendazole (TCBZ) resistance in Fasciola hepatica, the genetic mechanisms responsible remain unknown. Extensive analysis of multiple triclabendazole-susceptible and -resistant isolates using a combination of experimental in vivo and in vitro approaches has been carried out, yet few, if any, genes have been demonstrated experimentally to be associated with resistance phenotypes in the field. In this review we summarize the current understanding of TCBZ resistance from the approaches employed to date. We report the current genomic and genetic resources for F. hepatica that are available to facilitate novel functional genomics and genetic experiments for this parasite in the future. Finally, we describe our own non-biased approach to mapping the major genetic loci involved in conferring TCBZ resistance in F. hepatica.

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A genome-wide CRISPR screen identifies the glycosylation enzyme DPM1 as a modifier of DPAGT1 deficiency and ER stress

10.1101/2021.12.03.471178 ◽

2021 ◽

Author(s):

Hans M. Dalton ◽

Raghuvir Viswanatha ◽

Ricky Brathwaite ◽

Jae Sophia Zuno ◽

Stephanie E. Mohr ◽

...

Keyword(s):

Er Stress ◽

Therapeutic Targets ◽

Therapeutic Benefit ◽

Loss Of Function ◽

Gene Encoding ◽

Fructose Metabolism ◽

Genome Wide ◽

A Genome ◽

Crispr Screen

AbstractPartial loss-of-function mutations in glycosylation pathways underlie a set of rare diseases called Congenital Disorders of Glycosylation (CDGs). In particular, DPAGT1-CDG is caused by mutations in the gene encoding the first step in N-glycosylation, DPAGT1, and this disorder currently lacks effective therapies. To identify potential therapeutic targets for DPAGT1-CDG, we performed CRISPR knockout screens in Drosophila cells for genes associated with better survival and glycoprotein levels under DPAGT1 inhibition. We identified hundreds of candidate genes that may be of therapeutic benefit. Intriguingly, inhibition of the mannosyltransferase Dpm1, or its downstream glycosylation pathways, could rescue two in vivo models of DPAGT1 inhibition and ER stress, even though impairment of these pathways alone usually cause CDGs. While both in vivo models ostensibly cause ER stress (through DPAGT1 inhibition or a misfolded protein), we found a novel difference in fructose metabolism that may indicate glycolysis as a modulator of DPAGT1-CDG. Our results provide new therapeutic targets for DPAGT1-CDG, include the unique finding of Dpm1-related pathways rescuing DPAGT1 inhibition, and reveal a novel interaction between fructose metabolism and ER stress.

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GSK1838705a, an IGF-1R/ALK Inhibitor, Overcomes Resistance to Crizotinib in ALK-Positive ALCL

Blood ◽

10.1182/blood-2019-130063 ◽

2019 ◽

Vol 134 (Supplement_1) ◽

pp. 4069-4069

Author(s):

Wenyu Shi ◽

Jian-Yong Li

Keyword(s):

Cell Line ◽

Cell Lines ◽

Large Cell ◽

Resistant Cell ◽

Resistant Cell Line ◽

Expression Level ◽

Downstream Signaling ◽

Single Drug

Anaplastic large cell lymphoma (ALCL) is a type of CD30-expressing non-Hodgkin's lymphoma (NHL), which accounts for 2% to 3% of adult non-Hodgkin's lymphoma,accounting for 15% to 30% of children with large cell lymphoma. Anaplastic lymphoma kinase (ALK) positive ALCL is highly invasive, and currently it is generally based on CHOP combined with chemotherapy. The proportion of patients with complete relief of symptoms is as high as 90%, but the proportion of recurrence is also as high as 40%. Crizotinib is the first generation of ALK inhibitors that have been approved for the treatment of ALK+ ALCL. Unfortunately, most patients treated with crizotinib relapse after a significant initial response. The median progression-free survival of clinical trials was 10.5 months. Various mutations in the ALK kinase domain and amplification of the ALK gene copy number, activation of the alternative pathway, and tumor heterogeneity are major causes of crizotinib resistance. Studies have shown that IGF-1R interacts with NPM-ALK to promote ALK+ALCL transformation, proliferation and migration. GSK is a small molecule kinase inhibitor that inhibits both IGF-IR and ALK. Therefore, GSK with simultaneous inhibition of the bidirectional potential of IGF-IR and ALK has a promising prospect in the targeted therapy of NPM-ALK+ALCL. This study explored the inhibitory effects of GSK on NPM-ALK+ALCL and crizotinib-resistant NPM-ALK+ALCL by in vivo and in vitro experiments. In vitro experiments: The sensitivity of ALCL cell line to GSK1838705a was detected by CCK8 and flow cytometry. The expression of phosphorylation of IGF-1R and NPM-ALK signaling pathway in Karpas299 and SR786 cell lines stimulated by GSK was detected by WB method. In order to study the crizotinib resistance mutation, we established ALK+ALCL crizotinib-resistant cell lines Karpas299-R and SR786-R, and identified the resistance of Karpas299-R and SR786-R cell lines by CCK8 and flow cytometry. The drug-resistant and non-resistant strains were stimulated with gradient concentrations of crizotinib and gradient GSK, and the IC50 of the two were compared by CCK8. The WB method was used to compare the phosphorylation levels of downstream signaling pathways in drug-resistant and non-resistant strains. In vivo experiment: The ALK+ALCL and resistant-ALK+ALCL mouse model was established, and three groups of mice treated with control, GSK single drug 30 mg/kg, GSK single drug 60 mg/kg, were established. The tumor volume and body weight of the four groups were compared. Immunohistochemistry was used to compare the expression levels of key signaling molecules and apoptotic proteins in each group. SPSS statistical software draws survival curves. As the concentration of GSK gradually increases, the survival rate of ALCL cells gradually decreases. The expression of pIGF-1R, pNPM-ALK, pSTAT3, pAKT, casepase3 and other molecules decreased in the downstream signaling pathway, and the expression level of cleaved-casepase3 increased.In the crizotinib-resistant cell line, with the increase of the concentration of GSK, the apoptosis rate of the cells increased and the phosphorylation level of the downstream molecules gradually decreased. Tumor volume of three groups of mouse models: control>GSK single drug 30 mg/kg>GSK single drug 60 mg/kg. Immunohistochemistry results showed that the expression level of key signaling molecules in GSK-treated CHOP-treated mice decreased, and the expression level of apoptotic proteins increased. In this research, we explored the effects of GSK1838705A on proliferation, apoptosis, and clonogenesis of ALCL cell lines. Subsequently, we established a crizotinib-resistant cell line and noticed that GSK1838705A can effectively reduce the viability of resistant ALCL cells and significantly restrain the transmission of downstream survival signaling pathways induced by IGF1R/IR phosphorylation. Besides, we discovered that GSK1838705A inhibited the development of both crizotinib-sensitive and crizotinib-resistant ALCL tumors in the ALCL mouse model established by subcutaneous tumorigenesis. Based on the results of previous clinical trials, we put forward to use GSK1838705A as an alternative treatment strategy to overcome crizotinib-resistant ALCL. Disclosures No relevant conflicts of interest to declare.

