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1.
Curr Pain Headache Rep ; 24(11): 73, 2020 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-33098008

RESUMEN

PURPOSE OF REVIEW: Multimodal pain management is the most effective way to treat postsurgical pain. However, the use of opioids for acute pain management has unfortunately been a significant contributor to the current opioid epidemic. The use of opioids should be limited and only considered a "rescue" pain medication after other modalities of pain management have been utilized. RECENT FINDINGS: It may be difficult to curtail the use of opioids in the treatment of chronic pain; however, in the postsurgical setting, there is compelling evidence that an opioid-centric analgesic approach is not necessary for good patient outcomes and healthcare cost benefits. Opioid-related adverse effects are the leading cause of preventable harm in the hospital setting. After the realization in recent years of the many harmful effects of opioids, alternative regimens including the use of multimodal analgesia have become a standard practice in acute pain management. Exparel, a long-lasting liposomal bupivacaine local anesthetic agent, has many significant benefits in the management of postoperative pain. Overall, the literature suggests that Exparel may be a significant component for postoperative multimodal pain control owing to its efficacy and long duration of action.


Asunto(s)
Anestésicos Locales/administración & dosificación , Bupivacaína/administración & dosificación , Manejo del Dolor/métodos , Dolor Postoperatorio/tratamiento farmacológico , Preparaciones de Acción Retardada/administración & dosificación , Humanos , Liposomas
2.
Curr Pain Headache Rep ; 23(9): 67, 2019 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-31359193

RESUMEN

PURPOSE OF REVIEW: Anticoagulant use among patients is prevalent and increasing. It is important for anesthesiologists to be aware of patients on anticoagulants while performing regional anesthesia. RECENT FINDINGS: In recent years, the FDA has approved many new anticoagulants. With new drugs coming to the market, new side effect profiles should be considered when treating patients, especially when using regional anesthesia. Both ASRA and European agencies have laid out recommendations regarding anticoagulant use and neuraxial/regional techniques. Regarding newer anticoagulants, the guidelines for discontinuation prior to neuraxial injection are based on pharmacokinetics, including half-life duration for each drug. While each clinical scenario requires an individualized approach, general guidelines can serve as a starting point to help with anesthetic planning and potentially improve patient safety in this evolving field.


Asunto(s)
Anestesia de Conducción/métodos , Anticoagulantes/administración & dosificación , Medicina Basada en la Evidencia/métodos , Administración Oral , Anestesia de Conducción/efectos adversos , Anticoagulantes/efectos adversos , Medicina Basada en la Evidencia/tendencias , Hemorragia/inducido químicamente , Hemorragia/diagnóstico , Hemorragia/prevención & control , Humanos , Factores de Riesgo
3.
J Biol Chem ; 292(38): 15849-15858, 2017 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-28743743

RESUMEN

The HIV-1 envelope (Env) is a glycoprotein consisting of a trimer of heterodimers containing gp120 and gp41 subunits that mediates virus entry and is a major target of broadly neutralizing antibodies (bnAbs) developed during infection in some individuals. The engagement of the HIV-1 gp120 glycoprotein to the host CD4 protein triggers conformational changes in gp120 that allow its binding to co-receptors and is necessary for virus entry to establish infection. Native-like HIV-1 Env immunogens representing distinct clades have been proposed to improve immunogenicity. In the present study, we examined the basis of resistance of an HIV-1 B/C recombinant Env (LT5.J4b12C) to non-neutralizing antibodies targeting CD4-induced Env epitopes in the presence of soluble CD4 (sCD4). Using native polyacrylamide gel shift assay and negative-stain EM, we found that the prefusion conformational state of LT5.J4b12C trimeric Env was largely unaffected in the presence of excess sCD4 with most Env trimers appearing to be in a ligand-free state. This resistance to CD4-induced conformational changes was associated with a lower affinity for CD4. Moreover, the LT5.J4b12C trimeric Env preferentially bound to the neutralizing antibodies compared with non-neutralizing antibodies. Taken together, we report on an HIV-1 B/C recombinant, native-like trimeric Env protein that is highly resistant to CD4-induced conformational changes but displays epitopes recognized by a diverse array of bnAbs. Such features make this B/C recombinant trimeric Env a useful addition to the pool of other recently identified native-like HIV-1 Env trimers suitable for use as antigenic bait for bnAb isolation, structural studies, and use as potential immunogens.


