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1.
J Immunol ; 206(1): 181-192, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33277387

RESUMEN

MCP-1-induced monocyte chemotaxis is a crucial event in inflammation and atherogenesis. Identifying the important signal transduction pathways that control monocyte chemotaxis can unravel potential targets for preventive therapies in inflammatory disease conditions. Previous studies have shown that the focal adhesion kinase Pyk2 plays a critical role in monocyte motility. In this study, we investigated the MCP-1-mediated activation of Pyk2 (particularly by the phosphorylation of Tyr402) in primary human peripheral blood monocytes. We showed that MCP-1 induces Src phosphorylation in a similar time frame and that the MCP-1-induced Pyk2 tyrosine phosphorylation is controlled by the Src family kinase. We also report, in this study, that PKCß, an isoform of PKC, is required for both Src and Pyk2 activation/phosphorylation in response to MCP-1 stimulation. We identified Lyn as the specific Src kinase isoform that is activated by MCP-1 and acts upstream of Pyk2 in primary monocytes. Furthermore, Lyn is found to be indispensable for monocyte migration in response to MCP-1 stimulation. Moreover, our coimmunoprecipitation studies in monocytes revealed that PKCß, Pyk2, and Lyn exist constitutively in a molecular complex. To our knowledge, our study has uncovered a novel PKCß-Lyn-Pyk2 signaling cascade in primary monocytes that regulates MCP-1-induced monocyte adhesion and migration.


Asunto(s)
Quimiocina CCL2/metabolismo , Quinasa 2 de Adhesión Focal/metabolismo , Monocitos/fisiología , Complejos Multiproteicos/metabolismo , Proteína Quinasa C beta/metabolismo , Familia-src Quinasas/metabolismo , Adhesión Celular , Células Cultivadas , Quimiocina CCL2/genética , Quimiotaxis , Humanos , Fosforilación , Cultivo Primario de Células , Proteínas Proto-Oncogénicas pp60(c-src)/metabolismo , Transducción de Señal
2.
Am J Physiol Renal Physiol ; 304(7): F1000-8, 2013 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-23389451

RESUMEN

Deoxycorticosterone salt (DOC-salt) hypertension-induced renal damage is enhanced in α-calcitonin gene-related peptide (α-CGRP) knockout (KO) compared with wild-type (WT) mice. However, since the α-CGRP KO mice have a 15-20 mmHg higher baseline mean arterial pressure (MAP) than WT mice, they also have a higher MAP than WT mice throughout the course of DOC-salt hypertension. To determine the mechanism by which the absence of α-CGRP enhances hypertension-induced renal damage, DOC-salt hypertension was induced in telemetry probe implanted α-CGRP KO and WT mice. To equalize the blood pressure (BP) to that of DOC-salt WT mice, an additional group of DOC-salt α-CGRP KO mice was given 0.025% hydralazine to drink. The DOC-salt protocol increased the final MAP in α-CGRP KO mice to 155 ± 6 mmHg and in WT mice to 140 ± 5 mmHg. The MAP of the hydralazine-treated DOC-salt α-CGRP KO mice was 139 ± 6 mmHg. Urinary excretion of microalbumin and isoprostane, a marker for oxidative stress, was increased, and creatinine clearance was decreased in DOC-salt α-CGRP KO compared with DOC-salt WT mice. Equalization of the MAP in DOC-salt α-CGRP KO to that of DOC-salt WT mice did not significantly improve these parameters. Renal macrophage infiltration; desmin, a marker of podocyte damage; and the inflammatory cytokines TNF-α and IFN-γ and the chemokines monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1α (MIP-1α) were increased in DOC-salt α-CGRP KO mice and were not reduced by hydralazine treatment. However, BP equalization did improve the renal histopathological damage, as determined by light microscopy. Therefore, in DOC-salt hypertension in mice, the mechanism(s) of the renal protective effects of α-CGRP are both BP independent and BP dependent.


