RESUMEN
BACKGROUND: It is important to collect data about the risk of transformation of an actinic keratosis (AK) lesion into squamous cell carcinoma (SCC) after a single photodynamic therapy (PDT) with 5-ALA patch for a longer follow-up period under daily routine. QUESTIONS ADDRESSED: The purpose of this non-interventional study (NIS) was to collect data on the frequency of occurrence of SCCs in the treated area during an interval of 2 years after a single 5-ALA patch-PDT. EXPERIMENTAL DESIGN: This prospective observational case-only study included patients with mild AK lesions on the head and face treated with 5-ALA patch-PDT according to the Summary of Product Characteristics (SPC). RESULTS: In 370 patients, the risk of transformation of their treated AK lesion into SCC was 0.073% with its exact 95% confidence interval using the Poisson distribution of [0.009%, 0.262%]. The rate of complete clinical clearance on lesion basis after 3 months was 84.3%. CONCLUSION: The efficacy and the safety results show no observation of an increased risk for conversion of an AK into a SCC 2 years after a single 5-ALA patch-PDT. Additionally, the high clinical complete remission rate under routine conditions is comparable to the rates observed in the approval trials.
Asunto(s)
Ácido Aminolevulínico/administración & dosificación , Carcinoma de Células Escamosas/prevención & control , Queratosis Actínica/tratamiento farmacológico , Fotoquimioterapia , Ácido Aminolevulínico/efectos adversos , Daño del ADN , Progresión de la Enfermedad , Humanos , Estrés Oxidativo , Fotoquimioterapia/efectos adversos , Lesiones Precancerosas/tratamiento farmacológico , Estudios Prospectivos , RiesgoRESUMEN
Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors that function mainly in the regulation of glucose and lipid homeostasis. PPAR agonists have been shown to control inflammation by inhibition of distinct proinflammatory genes. Aberrant activation of the epidermal growth factor receptor and/or overexpression of its ligand, transforming growth factor-α (TGFα), are key features of both neoplastic and inflammatory hyperproliferative epithelia. Matrix metalloproteinase 9 (MMP9) belongs to the set of genes that are effectively induced by TGFα in keratinocytes. Induction of MMP9 expression is strongly linked to regenerative skin repair mechanisms, inflammatory skin diseases and tumor metastasis. We explored whether the known anti-inflammatory effects of PPARδ ligands involve inhibiting the TGFα-mediated upregulation of MMP9. The PPARδ agonists potently inhibited TGFα-induced MMP9 expression in human keratinocytes. This inhibition was observed at both the protein and mRNA levels. Transcriptional activation studies with deletion constructs of a reporter gene revealed that PPARδ agonists mediate their inhibitory effects via an AP1-binding site. Electromobility shift assay analysis indicated that MMP9 gene expression is inhibited by repressing site-dependent DNA binding and transactivation by c-fos. In conclusion, our data provide the first evidence that MMP9 expression induced by TGFα is a valid target of PPARδ ligands in keratinocytes.
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Regulación de la Expresión Génica/fisiología , Queratinocitos/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , PPAR delta/agonistas , Factor de Transcripción AP-1/metabolismo , Factor de Crecimiento Transformador alfa/farmacología , Sitios de Unión/genética , Línea Celular , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Células Cultivadas , Ensayo de Cambio de Movilidad Electroforética , Expresión Génica/efectos de los fármacos , Expresión Génica/genética , Humanos , Queratinocitos/efectos de los fármacos , Masculino , Metaloproteinasa 9 de la Matriz/genética , Fenoxiacetatos/farmacología , Regiones Promotoras Genéticas/genética , Proteínas Proto-Oncogénicas c-fos/metabolismo , Proteínas Proto-Oncogénicas c-jun/metabolismo , Tiazoles/farmacología , Regulación hacia Arriba/genéticaRESUMEN
The association between angiogenesis and chronic inflammatory diseases, such as psoriasis, seems to be an important phenomenon implicated in the pathogenesis of these medical conditions. Recent studies provide evidence that dimethylfumarate (DMF) has a profound anti-inflammatory as well as anti-tumorigenic action, although the effect of DMF on angiogenesis is unknown. Signaling via the vascular endothelial growth factor receptor-2 (VEGFR2) pathway is critical for angiogenic responses. Therefore, we explored whether the known anti-inflammatory and anti-tumorigenic properties of DMF might be mediated in part by anti-angiogenic effects through the reduction in VEGFR2 expression. In this study, DMF was found to inhibit endothelial VEGFR2 expression; time- and concentration-dependent inhibition was demonstrated both at the level of protein and mRNA expression. This blockade was coincident with the inhibition of the formation of capillary-like structures. The DMF-dependent inhibition of VEGFR2 transcription was found to be mediated by an element located between base pairs -60 and -37, which contains two adjacent, consensus Sp1 transcription factor-binding sites, and the constitutive formation of complexes containing Sp1 at this site is decreased by DMF treatment. Inhibition of VEGFR-2 is shown to be one critical aspect in DMF-mediated anti-angiogenic effects.
Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Células Endoteliales/efectos de los fármacos , Fumaratos/farmacología , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Células Cultivadas , Dimetilfumarato , Células Endoteliales/metabolismo , Humanos , Regiones Promotoras Genéticas , ARN Mensajero/análisis , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genéticaRESUMEN
Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors that are implicated in the regulation of lipid and glucose homeostasis. PPAR agonists have been shown to control inflammatory processes, in part by inhibiting distinct proinflammatory genes (e.g. Il-1ß and IFN-γ). IL-8 is a member of the proinflammatory chemokine family that is important for various functions, such as mediating the adhesion of eosinophilic granulocytes onto endothelial cells. The influence of PPARδ activators on the expression of IL-8 in noninduced quiescent endothelial cells is unclear. Therefore, we explored the influence of PPARδ activators on the expression of IL-8 in nonstimulated endothelial cells. PPARδ agonists induce IL-8 expression in human umbilical vein endothelial cells. This induction is demonstrated at the level of both protein and mRNA expression. Transcriptional activation studies using IL-8 reporter gene constructs and DNA binding assays revealed that PPARδ agonists mediated their effects via an NFκB binding site. It is well known that IL-8 is also regulated by mRNA stability. To provide further evidence for this concept, we performed mRNA stability assays and found that PPARδ agonists induce the mRNA stability of IL-8. In addition, we showed that PPARδ agonists induce the phosphorylation of ERK1/2 and p38, which are known to be involved in the increase of mRNA stability. The inhibition of these MAPK signaling pathways resulted in a significant suppression of the induced IL-8 expression and the reduced mRNA stability. Therefore, our data provide the first evidence that PPARδ induces IL-8 expression in nonstimulated endothelial cells via transcriptional as well as posttranscriptional mechanisms.
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Células Endoteliales/citología , Regulación de la Expresión Génica , Interleucina-8/metabolismo , PPAR delta/metabolismo , Procesamiento Postranscripcional del ARN , Transcripción Genética , Quimiocinas/metabolismo , Endotelio Vascular/citología , Regulación Neoplásica de la Expresión Génica , Humanos , Inflamación , Interleucina-1beta/metabolismo , Fosforilación , Transducción de Señal , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Murine γ/δ T cells express canonical Vγ5Vδ1 chains in the epidermis and Vγ6Vδ1 chains at reproductive sites. Both subsets carry an identical Vδ1-Dδ2-Jδ2 chain which completely lacks junctional diversity. These cells are thought to monitor tissue integrity via recognition of stress-induced self antigens. In this study, we showed by reverse transcription-polymerase chain reaction (RT-PCR), complementarity determining region 3 (CDR3) spectratyping and sequencing of the junctional regions of Vδ1 chains from C57BL/6 mice (aged 1 day to 14 months) that the canonical Vδ1-Dδ2-Jδ2 chain is also consistently present at other sites such as the thymus, gut, lung, liver, spleen and peripheral blood. In addition, we found multiple Vδ1 chains with fetal type rearrangements which were also shared among organs and among animals. These Vδ1 chains were typically characterized by a conserved amino acid motif, 'GGIRA'. Furthermore, by analysing the early postnatal period at days 10 and 16, we demonstrated that the diversification of the thymic Vδ1 repertoire is not paralleled by a diversification of extrathymic Vδ1+γ/δ T cells. This indicates that only fetal type rearrangements survive at extrathymic sites. In conclusion, γ/δ T cells expressing the canonical Vδ1-Dδ2-Jδ2 chain are not unique to the skin and reproductive sites. Furthermore, we found other γ/δ T cells expressing fetal type Vδ1 chains which were shared among different organs and animals. Thus, γ/δ T cells expressing conserved Vδ1 chains are likely to have important functions. We suggest a model in which this subset continuously recirculates throughout the organism and rapidly responds to stress-induced self antigens.