Asunto(s)
Antígenos CD4/química , Antígenos CD4/farmacología , VIH-1 , Multimerización de Proteína , Proteínas Recombinantes/química , Productos del Gen env del Virus de la Inmunodeficiencia Humana/química , Secuencia de Aminoácidos , Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos ampliamente neutralizantes , Antígenos CD4/metabolismo , Epítopos/inmunología , Células HEK293 , Anticuerpos Anti-VIH , Humanos , Modelos Moleculares , Conformación Proteica , Estabilidad Proteica/efectos de los fármacos , Estructura Cuaternaria de Proteína , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/metabolismo , Solubilidad , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología , Productos del Gen env del Virus de la Inmunodeficiencia Humana/metabolismo
4.
J Gen Virol ; 99(3): 379-392, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29458681

RESUMEN

Broadly neutralizing antibodies (bnAbs) have been considered to be potent therapeutic tools and potential vaccine candidates to enable protection against various clades of human immunodeficiency virus (HIV). The generation of bnAbs has been associated with enhanced exposure to antigen, high viral load and low CD4+ T cell counts, among other factors. However, only limited data are available on the generation of bnAbs in viraemic non-progressors that demonstrate moderate to high viraemia. Further, since HIV-1 subtype C viruses account for more than 50 % of global HIV infections, the identification of bnAbs with novel specificities is crucial to enable the development of potent tools to aid in HIV therapy and prevention. In the present study, we analysed and compared the neutralization potential of responses in 70 plasma samples isolated from ART-naïve HIV-1 subtype C-infected individuals with various disease progression profiles against a panel of 30 pseudoviruses. Among the seven samples that exhibited a neutralization breadth of ≥70 %, four were identified as 'elite neutralizers', and three of these were from viraemic non-progressors while the fourth was from a typical progressor. Analysis of the neutralization specificities revealed that none of the four elite neutralizers were reactive to epitopes in the membrane proximal external region (MPER), CD4-binding site and V1V2 or V3 glycan. However, two of the four elite neutralizers exhibited enhanced sensitivity towards viruses lacking N332 glycan, indicating high neutralization potency. Overall, our findings indicate that the identification of potent neutralization responses with distinct epitope specificities is possible from the as yet unexplored Indian population, which has a high prevalence of HIV-1 subtype C infection.

5.
Biochim Biophys Acta Gen Subj ; 1862(8): 1729-1741, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29746960

RESUMEN

BACKGROUND: p300 (KAT3B) lysine acetyltransferase activity is modulated under different physiological and pathological contexts through the induction of trans-autoacetylation. This phenomenon is mediated by several factors, mechanisms of which are not fully understood. METHODS: Through acetyltransferase assays using full-length, baculovirus-expressed KATs, the specificity of NPM1-mediated enhancement of p300 autoacetylation was tested. Chaperone assays and tryptophan fluorescence studies were performed to evaluate the NPM1-induced protein folding. The NPM1 oligomer-defective mutant characterization was done by glutaraldehyde-crosslinking. The small-molecule inhibitor of NPM1 oligomerization was used to confirm the absolute requirement of multimeric NPM1 in vivo. Immunohistochemistry analysis of oral cancer patient samples was done to uncover the pathophysiological significance of NPM1-induced p300 autoacetylation. RESULTS: We find that the histone chaperone NPM1 is a specific inducer of p300 autoacetylation. Distinct from its histone chaperone activity, NPM1 is a molecular chaperone of p300. The biophysical experiments suggest that there is a reversible binding between NPM1 and p300 which can modulate p300 acetyltransferase activity. Disruption of NPM1 oligomerization suggests that oligomeric NPM1 is essential for the induction of p300 autoacetylation. Significantly, we observe a concomitant hyper-autoacetylation of p300 with overexpression of NPM1 in oral cancer samples. CONCLUSION: NPM1 can specifically modulate p300 acetyltransferase activity through the enhancement of autoacetylation. The molecular chaperone activity and oligomerization of NPM1 play a pivotal role in this phenomenon. GENERAL SIGNIFICANCE: NPM1 is overexpressed in several solid cancers, the significance of which is unknown. Induction of p300 autoacetylation could be the cause of NPM1-mediated tumorigenicity.


Asunto(s)
Proteína p300 Asociada a E1A/química , Proteína p300 Asociada a E1A/metabolismo , Histonas/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Pliegue de Proteína , Multimerización de Proteína , Neoplasias de la Lengua/metabolismo , Acetilación , Humanos , Nucleofosmina , Unión Proteica , Conformación Proteica , Neoplasias de la Lengua/patología , Células Tumorales Cultivadas
6.
J Virol ; 90(7): 3446-57, 2016 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-26763999

