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1.
Mol Pharm ; 20(9): 4559-4573, 2023 09 04.
Article in English | MEDLINE | ID: mdl-37555521

ABSTRACT

The enzyme PACE4 has been validated as a promising therapeutic target to expand the range of prostate cancer (PCa) treatments. In recent years, we have developed a potent peptidomimetic inhibitor, namely, compound C23 (Ac-(DLeu)LLLRVK-4-amidinobenzylamide). Like many peptides, C23 suffers from an unfavorable drug-like profile which, despite our efforts, has not yet benefited from the usual SAR studies. Hence, we turned our attention toward a novel formulation strategy, i.e., the use of cyclodextrins (CDs). CDs can benefit compounds through the formation of "host-guest" complexes, shielding the guest from degradation and enhancing biological survival. In this study, a series of ßCD-C23 complexes have been generated and their properties evaluated, including potency toward the enzyme in vitro, a cell-based proliferation assay, and stability in plasma. As a result, a new ßCD-formulated lead compound has been identified, which, in addition to being more soluble and more potent, also showed an improved stability profile.


Subject(s)
Cyclodextrins , beta-Cyclodextrins , Male , Humans , Peptides/pharmacology , beta-Cyclodextrins/pharmacology , Cyclodextrins/pharmacology , Cyclodextrins/chemistry
2.
Dev Dyn ; 251(11): 1880-1896, 2022 11.
Article in English | MEDLINE | ID: mdl-35809036

ABSTRACT

BACKGROUND: Limb buds develop as bilateral outgrowths of the lateral plate mesoderm and are patterned along three axes. Current models of proximal to distal patterning of early amniote limb buds suggest that two signals, a distal organizing signal from the apical epithelial ridge (AER, Fgfs) and an opposing proximal (retinoic acid [RA]) act early on pattern this axis. RESULTS: Transcriptional analysis of stage 51 Xenopus laevis hindlimb buds sectioned along the proximal-distal axis showed that the distal region is distinct from the rest of the limb. Expression of capn8.3, a novel calpain, was located in cells immediately flanking the AER. The Wnt antagonist Dkk1 was AER-specific in Xenopus limbs. Two transcription factors, sall1 and zic5, were expressed in distal mesenchyme. Zic5 has no described association with limb development. We also describe expression of two proximal genes, gata5 and tnn, not previously associated with limb development. Differentially expressed genes were associated with Fgf, Wnt, and RA signaling as well as differential cell adhesion and proliferation. CONCLUSIONS: We identify new candidate genes for early proximodistal limb patterning. Our analysis of RA-regulated genes supports a role for transient RA gradients in early limb bud in proximal-to-distal patterning in this anamniote model organism.


Subject(s)
Gene Expression Regulation, Developmental , Limb Buds , Animals , Limb Buds/metabolism , Xenopus laevis/genetics , Xenopus laevis/metabolism , Mesoderm/metabolism , Fibroblast Growth Factors/genetics , Fibroblast Growth Factors/metabolism , Tretinoin/metabolism , Extremities , Gene Expression , Ectoderm/metabolism , DNA-Binding Proteins/genetics , Nerve Tissue Proteins/genetics , Xenopus Proteins/genetics , Xenopus Proteins/metabolism
3.
Hum Mol Genet ; 29(4): 554-565, 2020 03 13.
Article in English | MEDLINE | ID: mdl-31691800

ABSTRACT

Abdominal aortic aneurysm (AAA) is a major cause of sudden death in the elderly. While AAA has some overlapping genetic and environmental risk factors with atherosclerosis, there are substantial differences, and AAA-specific medication is lacking. A recent meta-analysis of genome-wide association studies has identified four novel single-nucleotide polymorphisms (SNPs) specifically associated with AAA. Here, we investigated the gene regulatory function for one of four non-coding SNPs associated with AAA, rs2836411, which is located in an intron of the ERG gene. Rs2836411 resides within a >70 kb super-enhancer that has high levels of H3K27ac and H3K4me1 in vascular endothelial and haematopoietic cell types. Enhancer luciferase assays in cell lines showed that the risk allele significantly alters enhancer activity. The risk allele also correlates with reduced ERG expression in aortic and other vascular tissues. To identify whether rs2836411 directly contacts the promoters of ERG and/or of genes further away, we performed allele-specific circular chromosome conformation capture sequencing. In vascular endothelial cells, which express ERG, the SNP region interacts highly within the super-enhancer, while in vascular smooth muscle cells, which do not express ERG, the interactions are distributed across a wider region that includes neighbouring genes. Furthermore, the risk allele has fewer interactions within the super-enhancer compared to the protective allele. In conclusion, our results indicate that rs2836411 likely affects ERG expression by altering enhancer activity and changing local chromatin interactions. ERG is involved in vascular development, angiogenesis, and inflammation in atherosclerosis; therefore mechanistically, rs2836411 could contribute to AAA by modulating ERG levels.


