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1.
Tech Coloproctol ; 27(11): 1065-1071, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37642739

RESUMEN

PURPOSE: The safety and feasibility of minimally invasive surgery (MIS) in the setting of colorectal cancer emergencies have been debated. We sought to compare postoperative outcomes of MIS with open techniques in the setting of colorectal cancer emergencies from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. METHODS: We included patients undergoing colectomy for colorectal cancer emergency between 2012 and 2019 "2012-2019" from the ACS-NSQIP dataset. We compared short-term morbidity, mortality, short-term oncological outcomes, and secondary outcomes for MIS vs open colectomies using propensity score matching. We then evaluated the trends of MIS versus open colectomies using linear regression analysis. RESULTS: We examined a total of 5544 patients (open n = 4070; MIS n = 1474) and included 1352 patients for our postoperative outcome analyses after propensity score matching 1:1 (open n = 676; MIS n = 676). Within the matched cohort, mortality was significantly higher in the open group (open 6.95% vs MIS 3.99%, OR 1.8, p = 0.023). Anastomotic leak rates were comparable between the  two groups (open 4.46% vs MIS 4.02%, OR 1.12, p = 0.787). Pulmonary complications were significantly higher after open surgery (open 10.06% vs MIS 4.73%, OR 2.25, p < 0.001). Rates of ileus were significantly higher amongst open patients (open 29.08% vs MIS 19.94%, p < 0.001). Patients stayed on average 1 day longer in the hospital after open surgery (p < 0.001). Rates of MIS for early tumors (N0 and T1/T2, n = 289) did not significantly change over 7 years (p = 0.597, rate = - 0.065%/year); however, utilization of MIS for late tumors (N1 or T3/T4, n = 4359) increased by 2.06% per year (p < 0.001). CONCLUSIONS: This study demonstrates that MIS was associated with superior postoperative outcomes compared to open surgery without compromising oncological outcomes in patients undergoing emergency colectomy for colon cancer. Within the matched cohort, MIS was associated with lower rates of mortality, pulmonary complications, ileus, and shorter postoperative length of stay.

2.
Aging Clin Exp Res ; 32(2): 265-273, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30982218

RESUMEN

BACKGROUND: The enhanced recovery after surgery (ERAS) is nowadays a widely accepted multimodal programme of care in colorectal surgery, but still there is some reluctance in its application to very elderly patients. AIM: The aim of this study is to investigate short-term outcomes of laparoscopic resection for colorectal cancer in octogenarian patients within the ERAS programme. METHODS: Data on 162 consecutive patients aged ≥ 80 years receiving elective minimally invasive colorectal resections within ERAS programme were collected in a multicentre, retrospective database in the period 2008-2017 in Italy. Univariate and multivariate analyses were performed to assess possible risk factors for poor clinical outcomes. RESULTS: The postoperative minor morbidity rate (Clavien-Dindo 1 and 2) was 25.9%. The incidence of postoperative major morbidity rate (severe medical and surgical complications defined as Clavien-Dindo 3 and 4) accounted 6.1% and only 1.8% had an anastomotic leakage. Reoperation rate was 5.5%, perioperative 30-day mortality was 1.8%, and 30-day readmission rate was 6.8%. On average, patients were released after 6 days. A univariate analysis showed that possible risk factors for severe medical complications were: low preoperative albumin level, high Charlson Age Comorbidity Index Score and number of days in the intensive care unit (ICU); risk factors for severe surgical complications were: low preoperative albumin level; risk factors for late hospital discharge were: multivisceral resections, number of days in ICU and body mass index (BMI) > 25 kg/m2. The multivariate analysis confirmed a low level of preoperative albumin and a longer ICU stay as independent risk factors for both postoperative severe surgical complications and late hospital discharge. DISCUSSION: The minimal invasive nature of the laparoscopic approach together with a multimodal analgesia therapy, the early resumption to oral diet and mobilisation could minimize the surgical stress and play an essential role in order to reduce medical morbidity in high-risk patients. CONCLUSION: Colorectal surgery within ERAS programme in octogenarians is a safe and flexible treatment in high-volume centres.


Asunto(s)
Neoplasias Colorrectales/cirugía , Procedimientos Quirúrgicos del Sistema Digestivo , Anciano de 80 o más Años , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Procedimientos Quirúrgicos Electivos/efectos adversos , Recuperación Mejorada Después de la Cirugía , Estudios de Factibilidad , Femenino , Humanos , Italia , Tiempo de Internación , Masculino , Procedimientos Quirúrgicos Mínimamente Invasivos/efectos adversos , Complicaciones Posoperatorias/etiología , Periodo Posoperatorio , Reoperación , Estudios Retrospectivos , Factores de Riesgo
3.
G Chir ; 38(3): 117-123, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29205140

