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1.
Blood ; 125(1): 124-32, 2015 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-25359993

RESUMEN

Anaplastic large cell lymphoma (ALCL) is a distinct entity of T-cell lymphoma that can be divided into 2 subtypes based on the presence of translocations involving the ALK gene (ALK(+) and ALK(-) ALCL). The interferon regulatory factor 4 (IRF4) is known to be highly expressed in both ALK(+) and ALK(-) ALCLs. However, the role of IRF4 in the pathogenesis of these lymphomas remains unclear. Here we show that ALCLs of both subtypes are addicted to IRF4 signaling, as knockdown of IRF4 by RNA interference was toxic to ALCL cell lines in vitro and in ALCL xenograft mouse models in vivo. Gene expression profiling after IRF4 knockdown demonstrated a significant downregulation of a variety of known MYC target genes. Furthermore, our analyses revealed that MYC is a primary target of IRF4, identifying a novel regulatory mechanism of MYC expression and its target gene network in ALCL. MYC, itself, is essential for ALCL survival, as both knockdown of MYC and pharmacologic inhibition of MYC signaling were toxic to ALCL cell lines. Collectively, our results demonstrate that ALCLs are dependent on IRF4 and MYC signaling and that MYC may represent a promising target for future therapies.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Factores Reguladores del Interferón/metabolismo , Linfoma Anaplásico de Células Grandes/genética , Linfoma Anaplásico de Células Grandes/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Animales , Línea Celular Tumoral , Supervivencia Celular , Femenino , Perfilación de la Expresión Génica , Humanos , Linfoma/metabolismo , Ratones , Ratones Endogámicos NOD , Ratones SCID , Trasplante de Neoplasias , Interferencia de ARN , Retroviridae/metabolismo , Transducción de Señal
2.
In Vitro Cell Dev Biol Anim ; 51(2): 183-91, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25270685

RESUMEN

In the present study, purified human cord blood stem cells were co-cultivated with murine hepatic alpha mouse liver 12 (AML12) cells to compare the effect on endodermal stem cell differentiation by either direct cell-cell interaction or by soluble factors in conditioned hepatic cell medium. With that approach, we want to mimic in vitro the situation of preclinical transplantation experiments using human cells in mice. Cord blood stem cells, cultivated with hepatic conditioned medium, showed a low endodermal differentiation but an increased connexin 32 (Cx32) and Cx43, and cytokeratin 8 (CK8) and CK19 expression was monitored by reverse transcription polymerase chain reaction (RT-PCR). Microarray profiling indicated that in cultivated cord blood cells, 604 genes were upregulated 2-fold, with the highest expression for epithelial CK19 and epithelial cadherin (E-cadherin). On ultrastructural level, there were no major changes in the cellular morphology, except a higher presence of phago(ly)some-like structures observed. Direct co-culture of AML12 cells with cord blood cells led to less incisive differentiation with increased sex-determining region Y-box 17 (SOX17), Cx32 and Cx43, as well as epithelial CK8 and CK19 expressions. On ultrastructural level, tight cell contacts along the plasma membranes were revealed. FACS analysis in co-cultivated cells quantified dye exchange on low level, as also proved by time relapse video-imaging of labelled cells. Modulators of gap junction formation influenced dye transfer between the co-cultured cells, whereby retinoic acid increased and 3-heptanol reduced the dye transfer. The study indicated that the cell-co-cultured model of human umbilical cord blood cells and murine AML12 cells may be a suitable approach to study some aspects of endodermal/hepatic cell differentiation induction.