Subject(s)
Aortic Aneurysm, Abdominal/genetics , Aged , Alleles , Aorta, Abdominal/metabolism , Aortic Aneurysm, Abdominal/metabolism , Case-Control Studies , Endothelial Cells , Gene Expression Regulation/genetics , Genes, Regulator/genetics , Genetic Predisposition to Disease/genetics , Genome-Wide Association Study , Hep G2 Cells , Human Umbilical Vein Endothelial Cells , Humans , Introns/genetics , Male , Myocytes, Smooth Muscle , Phenotype , Polymorphism, Single Nucleotide/genetics , Promoter Regions, Genetic/genetics , Quantitative Trait Loci/genetics , Risk Factors , Transcriptional Regulator ERG/genetics
4.
Am J Perinatol ; 2022 Sep 16.
Article in English | MEDLINE | ID: mdl-35863371

ABSTRACT

OBJECTIVE: Prostaglandins (PGs) use for cervical ripening with small for gestational age (SGA) fetuses is controversial since it remains uncertain if use increases the chance of cesarean delivery (CD). We aimed to assess the association between PG use for cervical ripening and mode of delivery between SGA and appropriate for gestational age (AGA) neonates. STUDY DESIGN: Secondary analysis of the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be (nuMoM2b), a prospective observational cohort study of 10,038 nulliparas. We included women undergoing induction with nonanomalous fetuses in the cephalic presentation. Women with >2 cm cervical dilation or prior uterine scar were excluded. We assessed the association of PG use with CD among women with SGA and AGA neonates. SGA was defined as birth weight <10th percentile for gestational age and sex. Multivariable logistic regression was used to adjust for potential confounders and test for interaction. Secondary outcomes included adverse neonatal outcomes, indication for CD, maternal hemorrhage, and chorioamnionitis. RESULTS: Among 2,353 women eligible, PGs were used in 54.8%, SGA occurred in 15.1%, and 35.0% had CD. The association between PG use and CD differed significantly (interaction p = 0.018) for SGA versus AGA neonates; CD occurred more often in SGA neonates exposed to PGs than not (35 vs. 22%, p = 0.009). PG use was not associated with CD among AGA neonates (36 vs. 36%, p = 0.8). This effect remained significant when adjusting for body mass index, race/ethnicity, and cervical dilation. Among SGA neonates, CD for "nonreassuring fetal status" was similar between PG groups. Among SGA neonates, PG use was not associated with adverse neonatal outcomes or postpartum hemorrhage but had a higher rate of chorioamnionitis (7.0 vs. 2.1%, p = 0.048). CONCLUSION: PG use was associated with a higher rate of CD in SGA but not AGA neonates; however, further studies are needed before PG use is discouraged with SGA neonates. KEY POINTS: · PGs are commonly used for cervical ripening.. · PG use was associated with increased risk of cesarean delivery in SGA neonates.. · PG use was not associated with adverse neonatal outcomes..

5.
J Biol Chem ; 295(7): 2068-2083, 2020 02 14.
Article in English | MEDLINE | ID: mdl-31915245

ABSTRACT

Many secretory proteins are activated by cleavage at specific sites. The proprotein convertases (PCs) form a family of nine secretory subtilisin-like serine proteases, seven of which cleave at specific basic residues within the trans-Golgi network, granules, or at the cell surface/endosomes. The seventh member, PC7, is a type-I transmembrane (TM) protein with a 97-residue-long cytosolic tail (CT). PC7 sheds human transferrin receptor 1 (hTfR1) into soluble shTfR1 in endosomes. To better understand the physiological roles of PC7, here we focused on the relationship between the CT-regulated trafficking of PC7 and its ability to shed hTfR1. Deletion of the TMCT resulted in soluble PC7 and loss of its hTfR1 shedding activity. Extensive CT deletions and mutagenesis analyses helped us zoom in on three residues in the CT, namely Glu-719, Glu-721, and Leu-725, that are part of a novel motif, EXEXXXL725, critical for PC7 activity on hTfR1. NMR studies of two 14-mer peptides mimicking this region of the CT and its Ala variants revealed that the three exposed residues are on the same side of the molecule. This led to the identification of adaptor protein 2 (AP-2) as a protein that recognizes the EXEXXXL725 motif, thus representing a potentially new regulator of PC7 trafficking and cleavage activity. Immunocytochemistry of the subcellular localization of PC7 and its Ala variants of Leu-725 and Glu-719 and Glu-721 revealed that Leu-725 enhances PC7 localization to early endosomes and that, together with Glu-719 and Glu-721, it increases the endosomal activity of PC7 on hTfR1.


