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1.
Magy Seb ; 67(3): 94-8, 2014 Jun.
Artículo en Húngaro | MEDLINE | ID: mdl-24873764

RESUMEN

CASE REPORT: Authors present the case of a 30-year-old female patient, who was admitted to the ICU because of hypertensive crisis accompanied by chest complains, cardiac decompensation, progrediating short of breath and unconsciousness. Despite the quick examinations and the prompt treatment multi-organ failure developed 3 days after admission. Investigations revealed the underlying cause, which was a left-sided suprarenal neoplasm. Hence, multidisciplinary decision was made to carry out a laparoscopic adrenalectomy urgently. The histology examination of the removed neoplasm was pheochromocytoma. In the postoperative period the condition of the patient gradually improved, her symptoms and complains settled, and finally she was discharged in a healthy condition. DISCUSSION: The diagnosis of a pheochromocytoma is a difficult task, the symptoms and complains caused by it can simulate many other illnesses. The acute crisis caused by pheochromocytoma usually can be treated conservatively, but in more severe cases with impending multi-organ failure an urgent operative treatment can be unavoidable. Though the operative risk is relatively high, the correct intra- and postoperative treatment with a quick laparoscopic procedure can be effective.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/cirugía , Adrenalectomía/métodos , Feocromocitoma/cirugía , Enfermedad Aguda , Neoplasias de las Glándulas Suprarrenales/complicaciones , Adulto , Femenino , Insuficiencia Cardíaca/etiología , Humanos , Hipertensión/etiología , Comunicación Interdisciplinaria , Laparoscopía , Feocromocitoma/complicaciones , Resultado del Tratamiento , Inconsciencia/etiología
2.
Magy Seb ; 62(1): 22-6, 2009 Feb.
Artículo en Húngaro | MEDLINE | ID: mdl-19218165

RESUMEN

Pancreatic Intraepithelial Neoplasia (PanIN1-3) and Intraductal Papillary Mucinous Neoplasms (IPMN) putative precursors of and associated to pancreatic cancer represent a distinct, however pathologically heterogenous entity. Recently a new classification and nomenclature was established. We review the clinicopathologic and cytogenetic characteristics of PanIN and IPMN highlighting the nonaggressive biological behavior of intraepithelial and intraductal neoplasms which, in part explain their favorable prognosis.


Asunto(s)
Adenocarcinoma Mucinoso/patología , Carcinoma Ductal Pancreático/patología , Carcinoma Papilar/patología , Neoplasias Pancreáticas/patología , Lesiones Precancerosas/patología , Adenocarcinoma Mucinoso/química , Biomarcadores de Tumor/análisis , Carcinoma Ductal Pancreático/química , Carcinoma Papilar/química , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Metástasis Linfática , Neoplasias Pancreáticas/química , Lesiones Precancerosas/química , Pronóstico
3.
Magy Seb ; 62(1): 30-3, 2009 Feb.
Artículo en Húngaro | MEDLINE | ID: mdl-19218167

RESUMEN

56-year-old man was admitted to our hospital 18 month after extirpation of retroperitoneal liposarcoma. We diagnosed recurrent tumor in the inguinal fossa. The tumor situated along the femoral artery and propagated to the thigh among the muscles, mimicking incarcerated femoral hernia. We performed resection with synchronous abdominal and femoral exploration. By our knowledge this is the first case report about recurrent retroperitoneal liposarcoma presenting as an incarcerated femoral hernia.


Asunto(s)
Hernia Femoral/diagnóstico , Liposarcoma/complicaciones , Liposarcoma/diagnóstico , Recurrencia Local de Neoplasia/complicaciones , Recurrencia Local de Neoplasia/diagnóstico , Diagnóstico Diferencial , Ingle , Hernia Femoral/etiología , Humanos , Liposarcoma/patología , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Espacio Retroperitoneal
4.
Magy Seb ; 62(1): 27-9, 2009 Feb.
Artículo en Húngaro | MEDLINE | ID: mdl-19218166

RESUMEN

Dermatofibrosarcoma protuberans (DFSP) is a morphologically distinct dermal/subcutaneous fibrohystiocytic neoplasm seen mainly on the trunk and the proximal extremities, which generally is regarded as a low-grade or "borderline" neoplasm. Dermatofibrosarcoma protuberans is characterized clinically by locally aggressive growth and a high rate of local recurrence, but distant metastases and tumor-related deaths are very rare. DFSP in the breast is extremely uncommon. Immunohistochemically, DFSP is characterized by positive staining for vimentin and CD34. We present a case of a 65 years old female patient with a giant DFSP developed in the sight of several excised fibroadenoma and neurofibroma treated by radical mastectomy and axillary block-dissection. Perioperative hystological and immunohistochemical images demonstrate the characteristics of the giant nonphylloid sarcoma.