Asunto(s)
Péptido Relacionado con Gen de Calcitonina/fisiología , Hipertensión/fisiopatología , Riñón/fisiología , Animales , Presión Arterial/efectos de los fármacos , Péptido Relacionado con Gen de Calcitonina/genética , Quimiocinas/metabolismo , Citocinas/metabolismo , Desmina/biosíntesis , Desoxicorticosterona , Hidralazina/farmacología , Hipertensión/inducido químicamente , Riñón/patología , Macrófagos/inmunología , Ratones , Ratones Noqueados
3.
J Lipid Res ; 54(2): 436-47, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23160182

RESUMEN

Monocyte chemoattractant protein-1 (MCP-1)-induced monocyte chemotaxis is a major event in inflammatory disease. Our prior studies have demonstrated that MCP-1-dependent chemotaxis requires release of arachidonic acid (AA) by activated cytosolic phospholipase A(2) (cPLA(2)). Here we investigated the involvement of AA metabolites in chemotaxis. Neither cyclooxygenase nor lipoxygenase pathways were required, whereas pharmacologic inhibitors of both the cytochrome-P450 (CYP) and the soluble epoxide hydrolase (sEH) pathways blocked monocyte chemotaxis to MCP-1. To verify specificity, we demonstrated that the CYP and sEH products epoxyeiscosatrienoic acids (EETs) and dihydroxyeicosatrienoic acids (DHETs), respectively, restored chemotaxis in the presence of the inhibitors, indicating that sEH-derived products are essential for MCP-1-driven chemotaxis. Importantly, DHETs also rescued chemotaxis in cPLA(2)-deficient monocytes and monocytes with blocked Erk1/2 activity, because Erk controls cPLA(2) activation. The in vitro findings regarding the involvement of CYP/sEH pathways were further validated in vivo using two complementary approaches measuring MCP-1-dependent chemotaxis in mice. These observations reveal the importance of sEH in MCP-1-regulated monocyte chemotaxis and may explain the observed therapeutic value of sEH inhibitors in treatment of inflammatory diseases, cardiovascular diseases, pain, and even carcinogenesis. Their effectiveness, often attributed to increasing EET levels, is probably influenced by the impairment of DHET formation and inhibition of chemotaxis.


Asunto(s)
Quimiocina CCL2/metabolismo , Quimiotaxis , Epóxido Hidrolasas/química , Epóxido Hidrolasas/metabolismo , Monocitos/citología , Animales , Ácido Araquidónico/biosíntesis , Quimiotaxis/efectos de los fármacos , Sistema Enzimático del Citocromo P-450/metabolismo , Inhibidores Enzimáticos/farmacología , Epóxido Hidrolasas/antagonistas & inhibidores , Ácidos Grasos Monoinsaturados/química , Ácidos Grasos Monoinsaturados/metabolismo , Femenino , Humanos , Lipooxigenasa/metabolismo , Ratones , Monocitos/efectos de los fármacos , Monocitos/enzimología , Monocitos/metabolismo , Fosfolipasas A2 Citosólicas/metabolismo , Prostaglandina-Endoperóxido Sintasas/metabolismo , Solubilidad
4.
J Lipid Res ; 54(1): 152-63, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23103474

RESUMEN

We examined the effects of three high-fat diets (HFD), differing in the percentage of total calories from saturated fat (SF) (6%, 12%, and 24%) but identical in total fat (40%), on body composition, macrophage behavior, inflammation, and metabolic dysfunction in mice. Diets were administered for 16 weeks. Body composition and metabolism [glucose, insulin, triglycerides, LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C), total cholesterol (TC)] were examined monthly. Adipose tissue (AT) expression of marker genes for M1 and M2 macrophages and inflammatory mediators [Toll-like receptor (TLR)-2, TLR-4, MCP-1, tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10, suppressor of cytokine signaling (SOCS)1, IFN-γ] was measured along with activation of nuclear factor kappa-B (NFκB), c-Jun N-terminal kinase (JNK), and p38- mitogen-activated protein kinase (MAPK). AT macrophage infiltration was examined using immunohistochemistry. Circulating MCP-1, IL-6, adiponectin, and leptin were also measured. SF content, independent of total fat, can profoundly affect adiposity, macrophage behavior, inflammation, and metabolic dysfunction. In general, the 12%-SF diet, most closely mimicking the standard American diet, led to the greatest adiposity, macrophage infiltration, and insulin resistance (IR), whereas the 6%-SF and 24%-SF diets produced lower levels of these variables, with the 24%-SF diet resulting in the least degree of IR and the highest TC/HDL-C ratio. Macrophage behavior, inflammation, and IR following HFD are heavily influenced by dietary SF content; however, these responses are not necessarily proportional to the SF percentage.