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Super-enhancer-based identification of a BATF3/IL-2R−module reveals vulnerabilities in anaplastic large cell lymphoma

Nature Communications ◽

10.1038/s41467-021-25379-9 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Huan-Chang Liang ◽

Mariantonia Costanza ◽

Nicole Prutsch ◽

Mark W. Zimmerman ◽

Elisabeth Gurnhofer ◽

...

Keyword(s):

Anaplastic Large Cell Lymphoma ◽

Cell Lymphoma ◽

Breast Implant ◽

Large Cell ◽

Antibody Drug Conjugate ◽

Anaplastic Lymphoma ◽

Super Enhancer ◽

Large Cell Lymphoma

AbstractAnaplastic large cell lymphoma (ALCL), an aggressive CD30-positive T-cell lymphoma, comprises systemic anaplastic lymphoma kinase (ALK)-positive, and ALK-negative, primary cutaneous and breast implant-associated ALCL. Prognosis of some ALCL subgroups is still unsatisfactory, and already in second line effective treatment options are lacking. To identify genes defining ALCL cell state and dependencies, we here characterize super-enhancer regions by genome-wide H3K27ac ChIP-seq. In addition to known ALCL key regulators, the AP-1-member BATF3 and IL-2 receptor (IL2R)-components are among the top hits. Specific and high-level IL2R expression in ALCL correlates with BATF3 expression. Confirming a regulatory link, IL-2R-expression decreases following BATF3 knockout, and BATF3 is recruited to IL2R regulatory regions. Functionally, IL-2, IL-15 and Neo-2/15, a hyper-stable IL-2/IL-15 mimic, accelerate ALCL growth and activate STAT1, STAT5 and ERK1/2. In line, strong IL-2Rα-expression in ALCL patients is linked to more aggressive clinical presentation. Finally, an IL-2Rα-targeting antibody-drug conjugate efficiently kills ALCL cells in vitro and in vivo. Our results highlight the importance of the BATF3/IL-2R-module for ALCL biology and identify IL-2Rα-targeting as a promising treatment strategy for ALCL.

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Abstract 360: Loss of Endothelial CXCR7 Exacerbates Wire-injury Induced Neointimal Formation

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/atvb.36.suppl_1.360 ◽

2016 ◽

Vol 36 (suppl_1) ◽

Author(s):

Huifeng Hao ◽

Sheng Hu ◽

Dawei Bu ◽

Xiaogang Sun ◽

Miao Wang

Keyword(s):

Vascular Remodeling ◽

Tamoxifen Treatment ◽

Neointimal Formation ◽

Genome Wide ◽

Endothelial Repair ◽

A Genome ◽

Artery Disease

CXCR7 is a non-classical chemokine receptor for CXCL12, whose gene represents a genome-wide association locus for coronary artery disease. Global deletion of CXCR7 increased experimentally induced neointimal formation and atherosclerosis in hyperlipidemic mice, with evidence that CXCR7 modified cholesterol uptake to adipose tissue. We found that CXCR7 was expressed in endothelial cells of mouse neointima and human aortic lesions. To examine a role of endothelial CXCR7 in vascular remodeling, endothelial CXCR7 inducible knockout mice were studied for their vascular response to wire injury in femoral arteries. Tamoxifen treatment of mice harboring floxed CXCR7 and Cdh5 -promoter driven CreERT2 , essentially abolished endothelial CXCR7 expression in vitro and in vivo. Postnatal deletion of endothelial CXCR7 exacerbated neointimal formation on normalipidemic background, four weeks after injury. Mechanistically, this was attributable to attenuated endothelial repair following endothelial injury. Collectively, endothelial CXCR7 is a key regulator of vascular remodeling, independent of lipid traits.

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