Asunto(s)
Biomarcadores de Tumor/análisis , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/cirugía , Dermatofibrosarcoma/diagnóstico , Dermatofibrosarcoma/patología , Anciano , Antígenos CD34/análisis , Axila , Neoplasias de la Mama/química , Neoplasias de la Mama/patología , Transformación Celular Neoplásica/química , Transformación Celular Neoplásica/patología , Dermatofibrosarcoma/química , Dermatofibrosarcoma/cirugía , Femenino , Humanos , Inmunohistoquímica , Escisión del Ganglio Linfático , Mastectomía Radical Modificada , Vimentina/análisis
5.
Magy Seb ; 62(1): 15-21, 2009 Feb.
Artículo en Húngaro | MEDLINE | ID: mdl-19218164

RESUMEN

BACKGROUND: The present study was designed to provide an analysis of factors for angiogenesis and proliferation. MATERIAL AND METHOD: We analyzed tumor tissues from 37 rectal cancer patients with concurrent or subsequent liver metastasis underwent preoperative radiotherapy, surgery and adjuvant chemotherapy. Immunohistochemistry was used for expression of proliferation (staining with anti-Ki67: MIB-1) and for detection of microvessel density (MVD, expressed by CD34). Clinicopathological findings were compared with outcome with emphasis to IHC. RESULTS: A vascular enumeration and pN status and the time of presence of the metastases has shown prognostic role along with the factors above. Increased proliferative activity of the tumor as expressed by MIB-1 staining has no prognostic value, similarly to the localization of tumor, gender, age or grading. SUMMARY: Different prognostic and predictive factors in colorectal cancer have been reported. Higher pN status and tumor vascularisation has been linked to poor prognosis in overall survival and tumor recurrence.


Asunto(s)
Adenocarcinoma/irrigación sanguínea , Neoplasias del Colon/irrigación sanguínea , Neoplasias Hepáticas/irrigación sanguínea , Neoplasias Hepáticas/secundario , Neovascularización Patológica/diagnóstico , Adenocarcinoma/mortalidad , Adenocarcinoma/secundario , Adenocarcinoma/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/análisis , Proliferación Celular , Neoplasias del Colon/mortalidad , Neoplasias del Colon/patología , Neoplasias del Colon/cirugía , Femenino , Humanos , Inmunohistoquímica , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/cirugía , Metástasis Linfática , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Pronóstico , Modelos de Riesgos Proporcionales
6.
Mol Cancer ; 7: 42, 2008 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-18492291

RESUMEN

Gefitinib (Iressa)-a specific inhibitor of epidermal growth factor receptor (EGFR) tyrosine kinase-has been shown to suppress the activation of EGFR signaling required for cell survival and proliferation in non-small cell lung cancer (NSCLC) cell lines. We recently provided novel evidence that gefitinib-sensitive PC9 cells show normal endocytosis of EGFR: internalized EGF-EGFR complexes were transported to late endosomes/lysosomes 15 min after EGF stimulation, and then degraded within the lysosomes. However, gefitinib-resistant QG56 cells showed internalized EGFR accumulation in early endosomes after 60 min of internalization, instead of its trafficking to lysosomes, indicating an aberration in some steps of EGF-EGFR trafficking from the early endosomes to late endosomes/lysosomes. Therefore, we postulate that impairment in some steps of EGF-EGFR trafficking from early endosomes to late endosomes/lysosomes might confer gefitinib-resistance in NSCLC cell lines. To further substantiate the detailed internalization mechanism of gefitinib-sensitive and gefitinib-resistant cells, using confocal immunofluorescence microscopy, we examined the endocytic trafficking of phosphorylated EGFR (pEGFR) in the absence or presence of gefitinib. In PC9 and QG56 cells without EGF stimulation, a large number of pEGFR-positive small vesicular structures not colocalized with late endosomes/lysosomes were spread throughout the cytoplasm, and some pEGFR staining was distributed in the nucleus. This implies a novel intracellular trafficking pathway for pEGFR from cytoplasmic vesicles to the nucleus. Furthermore, an aggregated vesicular structure of early endosomes was observed in the perinuclear region of QG56 cells; it was revealed to be associated with SNX1, originally identified as a protein that interacts with EGFR. Therefore, we confirmed our previous data that an aberration in some steps of EGF-EGFR trafficking from the early endosomes to late endosomes/lysosomes occurs in QG56 cells. Furthermore, in PC9 cells, efficient phosphorylation of EGFR and rapid internalization of pEGFR was observed at 3 min after EGF stimulation; these internalized pEGFR-positive vesicles were trafficked to late endosomes at 15 min, indicating rapid trafficking of EGF-pEGFR complexes from early to late endosomes in PC9 cells. Gefitinib treatment strongly reduced the phosphorylation level of EGFR, and subsequent endocytosis of EGFR was significantly suppressed in PC9 cells. In contrast, in QG56 cells, EGFR trafficking via the early endocytic pathway was basically impaired; therefore, gefitinib appeared to slightly suppress the internalization of pEGFR. Collectively, our data provide novel evidence that extensive impairment in pEGFR endocytosis via the early endocytic pathway might confer gefitinib-resistance in QG56 cells.