RESUMEN

UNLABELLED: Broadly neutralizing antibodies isolated from infected patients who are elite neutralizers have identified targets on HIV-1 envelope (Env) glycoprotein that are vulnerable to antibody neutralization; however, it is not known whether infection established by the majority of the circulating clade C strains in Indian patients elicit neutralizing antibody responses against any of the known targets. In the present study, we examined the specificity of a broad and potent cross-neutralizing plasma obtained from an Indian elite neutralizer infected with HIV-1 clade C. This plasma neutralized 53/57 (93%) HIV pseudoviruses prepared with Env from distinct HIV clades of different geographical origins. Mapping studies using gp120 core protein, single-residue knockout mutants, and chimeric viruses revealed that G37080 broadly cross-neutralizing (BCN) plasma lacks specificities to the CD4 binding site, gp41 membrane-proximal external region, N160 and N332 glycans, and R166 and K169 in the V1-V3 region and are known predominant targets for BCN antibodies. Depletion of G37080 plasma with soluble trimeric BG505-SOSIP.664 Env (but with neither monomeric gp120 nor clade C membrane-proximal external region peptides) resulted in significant reduction of virus neutralization, suggesting that G37080 BCN antibodies mainly target epitopes on cleaved trimeric Env. Further examination of autologous circulating Envs revealed the association of mutation of residues in the V1 loop that contributed to neutralization resistance. In summary, we report the identification of plasma antibodies from a clade C-infected elite neutralizer that mediate neutralization breadth via epitopes on trimeric gp120 not yet reported and confer autologous neutralization escape via mutation of residues in the V1 loop. IMPORTANCE: A preventive vaccine to protect against HIV-1 is urgently needed. HIV-1 envelope glycoproteins are targets of neutralizing antibodies and represent a key component for immunogen design. The mapping of epitopes on viral envelopes vulnerable to immune evasion will aid in defining targets of vaccine immunogens. We identified novel conformational epitopes on the viral envelope targeted by broadly cross-neutralizing antibodies elicited in natural infection in an elite neutralizer infected with HIV-1 clade C. Our data extend our knowledge on neutralizing epitopes associated with virus escape and potentially contribute to immunogen design and antibody-based prophylactic therapy.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Anti-VIH/sangre , Proteína gp120 de Envoltorio del VIH/inmunología , Infecciones por VIH/inmunología , VIH-1/inmunología , Evasión Inmune/inmunología , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología , Vacunas contra el SIDA/inmunología , Línea Celular , Mapeo Epitopo , Epítopos/inmunología , Células HEK293 , Anticuerpos Anti-VIH/inmunología , Infecciones por VIH/virología , Humanos , India
7.
Retrovirology ; 13(1): 41, 2016 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-27307004

RESUMEN

BACKGROUND: Broadly neutralizing antibodies to HIV-1 elicited in infected individuals evolves through shifts in their molecular specificities to viral envelope (Env) in the disease course. Recently, we showed that resistance of circulating HIV-1 clade C to the autologous plasma obtained from one Indian elite neutralizer is associated with mutations in V1 loop. In the present study, we examined the genetic attributes associated with exceptional sensitivity of pseudoviruses expressing an env gene obtained from the follow up visit contemporaneous plasma of the same donor. RESULTS: Examination of chimeric autologous Envs, we found that enhanced neutralization sensitivity is associated with mutations in the V3/C3 region. A positive association between V3/C3 mutation mediated enhanced autologous neutralization of autologous viruses with their sensitivity to both neutralizing and non-neutralizing monoclonal antibodies was found. Interestingly, we found that depletion of autologous plasma with trimeric and monomeric Envs conferred the sensitive Env with resistance indicating that mutations in V3/C3 region altered Env conformation towards optimal exposure of epitopes targeted by the neutralizing and non-neutralizing antibodies. CONCLUSION: In summary, we found distinct vulnerabilities associated with evasion of circulating viruses to broadly neutralizing antibodies mounted in an Indian elite neutralizer.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Anti-VIH/inmunología , Proteína gp120 de Envoltorio del VIH/genética , Infecciones por VIH/inmunología , VIH-1/inmunología , Mutación , Fragmentos de Péptidos/genética , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología , Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/sangre , Epítopos , Anticuerpos Anti-VIH/sangre , Infecciones por VIH/virología , VIH-1/genética , Humanos , Evasión Inmune , Pruebas de Neutralización , Plasma/inmunología , Plasma/virología , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genética
8.
Retrovirology ; 13(1): 60, 2016 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-27576440

RESUMEN

The glycan supersite centered on N332 in the V3 base of the HIV-1 envelope (Env) is a target for broadly neutralizing antibodies (bnAbs) such as PGT121 and PGT128. In this study, we examined the basis of resistance of HIV-1 clade C Envs obtained from broadly cross neutralizing (BCN) plasma of an Indian donor with N332 specificity. Pseudotyped viruses expressing autologous envs were found to be resistant to autologous BCN plasma as well as to PGT121 and PGT128 mAbs despite the majority of Envs containing an intact N332 residue. While resistance of one of the Envs to neutralization by autologous plasma antibodies with shorter V1 loop length was found to be correlated with a N332S mutation, resistance to neutralization of rest of the Envs was found to be associated with longer V1 loop length and acquisition of protective N-glycans. In summary, we show evidence of escape of circulating HIV-1 clade C in an individual from autologous BCN antibodies by three distinct mechanisms.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Anti-VIH/inmunología , Proteína gp120 de Envoltorio del VIH/inmunología , Infecciones por VIH/inmunología , VIH-1/inmunología , Fragmentos de Péptidos/inmunología , Polisacáridos/inmunología , Anticuerpos Anti-VIH/química , Proteína gp120 de Envoltorio del VIH/química , Proteína gp120 de Envoltorio del VIH/genética , Infecciones por VIH/virología , VIH-1/genética , VIH-1/fisiología , Humanos , Mutación , Pruebas de Neutralización , Fragmentos de Péptidos/química , Fragmentos de Péptidos/genética , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología
9.
J Neurooncol ; 123(2): 225-35, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25944386