Subject(s)
Antigens, CD/genetics , Cytosol/metabolism , Protein Transport/genetics , Receptors, Transferrin/genetics , Subtilisins/genetics , Transcription Factor AP-2/genetics , Amino Acid Motifs/genetics , Amino Acid Sequence/genetics , Antigens, CD/chemistry , Cell Membrane/genetics , Cell Movement/genetics , Cytosol/chemistry , Endosomes/genetics , HEK293 Cells , Humans , Receptors, Transferrin/chemistry , Subtilisins/chemistry , trans-Golgi Network/genetics
6.
J Pharmacol Exp Ther ; 376(2): 213-221, 2021 02.
Article in English | MEDLINE | ID: mdl-33154104

ABSTRACT

Mouse mast cell protease 4 (mMCP-4), the murine functional analog to the human chymase, is a serine protease synthesized and stored in mast cell secretory granules. Our previous studies reported physiologic and pathologic roles for mMCP-4 in the maturation and synthesis of the vasoactive peptide endothelin-1 (ET-1) from its precursor, big ET-1. The aim of this study was to investigate the impact of mast cell degranulation or stabilization on mMCP-4-dependent pressor responses after the administration of big ET-1 or angiotensin I (Ang I). In anesthetized mice, mast cell degranulation induced by compound 48/80 (C48/80) or stabilization by cromolyn enhanced or repressed, respectively, the dose-dependent vasopressor responses to big ET-1 in wild-type (WT) mice but not in mMCP-4 knockout mice in a chymase inhibitor (TY-51469)-sensitive fashion. In addition, mMCP-4-dependent hydrolysis of the fluorogenic substrate Suc-Leu-Leu-Val-Tyr-7-amino-4-methylcoumarin was depleted or enhanced in peritoneal mast cells isolated from mice pretreated with C48/80 or cromolyn, respectively. Furthermore, C48/80 or cromolyn markedly increased or abolished, respectively, ET-1 (1-31) conversion from exogenous big ET-1 in WT mice peritoneal fluid-isolated mast cells, in vitro. Finally, the vasopressor responses to Ang I were unaffected by mast cell activation or stabilization, whereas those induced by the angiotensin-converting enzyme-resistant Ang I analog, [Pro11, D-Ala12] Ang I, were potentiated by C48/80. Altogether, the present study shows that mast cell activation enhances the mMCP-4-dependent vasoactive properties of big ET-1 but not Ang I in the mouse model. SIGNIFICANCE STATEMENT: The current work demonstrates a significant role for mast cell stability in the cardiovascular pharmacology of big endothelin-1 but not angiotensin I in the murine systemic circulation.


Subject(s)
Angiotensin I/pharmacology , Blood Pressure , Cell Degranulation , Endothelin-1/pharmacology , Mast Cells/physiology , Serine Endopeptidases/metabolism , Animals , Cells, Cultured , Chymases/antagonists & inhibitors , Cromolyn Sodium/pharmacology , Enzyme Inhibitors/pharmacology , Male , Mast Cell Stabilizers/pharmacology , Mast Cells/drug effects , Mast Cells/metabolism , Mice , Mice, Inbred C57BL , Peritoneum/cytology , Serine Endopeptidases/genetics , Sulfonamides/pharmacology , Thiophenes/pharmacology
7.
Genet Med ; 23(3): 543-554, 2021 03.
Article in English | MEDLINE | ID: mdl-33149277

ABSTRACT

PURPOSE: A few de novo missense variants in the cytoplasmic FMRP-interacting protein 2 (CYFIP2) gene have recently been described as a novel cause of severe intellectual disability, seizures, and hypotonia in 18 individuals, with p.Arg87 substitutions in the majority. METHODS: We assembled data from 19 newly identified and all 18 previously published individuals with CYFIP2 variants. By structural modeling and investigation of WAVE-regulatory complex (WRC)-mediated actin polymerization in six patient fibroblast lines we assessed the impact of CYFIP2 variants on the WRC. RESULTS: Sixteen of 19 individuals harbor two previously described and 11 novel (likely) disease-associated missense variants. We report p.Asp724 as second mutational hotspot (4/19 cases). Genotype-phenotype correlation confirms a consistently severe phenotype in p.Arg87 patients but a more variable phenotype in p.Asp724 and other substitutions. Three individuals with milder phenotypes carry putative loss-of-function variants, which remain of unclear pathogenicity. Structural modeling predicted missense variants to disturb interactions within the WRC or impair CYFIP2 stability. Consistent with its role in WRC-mediated actin polymerization we substantiate aberrant regulation of the actin cytoskeleton in patient fibroblasts. CONCLUSION: Our study expands the clinical and molecular spectrum of CYFIP2-related neurodevelopmental disorder and provides evidence for aberrant WRC-mediated actin dynamics as contributing cellular pathomechanism.