Asunto(s)
Endocitosis/efectos de los fármacos , Receptores ErbB/metabolismo , Quinazolinas/farmacología , Transporte Biológico/efectos de los fármacos , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Endosomas/metabolismo , Factor de Crecimiento Epidérmico/farmacología , Gefitinib , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Lisosomas/metabolismo , Microscopía Fluorescente , Fosforilación/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Nexinas de Clasificación , Proteínas de Transporte Vesicular/metabolismo
7.
Biochem Biophys Res Commun ; 377(3): 826-31, 2008 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-18951870

RESUMEN

The close association of inflammation, angiogenesis and cancer progression is now highlighted, and in this study we especially focused on a close association of inflammation and lymphangiogenesis. We found that proinflammatory cytokine, interleukin-1beta (IL-1beta), could induce lymphangiogenesis in mouse cornea through enhanced production of potent lymphangiogenic factors, VEGF-A, VEGF-C and VEGF-D. IL-1beta-induced lymphangiogenesis, but not angiogenesis, was inhibited by administration of a selective anti-VEGF receptor-3 (VEGFR-3) neutralizing antibody. And in mouse cornea we observed recruitment of monocyte/macrophages and neutrophils by IL-1beta implanted cornea. Depletion of macrophages by a bisphosphonate encapsulated in liposomes inhibited this IL-1beta-induced lymphangiogenesis and also up-regulation of VEGF-A, VEGF-C, and VEGF-D. Furthermore, IL-1beta-induced lymphangiogenesis and angiogenesis were suppressed by NF-kappaB inhibition with marked suppression of VEGF-A, VEGF-C, and VEGF-D expression.


Asunto(s)
Interleucina-1beta/inmunología , Queratitis/inmunología , Linfangiogénesis/inmunología , Macrófagos/inmunología , FN-kappa B/metabolismo , Factor C de Crecimiento Endotelial Vascular/biosíntesis , Factor D de Crecimiento Endotelial Vascular/biosíntesis , Animales , Proliferación Celular , Córnea/irrigación sanguínea , Córnea/efectos de los fármacos , Córnea/inmunología , Difosfonatos/farmacología , Factor 2 de Crecimiento de Fibroblastos/biosíntesis , Factor 2 de Crecimiento de Fibroblastos/genética , Factor 2 de Crecimiento de Fibroblastos/farmacología , Humanos , Interleucina-1beta/farmacología , Linfangiogénesis/efectos de los fármacos , Linfangiogénesis/genética , Ratones , Ratones Endogámicos C57BL , FN-kappa B/agonistas , FN-kappa B/antagonistas & inhibidores , Neovascularización Patológica/inmunología , Factor C de Crecimiento Endotelial Vascular/genética , Factor C de Crecimiento Endotelial Vascular/farmacología , Factor D de Crecimiento Endotelial Vascular/genética , Factor D de Crecimiento Endotelial Vascular/farmacología
8.
Pathol Oncol Res ; 14(1): 93-6, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18350376

RESUMEN

The etiological role of human papillomavirus (HPV) in a number of squamous malignant tumors is well known. Squamous cell carcinoma (SCC) of colon is a rare disease with uncertain etiology. Our objective was to detect possible HPV infection in a colon SCC patient. The 94-year-old female patient was operated due to colon tumor causing passage disturbances. Histology confirmed SCC. Tumor tissue and the removed lymph nodes were examined with polymerase chain reaction and Southern blot hybridization techniques. Of HPV types most often occurring in malignant tumors (16, 18) the presence of HPV type 16 could be confirmed in the primary tumor and in four out of the nine surrounding lymph nodes, of which two were metastatic. HPV-16 infection could be detected in an SCC patient in the primary tumor and in surrounding lymph nodes. According to our knowledge, no similar study has been published yet.