RESUMEN

Insulin like growth factor binding protein 2 (IGFBP2) is highly up regulated in glioblastoma (GBM) tissues and has been one of the prognostic indicators. There are compelling evidences suggesting important roles for IGFBP2 in glioma cell proliferation, migration and invasion. Extracellular IGFBP2 through its carboxy terminal arginine glycine aspartate (RGD) motif can bind to cell surface α5ß1 integrins and activate pathways downstream to integrin signaling. This IGFBP2 activated integrin signaling is known to play a crucial role in IGFBP2 mediated invasion of glioma cells. Hence a molecular inhibitor of carboxy terminal domain of IGFBP2 which can inhibit IGFBP2-cell surface interaction is of great therapeutic importance. In an attempt to develop molecular inhibitors of IGFBP2, we screened single chain variable fragment (scFv) phage display libraries, Tomlinson I (Library size 1.47 × 10(8)) and Tomlinson J (Library size 1.37 × 10(8)) using human recombinant IGFBP2. After screening we obtained three IGFBP2 specific binders out of which one scFv B7J showed better binding to IGFBP2 at its carboxy terminal domain, blocked IGFBP2-cell surface association, reduced activity of matrix metalloprotease 2 in the conditioned medium of glioma cells and inhibited IGFBP2 induced migration and invasion of glioma cells. We demonstrate for the first time that in vitro inhibition of extracellular IGFBP2 activity by using human scFv results in significant reduction of glioma cell migration and invasion. Therefore, the inhibition of IGFBP2 can serve as a potential therapeutic strategy in the management of GBM.


Asunto(s)
Neoplasias Encefálicas/prevención & control , Adhesión Celular , Movimiento Celular , Glioma/prevención & control , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/antagonistas & inhibidores , Anticuerpos de Cadena Única/farmacología , Apoptosis , Western Blotting , Neoplasias Encefálicas/inmunología , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Proliferación Celular , Ensayo de Inmunoadsorción Enzimática , Regulación Neoplásica de la Expresión Génica , Glioma/inmunología , Glioma/metabolismo , Glioma/patología , Humanos , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/inmunología , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 2 de la Matriz/metabolismo , Invasividad Neoplásica , Biblioteca de Péptidos , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal , Anticuerpos de Cadena Única/inmunología , Resonancia por Plasmón de Superficie , Células Tumorales Cultivadas
10.
Inorg Chem ; 54(1): 253-64, 2015 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-25496358

RESUMEN

Platinum(II) complexes [Pt(pap)(an-cat)] (1) and [Pt(pap)(py-cat)] (2) with 2-(phenylazo)pyridine (pap), 4-[2-[(anthracen-9-ylmethylene)amino]ethyl]benzene-1,2-diol (H2an-cat), and 4-[2-[(pyren-1-ylmethylene)amino]ethyl]benzene-1,2-diol (H2py-cat) were prepared, and their photoinduced cytotoxicity was studied. The complexes were found to release catecholate ligand in the presence of excess glutathione (GSH), resulting in cellular toxicity in the cancer cells. The catecholate complex [Pt(pap)(cat)] (3) was prepared and used as a control. Complex 3, which is structurally characterized by X-ray crystallography, has platinum(II) in a distorted square-planar geometry. The complexes are redox-active, showing responses near 0.6 and 1.0 V versus SCE in N,N-dimethylformamide/0.1 M tetrabutylammonium perchlorate corresponding to a two-step catechol oxidation process and at -0.3 and -1.3 V for reduction of the pap ligand. Complex 1 showed remarkable light-induced cytotoxicity in HaCaT (human skin keratinocytes) and MCF-7 (human breast cancer) cells, giving IC50 value of ∼5 µM in visible light of 400-700 nm and >40 µM in the dark. The 2',7'-dichlorofluorescein diacetate (DCFDA) assay showed the generation of reactive oxygen species (ROS), which seems to trigger apoptosis, as is evident from the annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) assay. The fluorescence microscopic images showed significant nuclear localization of the complexes and free ligands. A mechanistic study revealed possible reduction of the coordinated azo bond of pap by cellular GSH, releasing the catecholate ligand and resulting in remarkable photochemotherapeutic action of the complexes.


Asunto(s)
Catecoles/toxicidad , Citotoxinas/farmacología , Glutatión/metabolismo , Queratinocitos/efectos de los fármacos , Compuestos Organoplatinos/farmacología , Fármacos Fotosensibilizantes/farmacología , Apoptosis/efectos de los fármacos , Derivados del Benceno/química , Transporte Biológico , Catecoles/química , Línea Celular Tumoral , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Núcleo Celular/efectos de la radiación , Citotoxinas/síntesis química , Dimetilformamida/química , Fluoresceínas , Colorantes Fluorescentes , Glutatión/farmacología , Humanos , Queratinocitos/metabolismo , Queratinocitos/patología , Queratinocitos/efectos de la radiación , Ligandos , Luz , Células MCF-7 , Compuestos Organoplatinos/síntesis química , Oxidación-Reducción , Fármacos Fotosensibilizantes/síntesis química , Piridinas/química , Compuestos de Amonio Cuaternario/química , Especies Reactivas de Oxígeno/agonistas , Especies Reactivas de Oxígeno/metabolismo
11.
Nanomedicine ; 11(4): 969-81, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25659647