Subject(s)
Intellectual Disability , Neurodevelopmental Disorders , Actins/genetics , Adaptor Proteins, Signal Transducing/metabolism , Humans , Intellectual Disability/genetics , Neurodevelopmental Disorders/genetics , Seizures
8.
Carcinogenesis ; 41(11): 1507-1517, 2020 11 13.
Article in English | MEDLINE | ID: mdl-32955091

ABSTRACT

Accurate assessment of chemotherapy response provides the means to terminate ineffective treatment, trial alternative drug regimens or schedules and reduce dose to minimize toxicity. Here, we have compared circulating tumor DNA (ctDNA) with carcinoembryonic antigen (CEA) for the cycle by cycle assessment of chemotherapy response in 30 patients with metastatic colorectal cancer. CtDNA (quantified using individualized digital droplet PCR (ddPCR) assays) and CEA levels were determined immediately prior to each chemotherapy cycle over time periods ranging from 42-548 days (average of 10 time points/patient). Twenty-nine/thirty (97%) patients had detectable ctDNA compared with 83% whose tumors were CEA-positive (>5 ng/ml) during the monitoring course. Over the course of treatment, 20 disease progression events were detected by computed tomography; ctDNA predicted significantly more of these events than CEA (16 (80%) versus 6 (30%), respectively; P-value = 0.004). When progression was detected by both ctDNA and CEA, the rise in ctDNA occurred significantly earlier than CEA (P-value = 0.046). Partial responses to chemotherapy were also detected more frequently by ctDNA, although this was not significant (P-value = 0.07). In addition, another 28 colorectal cancer patients who underwent potentially curative surgery and showed no evidence of residual disease were monitored with ctDNA for up to 2 years. Clinical relapse was observed in 6/28 (21%) patients. Four out of 6 of these patients showed a significant increase in ctDNA at or prior to relapse. Overall, ctDNA analyses were able to be performed in a clinically relevant timeline and were a more sensitive and responsive measure of tumor burden than CEA.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Biomarkers, Tumor/genetics , Circulating Tumor DNA/genetics , Colorectal Neoplasms/pathology , DNA, Neoplasm/genetics , Biomarkers, Tumor/analysis , Circulating Tumor DNA/analysis , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/genetics , DNA, Neoplasm/analysis , Follow-Up Studies , Humans , Prognosis , Prospective Studies , Tumor Burden
9.
Arterioscler Thromb Vasc Biol ; 39(10): 1996-2013, 2019 10.
Article in English | MEDLINE | ID: mdl-31553664

ABSTRACT

OBJECTIVE: PCSK9 (proprotein convertase subtilisin-kexin 9) enhances the degradation of the LDLR (low-density lipoprotein receptor) in endosomes/lysosomes. This study aimed to determine the sites of PCSK9 phosphorylation at Ser-residues and the consequences of such posttranslational modification on the secretion and activity of PCSK9 on the LDLR. Approach and Results: Fam20C (family with sequence similarity 20, member C) phosphorylates serines in secretory proteins containing the motif S-X-E/phospho-Ser, including the cholesterol-regulating PCSK9. In situ hybridization of Fam20C mRNA during development and in adult mice revealed a wide tissue distribution, including liver, but not small intestine. Here, we show that Fam20C phosphorylates PCSK9 at Serines 47, 666, 668, and 688. In hepatocytes, phosphorylation enhances PCSK9 secretion and maximizes its induced degradation of the LDLR via the extracellular and intracellular pathways. Replacing any of the 4 Ser by the phosphomimetic Glu or Asp enhanced PCSK9 activity only when the other sites are phosphorylated, whereas Ala substitutions reduced it, as evidenced by Western blotting, Elisa, and LDLR-immunolabeling. This newly uncovered PCSK9/LDLR regulation mechanism refines our understanding of the implication of global PCSK9 phosphorylation in the modulation of LDL-cholesterol and rationalizes the consequence of natural mutations, for example, S668R and E670G. Finally, the relationship of Ser-phosphorylation to the implication of PCSK9 in regulating LDL-cholesterol in the neurological Fragile X-syndrome disorder was investigated. CONCLUSIONS: Ser-phosphorylation of PCSK9 maximizes both its secretion and activity on the LDLR. Mass spectrometric approaches to measure such modifications were developed and applied to quantify the levels of bioactive PCSK9 in human plasma under normal and pathological conditions.


Subject(s)
Calcium-Binding Proteins/genetics , Extracellular Matrix Proteins/genetics , Gene Expression Regulation , Hyperlipoproteinemia Type II/genetics , Proprotein Convertase 9/metabolism , Receptors, LDL/genetics , Animals , Blotting, Western , Cells, Cultured , Hep G2 Cells , Hepatocytes/metabolism , Humans , Hyperlipoproteinemia Type II/physiopathology , In Situ Hybridization/methods , Male , Mice , Mice, Knockout , Microscopy, Confocal , Phosphorylation/genetics , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction/methods , Receptors, LDL/metabolism , Sensitivity and Specificity
10.
Can J Physiol Pharmacol ; 98(7): 477-481, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32119574

ABSTRACT

Recent studies in prostate cancer have identified PACE4, a proprotein convertase enzyme, as an emerging therapeutic target. Inhibition of PACE4-altCT, an oncogenic isoform of PACE4, using molecular or pharmacological approaches results in decreased cell proliferation and tumor progression in xenograft models. Although several validations have confirmed PACE4-altCT as a novel therapeutic target, the transcriptional regulation of PACE4 isoforms and mechanism of action remain a challenge. Previously, it has been reported that the human PACE4 promoter possesses potential binding sites for the E2F family of transcription factors, all of which are involved in cell cycle regulation and synthesis of DNA in mammalian cells. Therefore, we attempted to conduct in-depth evaluation of E2Fs on PACE4 and PACE4 isoform expression in prostate cancer. We conducted in vitro molecular silencing studies in various prostate cancer cell lines and determined the change in PACE4 expression levels. The results clearly show that the E2Fs alone do not alter PACE4 expression.