Asunto(s)
Carcinoma de Células Escamosas/virología , Neoplasias del Colon/virología , Papillomavirus Humano 16/aislamiento & purificación , Metástasis Linfática/diagnóstico , Infecciones por Papillomavirus/virología , Anciano de 80 o más Años , Southern Blotting/métodos , Carcinoma de Células Escamosas/secundario , Carcinoma de Células Escamosas/cirugía , Neoplasias del Colon/cirugía , Femenino , Papillomavirus Humano 16/genética , Humanos , Reacción en Cadena de la Polimerasa/métodos
9.
Magy Seb ; 61(2): 84-7, 2008 Apr.
Artículo en Húngaro | MEDLINE | ID: mdl-18426713

RESUMEN

Mesenteric panniculitis can develop in every patient after abdominal surgery. The clinical and pathological signs are usually vague, so different therapeutic approaches are recommended at various stages of the disease. While some authors suggest that these stages are different manifestations of the the same disease, others claim that the various stages represent the progression of a single entity. We report a case of a 65 year-old male patient with mesenteric panniculitis and fibrosis, which developed after laparoscopic sigmoid resection first, and required a Hartmann's procedure finally. The disease developed once again after the elective reconstruction of the colon. This time surgical intervention was not possible and he was treated conservatively with intravenous steroids, antibiotics, parenteral nutrition and continuous nasogastric tube. The patient gradually recovered in three weeks time. We report this successful treatment, and review the relevant literature.


Asunto(s)
Colectomía/efectos adversos , Colon Sigmoide/cirugía , Paniculitis Peritoneal/etiología , Paniculitis Peritoneal/terapia , Anciano , Colectomía/métodos , Necrosis Grasa/etiología , Fibrosis/etiología , Humanos , Laparoscopía/efectos adversos , Masculino , Paniculitis Peritoneal/patología , Paniculitis Peritoneal/cirugía , Recurrencia , Retratamiento , Resultado del Tratamiento
10.
Cancer Res ; 65(16): 7186-93, 2005 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-16103069

RESUMEN

Recombinant human erythropoietin (rHuEPO) is widely used for correction of hemoglobin level in cancer patients. However, apart from hematopoiesis, rHuEPO reportedly has an effect on endothelial cells. We describe here how rHuEPOalpha can modulate tumor vasculature in human squamous cell (A431) and colorectal carcinoma (HT25) xenograft models. In vivo rHuEPO treatment of xenografts at human-equivalent dose significantly increased the proliferation index of the tumor-associated endothelial cells and the size of CD31-positive intratumoral blood vessels, whereas the pericyte coverage became fragmented. Moreover, rHuEPO administration resulted in decreased expression of vascular endothelial growth factor both by cancer cells and tumor stroma, measured by quantitative PCR. Due to the morphologic alterations in tumoral microvessels, DNA-binding agents (Hoechst and Doxorubicin) labeled significantly larger areas in the tumor mass. Furthermore, rHuEPO treatment led to a significantly improved efficacy of 5-fluorouracil (5-FU) chemotherapy in the case of both tumor xenografts. Meanwhile, rHuEPO had no effect on the in vitro proliferation of erythropoietin receptor-positive tumor cells, and did not interfere with the effects of 5-FU either. These data reveal a new effect of rHuEPO administration: remodeling tumoral microvessels, suppressing vascular endothelial growth factor expression, thereby augmenting antitumor effects of a cancer drug, 5-FU, even in erythropoietin receptor-positive human cancer xenografts.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Carcinoma de Células Escamosas/irrigación sanguínea , Carcinoma de Células Escamosas/tratamiento farmacológico , Neoplasias Colorrectales/irrigación sanguínea , Neoplasias Colorrectales/tratamiento farmacológico , Eritropoyetina/farmacología , Animales , Carcinoma de Células Escamosas/metabolismo , Línea Celular Tumoral , Neoplasias Colorrectales/metabolismo , Sinergismo Farmacológico , Eritropoyetina/administración & dosificación , Femenino , Fluorouracilo/administración & dosificación , Humanos , Ratones , Ratones SCID , Neovascularización Patológica/tratamiento farmacológico , Pericitos/efectos de los fármacos , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Receptores de Eritropoyetina/biosíntesis , Receptores de Eritropoyetina/genética , Proteínas Recombinantes , Ensayos Antitumor por Modelo de Xenoinjerto
11.
Clin Exp Metastasis ; 22(1): 69-76, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16132580