RESUMEN

Multidrug resistance is a major therapeutic challenge faced in the conventional chemotherapy. Nanocarriers are beneficial in the transport of chemotherapeutics by their ability to bypass the P-gp efflux in cancers. Most of the P-gp inhibitors under phase II clinical trial are facing failures and hence there is a need to develop a suitable carrier to address P-gp efflux in cancer therapy. Herein, we prepared novel protamine and carboxymethyl cellulose polyelectrolyte multi-layered nanocapsules modified with Fe3O4 nanoparticles for the delivery of doxorubicin against highly drug resistant HeLa cells. The experimental results revealed that improved cellular uptake, enhanced drug intensity profile with greater percentage of apoptotic cells was attained when doxorubicin loaded magnetic nanocapsules were used in the presence of external magnetic field. Hence, we conclude that this magnetic field assisted nanocapsule system can be used for delivery of chemotherapeutics for potential therapeutic efficacy at minimal dose in multidrug resistant cancers. FROM THE CLINICAL EDITOR: Many cancer drugs fail when cancer cells become drug resistant. Indeed, multidrug resistance (MDR) is a major therapeutic challenge. One way that tumor cells attain MDR is by over expression of molecular pumps comprising of P-glycoprotein (P-gp) and multidrug resistant proteins (MRP), which can expel chemotherapeutic drugs out of the cells. In this study, the authors prepared novel protamine and carboxymethyl cellulose polyelectrolyte multi-layered nanocapsules modified with Fe3O4 nanoparticles for the delivery of doxorubicin. The results show that there was better drug delivery and efficacy even against MDR tumor cells.


Asunto(s)
Carboximetilcelulosa de Sodio , Doxorrubicina , Resistencia a Antineoplásicos/efectos de los fármacos , Nanopartículas de Magnetita/química , Nanocápsulas/economía , Neoplasias/tratamiento farmacológico , Protaminas , Carboximetilcelulosa de Sodio/química , Carboximetilcelulosa de Sodio/farmacología , Doxorrubicina/química , Doxorrubicina/farmacología , Células HeLa , Humanos , Neoplasias/metabolismo , Neoplasias/patología , Protaminas/química , Protaminas/farmacología
12.
Glycoconj J ; 31(6-7): 509-21, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25142811

RESUMEN

Glycan structure alterations during cancer regulate disease progression and represent clinical biomarkers. The study determined the degree to which changes in glycosyltransferase activities during cancer can be related to aberrant cell-surface tumor associated carbohydrate structures (TACA). To this end, changes in sialyltransferase (sialylT), fucosyltransferase (fucT) and galactosyltransferase (galT) activity were measured in normal and tumor tissue using a miniaturized enzyme activity assay and synthetic glycoconjugates bearing terminal LacNAc Type-I (Galß1-3GlcNAc), LacNAc Type-II (Galß1-4GlcNAc), and mucin core-1/Type-III (Galß1-3GalNAc) structures. These data were related to TACA using tissue microarrays containing 115 breast and 26 colon cancer specimen. The results show that primary human breast and colon tumors, but not adjacent normal tissue, express elevated ß1,3GalT and α2,3SialylT activity that can form α2,3SialylatedType-IIIglycans (Siaα2-3Galß1-3GalNAc). Prostate tumors did not exhibit such elevated enzymatic activities. α1,3/4FucT activity was higher in breast, but not in colon tissue. The enzymology based prediction of enhanced α2,3sialylated Type-III structures in breast tumors was verified using histochemical analysis of tissue sections and tissue microarrays. Here, the binding of two markers that recognize Galß1-3GalNAc (peanut lectin and mAb A78-G/A7) was elevated in breast tumor, but not in normal control, only upon sialidase treatment. These antigens were also upregulated in colon tumors though to a lesser extent. α2,3sialylatedType-III expression correlated inversely with patient HER2 expression and breast metastatic potential. Overall, enzymology measurements of glycoT activity predict truncated O-glycan structures in tumors. High expression of the α2,3sialylated T-antigen O-glycans occur in breast tumors. A transformation from linear core-1 glycan to other epitopes may accompany metastasis.