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Reordenamiento Génico de la Cadena delta de los Receptores de Antígenos de los Linfocitos T/inmunología , Sistema Inmunológico/inmunología , Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Envejecimiento/genética , Envejecimiento/inmunología , Secuencias de Aminoácidos/genética , Secuencias de Aminoácidos/inmunología , Secuencia de Aminoácidos/genética , Animales , Animales Recién Nacidos , Secuencia de Bases/genética , Clonación Molecular , Regiones Determinantes de Complementariedad/genética , Feto/inmunología , Expresión Génica/genética , Expresión Génica/inmunología , Reordenamiento Génico de la Cadena delta de los Receptores de Antígenos de los Linfocitos T/genética , Sistema Inmunológico/citología , Sistema Inmunológico/crecimiento & desarrollo , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Receptores de Antígenos de Linfocitos T gamma-delta/genética , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Piel/inmunología , Piel/metabolismo , Timo/inmunología , Timo/metabolismoRESUMEN
Leukocyte extravasation is a prerequisite for host defense and autoimmunity alike. Detailed understanding of the tightly controlled and overlapping sequences of leukocyte extravasation might aid development of novel therapeutic strategies. Leukocyte extravasation is initiated by interaction of selectins with appropriate carbohydrate ligands. Lack of P-selectin expression leads to decreased contact hypersensitivity responses. Yet, it remains unclear if this is due to inhibition of leukocyte extravasation to the skin or due to interference with initial immune activation in lymph nodes. In line with previous data, we here report a decreased contact hypersensitivity response, induced by 2,4,-dinitrofluorobenzene (DNFB), in P-selectin-deficient mice. Eliciting an immune reaction towards DNFB in wild-type mice, followed by adoptive transfer to P-selectin-deficient mice, had no impact on inflammatory response in recipients. This was significantly reduced in wild-type recipient mice adoptively transferred with DNFB immunity generated in P-selectin-deficient mice. To investigate if platelet or endothelial P-selectin was involved, mice solely lacking platelet P-selectin expression generated by bone marrow transplantation were used. Adoptive transfer of immunity from wild-type mice reconstituted with P-selectin-deficient bone marrow led to a decrease of inflammatory response. Comparing this decrease to the one observed using P-selectin-deficient mice, no differences were observed. Our observations indicate that platelet, not endothelial, P-selectin contributes to generation of immunity in DNFB-induced contact hypersensitivity.
Asunto(s)
Plaquetas/metabolismo , Dermatitis por Contacto/inmunología , Dermatitis por Contacto/patología , Células Endoteliales/metabolismo , Inmunidad/inmunología , Selectina-P/metabolismo , Piel/patología , Traslado Adoptivo , Animales , Forma de la Célula , Dermatitis por Contacto/complicaciones , Dinitrofluorobenceno , Inflamación/complicaciones , Inflamación/inmunología , Inflamación/patología , Ratones , Ratones Endogámicos C57BL , Piel/inmunologíaRESUMEN
Infiltration of bone marrow derived cells is part of the angiogenic switch required for uncontrolled tumour growth. However, the nature of the tumour-infiltrating cells from bone marrow has not been fully elucidated. To investigate the phenotype of bone marrow derived cells within a tumour, we employed the Lewis lung carcinoma (LLC) murine tumour model. We followed bone marrow derivation of tumour-infiltrating cells through transplantation of CD45.2 bone marrow cells into pre-irradiated CD45.1 mice. We found robust CD45.2 donor type chimerism in bone marrow and blood of CD45.1 recipient tumour-bearing mice. Flow cytometric analysis of LLC tumours showed, in addition to previously described pro-angiogenic CD45(+)VEGFR2(+)'endothelial progenitor cells' (EPC), or CD45(+)Tie2(+)'Tie2-expressing monocytes' (TEM), incorporation of donor type lineage marker negative (Lin(-)) and Lin(-)Sca1(+) undifferentiated haematopoietic cell types. Immunohistochemical analysis confirmed the extravasal location of the primitive haematopoietic cells. Flow-cytometric sorting of bone marrow cells and subsequent analysis in haematopoietic colony-forming assays revealed that cells with a Lin(-)Sca1(+) phenotype, which were initially negative for VEGFR2 and Tie2, gave rise to VEGFR2(+) and/or Tie2(+) cells. Moreover, Lin(-) bone marrow cells pre-labelled with the membrane dye PKH26 (a red fluorochrome) and transplanted i.v. into tumour-bearing mice were found to extravasate and incorporate into LLC tumours within 24 hrs. Thus, primitive haematopoietic precursors which are thought to be precursors of EPC and TEMs, constitute a part of the tumour microenvironment. This makes them an attractive target cell population for tumour-directed cellular therapies.