Subject(s)
Adenocarcinoma/genetics , E2F Transcription Factors/metabolism , Gene Expression Regulation, Neoplastic , Proprotein Convertases/genetics , Prostatic Neoplasms/genetics , Serine Endopeptidases/genetics , Adenocarcinoma/pathology , Cell Line, Tumor , Datasets as Topic , E2F Transcription Factors/genetics , Gene Expression Profiling , Gene Knockdown Techniques , Humans , Male , Prostatic Neoplasms/pathology , Protein Isoforms/genetics , Up-Regulation
11.
Int J Mol Sci ; 21(12)2020 Jun 18.
Article in English | MEDLINE | ID: mdl-32570961

ABSTRACT

Normal pregnancy is associated with dramatic increases in uterine blood flow to facilitate the bidirectional maternal-fetal exchanges of respiratory gases and to provide sole nutrient support for fetal growth and survival. The mechanism(s) underlying pregnancy-associated uterine vasodilation remain incompletely understood, but this is associated with elevated estrogens, which stimulate specific estrogen receptor (ER)-dependent vasodilator production in the uterine artery (UA). The classical ERs (ERα and ERß) and the plasma-bound G protein-coupled ER (GPR30/GPER) are expressed in UA endothelial cells and smooth muscle cells, mediating the vasodilatory effects of estrogens through genomic and/or nongenomic pathways that are likely epigenetically modified. The activation of these three ERs by estrogens enhances the endothelial production of nitric oxide (NO), which has been shown to play a key role in uterine vasodilation during pregnancy. However, the local blockade of NO biosynthesis only partially attenuates estrogen-induced and pregnancy-associated uterine vasodilation, suggesting that mechanisms other than NO exist to mediate uterine vasodilation. In this review, we summarize the literature on the role of NO in ER-mediated mechanisms controlling estrogen-induced and pregnancy-associated uterine vasodilation and our recent work on a "new" UA vasodilator hydrogen sulfide (H2S) that has dramatically changed our view of how estrogens regulate uterine vasodilation in pregnancy.


Subject(s)
Estrogens/metabolism , Receptors, Estrogen/metabolism , Uterine Artery/pathology , Epigenesis, Genetic , Female , Humans , Nitric Oxide/metabolism , Pregnancy , Receptors, Estrogen/genetics , Uterine Artery/metabolism , Vasodilation
12.
J Biol Chem ; 2017 Nov 28.
Article in English | MEDLINE | ID: mdl-29184001

ABSTRACT

This article has been withdrawn by the authors. Figs 1C, 2A, and 2E contained some inadvertently mislabeled data. The authors state that the mislabeling does not affect the conclusions of the article.

13.
J Biol Chem ; 292(25): 10564-10573, 2017 06 23.
Article in English | MEDLINE | ID: mdl-28468828

ABSTRACT

Protein C, a secretory vitamin K-dependent anticoagulant serine protease, inactivates factors Va/VIIIa. It is exclusively synthesized in liver hepatocytes as an inactive zymogen (proprotein C). In humans, thrombin cleavage of the propeptide at PR221↓ results in activated protein C (APC; residues 222-461). However, the propeptide is also cleaved by a furin-like proprotein convertase(s) (PCs) at KKRSHLKR199↓ (underlined basic residues critical for the recognition by PCs), but the order of cleavage is unknown. Herein, we present evidence that at the surface of COS-1 cells, mouse proprotein C is first cleaved by the convertases furin, PC5/6A, and PACE4. In mice, this cleavage occurs at the equivalent site, KKRKILKR198↓, and requires the presence of Arg198 at P1 and a combination of two other basic residues at either P2 (Lys197), P6 (Arg193), or P8 (Lys191) positions. Notably, the thrombin-resistant R221A mutant is still cleaved by these PCs, revealing that convertase cleavage can precede thrombin activation. This conclusion was supported by the fact that the APC-specific activity in the medium of COS-1 cells is exclusively dependent on prior cleavage by the convertases, because both R198A and R221A lack protein C activity. Primary cultures of hepatocytes derived from wild-type or hepatocyte-specific furin, PC5/6, or complete PACE4 knock-out mice suggested that the cleavage of overexpressed proprotein C is predominantly performed by furin intracellularly and by all three proprotein convertases at the cell surface. Indeed, plasma analyses of single-proprotein convertase-knock-out mice showed that loss of the convertase furin or PC5/6 in hepatocytes results in a ∼30% decrease in APC levels, with no significant contribution from PACE4. We conclude that prior convertase cleavage of protein C in hepatocytes is critical for its thrombin activation.