Asunto(s)
Adiposidad/efectos de los fármacos , Grasas de la Dieta/efectos adversos , Ácidos Grasos/efectos adversos , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Tejido Adiposo/citología , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/inmunología , Tejido Adiposo/metabolismo , Animales , Peso Corporal/efectos de los fármacos , Dieta Alta en Grasa/efectos adversos , Ingestión de Energía/efectos de los fármacos , Inflamación/sangre , Inflamación/etiología , Inflamación/metabolismo , Resistencia a la Insulina , Leptina/sangre , Macrófagos/inmunología , Masculino , Ratones
5.
Am J Physiol Gastrointest Liver Physiol ; 303(10): G1087-95, 2012 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-23019193

RESUMEN

Tumor-associated macrophages are associated with poor prognosis in certain cancers. Monocyte chemoattractant protein 1 (MCP-1) is thought to be the most important chemokine for recruitment of macrophages to the tumor microenvironment. However, its role on tumorigenesis in a genetic mouse model of colon cancer has not been explored. We examined the role of MCP-1 on tumor-associated macrophages, inflammation, and intestinal tumorigenesis. Male Apc(Min/+), Apc(Min/+)/MCP-1(-/-) or wild-type mice were euthanized at 18 wk of age and intestines were analyzed for polyp burden, apoptosis, proliferation, ß-catenin, macrophage number and phenotype, markers for cytotoxic T lymphocytes and regulatory T cells, and inflammatory mediators. MCP-1 deficiency decreased overall polyp number by 20% and specifically large polyp number by 45% (P < 0.05). This was consistent with an increase in apoptotic cells (P < 0.05), but there was no change detected in proliferation or ß-catenin. MCP-1 deficiency decreased F4/80-positive cells in both the polyp tissue and surrounding intestinal tissue (P < 0.05) as well as expression of markers associated with M1 (IL-12 and IL-23) and M2 macrophages (IL-13, CD206, TGF-ß, and CCL17) (P < 0.05). MCP-1 knockout was also associated with increased cytotoxic T lymphocytes and decreased regulatory T cells (P < 0.05). In addition, MCP-1(-/-) offset the increased mRNA expression of IL-1ß and IL-6 in intestinal tissue and IL-1ß and TNF-α in polyp tissue (P < 0.05), and prevented the decrease in SOCS1 expression (P < 0.05). We demonstrate that MCP-1 is an important mediator of tumor growth and immune regulation that may serve as an important biomarker and/or therapeutic target in colon cancer.


Asunto(s)
Quimiocina CCL2/fisiología , Neoplasias del Colon/fisiopatología , Inflamación/fisiopatología , Macrófagos/inmunología , Animales , Transformación Celular Neoplásica/patología , Quimiocina CCL2/deficiencia , Quimiocina CCL2/genética , Etiquetado Corte-Fin in Situ , Interleucina-12/biosíntesis , Interleucina-1beta/biosíntesis , Interleucina-23/biosíntesis , Interleucina-6/biosíntesis , Pólipos Intestinales/fisiopatología , Masculino , Ratones , Factor de Necrosis Tumoral alfa/biosíntesis
6.
Crit Ultrasound J ; 3(1): 1-12, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21516137

RESUMEN

A review of the development and implementation of a 4-year medical student integrated ultrasound curriculum is presented. Multiple teaching and assessment modalities are discussed as well as results from testing and student surveys. Lessons learned while establishing the curriculum are summarized. It is concluded that ultrasound is a well received, valuable teaching tool across all 4 years of medical school, and students learn ultrasound well, and they feel their ultrasound experience enhances their medical education.