Asunto(s)
Células de la Médula Ósea/citología , Animales , Hematopoyesis , Ratones , FenotipoRESUMEN
RhoA, Rac1 and CDC42 are small GTP-binding proteins of the Rho family that play a crucial role in regulation of the actin-based cytoskeleton. In addition to cell growth regulation, they are implicated in transcriptional activation, oncogenic transformation and angiogenesis. The small Rho-GTPases have been linked to vascular endothelial growth factor (VEGF)-induced signalling pathways, but their role has not yet been elucidated. As signalling via the VEGF receptor-2 (VEGFR2) pathway is critical for angiogenic responses in cancer, wound repair and ischaemic and inflammatory diseases, we investigated whether the small Rho-GTPase Rac1 influences VEGFR2 expression in human endothelial cells. In this study, we show that a dominant negative Rac1 expression vector led to a pronounced decrease in VEGFR2 mRNA and protein expression. To identify minimal promoter requirements and potential applications of the small Rho-GTPases, we used VEGFR2 promoter-reporter gene constructs containing various deletions. The inhibitory effects of dominant negative Rac1 on the transcriptional activity of the VEGFR2 promoter localized to an element between -77 and -60 that contains an Sp1 transcription factor binding site. Electrophoretic mobility shift assays demonstrated that constitutive Sp1-dependent DNA binding decreased with Rac1 inhibition. Hence, repression of the small Rho GTPase Rac1 seems to be an additional critical molecular mechanism in the regulation of VEGFR2 expression.
Asunto(s)
ADN/metabolismo , Células Endoteliales/metabolismo , Factor de Transcripción Sp1/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Proteína de Unión al GTP rac1/metabolismo , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/farmacología , Sitios de Unión/genética , Células Cultivadas , ADN/genética , Ensayo de Cambio de Movilidad Electroforética , Expresión Génica/genética , Humanos , Regiones Promotoras Genéticas/genética , Unión Proteica/efectos de los fármacos , Unión Proteica/genética , ARN Interferente Pequeño/genética , Factor de Transcripción Sp1/inmunología , Transfección , Receptor 1 de Factores de Crecimiento Endotelial Vascular/metabolismo , Proteína de Unión al GTP rac1/genéticaRESUMEN
PURPOSE: This phase III, randomized, double-blind, placebo-controlled study was conducted to evaluate the efficacy and safety of sorafenib with carboplatin and paclitaxel (CP) in patients with advanced melanoma who had progressed on a dacarbazine- or temozolomide-containing regimen. PATIENTS AND METHODS: A total of 270 patients were randomly assigned to receive intravenous paclitaxel 225 mg/m2 plus intravenous carboplatin at area under curve 6 (AUC 6) on day 1 of a 21-day cycle followed by either placebo (n = 135) or oral sorafenib 400 mg (n = 135) twice daily on days 2 to 19. The primary efficacy end point was progression-free survival (PFS); secondary and tertiary end points included overall survival and incidence of best response, respectively. RESULTS: The median PFS was 17.9 weeks for the placebo plus CP arm and 17.4 weeks for the sorafenib plus CP arm (hazard ratio, 0.91; 99% CI, 0.63 to 1.31; two-sided log-rank test P = .49). Response rate was 11% with placebo versus 12% with sorafenib. Dermatologic events, grade 3 thrombocytopenia, diarrhea, and fatigue were more common in patients treated with sorafenib plus CP versus placebo plus CP. CONCLUSION: In this study, the addition of sorafenib to CP did not improve any of the end points over placebo plus CP and cannot be recommended in the second-line setting for patients with advanced melanoma. Both regimens had clinically acceptable toxicity profiles with no unexpected adverse events. A trial of similar design for the first-line treatment of patients with advanced melanoma (intergroup trial E2603) is currently ongoing.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Melanoma/tratamiento farmacológico , Estadificación de Neoplasias , Adulto , Anciano , Anciano de 80 o más Años , Carboplatino/uso terapéutico , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Paclitaxel/uso terapéutico , Placebos , Resultado del Tratamiento , Adulto JovenRESUMEN