Subject(s)
Hepatocytes/enzymology , Liver/enzymology , Proprotein Convertase 5/metabolism , Protein C/metabolism , Amino Acid Substitution , Animals , COS Cells , Chlorocebus aethiops , Enzyme Activation/physiology , Hep G2 Cells , Humans , Mice , Mice, Knockout , Mutation, Missense , Proprotein Convertase 5/genetics , Proprotein Convertases/genetics , Proprotein Convertases/metabolism , Protein C/genetics , Serine Endopeptidases/genetics , Serine Endopeptidases/metabolism , Thrombin/genetics , Thrombin/metabolism
14.
Nano Lett ; 17(7): 4502-4507, 2017 07 12.
Article in English | MEDLINE | ID: mdl-28621537

ABSTRACT

Development of new synthetic methods for the modification of nanostructures has accelerated materials design advances to furnish complex architectures. Structures based on one-dimensional (1D) silicon (Si) structures synthesized using top-down and bottom-up methods are especially prominent for diverse applications in chemistry, physics, and medicine. Yet further elaboration of these structures with distinct metal-based and polymeric materials, which could open up new opportunities, has been difficult. We present a general electrochemical method for the deposition of conformal layers of various materials onto high aspect ratio Si micro- and nanowire arrays. The electrochemical deposition of a library of coaxial layers comprising metals, metal oxides, and organic/inorganic semiconductors demonstrate the materials generality of the synthesis technique. Depositions may be performed on wire arrays with varying diameter (70 nm to 4 µm), pitch (5 µ to 15 µ), aspect ratio (4:1 to 75:1), shape (cylindrical, conical, hourglass), resistivity (0.001-0.01 to 1-10 ohm/cm2), and substrate orientation. Anisotropic physical etching of wires with one or more coaxial shells yields 1D structures with exposed tips that can be further site-specifically modified by an electrochemical deposition approach. The electrochemical deposition methodology described herein features a wafer-scale synthesis platform for the preparation of multifunctional nanoscale devices based on a 1D Si substrate.

15.
J Biol Chem ; 291(47): 24676-24687, 2016 Nov 18.
Article in English | MEDLINE | ID: mdl-27758865

ABSTRACT

The mechanism of LDL receptor (LDLR) degradation mediated by the proprotein convertase subtilisin/kexin type 9 (PCSK9) has been extensively studied; however, many steps within this process remain unclear and still require characterization. Recent studies have shown that PCSK9 lacking its Cys/His-rich domain can still promote LDLR internalization, but the complex does not reach the lysosome suggesting the presence of an additional interaction partner(s). In this study we carried out an unbiased screening approach to identify PCSK9-interacting proteins in the HepG2 cells' secretome using co-immunoprecipitation combined with mass spectrometry analyses. Several interacting proteins were identified, including glypican-3 (GPC3), phospholipid transfer protein, matrilin-3, tissue factor pathway inhibitor, fibrinogen-like 1, and plasminogen activator inhibitor-1. We then validated these interactions by co-immunoprecipitation and Western blotting. Furthermore, functional validation was examined by silencing each candidate protein in HepG2 cells using short hairpin RNAs to determine their effect on LDL uptake and LDLR levels. Only GPC3 and phospholipid transfer protein silencing in HepG2 cells significantly increased LDL uptake in these cells and displayed higher total LDLR protein levels compared with control cells. Moreover, our study provides the first evidence that GPC3 can modulate the PCSK9 extracellular activity as a competitive binding partner to the LDLR in HepG2 cells.


Subject(s)
Carcinoma, Hepatocellular/metabolism , Glypicans/metabolism , Liver Neoplasms/metabolism , Neoplasm Proteins/metabolism , Proprotein Convertase 9/metabolism , Receptors, LDL/metabolism , Carcinoma, Hepatocellular/genetics , Glypicans/genetics , Hep G2 Cells , Humans , Lipoproteins, LDL/genetics , Lipoproteins, LDL/metabolism , Liver Neoplasms/genetics , Matrilin Proteins/genetics , Matrilin Proteins/metabolism , Neoplasm Proteins/genetics , Proprotein Convertase 9/genetics , Protein Binding , Receptors, LDL/genetics
16.
Mol Plant Microbe Interact ; 30(2): 138-149, 2017 02.
Article in English | MEDLINE | ID: mdl-28027026