RESUMEN

Use of heparin derivatives in several cancer types revealed that anticoagulant therapies have a beneficiary side effect: delay of tumor progression. Since there are no data on human melanoma, we have analyzed the effect of heparins in preclinical models. Neither unfractionated heparin (UFH), nor its low molecular weight derivative (LMWH) influenced in vitro or in vivo growth of HT168-M1 human melanoma cells. However, heparins significantly inhibited lung colony formation and liver metastasis development in the concentration range of 20-200 IU/kg, whereas recombinant hirudin was ineffective. The antimetastatic effect was due to an early (5-60 min) inhibition of tumor cell arrest in the lung microvasculature. Analysis of the molecular mechanism of the antimetastatic effect of heparins indicated a specific inhibition of tumor cell migration and matrix invasion. The presented experimental data suggest that heparins have specific antimetastatic effect in the case of human melanoma, which is independent from the coagulation cascade.


Asunto(s)
Anticoagulantes/uso terapéutico , Heparina/uso terapéutico , Neoplasias Hepáticas/prevención & control , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/prevención & control , Neoplasias Pulmonares/secundario , Melanoma/tratamiento farmacológico , Melanoma/patología , Animales , Anticoagulantes/farmacología , Capilares/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Proteínas de la Matriz Extracelular/metabolismo , Femenino , Hemostasis/efectos de los fármacos , Heparina/farmacología , Heparina de Bajo-Peso-Molecular/farmacología , Heparina de Bajo-Peso-Molecular/uso terapéutico , Humanos , Neoplasias Hepáticas/irrigación sanguínea , Neoplasias Pulmonares/irrigación sanguínea , Ratones , Ratones SCID , Trasplante de Neoplasias , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Células Tumorales Cultivadas
12.
Magy Onkol ; 48(3): 235-41, 2004.
Artículo en Húngaro | MEDLINE | ID: mdl-15520874

RESUMEN

Heparin treatment, at human equivalent doses, modulates coagulation parameters in mice similarly to the human situation. Heparins were tested in various melanoma metastasis models for their antimetastatic activity. Heparins were active against melanoma metastasis without influencing the primary tumor. Tumor cell-induced platelet aggregation was not the primary target of heparins, since melanoma cells were not active in this respect. Our results support the notion that heparins have antimetastatic activity.


Asunto(s)
Antineoplásicos/farmacología , Heparina/farmacología , Melanoma Experimental/prevención & control , Animales , Adhesión Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Humanos , Melanoma Experimental/secundario , Ratones
13.
J Mol Histol ; 42(5): 427-42, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21847509

RESUMEN

The small GTPase RhoA and its downstream effectors, the Rho-associated kinase (Rho-kinase) family, are known to regulate cell morphology, motility, and tumor progression via the regulation of actin cytoskeleton rearrangement. In the present study, we evaluated the role of Rho-kinase in the intracellular endocytic trafficking of ligand-induced phosphorylated epidermal growth factor receptor (pEGFR). We investigated the time course of the internalization fate of EGF-induced pEGFR via the early/late endocytic pathway in human fibrosarcoma cell line HT1080 cells using Y-27632, a selective Rho-kinase inhibitor. We found, using confocal immunofluorescence microscopy and Western blot analysis, a large accumulation of pEGFR in the nuclei of HT1080 cells. In contrast, we observed decreased amounts of the pEGFR-positive staining in the nuclei along with an accumulation of cytosolic pEGFR staining when the cells were incubated for 15-30 min in the presence of Y-27632, implying that an aberrant endocytic trafficking mechanism of pEGFR occurs in HT1080 cells whereby pEGFR might be selectively translocated into the nucleus. Moreover, we demonstrated that after 15-min of stimulation with Texas Red-EGF, increasing numbers of pEGFR-positive staining that had colocalized with Texas Red-EGF-positive punctate staining were seen in the cytoplasm of HT1080 cells but after 30-min of stimulation, most of this staining had disappeared from the cytoplasm and a large accumulation of pEGFR-positive staining appeared in the nucleus. Thus, nuclear accumulation of pEGFR appears to occur in an EGF-dependent manner. In contrast, such nuclear pEGFR-positive staining was not seen in the Y-27632-treated cells. Furthermore, silencing of RhoA or Rho-kinases I/II by sequence specific siRNAs considerably inhibited the EGF-dependent nuclear accumulation of pEGFR. Collectively, these results provide the first evidence that Rho-kinase signaling pathway plays a suppressive role in the intracellular vesicle trafficking of pEGFR via the endocytic pathway and that an increased Rho-kinase activity leads to the attenuation of the normal endocytic vesicular traffic of pEGFR via the early/late endocytic pathway, instead causing pEGFR to be trafficked out of the endocytic vesicles into the nucleus.