7.
Cancer Res ; 70(10): 3896-904, 2010 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-20460521

RESUMEN

Lung cancer is the leading cause of cancer-related deaths with current chemotherapies lacking adequate specificity and efficacy. Beta-lapachone (beta-lap) is a novel anticancer drug that is bioactivated by NAD(P)H:quinone oxidoreductase 1, an enzyme found specifically overexpressed in non-small cell lung cancer (NSCLC). Herein, we report a nanotherapeutic strategy that targets NSCLC tumors in two ways: (a) pharmacodynamically through the use of a bioactivatable agent, beta-lap, and (b) pharmacokinetically by using a biocompatible nanocarrier, polymeric micelles, to achieve drug stability, bioavailability, and targeted delivery. Beta-lap micelles produced by a film sonication technique were small ( approximately 30 nm), displayed core-shell architecture, and possessed favorable release kinetics. Pharmacokinetic analyses in mice bearing subcutaneous A549 lung tumors showed prolonged blood circulation (t(1/2), approximately 28 h) and increased accumulation in tumors. Antitumor efficacy analyses in mice bearing subcutaneous A549 lung tumors and orthotopic Lewis lung carcinoma models showed significant tumor growth delay and increased survival. In summary, we have established a clinically viable beta-lap nanomedicine platform with enhanced safety, pharmacokinetics, and antitumor efficacy for the specific treatment of NSCLC tumors.


Asunto(s)
Portadores de Fármacos/química , Neoplasias Pulmonares/tratamiento farmacológico , NAD(P)H Deshidrogenasa (Quinona)/antagonistas & inhibidores , Nanomedicina , Naftoquinonas/farmacología , Animales , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Femenino , Humanos , Neoplasias Pulmonares/patología , Ratones , Ratones Desnudos , Micelas , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , Naftoquinonas/farmacocinética , Tasa de Supervivencia , Distribución Tisular , Ensayos Antitumor por Modelo de Xenoinjerto
8.
J Exp Med ; 205(2): 347-59, 2008 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-18208975

RESUMEN

Monocyte chemoattractant protein-1 (MCP-1) directs migration of blood monocytes to inflamed tissues. Despite the central role of chemotaxis in immune responses, the regulation of chemotaxis by signal transduction pathways and their in vivo significance remain to be thoroughly deciphered. In this study, we examined the intracellular location and functions of two recently identified regulators of chemotaxis, Ca(2+)-independent phospholipase (iPLA(2)beta) and cytosolic phospholipase (cPLA(2)alpha), and substantiate their in vivo importance. These enzymes are cytoplasmic in unstimulated monocytes. Upon MCP-1 stimulation, iPLA(2)beta is recruited to the membrane-enriched pseudopod. In contrast, cPLA(2)alpha is recruited to the endoplasmic reticulum. Although iPLA(2)beta or cPLA(2)alpha antisense oligodeoxyribonucleotide (ODN)-treated monocytes display reduced speed, iPLA(2)beta also regulates directionality and actin polymerization. iPLA(2)beta or cPLA(2)alpha antisense ODN-treated adoptively transferred mouse monocytes display a profound defect in migration to the peritoneum in vivo. These converging observations reveal that iPLA(2)beta and cPLA(2)alpha regulate monocyte migration from different intracellular locations, with iPLA(2)beta acting as a critical regulator of the cellular compass, and identify them as potential targets for antiinflammatory strategies.


Asunto(s)
Quimiocina CCL2/inmunología , Fosfolipasas A2 Grupo IV/inmunología , Fosfolipasas A2 Grupo VI/inmunología , Monocitos/inmunología , Actinas/metabolismo , Traslado Adoptivo , Animales , Ácidos Araquidónicos/farmacología , Células Cultivadas , Quimiotaxis/efectos de los fármacos , Quimiotaxis/inmunología , Femenino , Fosfolipasas A2 Grupo IV/antagonistas & inhibidores , Fosfolipasas A2 Grupo VI/antagonistas & inhibidores , Humanos , Leucocitos Mononucleares/inmunología , Ratones , Ratones Endogámicos BALB C , Monocitos/efectos de los fármacos , Naftalenos/farmacología , Oligodesoxirribonucleótidos Antisentido/farmacología , Peritonitis/inducido químicamente , Peritonitis/inmunología , Pironas/farmacología
9.
Ann Plast Surg ; 57(4): 422-30, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16998336