ABSTRACT

Increased resilience of pasture grasses mediated by fungal Epichloë endophytes is crucial to pastoral industries. The underlying mechanisms are only partially understood and likely involve very different activities of the endophyte in different plant tissues and responses of the plant to these. We analyzed the transcriptomes of Epichloë festucae and its host, Lolium perenne, in host tissues of different function and developmental stages. The endophyte contributed approximately 10× more to the transcriptomes than to the biomass of infected tissues. Proliferating mycelium in growing host tissues highly expressed genes involved in hyphal growth. Nonproliferating mycelium in mature plant tissues, transcriptionally equally active, highly expressed genes involved in synthesizing antiherbivore compounds. Transcripts from the latter accounted for 4% of fungal transcripts. Endophyte infection systemically but moderately increased transcription of L. perenne genes with roles in hormone biosynthesis and perception as well as stress and pathogen resistance while reducing expression of genes involved in photosynthesis. There was a good correlation between transcriptome-based observations and physiological observations. Our data indicate that the fitness-enhancing effects of the endophyte are based both on its biosynthetic activities, predominantly in mature host tissues, and also on systemic alteration of the host's hormonal responses and induction of stress response genes. [Formula: see text] Copyright © 2017 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .


Subject(s)
Endophytes/physiology , Environment , Epichloe/physiology , Host-Pathogen Interactions , Lolium/immunology , Lolium/microbiology , Plant Growth Regulators/metabolism , Cell Nucleus/metabolism , Chloroplasts/metabolism , DNA, Plant/metabolism , Endophytes/genetics , Epichloe/genetics , Gene Expression Profiling , Gene Expression Regulation, Plant , Genes, Fungal , Herbivory , Hyphae/genetics , Lolium/growth & development , Open Reading Frames/genetics , Plant Diseases/genetics , Plant Diseases/microbiology , Plant Proteins/metabolism , Symbiosis/genetics , Transcription, Genetic , Transcriptome/genetics
17.
PLoS Pathog ; 11(11): e1005261, 2015.
Article in English | MEDLINE | ID: mdl-26545254

ABSTRACT

Human coronaviruses (HCoV) are respiratory pathogens that may be associated with the development of neurological diseases, in view of their neuroinvasive and neurotropic properties. The viral spike (S) glycoprotein is a major virulence factor for several coronavirus species, including the OC43 strain of HCoV (HCoV-OC43). In an attempt to study the role of this protein in virus spread within the central nervous system (CNS) and neurovirulence, as well as to identify amino acid residues important for such functions, we compared the sequence of the S gene found in the laboratory reference strain HCoV-OC43 ATCC VR-759 to S sequences of viruses detected in clinical isolates from the human respiratory tract. We identified one predominant mutation at amino acid 758 (from RRSR↓ G758 to RRSR↓R758), which introduces a putative furin-like cleavage (↓) site. Using a molecular cDNA infectious clone to generate a corresponding recombinant virus, we show for the first time that such point mutation in the HCoV-OC43 S glycoprotein creates a functional cleavage site between the S1 and S2 portions of the S protein. While the corresponding recombinant virus retained its neuroinvasive properties, this mutation led to decreased neurovirulence while potentially modifying the mode of virus spread, likely leading to a limited dissemination within the CNS. Taken together, these results are consistent with the adaptation of HCoV-OC43 to the CNS environment, resulting from the selection of quasi-species harboring mutations that lead to amino acid changes in viral genes, like the S gene in HCoV-OC43, which may contribute to a more efficient establishment of a less pathogenic but persistent CNS infection. This adaptative mechanism could potentially be associated with human encephalitis or other neurological degenerative pathologies.


Subject(s)
Central Nervous System Diseases/virology , Coronavirus Infections/virology , Coronavirus OC43, Human/pathogenicity , Proprotein Convertases/metabolism , Spike Glycoprotein, Coronavirus/metabolism , Animals , Coronavirus OC43, Human/isolation & purification , Coronavirus OC43, Human/physiology , Glycoproteins/metabolism , Humans , Mice , Virulence
18.
Opt Express ; 25(7): 8326-8334, 2017 Apr 03.
Article in English | MEDLINE | ID: mdl-28380947

ABSTRACT

Zero-index metamaterials (ZIMs) offer unprecedented ways to manipulate the flow of light, and are of interest for wide range of applications including optical cloaking, super-coupling, and unconventional phase-matching properties in nonlinear optics. Impedance-matched ZIMs can be obtained through a photonic Dirac-cone (PDC) dispersion induced by an accidental degeneracy of an electric monopole and a transverse magnetic dipole mode at the center of the Brillouin zone. Therefore, PDC is very sensitive to fabrication imperfections. In this work, we propose and demonstrate fabrication-tolerant all-dielectric ZIM in telecom regime that supports near PDC dispersion over much wider parameter space than conventional designs. The prism device integrated with Si photonics is fabricated and measured for the verification.