Asunto(s)
Endocitosis , Receptores ErbB/metabolismo , Fibrosarcoma/enzimología , Fibrosarcoma/patología , Transducción de Señal , Quinasas Asociadas a rho/metabolismo , Citoesqueleto de Actina/efectos de los fármacos , Citoesqueleto de Actina/metabolismo , Amidas/farmacología , Western Blotting , Línea Celular Tumoral , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Endocitosis/efectos de los fármacos , Factor de Crecimiento Epidérmico/farmacología , Silenciador del Gen/efectos de los fármacos , Humanos , Ligandos , Fosforilación/efectos de los fármacos , Transporte de Proteínas/efectos de los fármacos , Piridinas/farmacología , ARN Interferente Pequeño/metabolismo , Transducción de Señal/efectos de los fármacos , Proteína de Unión al GTP rac1/antagonistas & inhibidores , Proteína de Unión al GTP rac1/metabolismo , Quinasas Asociadas a rho/antagonistas & inhibidores
14.
Thromb Haemost ; 102(6): 1265-73, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19967160

RESUMEN

Heparin and its derivatives have been shown to inhibit angiogenesis and metastasis formation. Accordingly, we investigated the effect of heparin fragments containing 4 to 22 monomers on human melanoma cell proliferation, migration and invasion in vitro as well as on the in vivo metastatic potential in a SCID mouse model. Only oligosaccharide dp18 had significant inhibitory effect on cell proliferation. In contrast, cell migration was inhibited by all oligosaccharides studied except dp8 and dp22. Anti-CD44v3 antibody stimulated cell migration and invasion, and this effect could be attenuated by oligosaccharides dp4 and dp18. These fragments also inhibited the catalytic activity of myosin light chain phosphatase as well. Moreover, oligosaccharides dp4 and dp18 reduced the number of lung colonies formed in SCID mice intravenously injected with human melanoma cells, while dp22 proved to be ineffective in this respect. These studies revealed that fragments of heparin have an antimigratory and antimetastatic potential. These fragments lack the haemostatic effect of heparin, suggesting that they are potential specific antimetastatic agents in anticancer therapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Heparina de Bajo-Peso-Molecular/uso terapéutico , Melanoma Experimental/tratamiento farmacológico , Oligosacáridos/uso terapéutico , Animales , Antineoplásicos/química , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Heparina de Bajo-Peso-Molecular/química , Humanos , Receptores de Hialuranos/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/secundario , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Melanoma Experimental/secundario , Ratones , Ratones SCID , Invasividad Neoplásica , Trasplante de Neoplasias , Oligosacáridos/química , Proteína Fosfatasa 1/antagonistas & inhibidores , Trasplante Heterólogo
15.
Strahlenther Onkol ; 184(1): 1-7, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18188516

RESUMEN

BACKGROUND AND PURPOSE: Tumor-induced anemia often occurs in cancer patients, and is corrected by recombinant human erythropoietins (rHuEPOs). Recent studies indicated that, besides erythroid progenitor cells, tumor and endothelial cells express erythropoietin receptor (EPOR) as well; therefore, rHuEPO may affect their functions. Here, the effect of rHuEPOalpha on irradiation in EPOR-positive human squamous cell carcinoma xenograft was tested. MATERIAL AND METHODS: A431 tumor-bearing SCID mice were treated from the tumor implantation with rHuEPOalpha at human-equivalent dose. Xenografts were irradiated (5 Gy) on day 14, and the final tumor mass was measured on day 22. The systemic effects of rHuEPOalpha on the hemoglobin level, on tumor-associated blood vessels and on hypoxia-inducible factor-(HIF-)1alpha expression of the tumor xenografts were monitored. The proliferation, apoptosis and clonogenic capacity of A431 cancer cells treated with rHuEPOalpha and irradiation were also tested in vitro. RESULTS: In vitro, rHuEPOalpha treatment alone did not modify the proliferation of EPOR-positive A431 tumor cells but enhanced the effect of irradiation on proliferation, apoptosis and clonogenic capacity. In vivo, rHuEPOalpha administration compensated the tumor-induced anemia in SCID mice and decreased tumoral HIF-1alpha expression but had no effect on tumor growth. At the same time rHuEPOalpha treatment significantly increased the efficacy of radiotherapy in vivo (tumor weight of 23.9 +/- 4.7 mg and 34.9 +/- 4.6 mg, respectively), mediated by increased tumoral blood vessel destruction. CONCLUSION: rHuEPOalpha treatment may modulate the efficacy of cancer radiotherapy not only by reducing systemic hypoxia and tumoral HIF-1alpha expression, but also by destroying tumoral vessels.