RESUMEN

Bilateral vascularized bone marrow transplant (VBMT) model was designed to induce chimerism across the major histocompatibility (MHC) barrier under combined alphabeta T-cell receptor monoclonal antibody and cyclosporine A (alphabeta-TCRmAb/CsA) protocol. Seventeen transplants were performed between BN(RT1) donors and Lewis(RTI) recipients. Group I, isograft controls; Group II, allografts rejection controls; Group III, allografts under 7-day protocol of alphabeta-TCRmAb/CsA. Donor bilateral femoral bones were bilaterally anastomosed to the abdominal aorta and inferior vena cava of recipient. At day 7 posttransplantation, all bone flaps were viable. Groups I and III survived without signs of rejection. In Group III, peak level of chimerism in peripheral blood was evaluated at day 21 (24.2%), at day 63 declined to 1.5%, and was maintained at this level thereafter. Donor-derived cells were present in the bone marrow of recipients at 28.2% at day 21 posttransplant. Histology confirmed viability of bone marrow cells in isograft during the entire follow-up and up to 35 days in treatment Group III. Bilateral VBMT induced donor-specific chimerism across the MHC barrier under the immunomodulatory protocol of alphabeta-TCRmAb/CsA.


Asunto(s)
Trasplante de Médula Ósea/métodos , Complejo Mayor de Histocompatibilidad/inmunología , Quimera por Trasplante/inmunología , Animales , Anticuerpos Monoclonales/farmacología , Ciclosporina/farmacología , Fémur , Citometría de Flujo , Supervivencia de Injerto/inmunología , Inmunosupresores/farmacología , Ratas , Ratas Endogámicas BN , Ratas Endogámicas Lew
10.
Ann Plast Surg ; 56(6): 658-64, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16721081

RESUMEN

We present a new model of vascularized bone marrow transplantation-bilateral vascularized femoral bone (BVFB) isograft transplant based on abdominal aorta and inferior vena cava. A total of 7 BVFB isograft transplants were performed between Lewis (RT1) rats. In the donor, both femoral bones were harvested based on the abdominal aorta and inferior vena cava. In the recipient, the harvested isograft transplants were transferred into the inguinal region (in 3 animals) and into the abdominal cavity (in 4 animals). The mean operation time was 3 hours and 35 minutes. The mean warm ischemic time was 35 minutes. The vascular pedicles of the transplants that were transferred into the inguinal region were thrombosed at day 7 posttransplantation. The vascular pedicles of transplants into the abdominal cavity were patent and the bones were viable during the follow-up period of 63 days posttransplant. We have confirmed the feasibility of BVFB transplantation based on abdominal aorta and inferior vena cava.


Asunto(s)
Trasplante de Médula Ósea/métodos , Fémur/cirugía , Modelos Animales , Anastomosis Quirúrgica , Animales , Aorta Abdominal , Estudios de Factibilidad , Masculino , Ratas , Ratas Endogámicas Lew , Recolección de Tejidos y Órganos , Trasplante Homólogo , Vena Cava Inferior
11.
J Biol Chem ; 278(42): 40788-92, 2003 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-12912997

RESUMEN

Phagocyte NADPH oxidase is critical for defense against pathogens and contributes to inflammatory tissue injury. One component of the NADPH oxidase complex is the small GTP-binding protein Rac. There are two isoforms of Rac, and Rac2 is the predominant isoform in neutrophils and has been shown to be essential for NADPH oxidase activity. In primary human monocytes we report that in contrast to neutrophils, Rac1 is the predominantly expressed isoform. Upon monocyte activation by a variety of agents, we found that Rac1 dissociates from Rho GDP dissociation inhibitor (RhoGDI) and translocates to the membrane. We also found that Rac1 interacts with two other NADPH oxidase components, p67phox and p47phox, upon monocyte activation. These data indicate that Rac1, and not Rac2, is a component of the activated NADPH oxidase in monocytes. This finding suggests that it may be possible to selectively interfere with either monocyte or neutrophil NADPH oxidase activity, thereby selectively targeting chronic versus acute inflammatory processes.