The ubiquitin-proteasome system is the major pathway for intracellular protein degradation in eukaryotic cells. This system controls a wide range of cellular regulatory proteins, including transcription factors and cell cycle regulatory proteins. Recent evidence also established the importance of the proteasome in tumor development, showing antitumor and antiangiogenic actions by using selective inhibitors in vivo. As signaling via the vascular endothelial growth factor receptor 2 (VEGFR2) pathway is critical for angiogenic responses to occur, we explored whether antiangiogenic effects due to proteasome inhibition were partly mediated through decreased endothelial VEGFR2 expression. This study shows that different proteasome inhibitors blocked VEGFR2 expression in a time-dependent and concentration-dependent manner. This blockade was paralleled by the respective inhibition of the formation of capillary-like structures and endothelial cell migration. In contrast, neither tie-2 nor VEGFR1 expression was significantly affected by proteasome inhibitor treatment. The suppressive effects on VEGFR2 expression were not conveyed by increased shedding or a decrease in protein half-life, suggesting that transcriptional mechanisms accounted for the observed effects. In line with this conclusion, proteasome inhibition significantly suppressed VEGFR2 mRNA accumulation. In addition, inhibitor treatment considerably decreased the transcriptional activity of 5' deletional VEGFR2 promoter gene constructs. Proteasome inhibition-mediated repression was controlled by a GC-rich region that harbored one consensus Sp1-binding site. Subsequent EMSA analyses showed decreased constitutive Sp1-dependent DNA binding in response to proteasome inhibition. In addition, we could show that proteasome inhibitors reduced VEGFR2 mRNA stability. Therefore, VEGFR2 expression may constitute a critical molecular target of proteasome inhibitors that may mediate their antiangiogenic effects in vivo.
Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Células Endoteliales/efectos de los fármacos , Inhibidores de Proteasas/farmacología , Inhibidores de Proteasoma , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Sitios de Unión , Células Cultivadas , Regulación hacia Abajo , Células Endoteliales/fisiología , Humanos , Regiones Promotoras Genéticas , ARN Mensajero/análisis , Factor de Transcripción Sp1/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genéticaRESUMEN
Cytoskeletal polymers control a wide range of cellular functions, including proliferation, migration, and gene expression. As changes in endothelial cell shape and motility are required to form vascular networks, we hypothesized that disassembly of actin filaments or microtubules may impact endothelial vascular endothelial growth factor (VEGF) receptor-2 (VEGFR2) expression as a critical determinant of angiogenesis. We therefore investigated the effect of actin filament- and microtubule-disrupting agents on VEGFR1 and VEGFR2 expression by endothelial cells. Microtubule (MT) disassembly greatly inhibited endothelial VEGFR2 expression, whereas VEGFR1 expression levels remained largely unchanged. These suppressive effects were neither conveyed by increased VEGFR2 shedding nor by shortened protein half-life, suggesting that transcriptional mechanisms account for the observed effects. In line with this conclusion, MT disruption significantly suppressed endothelial VEGFR2 mRNA accumulation. The treatment considerably decreased transcriptional activity of 5'-deletional VEGFR2 promoter gene constructs. MT disruption-mediated repression was conveyed by a GC-rich region harboring two consensus Sp1-binding sites. Electrophoretic mobility-shift assay analysis demonstrated that constitutive Sp1-dependent DNA binding is decreased by MT disassembly. In addition, we provide evidence for additional post-transcriptional regulatory mechanisms, as the VEGFR2 mRNA half-life is significantly reduced by MT-disrupting agents. Hence, both inhibition of the rate of gene transcription and increased mRNA turnover represent critical molecular mechanisms by which MT disruption inhibits VEGFR2 expression.