Asunto(s)
Sangre Fetal/citología , Hepatocitos/fisiología , Células Madre/citología , Animales , Biomarcadores/análisis , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/genética , Técnicas de Cocultivo , Conexina 43/genética , Conexinas/genética , Medios de Cultivo Condicionados/farmacología , Expresión Génica , Hepatocitos/citología , Humanos , Ratones , Análisis por Micromatrices , Microscopía Electrónica , Reacción en Cadena en Tiempo Real de la Polimerasa , Células Madre/fisiología , Proteína beta1 de Unión Comunicante
3.
In Vitro Cell Dev Biol Anim ; 48(3): 165-74, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22311374

RESUMEN

The aims of this study were to analyze the spontaneous differentiation of human embryonic stem cells in vitro and in vivo and to investigate the influence of in vitro partial differentiation on in vivo teratoma formation in immunodeficient mice. Standardized methods are needed for long-term cultivation of undifferentiated stem cells and the multilineage cells that spontaneously differentiate from them. Accordingly, SA002 human embryonic stem cells were cultured on irradiated mouse embryonic fibroblasts cells, on irradiated human foreskin fibroblasts, or were cultured feeder-free using matrigel. Expression of marker protein transcripts was analyzed in undifferentiated and differentiated stem cells using real-time PCR, and both types of stem cells were transplanted subcutaneously into immunodeficient NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ mice to test for teratoma formation. Teratoma histology and expression profiles were subsequently characterized. Cells cultured using different conditions and morphologically undifferentiated cells had comparable marker expression profiles, showing high expression levels of markers for pluripotency and low-to-moderate expression levels of germ layer markers. Cells showing spontaneous differentiation that were cultured in feeder-free conditions in the absence of basic fibroblast growth factor demonstrated slight upregulation of sex determining region Y-box 17, connexin 32, and albumin expression at early time points, as well as expression of octamer-binding transcription factor 4, proteoglycan epitopes on podocalyxin (Trafalgar), and alkaline phosphatase. At later time points, expression of hepatocyte nuclear factor-3-beta, and hepatocyte nuclear factor-4-alpha and alpha fetoprotein was upregulated, whereas beta-3-tubulin, chemokine receptor, nestin, sex-determining region Y-box 17, and connexin 32 were downregulated. Expression of pluripotency markers remained high, and hematopoetic markers were not expressed. SA002 cells that showed spontaneous partial differentiation in vitro had a low teratoma formation capacity in vivo. Cells that were partially differentiated led to slower growing teratomas with more uniform histology.


Asunto(s)
Diferenciación Celular , Linaje de la Célula , Células Cultivadas/citología , Células Madre Embrionarias/citología , Células Madre Pluripotentes/citología , Animales , Células Madre Embrionarias/metabolismo , Factores de Crecimiento de Fibroblastos/metabolismo , Fibroblastos/citología , Regulación del Desarrollo de la Expresión Génica , Humanos , Ratones , Células Madre Pluripotentes/metabolismo , Teratoma/metabolismo
4.
Int J Oncol ; 35(4): 901-8, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19724928

RESUMEN

Transforming growth factor-beta1 (TGF-beta1) is overexpressed in a variety of malignant epithelial tumors and was suggested to be a marker of colorectal cancer. Moreover, there is growing evidence that TGF-beta1 contributes to tumor progression by regulating tumor cell proliferation and differentiation, inducing a favorable tumor microenvironment, promoting migration and invasion, and suppressing macrophage cytotoxicity. Therefore, we stably transfected an anti-TGF-beta1 hammerhead ribozyme into the human colorectal adenocarcinoma cell line HRT-18. Expression of this ribozyme resulted in significant inhibition of TGF-beta1 expression on mRNA and protein level. This was associated with an enhanced tumor cell differentiation and a reduced tumor growth in vivo. The capability of tumor cells to suppress ROI production of co-cultivated human macrophages was abrogated in transfectants. Taken together, inhibition of TGF-beta1 in colorectal carcinoma cells might be an interesting therapeutic tool leading to reduced tumor cell growth and increased macrophage cytotoxicity. Thus, a gene-therapeutic approach using anti-TGF-beta1 ribozyme in combination with established anti-tumor agents is of great promise.