Asunto(s)
Monocitos/metabolismo , NADPH Oxidasas/química , Proteínas de Unión al GTP rac/metabolismo , Proteína de Unión al GTP rac1/metabolismo , Western Blotting , Membrana Celular/metabolismo , Citosol/metabolismo , Relación Dosis-Respuesta a Droga , Humanos , Inflamación , NADPH Oxidasas/metabolismo , Neutrófilos/metabolismo , Fosfoproteínas/metabolismo , Pruebas de Precipitina , Isoformas de Proteínas , Transporte de Proteínas , ARN Mensajero/metabolismo , Proteínas Recombinantes/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteína RCA2 de Unión a GTP
12.
J Biol Chem ; 278(28): 25317-22, 2003 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-12724308

RESUMEN

Monocyte chemoattractant protein 1 (MCP-1) is important in attracting monocytes to sites of inflammation. Using predominantly pharmacological approaches, prior studies have indicated that serine/threonine kinases are involved in the MCP-1-induced signaling pathways. We report here that there is substantial inhibition of MCP-1-stimulated chemotaxis of human monocytes treated with inhibitors selective for the subset of serine/threonine kinases, protein kinase C (PKC). Selective inhibitors of PKC such as GF109203X and Calphostin C both caused approximately 80% inhibition of chemotaxis. Because these pharmacological inhibitors do not specifically inhibit individual PKC isoforms, we chose to use antisense oligodeoxyribonucleotides (ODN) to specifically reduce PKC isoform expression, first by inhibiting expression of the conventional PKC family, and next by using specific antisense ODN for PKCalpha and PKCbeta. Conventional PKC-antisense ODN treatment completely and significantly inhibited monocyte chemotaxis to MCP-1, whereas sense-control ODN caused no significant inhibition. PKCbeta-antisense ODN caused 89.2% inhibition of chemotaxis at its highest dose. In contrast, PKCbeta-sense ODN and PKCalpha-antisense and -sense ODN were without effect. Further studies evaluating the calcium response that is triggered upon MCP-1 interaction with its receptor, CCR2, indicate that this response is not altered by antisense or sense ODN treatment, thus supporting our hypothesis that PKCbeta is critical for post-receptor signal transduction downstream of the immediate calcium signal. These data contribute to our developing understanding of the signal transduction pathways involved in the chemotactic response of human monocytes to MCP-1 and uniquely identify the requirement for the PKCbeta isoform in this important process.


Asunto(s)
Quimiocina CCL2/metabolismo , Monocitos/metabolismo , Proteína Quinasa C/fisiología , Western Blotting , Calcio/metabolismo , Células Cultivadas , Quimiotaxis/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Humanos , Indoles/farmacología , Maleimidas/farmacología , Naftalenos/farmacología , Oligonucleótidos/química , Oligonucleótidos Antisentido/metabolismo , Oligonucleótidos Antisentido/farmacología , Isoformas de Proteínas , Proteína Quinasa C/metabolismo , Proteína Quinasa C beta , Proteína Quinasa C-alfa , ARN Mensajero/metabolismo , Factores de Tiempo , Rayos Ultravioleta
13.
J Natl Cancer Inst ; 94(13): 1010-9, 2002 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-12096086

RESUMEN

BACKGROUND: The ubiquitous plasma membrane transcobalamin II receptor (TC II-R) mediates uptake of cobalamin (Cbl; vitamin B12), an essential micronutrient. Tumors often require more Cbl than normal tissue, and increased Cbl uptake may result from increased TC II-R expression. To examine whether Cbl could therefore be used as a carrier molecule to target a chemotherapy drug, we tested an analogue of Cbl with nitric oxide as a ligand, nitrosylcobalamin (NO-Cbl). Because interferon beta (IFN-beta) has antitumor effects and increases expression of some membrane receptors, we examined whether it may enhance the effects of NO-Cbl. METHODS: Antiproliferative effects of NO-Cbl were assessed in 24 normal and cancer cell lines. Xenograft tumors of human ovarian cancer NIH-OVCAR-3 cells were established in athymic nude mice, and tumor growth was monitored after treatment with NO-Cbl and IFN-beta, both individually and concomitantly. TC II-R expression and apoptosis was monitored in vitro and in vivo. RNA protection assays and mitochondrial membrane potential assays were used to distinguish the extrinsic and intrinsic apoptotic pathways, respectively. RESULTS: Cancer cell lines were more sensitive to NO-Cbl (with ID(50)s [the dose that inhibits growth by 50%] as low as 2 microM) than normal cell lines (with ID(50)s of 85-135 microM). Single-agent NO-Cbl and IFN-beta treatment of NIH-OVCAR-3 xenografts induced tumor regression, whereas combination treatment induced tumor eradication. IFN-beta treatment increased TC II-R expression in vitro and uptake of [(57)Co]cobalamin in vivo. Compared with NIH-OVCAR-3 cells treated with NO-Cbl, cells treated with NO-Cbl and IFN-beta were more apoptotic and expressed higher mRNA levels of various apoptosis-associated genes. No changes in mitochondrial membrane potential were observed in cells treated with NO-Cbl. CONCLUSION: NO-Cbl inhibited tumor growth in vivo by activating the extrinsic apoptotic pathway. The increased expression of TC II-R induced by IFN-beta resulted in enhanced antitumor effects with NO-Cbl both in vitro and in vivo.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias de la Mama/terapia , Interferón beta/uso terapéutico , Melanoma/terapia , Compuestos Nitrosos/farmacología , Neoplasias Ováricas/terapia , Receptores de Superficie Celular/metabolismo , Vitamina B 12/análogos & derivados , Vitamina B 12/farmacología , Animales , Anexina A5/metabolismo , Antineoplásicos/uso terapéutico , Apoptosis/fisiología , Western Blotting , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Caspasa 8 , Caspasa 9 , Caspasas/metabolismo , División Celular/efectos de los fármacos , Terapia Combinada , Sinergismo Farmacológico , Femenino , Humanos , Técnicas para Inmunoenzimas , Masculino , Melanoma/metabolismo , Melanoma/patología , Potenciales de la Membrana , Ratones , Ratones Desnudos , Mitocondrias/metabolismo , Óxido Nítrico/metabolismo , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Rodaminas , Ribonucleasa Pancreática/metabolismo , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/metabolismo
14.
Blood ; 99(12): 4434-42, 2002 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-12036873