Asunto(s)
Antígenos de Neoplasias/química , Neoplasias de la Mama/inmunología , Glucosiltransferasas/metabolismo , Neoplasias de la Mama/patología , Femenino , Humanos , Miniaturización , Análisis de Matrices Tisulares
13.
J Neurooncol ; 116(3): 455-64, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24395346

RESUMEN

Insulin like growth factor binding protein 4 (IGFBP4) regulates growth and development of tissues and organs by negatively regulating IGF signaling. Among most cancers, IGFBP4 has growth inhibitory role and reported as a down-regulated gene, except for renal cell carcinoma, wherein IGFBP4 promotes tumor progression. IGFBP4 expression has been shown to be higher in increasing grades of astrocytoma. However, the functional role of IGFBP4 in gliomas has not been explored. Surgical biopsies of 20 normal brain and 198 astrocytoma samples were analyzed for IGFBP4 expression by qRT-PCR. Highest expression of IGFBP4 mRNA was seen in GBM tumors compared to control brain tissues (median log2 of 2.035, p < 0.0001). Immunohistochemical analysis of 53 tissue samples revealed predominant nuclear staining of IGFBP4, seen maximally in GBMs when compared to DA and AA tumors (median LI = 29.12 ± 16.943, p < 0.001). Over expression of IGFBP4 in U343 glioma cells resulted in up-regulation of molecules involved in tumor growth, EMT and invasion such as pAkt, pErk, Vimentin, and N-cadherin and down-regulation of E-cadherin. Functionally, IGFBP4 over expression in these cells resulted in increased proliferation, migration and invasion as assessed by MTT, transwell migration, and Matrigel invasion assays. These findings were confirmed upon IGFBP4 knockdown in U251 glioma cells. Our data suggest a pro-tumorigenic role for IGFBP4 in glioma.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Glioblastoma/patología , Proteína 4 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Animales , Astrocitoma/patología , Cadherinas/metabolismo , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Movimiento Celular/fisiología , Proliferación Celular , Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/fisiología , Humanos , Proteína 4 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Ratones , Proteína Oncogénica v-akt/metabolismo , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Estadísticas no Paramétricas , Vimentina/metabolismo
14.
Mol Cancer ; 12: 63, 2013 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-23767917

RESUMEN

BACKGROUND: Insulin like growth factor binding proteins modulate the mitogenic and pro survival effects of IGF. Elevated expression of IGFBP2 is associated with progression of tumors that include prostate, ovarian, glioma among others. Though implicated in the progression of breast cancer, the molecular mechanisms involved in IGFBP2 actions are not well defined. This study investigates the molecular targets and biological pathways targeted by IGFBP2 in breast cancer. METHODS: Transcriptome analysis of breast tumor cells (BT474) with stable knockdown of IGFBP2 and breast tumors having differential expression of IGFBP2 by immunohistochemistry was performed using microarray. Differential gene expression was established using R-Bioconductor package. For validation, gene expression was determined by qPCR. Inhibitors of IGF1R and integrin pathway were utilized to study the mechanism of regulation of ß-catenin. Immunohistochemical and immunocytochemical staining was performed on breast tumors and experimental cells, respectively for ß-catenin and IGFBP2 expression. RESULTS: Knockdown of IGFBP2 resulted in differential expression of 2067 up regulated and 2002 down regulated genes in breast cancer cells. Down regulated genes principally belong to cell cycle, DNA replication, repair, p53 signaling, oxidative phosphorylation, Wnt signaling. Whole genome expression analysis of breast tumors with or without IGFBP2 expression indicated changes in genes belonging to Focal adhesion, Map kinase and Wnt signaling pathways. Interestingly, IGFBP2 knockdown clones showed reduced expression of ß- catenin compared to control cells which was restored upon IGFBP2 re-expression. The regulation of ß-catenin by IGFBP2 was found to be IGF1R and integrin pathway dependent. Furthermore, IGFBP2 and ß-catenin are co-ordinately overexpressed in breast tumors and correlate with lymph node metastasis. CONCLUSION: This study highlights regulation of ß-catenin by IGFBP2 in breast cancer cells and most importantly, combined expression of IGFBP2 and ß-catenin is associated with lymph node metastasis of breast tumors.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Ganglios Linfáticos/patología , beta Catenina/genética , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Transformación Celular Neoplásica , Análisis por Conglomerados , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Metástasis Linfática , Interferencia de ARN , Transducción de Señal , beta Catenina/metabolismo
15.
Artículo en Inglés | MEDLINE | ID: mdl-24192375

RESUMEN

Neisseria meningitidis is the causative microorganism of many human diseases, including bacterial meningitis; together with Streptococcus pneumoniae, it accounts for approximately 80% of bacterial meningitis infections. The emergence of antibiotic-resistant strains of N. meningitidis has created a strong urgency for the development of new therapeutics, and the high-resolution structural elucidation of enzymes involved in cell metabolism represents a platform for drug development. Acetyl-CoA hydrolase is involved in multiple functions in the bacterial cell, including membrane synthesis, fatty-acid and lipid metabolism, gene regulation and signal transduction. Here, the first recombinant protein expression, purification and crystallization of a hexameric acetyl-CoA hydrolase from N. meningitidis are reported. This protein was crystallized using the hanging-drop vapour-diffusion technique at pH 8.5 and 290 K using ammonium phosphate as a precipitant. Optimized crystals diffracted to 2.0 Šresolution at the Australian Synchrotron and belonged to space group P2(1)3 (unit-cell parameters a = b = c = 152.2 Å), with four molecules in the asymmetric unit.