Asunto(s)
Adenocarcinoma/terapia , Neoplasias Colorrectales/terapia , Terapia Genética , Tolerancia Inmunológica , ARN Catalítico/biosíntesis , Factor de Crecimiento Transformador beta1/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/inmunología , Adenocarcinoma/patología , Animales , Adhesión Celular , Diferenciación Celular/genética , Línea Celular Tumoral , Proliferación Celular , Técnicas de Cocultivo , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/patología , Regulación hacia Abajo , Femenino , Humanos , Macrófagos/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Ratones SCID , ARN Catalítico/genética , Especies Reactivas de Oxígeno/metabolismo , Factores de Tiempo , Transfección , Factor de Crecimiento Transformador beta1/genética , Ensayos Antitumor por Modelo de Xenoinjerto
5.
Oncogene ; 22(54): 8653-61, 2003 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-14647459

RESUMEN

Cyclooxygenases, particularly COX-2, play an important role in tumor development and progression. We have previously shown that COX-2 expression is an independent prognostic factor in human ovarian carcinoma. In this study, we investigated the effects of the inhibition of COX isoforms by the NSAID NS-398 as well as by COX-isoform-specific RNA interference (RNAi) in the human ovarian carcinoma cell lines OVCAR-3 and SKOV-3. OVCAR-3 cells showed a constitutive expression of COX-1 and an induction of high levels of COX-2 and PGE(2) after stimulation with interleukin-1beta. In contrast, SKOV-3 cells were negative for both COX isoforms. In OVCAR-3 cells, PGE(2) production was inhibited by NS-398 in concentrations of 1 microM and by a COX-2-specific silencing RNA (siRNA), while a COX-1-specific siRNA did not have an effect. This suggests that COX-2 is the major source of PGE(2) in this cell line. To dissociate COX-2-specific and non-COX-2-specific effects on cell proliferation, a proliferation assay was performed after incubation of cells with NS-398 and COX siRNAs. NS-398 induced an inhibition of cell proliferation at concentrations of 50-500 microM, which are above the concentrations needed for the inhibition of PGE(2) production. This inhibitory effect was present in the COX-positive cell line OVCAR-3 as well as in the COX-negative cell line SKOV-3 and could not be reverted by addition of exogenous PGE(2). Neither COX-1- nor COX-2-specific siRNAs had an effect on cell proliferation of OVCAR-3 cells. Cell cycle analysis showed an increased accumulation of cells in the G0/G1 phase after treatment with NS-398, but not with COX siRNAs. These experiments suggest that NS-398 reduced cell proliferation in ovarian carcinoma cells by induction of G0/G1 cell cycle arrest independent of COX-2 inhibition. Our study shows that specific inhibition of COX isoforms by RNAi could be used to dissociate effects of NSAIDs. Furthermore, our results suggest that cell cycle arrest is one of the primary mechanisms responsible for the antiproliferative effects of NS-398 on ovarian carcinoma cells.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Fase G1/efectos de los fármacos , Isoenzimas/antagonistas & inhibidores , Nitrobencenos/farmacología , Neoplasias Ováricas/tratamiento farmacológico , Interferencia de ARN , Fase de Descanso del Ciclo Celular/efectos de los fármacos , Sulfonamidas/farmacología , División Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ciclooxigenasa 1 , Ciclooxigenasa 2 , Dinoprostona/biosíntesis , Femenino , Regulación Enzimológica de la Expresión Génica , Humanos , Isoenzimas/genética , Proteínas de la Membrana , Neoplasias Ováricas/enzimología , Neoplasias Ováricas/patología , Prostaglandina-Endoperóxido Sintasas/genética
6.
Cancer ; 97(12): 2978-87, 2003 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-12784332