Asunto(s)
Apoptosis/efectos de la radiación , Carcinoma de Células Escamosas/radioterapia , División Celular/efectos de la radiación , Eritropoyetina/farmacología , Fármacos Sensibilizantes a Radiaciones/farmacología , Neoplasias de los Tejidos Blandos/radioterapia , Ensayo de Tumor de Célula Madre , Animales , Apoptosis/efectos de los fármacos , Carcinoma de Células Escamosas/patología , División Celular/efectos de los fármacos , Línea Celular Tumoral , Femenino , Humanos , Técnicas In Vitro , Ratones , Ratones SCID , Trasplante de Neoplasias , Proteínas Recombinantes , Neoplasias de los Tejidos Blandos/patología , Trasplante Heterólogo
16.
Histochem Cell Biol ; 127(5): 541-53, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17361439

RESUMEN

The drug gefitinib (Iressa), which is a specific inhibitor of EGFR tyrosine kinase, has been shown to suppress the activation of EGFR signaling for survival and proliferation in non-small cell lung cancer (NSCLC) cell lines. A recent study demonstrated rapid down-regulation of ligand-induced EGFR in a gefitinib-sensitive cell line and inefficient down-regulation of EGFR in a gefitinib-resistant cell line in the exponential phase of growth; this implies that each cell type employs a different unknown down-regulation mechanism occurs. However, the mechanism of drug sensitivity to gefitinib remains unclear. In this study, to further substantiate the effect of gefitinib on the EGFR down-regulation pathway and to understand the detailed internalization mechanism of gefitinib-sensitive PC9 and gefitinib-resistant QG56 cell lines, we examined the internalization of Texas red-EGF in the absence or presence of gefitinib in both cell lines. The distribution of internalized Texas red-EGF, early endosomes, and late endosomes/lysosomes was then assessed by confocal immunofluorescence microscopy. Here, we provide novel evidence that efficient endocytosis of EGF-EGFR occurs via the endocytic pathway in the PC9 cells, because the internalized Texas red-EGF-positive small punctate vesicles were transported to the late endosomes/lysosomes and then degraded within the lysosomes after 60 min of internalization. Additionally, gefitinib exerted a strong inhibitory effect on the endocytosis of EGFR in PC9 cells, and the internalization rate of EGFR from the plasma membrane via the early endosomes to the late endosomes/lysosomes was considerably delayed. This indicates that gefitinib efficiently suppresses ligand-stimulated endocytosis of EGFR via the early/late endocytic pathway in PC9 cells. In contrast, the internalization rate of ligand-induced EGFR was not significantly changed by gefitinib in QG56 cells because even in the absence of gefitinib, internalized EGFR accumulation was noted in the early and late endosomes after 60 min of internalization instead of its delivery to the lysosomes in QG56 cells. This suggests that the endocytic machinery of EGFR might be basically impaired at the level of the early/late endosomes. Taken together, this is the first report demonstrating that the suppressive effect of gefitinib on the endocytosis of EGFR is much stronger with PC9 cells than QG56 cells. Thus, impairment in some steps of the EGF-EGFR traffic out of early endosomes toward the late endosomes/lysosomes might confer gefitinib-resistance in NSCLC cell lines.