Asunto(s)
Acetil-CoA Hidrolasa/química , Acetil-CoA Hidrolasa/aislamiento & purificación , Proteínas Bacterianas/química , Proteínas Bacterianas/aislamiento & purificación , Neisseria meningitidis/enzimología , Cristalización , Electroforesis en Gel de Poliacrilamida , Humanos , Difracción de Rayos X
16.
Sci Data ; 10(1): 70, 2023 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-36737439

RESUMEN

We introduce Cháksu-a retinal fundus image database for the evaluation of computer-assisted glaucoma prescreening techniques. The database contains 1345 color fundus images acquired using three brands of commercially available fundus cameras. Each image is provided with the outlines for the optic disc (OD) and optic cup (OC) using smooth closed contours and a decision of normal versus glaucomatous by five expert ophthalmologists. In addition, segmentation ground-truths of the OD and OC are provided by fusing the expert annotations using the mean, median, majority, and Simultaneous Truth and Performance Level Estimation (STAPLE) algorithm. The performance indices show that the ground-truth agreement with the experts is the best with STAPLE algorithm, followed by majority, median, and mean. The vertical, horizontal, and area cup-to-disc ratios are provided based on the expert annotations. Image-wise glaucoma decisions are also provided based on majority voting among the experts. Cháksu is the largest Indian-ethnicity-specific fundus image database with expert annotations and would aid in the development of artificial intelligence based glaucoma diagnostics.


Asunto(s)
Glaucoma , Disco Óptico , Humanos , Algoritmos , Inteligencia Artificial , Fondo de Ojo , Glaucoma/diagnóstico por imagen , Disco Óptico/diagnóstico por imagen
17.
J Ayurveda Integr Med ; 14(6): 100806, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37857033

RESUMEN

BACKGROUND: Prediabetes is an intermediate state of hyperglycemia, which acts as a precursor to Diabetes mellitus if left untreated. Nisha (Curcuma longa) and Amalaki (Emblica officinalis) combination has been advocated as drugs of choice to treat the early manifestations of Diabetes mellitus. OBJECTIVE: This prospective, randomized, single-blind, placebo-controlled, comparative study was planned to assess the efficacy and safety of Nisha-Amalaki capsules in preventing progression to Diabetes mellitus in prediabetic patients when administered for 6 months. METHODS: The study was conducted on prediabetic participants randomized to receive either Nisha-Amalaki (500 mg) or placebo one capsule twice a day for six months. The effect of study medications on IDRS (Indian Diabetes Risk Score), BMI (Body Mass Index), blood sugar, serum insulin, HOMA-IR (Homeostasis Model Assessment-Estimated Insulin Resistance), HbA1c (glycated hemoglobin), oxidative markers, Ayurvedic symptoms and Quality of Life (QoL) scores was assessed at regular intervals. RESULTS: 58 of the 62 participants enrolled completed the study. Significant fall in IDRS score [p < 0.001], BMI [p < 0.001], fasting, and 2 h post-OGTT sugar, insulin, HbA1c, HOMA-IR, and oxidative stress markers [p < 0.001] was observed in patients receiving Nisha-Amalaki at 6 months. Ayurvedic symptoms and QoL scores also improved at 6 months in the treatment group. CONCLUSION: Treatment with Nisha-Amalaki capsules improved all study parameters including insulin sensitivity at 6 months as compared to placebo in prediabetic patients. Thus Nisha-Amalaki should be considered as prophylactic therapy in prediabetics to delay progression to diabetes.

18.
Cell Mol Gastroenterol Hepatol ; 15(5): 1219-1246, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36758798

RESUMEN

BACKGROUND & AIMS: Loss of AT-rich interactive domain-containing protein 1A (ARID1A) fosters acinar-to-ductal metaplasia (ADM) and pancreatic carcinogenesis by down-regulating transcription programs controlling acinar cell identity. However, how ARID1A reacts to metaplasia-triggering environmental cues remains elusive. Here, we aimed to elucidate the role of ARID1A in controlling ductal pancreatic gene signatures and deciphering hierarchical signaling cues determining ARID1A-dependent chromatin regulation during acinar cell reprogramming. METHODS: Acinar cell explants with differential ARID1A status were subjected to genome-wide expression analyses. The impact of epidermal growth factor receptor (EGFR) signaling, NFATc1 activity, and ARID1A status on acinar reprogramming processes were characterized by ex vivo ADM assays and transgenic mouse models. EGFR-dependent ARID1A chromatin binding was studied by chromatin immunoprecipitation sequencing analysis and cellular fractionation. RESULTS: EGFR signaling interferes with ARID1A-dependent transcription by inducing genome-wide ARID1A displacement, thereby phenocopying ARID1A loss-of-function mutations and inducing a shift toward ADM permissive ductal transcription programs. Moreover, we show that EGFR signaling is required to push ARID1A-deficient acinar cells toward a metaplastic phenotype. Mechanistically, we identified the transcription factor nuclear factor of activated T cells 1 (NFATc1) as the central regulatory hub mediating both EGFR signaling-induced genomic ARID1A displacement and the induction of ADM-promoting gene signatures in the absence of ARID1A. Consequently, pharmacologic inhibition of NFATc1 or its depletion in transgenic mice not only preserves genome-wide ARID1A occupancy, but also attenuates acinar metaplasia led by ARID1A loss. CONCLUSIONS: Our data describe an intimate relationship between environmental signaling and chromatin remodeling in orchestrating cell fate decisions in the pancreas, and illustrate how ARID1A loss influences transcriptional regulation in acinar cell reprogramming.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Ratones , Animales , Células Acinares/metabolismo , Cromatina , Neoplasias Pancreáticas/genética , Carcinoma Ductal Pancreático/genética , Reprogramación Celular , Factores de Transcripción/genética , Receptores ErbB/genética , Ratones Transgénicos , Metaplasia , Proteínas de Unión al ADN/genética , Factores de Transcripción NFATC/genética , Factores de Transcripción NFATC/metabolismo
19.
Cell Metab ; 35(12): 2119-2135.e5, 2023 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-37913768