RESUMEN

BACKGROUND: Cyclooxygenases regulate the production of prostaglandins and play a role in tumor development and progression. The authors investigated the prognostic impact of expression of the cyclooxygenase (COX) isoforms, COX-1 and COX-2, on disease-free survival and progression-free survival in patients with primary breast carcinoma as well as the association between COX expression and other clinicopathologic parameters. METHODS: In this study COX isoform expression was determined by immunohistochemistry in a cohort of 221 patients with primary breast carcinoma. RESULTS: Expression of COX-2 was detected in 36% of breast carcinoma samples and was associated significantly with several clinicopathologic parameters, including positive lymph node status (P < 0.0005), larger tumor size (P < 0.0005), poor differentiation (P < 0.0005), vascular invasion (P = 0.03), and negative estrogen receptor status (P = 0.04). In contrast, COX-1 was expressed in 45% of tumors and was associated with smaller tumor size (P = 0.02) and with negative lymph node status (P = 0.01). In a univariate survival analysis, a significant association was observed between elevated COX-2 expression and decreases in disease-free survival (P = 0.0007) and overall survival (P = 0.02). In a multivariate analysis, expression of COX-2 was of borderline significance for disease-free survival (relative risk, 1.90; 95% confidence interval, 1.00-3.59), adjusting for tumor size, histologic grade, number of positive lymph nodes, and patient age. Elevated expression of COX-1 in tumor tissue had no statistically significant influence on patient prognosis. CONCLUSIONS: The current data suggest that increased expression of COX-2 may play a role in the progression of primary breast carcinoma. It remains to be investigated whether treatment with selective inhibitors of COX-2 may be an additional therapeutic option for patients with breast carcinoma.


Asunto(s)
Neoplasias de la Mama/enzimología , Neoplasias de la Mama/mortalidad , Carcinoma/enzimología , Isoenzimas/metabolismo , Prostaglandina-Endoperóxido Sintasas/metabolismo , Adulto , Neoplasias de la Mama/patología , Carcinoma/mortalidad , Carcinoma/patología , Estudios de Cohortes , Ciclooxigenasa 1 , Ciclooxigenasa 2 , Supervivencia sin Enfermedad , Femenino , Humanos , Metástasis Linfática , Proteínas de la Membrana , Persona de Mediana Edad , Pronóstico , Análisis de Supervivencia
7.
Cancer Lett ; 195(1): 101-9, 2003 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-12767518

RESUMEN

The development of therapeutic strategies for inhibition of peritoneal dissemination and invasion would be central for the treatment of ovarian carcinoma. In the microenvironment of ovarian carcinomas, various inflammatory cytokines like tumor necrosis factor alpha (TNF-alpha) are present. In this study we investigated the role of inflammatory cytokines in the regulation of invasion of SKOV-3 ovarian carcinoma cells in-vitro. Treatment of cells with TNF-alpha or interleukin 1beta (IL-1beta) lead to increased phosphorylation of the stress-activated p38 mitogen-activated protein kinase (p38MAPK). Furthermore, TNF-alpha as well as IL-1beta stimulated matrigel invasion of tumor cells. An inhibitor of stress-activated protein kinase pathways, the cytokine-suppressive anti-inflammatory drug (CSAID) SB203580 inhibited invasion of cytokine-stimulated SKOV-3 cells. The MEK-1 inhibitor PD98059 similarly inhibited invasion of cytokine-stimulated cells, but to a lesser extent. Expression of mRNA and protein levels of matrix metalloproteinase-1 (MMP-1) by SKOV-3 cells could be stimulated by inflammatory cytokines and inhibited by SB203580, and partially also by PD98059. Our results show that CSAIDs reduce invasion and MMP expression of ovarian carcinoma cells. Further studies are required to investigate whether inhibition of cytokine-induced signal transduction may be of value in therapy of ovarian carcinomas in-vivo.


Asunto(s)
Adenocarcinoma/patología , Antiinflamatorios no Esteroideos/farmacología , Citocinas/antagonistas & inhibidores , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Imidazoles/farmacología , Metaloproteinasa 1 de la Matriz/biosíntesis , Proteínas de Neoplasias/biosíntesis , Neoplasias Ováricas/patología , Piridinas/farmacología , Adenocarcinoma/enzimología , Colágeno , Combinación de Medicamentos , Inducción Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Femenino , Flavonoides/farmacología , Humanos , Inflamación , Interleucina-1/farmacología , Laminina , MAP Quinasa Quinasa 1 , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Metaloproteinasa 1 de la Matriz/genética , Metaloproteinasa 3 de la Matriz/biosíntesis , Metaloproteinasa 3 de la Matriz/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Invasividad Neoplásica , Proteínas de Neoplasias/genética , Neoplasias Ováricas/enzimología , Fosforilación/efectos de los fármacos , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteoglicanos , ARN Mensajero/biosíntesis , ARN Neoplásico/biosíntesis , Células Tumorales Cultivadas/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos
8.
Eur J Cell Biol ; 82(1): 1-8, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12602943