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Colchicina/farmacología , Endotelio Vascular/metabolismo , Microtúbulos/efectos de los fármacos , Nocodazol/farmacología , Moduladores de Tubulina/farmacología , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Vinblastina/farmacología , Actinas/efectos de los fármacos , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Células Cultivadas , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Humanos , Procesamiento Postranscripcional del ARN , ARN Mensajero/metabolismo , Factor de Transcripción Sp1/metabolismo , Tiazolidinas/farmacología , Transcripción Genética , Receptor 2 de Factores de Crecimiento Endotelial Vascular/efectos de los fármacosRESUMEN
Metastasis continues to be the major cause of morbidity and mortality in malignant melanoma. In our study, we explored whether inhibition of VEGFR-1 or VEGFR-2 signaling conveys distinct suppressive effects on B16 melanoma subcutaneous growth and metastasis formation. The inhibition of VEGFR-1 or -2 alone had no significant influence on both melanoma growth and metastasis formation. In contrast, simultaneous blockade of VEGFR-1 and -2 signaling strongly suppressed progression in both B16 tumor models. There was no expression of VEGFR-1 or -2 detectable on the B16 cells used, excluding the melanoma cells as direct therapeutic targets. Analyzing the contribution of progenitor-like cells during melanoma metastasis formation, we observed an enhanced proliferation and mobilization of VEGFR-1+ myeloid and VEGFR-2+ endothelial cells with progenitor potential by the induction of melanoma lung metastasis, which was not influenced by interference with VEGFR signaling. These results indicate that the antimetastatic effects exerted by combined inhibition of VEGFR-1 and -2 signaling were mediated via targeting cell populations other than progenitors only. Sole inhibition of VEGFR-1 signaling led to a strong reduction of the CD45-positive inflammatory infiltrate in the tumor tissue. However, the formation of lung metastasis was not affected, indicating that inhibition of the inflammatory response was not sufficient to efficiently block B16 melanoma metastasis development. Taken together, our data suggest that in the utilized B16 tumor models the blockade of both the inflammatory and the VEGFR-2-dependent angiogenic response are necessary to effectively inhibit solid tumor growth and formation of lung metastasis by B16 melanoma cells.
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Melanoma Experimental/terapia , Receptor 1 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Animales , Movilización de Célula Madre Hematopoyética , Humanos , Antígenos Comunes de Leucocito/análisis , Neoplasias Pulmonares/prevención & control , Neoplasias Pulmonares/secundario , Melanoma Experimental/patología , Melanoma Experimental/secundario , Ratones , Ratones Endogámicos C57BL , Retroviridae/genética , Receptor 1 de Factores de Crecimiento Endotelial Vascular/fisiología , Receptor 2 de Factores de Crecimiento Endotelial Vascular/fisiologíaAsunto(s)
Aminoquinolinas/uso terapéutico , Antineoplásicos/uso terapéutico , Carcinoma in Situ/tratamiento farmacológico , Melanoma/tratamiento farmacológico , Mucosa Bucal/patología , Neoplasias de la Boca/tratamiento farmacológico , Neoplasias Cutáneas/tratamiento farmacológico , Administración Tópica , Anciano , Femenino , Humanos , ImiquimodRESUMEN
Calciphylaxis is a very uncommon and severe disease which mainly appears in patients with chronic renal insufficiency. It presents with ischemia and necrosis of the skin, subcutaneous adipose tissue, muscles and rarely viscera. The pathogenetic mechanisms inducing calciphylaxis are for the most part unknown. The mortality rate of 80% in the first year is very high. Patients experience marked pain, recurrent infections and the constant risk of secondary sepsis. Even multidisciplinary therapeutic strategies are limited, although there are recent case reports providing promising new therapeutic options including sodium thiosulfate and cinacalcet. This review summarizes the important aspects of diagnosis, pathogenesis, prevention and the possible therapeutic strategies of this intriguing, rare and often fatal disease.