19.
J Am Acad Dermatol ; 77(2): 310-317.e1, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28416342

ABSTRACT

BACKGROUND: Randomized, controlled trials demonstrated efficacy and safety of apremilast for moderate-to-severe plaque psoriasis and psoriatic arthritis. OBJECTIVE: Assess long-term safety of oral apremilast in psoriasis patients. METHODS: Safety findings are reported for 0 to ≥156 weeks from the Efficacy and Safety Trial Evaluating the Effects of Apremilast in Psoriasis (ESTEEM) 1 and 2. RESULTS: The 0 to ≥156-week apremilast-exposure period included 1184 patients treated twice daily with apremilast 30 mg (1902.2 patient-years). During 0 to ≤52 weeks, the adverse events (AEs) that occurred in ≥5% of patients included diarrhea, nausea, upper respiratory tract infection, nasopharyngitis, tension headache, and headache. From 0 to ≥156 weeks, no new AEs (affecting ≥5% of the population) were reported. AEs, serious AEs, and study drug discontinuations caused by AEs did not increase with long-term exposure. During the 0 to ≥156-week period, the rates of major cardiac events (exposure-adjusted incidence rate [EAIR] 0.5/100 patient-years), malignancies (EAIR 1.2/100 patient-years), depression (EAIR 1.8/100 patient-years), or suicide attempts (EAIR 0.1/100 patient-years) did not increase in comparison with the rates found during the 0 to ≤52-week period. No serious opportunistic infections, reactivation of tuberculosis, or clinically meaningful effects on laboratory measurements were reported. LIMITATIONS: This study had a high dropout rate (21% of patients ongoing >156 weeks); most were unrelated to safety concerns. CONCLUSIONS: Apremilast demonstrated an acceptable safety profile and was generally well tolerated for ≥156 weeks.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Cardiovascular Diseases/epidemiology , Depression/epidemiology , Neoplasms/epidemiology , Psoriasis/drug therapy , Thalidomide/analogs & derivatives , Adult , Diarrhea/chemically induced , Female , Headache/chemically induced , Humans , Incidence , Male , Middle Aged , Nasopharyngitis/chemically induced , Nausea/chemically induced , Respiratory Tract Infections/chemically induced , Suicide, Attempted/statistics & numerical data , Tension-Type Headache/chemically induced , Thalidomide/adverse effects , Time Factors
20.
Mol Cell Proteomics ; 14(11): 2857-77, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26330543

ABSTRACT

Macrophages provide the first line of host immune defense. Their activation triggers the secretion of pro-inflammatory cytokines and chemokines recruiting other immune cells. In cancer, macrophages present an M2 anti-inflammatory phenotype promoting tumor growth. In this way, strategies need to be develop to reactivate macrophages. Previously thought to be expressed only in cells with a neural/neuroendocrine phenotype, the proprotein convertase 1/3 has been shown to also be expressed in macrophages and regulated as a function of the Toll-like receptor immune response. Here, we investigated the intracellular impact of the down-regulation of the proprotein convertase 1/3 in NR8383 macrophages and confirmed the results on macrophages from PC1/3 deficient mice. A complete proteomic study of secretomes and intracellular proteins was undertaken and revealed that inhibition of proprotein convertase 1/3 orient macrophages toward an M1 activated phenotype. This phenotype is characterized by filopodial extensions, Toll-like receptor 4 MyD88-dependent signaling, calcium entry augmentation and the secretion of pro-inflammatory factors. In response to endotoxin/lipopolysaccharide, these intracellular modifications increased, and the secreted factors attracted naïve T helper lymphocytes to promote the cytotoxic response. Importantly, the application of these factors onto breast and ovarian cancer cells resulted in a decrease viability or resistance. Under inhibitory conditions using interleukin 10, PC1/3-knockdown macrophages continued to secrete inflammatory factors. These data indicate that targeted inhibition of proprotein convertase 1/3 could represent a novel type of immune therapy to reactivate intra-tumoral macrophages.


Subject(s)
Immunotherapy/methods , Macrophages, Alveolar/immunology , Macrophages, Peritoneal/immunology , Proprotein Convertase 1/antagonists & inhibitors , Animals , CD4-Positive T-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/pathology , CD8-Positive T-Lymphocytes/drug effects , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/pathology , Calcium/metabolism , Cell Line , Cell Line, Tumor , Cytokines/biosynthesis , Cytokines/immunology , Gene Expression Regulation , Humans , Killer Cells, Natural/drug effects , Killer Cells, Natural/immunology , Killer Cells, Natural/pathology , Lipopolysaccharides/pharmacology , Macrophages, Alveolar/cytology , Macrophages, Alveolar/drug effects , Macrophages, Peritoneal/cytology , Macrophages, Peritoneal/drug effects , Mice , Mice, Knockout , Myeloid Differentiation Factor 88/genetics , Myeloid Differentiation Factor 88/immunology , Primary Cell Culture , Proprotein Convertase 1/genetics , Proprotein Convertase 1/immunology , Protein Array Analysis , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , Rats , Signal Transduction , T-Lymphocytes, Helper-Inducer/drug effects , T-Lymphocytes, Helper-Inducer/immunology , T-Lymphocytes, Helper-Inducer/pathology , Toll-Like Receptor 4/genetics , Toll-Like Receptor 4/immunology
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