RESUMEN

The production of abundant connective tissue within malignant tumors, the so-called desmoplastic stromal reaction, is a hallmark of colorectal adenocarcinomas. This stroma is produced to a large extent by myofibroblasts and contains various amounts of collagens (type I, III, and V), chondroitin sulfate proteoglycan, hyaluronic acid, fibronectin, and tenascin-C. In this study we have established a monolayer coculture model between two different colorectal adenocarcinoma cell lines (HRT-18, and CX-2) and colonic fibroblasts (CCD-18) to investigate the mechanisms regulating (i) the production of extracellular matrix (ECM) components, (ii) the induction of myofibroblastic differentiation, and (iii) cellular proliferation. We found that TGFbeta1 and FGF-2 stimulated ECM synthesis of fibroblasts. Myofibroblastic differentiation was stimulated by TGFbeta1 but suppressed by FGF-2. There was a mutual stimulation of proliferation between fibroblasts and carcinoma cells. The analogies with ECM components expressed in cocultures and colorectal adenocarcinoma samples suggest that the coculture model used in this study is useful to study tumor cell-fibroblast interactions.


Asunto(s)
Adenocarcinoma/metabolismo , División Celular/fisiología , Neoplasias Colorrectales/metabolismo , Tejido Conectivo/metabolismo , Proteínas de la Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/patología , Comunicación Celular/efectos de los fármacos , Comunicación Celular/fisiología , Técnicas de Cultivo de Célula/métodos , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/fisiología , División Celular/efectos de los fármacos , Técnicas de Cocultivo , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Tejido Conectivo/efectos de los fármacos , Tejido Conectivo/ultraestructura , Proteínas de la Matriz Extracelular/efectos de los fármacos , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Factor 2 de Crecimiento de Fibroblastos/farmacología , Fibroblastos/efectos de los fármacos , Fibroblastos/ultraestructura , Humanos , Mediadores de Inflamación/metabolismo , Microscopía Electrónica , Modelos Biológicos , Células del Estroma/efectos de los fármacos , Células del Estroma/metabolismo , Células del Estroma/ultraestructura , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta/farmacología , Factor de Crecimiento Transformador beta1 , Células Tumorales Cultivadas
9.
Int J Cancer ; 102(5): 507-13, 2002 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-12432554

RESUMEN

The mitogen-activated protein kinase phosphatase-1, MKP-1 (CL100) is involved in inactivation of MAP-kinase pathways, regulation of stress-responses and suppression of apoptosis. We investigated expression of MKP-1 in 90 cases of primary ovarian tumors, 11 normal ovaries as well as 4 ovarian carcinoma cell lines. Immunohistochemical expression of MKP-1 protein was reduced in tissue from LMP tumors and invasive ovarian carcinomas compared to normal ovaries and cystadenomas. A moderate to strong expression of MKP-1 was detected in 57.6% of invasive ovarian carcinomas. In a descriptive univariate survival analysis, MKP-1 expression was a prognostic marker for shorter progression-free survival of patients with invasive ovarian carcinomas. Patients with carcinomas positive for MKP-1 had a median progression-free survival of only 18.3 months compared to 40.6 months for patients with carcinomas negative for MKP-1 (log-rank test, p = 0.019). Other prognostic parameters for progression-free survival were FIGO stage, grade and pT stage. In an exploratory multivariate analysis, we found that MKP-1 expression as well as FIGO stage and grade were independent prognostic factors for progression-free survival. In contrast to progression-free survival, we did not find any influence of MKP-1 expression on patient overall survival. We investigated expression and regulation of MKP-1 mRNA by Northern Blot in vitro using 4 ovarian carcinoma cell lines (SKOV-3, OVCAR-3, CAOV-3, OAW-42). MKP-1 mRNA was inducible by interleukin-1beta and tumor necrosis factor-alpha in SKOV-3 and OVCAR-3 cells, whereas CAOV-3 and OAW-42 expressed MKP-1 mRNA constitutively. In OVCAR-3 cells MKP-1 mRNA levels were strongly inducible upon treatment of cells with cisplatin. Our data indicate that MKP-1 is expressed in a subset of ovarian carcinomas and regulated by inflammatory mediators. Expression of MKP-1 may be associated with shorter progression-free survival times. Further studies are needed to determine whether MKP-1 expression is a clinically useful marker to estimate patient prognosis as well as the response to chemotherapy.