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Calcifilaxia , Factores de Edad , Calcifilaxia/sangre , Calcifilaxia/diagnóstico , Calcifilaxia/tratamiento farmacológico , Calcifilaxia/epidemiología , Calcifilaxia/etiología , Calcifilaxia/mortalidad , Calcifilaxia/patología , Calcifilaxia/prevención & control , Calcifilaxia/cirugía , Calcifilaxia/terapia , Calcio/sangre , Cinacalcet , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Humanos , Oxigenoterapia Hiperbárica , Hiperparatiroidismo/complicaciones , Incidencia , Fallo Renal Crónico/complicaciones , Masculino , Persona de Mediana Edad , Naftalenos/uso terapéutico , Obesidad/complicaciones , Paratiroidectomía , Fosfatos/sangre , Diálisis Renal/efectos adversos , Factores de Riesgo , Factores Sexuales , Tiosulfatos/uso terapéutico , Factores de TiempoRESUMEN
To explore the initial steps by which transplanted mesenchymal stem cells (MSCs) interact with the vessel wall in the course of extravasation, we studied binding of human MSCs to endothelial cells (ECs). In a parallel plate flow chamber, MSCs bound to human umbilical vein ECs (HUVECs) similar to peripheral-blood mononuclear cells (PBMCs) or CD34(+) hematopoietic progenitors at shear stresses of up to 2 dynes/cm(2). This involved rapid extension of podia, rolling, and subsequent firm adhesion that was increased when ECs were prestimulated with TNF-alpha. MSC binding was suppressed when ECs were pretreated with function-blocking anti-P-selectin antibody, and rolling of MSCs was induced on immobilized P-selectin, indicating that P-selectin was involved in this process. Preincubation of HUVECs with anti-VCAM-1 or of MSCs with anti-VLA-4 antibodies suppressed binding of MSCs to HUVECs but did not enhance inhibition by anti-P-selectin, indicating that both P-selectin and VCAM-1 are equally required for this process. Intravital microscopy demonstrated the capacity of MSCs to roll and adhere to postcapillary venules in vivo in a mouse model in a P-selectin-dependent manner. Thus, MSCs interact in a coordinated fashion with ECs under shear flow, engaging P-selectin and VCAM-1/VLA-4.
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Antígenos CD34 , Moléculas de Adhesión Celular/biosíntesis , Movimiento Celular , Células Endoteliales/metabolismo , Células Madre Mesenquimatosas/metabolismo , Venas Umbilicales/metabolismo , Animales , Adhesión Celular , Células Endoteliales/citología , Femenino , Humanos , Masculino , Células Madre Mesenquimatosas/citología , Ratones , Microscopía por Video , Estrés Mecánico , Venas Umbilicales/citologíaRESUMEN
An 81-year-old women presented with monstrous subcutaneous mobile masses on the ventral and ventrolateral surfaces of her thighs. Radiography as well as computer tomography showed extensive soft tissue calcifications. We interpreted these alterations as dystrophic calcinosis cutis, most likely resulting from repeated subcutaneous PAS infusions for the treatment of pulmonary tuberculosis.
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Ácido Aminosalicílico/efectos adversos , Antituberculosos/efectos adversos , Calcinosis/inducido químicamente , Enfermedades de la Piel/inducido químicamente , Tuberculosis Pulmonar/tratamiento farmacológico , Anciano de 80 o más Años , Ácido Aminosalicílico/administración & dosificación , Antituberculosos/administración & dosificación , Calcinosis/diagnóstico por imagen , Progresión de la Enfermedad , Femenino , Humanos , Inyecciones Subcutáneas , Enfermedades de la Piel/diagnóstico por imagen , Tejido Subcutáneo/diagnóstico por imagen , Tejido Subcutáneo/efectos de los fármacos , Muslo , Tomografía Computarizada por Rayos XRESUMEN
Ample evidence suggests that many of the in vivo anti-metastatic effects by heparins reflect their actions on P-selectin-mediated binding. We hypothesized that the ability of widely used heparins and derivatives to interfere with P-selectin-dependent tumour cell interactions under flow in vitro could be used to identify anticoagulants with advanced inhibitory functions on experimental blood-borne metastasis in vivo. To test this assumption, the impact of unfractionated heparin, the low-molecular-weight heparins (LMWH) nadroparin and enoxaparin, and the synthetic pentasaccharide fondaparinux on P-selectin-dependent tumour interactions in vitro and metastasis formation in vivo were evaluated. Our data revealed that these commonly used anticoagulants widely differ in their potential to interfere with P-selectinmediated cell binding. Importantly, the superior inhibitory capacity on P-selectin function of unfractionated heparin and LMWH nadroparin as opposed to LMWH enoxaparin and synthetic heparin pentasaccharide fondaparinux strongly correlated to the inhibitory potency of each in inhibiting experimental lung metastasis in vivo. Hence, P-selectin inhibition may constitute a valuable feature to identify anticoagulants that are suitable for anticancer therapy.