RESUMEN

The rising pancreatic cancer incidence due to obesity and type 2 diabetes is closely tied to hyperinsulinemia, an independent cancer risk factor. Previous studies demonstrated reducing insulin production suppressed pancreatic intraepithelial neoplasia (PanIN) pre-cancerous lesions in Kras-mutant mice. However, the pathophysiological and molecular mechanisms remained unknown, and in particular it was unclear whether hyperinsulinemia affected PanIN precursor cells directly or indirectly. Here, we demonstrate that insulin receptors (Insr) in KrasG12D-expressing pancreatic acinar cells are dispensable for glucose homeostasis but necessary for hyperinsulinemia-driven PanIN formation in the context of diet-induced hyperinsulinemia and obesity. Mechanistically, this was attributed to amplified digestive enzyme protein translation, triggering of local inflammation, and PanIN metaplasia in vivo. In vitro, insulin dose-dependently increased acinar-to-ductal metaplasia formation in a trypsin- and Insr-dependent manner. Collectively, our data shed light on the mechanisms connecting obesity-driven hyperinsulinemia and pancreatic cancer development.


Asunto(s)
Carcinoma in Situ , Diabetes Mellitus Tipo 2 , Hiperinsulinismo , Insulinas , Neoplasias Pancreáticas , Ratones , Animales , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Receptor de Insulina/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Neoplasias Pancreáticas/metabolismo , Células Acinares/metabolismo , Células Acinares/patología , Carcinoma in Situ/metabolismo , Carcinoma in Situ/patología , Inflamación/metabolismo , Hiperinsulinismo/complicaciones , Metaplasia/metabolismo , Metaplasia/patología , Obesidad/metabolismo , Insulinas/metabolismo
20.
J Proteome Res ; 11(4): 2609-18, 2012 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-22329400

RESUMEN

Our previous studies suggest that the α2,3sialylated T-antigen (NeuAcα2,3Galß1,3GalNac-) and associated glycan structures are likely to be elevated during cancer. An easy and reliable strategy to label mucinous glycans that contain such carbohydrates can enable the identification of novel glycoproteins that are cancer associated. To this end, the present study demonstrates that the exchange sialylation property of mammalian ST3Gal-II can facilitate the labeling of mucin glycoproteins in cancer cells, tumor specimens, and glycoproteins in cancer sera. Results show that (i) the radiolabeled mucin glycoproteins of each of the cancer cell lines studied (T47D, MCF7, LS180, LNCaP, SKOV3, HL60, DU4475, and HepG2) is distinct either in terms of the specific glycans presented or their relative distribution. While some cell lines like T47D had only one single sialylated O-glycan, others like LS180 and DU4475 contained a complex mixture of mucinous carbohydrates. (ii) [14C]sialyl labeling of primary tumor cells identified a 25-35 kDa mucin glycoprotein unique to pancreatic tumor. Labeled glycoproteins for other cancers had higher molecular weight. (iii) Studies of [14C] sialylated human sera showed larger mucin glycopeptides and >2-fold larger mucin-type chains in human serum compared to [14C]sialyl labeled glycans of fetuin. Overall, the exchange sialylation property of ST3Gal-II provides an efficient avenue to identify mucinous proteins for applications in glycoproteomics and cancer research.


Asunto(s)
Mucinas/química , Neoplasias/química , Neoplasias/metabolismo , Polisacáridos/química , Sialiltransferasas/metabolismo , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/química , Biomarcadores de Tumor/metabolismo , Isótopos de Carbono/química , Isótopos de Carbono/metabolismo , Línea Celular Tumoral , Electroforesis en Gel de Poliacrilamida , Femenino , Glicopéptidos/química , Glicopéptidos/metabolismo , Humanos , Masculino , Mucinas/sangre , Mucinas/metabolismo , Ácido N-Acetilneuramínico/química , Ácido N-Acetilneuramínico/metabolismo , Polisacáridos/análisis , Polisacáridos/metabolismo , beta-Galactosida alfa-2,3-Sialiltransferasa
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