Asunto(s)
Endocitosis/efectos de los fármacos , Receptores ErbB/metabolismo , Quinazolinas/farmacología , Transducción de Señal/efectos de los fármacos , Antineoplásicos/farmacología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Catepsina D/metabolismo , Línea Celular Tumoral , Membrana Celular/química , Membrana Celular/metabolismo , Resistencia a Antineoplásicos , Endocitosis/fisiología , Endosomas/química , Endosomas/metabolismo , Factor de Crecimiento Epidérmico/metabolismo , Receptores ErbB/análisis , Receptores ErbB/antagonistas & inhibidores , Gefitinib , Humanos , Proteínas de Membrana de los Lisosomas/análisis , Lisosomas/metabolismo , Microscopía Fluorescente , Transporte de Proteínas/efectos de los fármacos , Proteínas Qa-SNARE/análisis , Receptores Depuradores/análisis , Transferrina/metabolismo
17.
Histochem Cell Biol ; 126(5): 627-38, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16763828

RESUMEN

We have previously shown that overexpression of LIM kinase1 (LIMK1) resulted in a marked retardation of the internalization of the receptor-mediated endocytic tracer, Texas red-labeled epidermal growth factor (EGF) in low-invasive human breast cancer cell MCF-7. We thereby postulate that LIMK1 signaling plays an important role in the regulation of ligand-induced endocytosis of EGF receptor (EGFR) in tumor cells by reorganizing and influencing actin-filament dynamics. In the present study, we further assessed the effect of wild-type LIMK1, a kinase-deficient dominant negative mutant of LIMK1 (DN-LIMK1) and an active, unphosphorylatable cofilin mutant (S3A cofilin) on internalization of EGF-EGFR in MDA-MB-231, a highly invasive human breast cancer cell line. We demonstrate here that a marked delay in the receptor-mediated internalization of Texas red-labeled EGF was observed in the wild-type LIMK1 transfectants, and that most of the internalized EGF staining were accumulated within transferrin receptor-positive early endosomes even after 30 min internalization. In contrast, the expression of dominant-negative LIMK1 mutant rescued the efficient endocytosis of Texas red-EGF, and large amounts of Texas red-EGF staining already reached LIMPII-positive late endosomes/lysosomal vacuoles after 15 min internalization. We further analyzed the effect of S3A cofilin mutant on EGFR trafficking, and found an efficient delivery of Texas red-EGF into late endosomes/lysosomes at 15-30 min after internalization. Taken together, our novel findings presented in this paper implicate that LIMK1 signaling indeed plays a pivotal role in the regulation of EGFR trafficking through the endocytic pathway in invasive tumor cells.


Asunto(s)
Factores Despolimerizantes de la Actina/fisiología , Neoplasias de la Mama/metabolismo , Endocitosis/fisiología , Receptores ErbB/metabolismo , Proteínas Quinasas/fisiología , Factores Despolimerizantes de la Actina/genética , Catepsina D/metabolismo , Femenino , Humanos , Immunoblotting , Quinasas Lim , Proteínas de Membrana de los Lisosomas/metabolismo , Transporte de Proteínas , Receptores Depuradores/metabolismo , Transducción de Señal , Transfección , Células Tumorales Cultivadas
18.
Oncology ; 69(3): 185-201, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16138000

RESUMEN

Stem cell mimicry of cancer cells has been known for a long time and is considered to be responsible for ectopic gene expressions. The stem cell characteristics of tumor cells are shown to be involved in epithelial-mesenchymal transition and in the phenomenon of vascular mimicry. Certain cancer types acquire a geno-phenotype closely resembling the platelets and express several megakaryocytic genes (adhesion receptors alpha IIb beta 3, thrombin receptor and PECAM/CD 31 and/or platelet-type 12-LOX) able to activate the coagulation cascade or the platelets themselves. Here we define these potentials as platelet mimicry of cancer cells typical of pancreatic, breast, prostate, colorectal and urogenital cancers and melanoma. Data all support that platelet mimicry of certain cancer types is an important factor in their hematogenous dissemination and provides an attractive therapeutic target. Besides the long-available preclinical data, clinical trials have only recently provided evidence that targeting platelet mimicry of cancers is an efficient way to prevent tumor progression. The systematic discovery of the markers of platelet mimicry in various cancer types and their molecular targeting may provide new supportive therapeutic modalities for the management of the progressing disease.


Asunto(s)
Plaquetas/metabolismo , Neoplasias/metabolismo , Células Neoplásicas Circulantes/metabolismo , Células Madre Neoplásicas/metabolismo , Animales , Trastornos de la Coagulación Sanguínea/tratamiento farmacológico , Trastornos de la Coagulación Sanguínea/etiología , Regulación Neoplásica de la Expresión Génica , Genotipo , Humanos , Megacariocitos/metabolismo , Metástasis de la Neoplasia/genética , Neoplasias/complicaciones , Neoplasias/genética , Neoplasias/patología , Fenotipo , Inhibidores de Agregación Plaquetaria/uso terapéutico
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