Asunto(s)
Carcinoma/enzimología , Proteínas de Ciclo Celular , Proteínas Inmediatas-Precoces/metabolismo , Neoplasias Ováricas/enzimología , Fosfoproteínas Fosfatasas , Proteínas Tirosina Fosfatasas/metabolismo , Carcinoma/patología , Cisplatino/farmacología , Cistoadenoma/enzimología , Fosfatasa 1 de Especificidad Dual , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Proteínas Inmediatas-Precoces/genética , Inmunohistoquímica , Neoplasias Ováricas/patología , Ovario/enzimología , Proteína Fosfatasa 1 , Proteínas Tirosina Fosfatasas/genética , ARN Mensajero/biosíntesis , Estudios Retrospectivos , Análisis de Supervivencia , Células Tumorales Cultivadas
10.
Electrophoresis ; 23(7-8): 1174-84, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11981867

RESUMEN

The use of three-dimensional cell culture models, so-called multicellular tumor spheroids, is a special approach in experimental cancer research, because spheroids are similar to in vivo tumors in structural as well as functional sense. Cells grown in spheroids exhibit alterations of cell cycle regulation, induction of apoptosis and differentiation and can acquire multidrug resistance. In this study we investigated the protein expression in human colorectal cancer cells grown in monolayer and in spheroid cultures using proteomics. Evaluation by computer-assisted image analysis revealed overexpression of three cytokeratin 18 fragments that were generated in vivo. Cytokeratin 18 has previously been described as a target for caspase-mediated cleavage during apoptosis and our results indicate that apoptosis may take place in spheroids. Other proteins upregulated in spheroids include calreticulin precursor, a rho GDP dissociation inhibitor variant, several cytokeratins and peroxiredoxin 4. Some of these proteins have already been linked to chemoresistance and apoptotic phenomena.


Asunto(s)
Queratinas/metabolismo , Electroforesis en Gel Bidimensional , Células HT29 , Humanos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
11.
Clin Exp Metastasis ; 19(1): 79-85, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-11918086