Asunto(s)
Anticoagulantes/farmacología , Antineoplásicos/farmacología , Heparina/farmacología , Neoplasias Pulmonares/prevención & control , Melanoma Experimental/metabolismo , Selectina-P/metabolismo , Animales , Adhesión Celular/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Neoplasias Pulmonares/secundario , Melanoma Experimental/irrigación sanguínea , Melanoma Experimental/patología , Ratones , Nadroparina/farmacologíaRESUMEN
Targeting the vascular endothelial growth factor (VEGF) in combination with standard chemotherapy has recently proved successful in the treatment of different types of advanced cancer. The achievements of combinatorial anti-VEGF monoclonal antibody bevacizumab (BEV) renewed the confidence in targeted antiangiogenic approaches to constitute a complementary therapeutic modality in addition to surgery, radiotherapy and chemotherapy. While several second-generation multitargeted tyrosine kinase inhibitors show promise in defined tumor entities, these novel antiangiogenic compounds have yet to meet or exceed the efficacy of combinatorial BEV therapy in ongoing clinical trials. Current developments of targeted antiangiogenic agents include their use in the adjuvant setting and the combination of different antiangiogenesis inhibitors to take a more comprehensive approach in blocking tumor angiogenesis. The identification of surrogate markers that can monitor the activity and efficacy of antiangiogenic drugs in patients belongs to the most critical challenges to exploit the full potential of antiangiogenic therapies. The opportunities and obstacles in further development of growth factor- and growth factor receptor-targeted antiangiogenic approaches for advanced cancer, including malignant melanoma, will be discussed herein with particular reference to selected ongoing clinical trials.
Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Neoplasias Cutáneas/tratamiento farmacológico , Inhibidores de la Angiogénesis/farmacología , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados , Bevacizumab , Neoplasias Colorrectales/tratamiento farmacológico , Terapia Combinada , Factor de Crecimiento Epidérmico/antagonistas & inhibidores , Humanos , Factor de Crecimiento Derivado de Plaquetas/antagonistas & inhibidores , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidoresRESUMEN
To investigate the role of the monomeric guanosine triphosphatase (GTPase) Rho on migration of hematopoietic progenitor cells (HPC), we employed different clostridial toxins which inhibit the Rho family of GTPases. Pretreatment with C2I-C3, a cell-accessible C3 transferase fusion protein that targets Rho, increased chemokinetic migration of the factor-dependent multipotent cell line Factor Dependent Cell Paterson with mixed lineage differentiation potential (FDCP-mix) and of primary lineage marker-depleted HPC in vitro. In contrast, treatment with lethal toxin (LT) from Clostridium sordellii, which predominantly inactivates Rac, and with toxin B from C. difficile, which inactivates Rho, Rac and Cdc42, decreased in vitro migration. When HPC pretreated with LT or toxin B were transplanted into mice, homing to the bone marrow was impaired, whereas C2I-C3 treatment did not alter HPC homing. However, in a competitive hematopoietic repopulation experiment in C57BL/6 mice, pretreatment of bone marrow cells with any of the inhibitors, including the Rho inhibitor C2I-C3, resulted in suppressed donor-type hematopoiesis. Our data indicate that whereas Rac supports HPC cell cycling, migration, short-term homing and hematopoietic regeneration, Rho coordinates down-regulation of HPC migration and is required for hematopoietic regeneration.
Asunto(s)
Movimiento Celular/inmunología , Células Madre Hematopoyéticas/metabolismo , Proteínas de Unión al GTP rho/metabolismo , ADP Ribosa Transferasas/metabolismo , Animales , Toxinas Botulínicas/farmacología , Línea Celular , Movimiento Celular/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas/efectos de los fármacos , Ratones , Proteínas de Unión al GTP rac/metabolismo , Proteínas de Unión al GTP rho/efectos de los fármacosRESUMEN
New blood vessel formation is essential for the growth and metastasis of many cancers. As a result, antitumor activities of various angiogenesis inhibitors have been intensely explored in various tumors. Recent preclinical studies suggest that certain conventional cytotoxic agents can function as antiangiogenic drugs when administered at comparatively low doses on a continuous or very frequent schedule. Such antiangiogenic 'metronomic' scheduling of chemotherapy without extended rest periods has been shown to exert significant therapeutic antitumor efficacy with very limited toxicity in different tumor models. Combining metronomic low-dose chemotherapy regimens with specific angiogenesis inhibitors further increases efficacy. Based on the promising preclinical studies, it is anticipated that metronomic chemotherapy in combination with angiogenesis inhibitors will prove effective in clinical trials in terms of survival prolongation. While considerable progress may derive from larger randomized clinical studies, only joint efforts between basic and clinical research will ultimately advance the new paradigm of long-term metronomic antiangiogenic chemotherapy, which carries the prospect of turning cancer into a more controllable chronic disease at minimal toxicity.