RESUMEN

The capacity of an adenovirus encoding the mature form of vascular endothelial growth factor (VEGF)-D, VEGF-D Delta N Delta C, to induce angiogenesis, lymphangiogenesis, or both was analyzed in 2 distinct in vivo models. We first demonstrated in vitro that VEGF-D Delta N Delta C encoded by the adenovirus (Ad-VEGF-D Delta N Delta C) is capable of inducing endothelial cell proliferation and migration and that the latter response is primarily mediated by VEGF receptor-2 (VEGFR-2). Second, we characterized a new in vivo model for assessing experimental angiogenesis, the rat cremaster muscle, which permits live videomicroscopy and quantitation of functional blood vessels. In this model, a proangiogenic effect of Ad-VEGF-D Delta N Delta C was evident as early as 5 days after injection. Immunohistochemical analysis of the cremaster muscle demonstrated that neovascularization induced by Ad-VEGF-D Delta N Delta C and by Ad-VEGF-A(165) (an adenovirus encoding the 165 isoform of VEGF-A) was composed primarily of laminin and VEGFR-2-positive vessels containing red blood cells, thus indicating a predominantly angiogenic response. In a skin model, Ad-VEGF-D Delta N Delta C induced angiogenesis and lymphangiogenesis, as indicated by staining with laminin, VEGFR-2, and VEGFR-3, whereas Ad-VEGF-A(165) stimulated the selective growth of blood vessels. These data suggest that the biologic effects of VEGF-D are tissue-specific and dependent on the abundance of blood vessels and lymphatics expressing the receptors for VEGF-D in a given tissue. The capacity of Ad-VEGF-D Delta N Delta C to induce endothelial cell proliferation, angiogenesis, and lymphangiogenesis demonstrates that its potential usefulness for the treatment of coronary artery disease, cerebral ischemia, peripheral vascular disease, restenosis, and tissue edema should be tested in preclinical models.


Asunto(s)
Adenoviridae/genética , Factores de Crecimiento Endotelial/farmacología , Neovascularización Fisiológica/efectos de los fármacos , Transducción Genética , Animales , Factores de Crecimiento Endotelial/genética , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Inmunohistoquímica , Laminina/análisis , Masculino , Microscopía por Video , Modelos Animales , Músculo Esquelético/irrigación sanguínea , Músculo Esquelético/química , Músculo Esquelético/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Proteínas Tirosina Quinasas Receptoras/análisis , Receptores de Factores de Crecimiento/análisis , Receptores de Factores de Crecimiento Endotelial Vascular , Piel/irrigación sanguínea , Piel/química , Piel/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular , Factor D de Crecimiento Endotelial Vascular , Receptor 3 de Factores de Crecimiento Endotelial Vascular
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