RESUMEN

A lot of parallels have been described between invasion of malignant tumor cells and leukocyte movement during inflammatory responses. Concerning these similarities, we investigated the function of cytokine-suppressive anti-inflammatory drugs (CSAIDs), which act via inhibition of stress-activated MAP-kinases, in regulation of expression of proteolytic enzymes and in vitro invasion of malignant melanoma cells. The p38MAPK inhibitor SB203580 reduced matrigel invasion of MeWo cells by 60%, while the MEK-1 inhibitor PD98059 did not have any effect on invasion. Active p38MAPK was detected in MeWo cells by immunoblotting and confocal microscopy. Cells showed a constitutive expression of matrix-metalloproteinase (MMP)-2 as well as tissue inhibitor of metalloproteinases (TIMP)-1 and TIMP-2 mRNAs. Expression of MMP-1 or urokinase-type plasminogen activator (uPA) was not detected by Northern blot. Inhibition of p38MAPK by the specific inhibitor SB203580 resulted in downregulation of MMP-2 mRNA and protein levels as well as gelatinolytic activity, while expression levels of TIMP-1 and TIMP-2 mRNAs were not changed. The specific MEK-1 inhibitor PD98059 did not change expression of MMP-2 or TIMPs. Neither SB203580 nor PD98059 changed proliferation of cells. The results suggest that stress-activated protein kinases like p38MAPK are involved in regulation of expression of MMP-2 as well as in vitro invasion of malignant melanoma cells. Inhibitors of p38MAPK may be promising substances to interfere with a signaling cascade associated with invasion of malignant tumor cells.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Flavonoides/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Imidazoles/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Metaloproteinasa 2 de la Matriz/biosíntesis , Melanoma/enzimología , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , Invasividad Neoplásica , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Piridinas/farmacología , Northern Blotting , División Celular/efectos de los fármacos , Inducción Enzimática/efectos de los fármacos , Gelatina/metabolismo , MAP Quinasa Quinasa 1 , Metaloproteinasa 2 de la Matriz/genética , Melanoma/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/fisiología , Proteínas Quinasas Activadas por Mitógenos/fisiología , Proteínas de Neoplasias/fisiología , Fosforilación/efectos de los fármacos , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/fisiología , ARN Mensajero/biosíntesis , ARN Neoplásico/biosíntesis , Inhibidor Tisular de Metaloproteinasa-1/biosíntesis , Inhibidor Tisular de Metaloproteinasa-1/genética , Inhibidor Tisular de Metaloproteinasa-2/biosíntesis , Inhibidor Tisular de Metaloproteinasa-2/genética , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/enzimología , Proteínas Quinasas p38 Activadas por Mitógenos
12.
Am J Pathol ; 160(3): 893-903, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11891188

RESUMEN

Cyclooxygenase-2 (COX-2) is the rate-limiting enzyme in prostanoid biosynthesis and is involved in tumor progression. We investigated expression of COX-1 and COX-2 in cell lines and tumors from ovarian carcinomas. Expression of COX-2 mRNA and protein was detectable in three of five ovarian carcinoma cell lines and was inducible by interleukin-1beta or phorbolester in a subset of cell lines. Prostaglandin E(2) (PGE(2)) production could be inhibited by the selective COX-2 inhibitor NS-398. In malignant ascites of ovarian carcinomas significantly increased levels of PGE(2) were found compared to other carcinomas or nonmalignant ascites (P = 0.03). We investigated expression of COX-2 by immunohistochemistry in 117 ovarian surface epithelial tumors. Expression of COX-2 was detected in 42% of 86 ovarian carcinomas and in 37% of 19 low malignant potential tumors, but not in 12 cystadenomas or 2 normal ovaries. Expression of COX-1 was detected by immunohistochemistry in 75% of 75 invasive ovarian carcinomas and in 75% of 16 low malignant potential tumors, whereas 2 samples from normal ovaries and 8 cystadenomas were positive for COX-1. In univariate survival analysis of invasive carcinomas, expression of COX-2 was associated with a significantly reduced median survival time (log rank test, P = 0.04). For patients younger than 60 years of age, this association was even more significant (P < 0.004). In contrast, expression of COX-1 was no prognostic parameter (P = 0.89). There was no significant correlation between COX-2 or COX-1 expression and other clinicopathological markers. In multivariate analysis expression of COX-2 was an independent prognostic factor for poor survival (relative risk, 2.74; 95% CI, 1.38 to 5.47). Our data indicate that COX-2 expression is an independent prognostic factor in ovarian carcinoma. Based on the results of this study, it would be interesting to investigate whether ovarian carcinoma patients with tumors positive for COX-2 would benefit from treatment with selective COX-2 inhibitors.


Asunto(s)
Biomarcadores de Tumor , Isoenzimas/biosíntesis , Neoplasias Ováricas/enzimología , Prostaglandina-Endoperóxido Sintasas/biosíntesis , Adulto , Ciclooxigenasa 1 , Ciclooxigenasa 2 , Femenino , Humanos , Proteínas de la Membrana , Persona de Mediana Edad , Análisis Multivariante , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/patología , Valor Predictivo de las Pruebas , Pronóstico , Análisis de Supervivencia , Células Tumorales Cultivadas
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