RESUMEN

BACKGROUND: Autologous fat transplantation is used after breast reconstruction to improve the breast profile. There are a variety of different methods used for fat harvesting, preparation, and reinjection. This study describes the specific techniques we used in this series of autologous fat transplantations in breast reconstruction patients and reports their outcomes compared with other studies in the literature. PATIENTS AND METHODS: At the University Hospital of Parma between May 2012 and December 2016, we performed 53 autologous fat transplantations for secondary breast reconstruction patients with an average age of 49 years (range: 34-65 y). A tumescent fluid (NaCl, epinephrine, and a local anaesthetic) was injected, and the lipoaspirate was harvested using a closed aspiration-injection system connected to a 50 ml syringe, a 4 mm infiltration cannula, and a -650 mmHg vacuum. The average amount of lipoaspirate obtained was 100 ml (range: 50-200 ml). Centrifugation of the lipoaspirate (3000 rpm for 3 min) was performed to isolate the adipose tissue (average amount obtained, 80 ml; range: 30-180 ml). Under local anaesthesia, the retrograde injection of thin layers of fat graft in multiple tunnels was performed in the subcutaneous and/or subglandular planes. RESULTS: Average follow-up was six months. Comparable to other studies, our complication rate was 7.4% (n = 4/53) and included cyst formation at the injection site (n = 1/53) and hematoma at the donor site (n = 3/53). Repeat fat grafting was performed in 28.3% of patients (n = 15/53) due to fat graft resorption. CONCLUSIONS: Autologous fat transplantation is a useful procedure for correcting irregularities in the breast contour in secondary breast reconstruction.


Asunto(s)
Tejido Adiposo/trasplante , Neoplasias de la Mama/cirugía , Mamoplastia/métodos , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Trasplante Autólogo/métodos , Resultado del Tratamiento
7.
Eur Rev Med Pharmacol Sci ; 15(2): 205-10, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21434488

RESUMEN

OBJECTIVES: The analgesic efficacy of two fixed combinations of tramadol/paracetamol (TP 37.5/325 mg) and codeine/paracetamol (CP 30/500 mg) was compared in 122 patients undergoing one-day surgical procedures (hallux valgus, haemorrhoidectomy, varicectomy and inguinal hernia repair), randomly treated with TP 37.5/325 mg or CP 30/500 mg one tablet after surgery ended, followed by one tablet four times daily for 48 hours. METHODS: Pain was assessed by a Verbal Rating Scale (VRS). Whenever the VRS score was > or = 3, the patient was given a "rescue medication" (tramadol 50 mg s.c.). The quality of life (time to return to normal daily activities, nightly rest, appetite, mood, deambulation, and self-care) was assessed in the postoperative period. Patients were asked to give their judgment on the surgical procedure and postoperative outcome. RESULTS: The results indicate that TP 37.5/325 mg was superior to CP 30/500 mg in terms of higher analgesic efficacy (VSR at 24 hours: CP 30/500, 2.52 +/- 0.86 vs. TP 37.5/325, 1.40 +/- 0.76; p < 0.001), less patients reporting adverse events (CP 30/500: 62% vs. TP 37.5/325: 36%; p < 0.01), less patients requiring rescue medications (CP 30/500: 18.2% vs. TP 37.5/325: 5.5%; p < 0.01), and more favorable judgment (scored "excellent" by 16% and 54.5% of CP 30/500 or TP 37.5/325-treated patients, respectively; p < 0.001). CONCLUSIONS: We conclude that a fixed association of tramadol/paracetamol is a valuable and safe tool for pain management in day hospital surgery, especially whenever any effort is done to reduce the time for hospitalization.


Asunto(s)
Acetaminofén/administración & dosificación , Procedimientos Quirúrgicos Ambulatorios , Codeína/administración & dosificación , Dolor Postoperatorio/tratamiento farmacológico , Tramadol/administración & dosificación , Acetaminofén/uso terapéutico , Adulto , Anciano , Analgesia , Codeína/uso terapéutico , Quimioterapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tramadol/uso terapéutico
8.
G Chir ; 32(8-9): 372-3, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22018259

RESUMEN

We report a rare case of a hepatic carcinosarcoma with rabdomyosarcomatous differentiation in its sarcomatous component. A 71-year old Caucasian female patient underwent a liver resection for a 4-cm lesion developed on an underlying HCV-related cirrhosis. Post-operative course was uneventful and the patient was discharged 5 days after surgery. At pathology, the tumor presented the features of hepatocellular carcinoma and rhabdomyosarcoma Three months later the patient experienced a liver recurrence, dying 2 months later for systemic disease. The reported case presents several peculiarities, i.e. the female gender, the HCV-related cirrhotic status, and the European origin of the patient. However, the outcome of our case confirms that this neoplasm pursues a highly aggressive course with poor prognosis.


Asunto(s)
Carcinosarcoma/diagnóstico , Neoplasias Hepáticas/diagnóstico , Anciano , Carcinosarcoma/patología , Carcinosarcoma/cirugía , Resultado Fatal , Femenino , Hepatectomía/métodos , Hepatitis C Crónica/complicaciones , Humanos , Hallazgos Incidentales , Italia , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Recurrencia Local de Neoplasia
9.
Science ; 267(5196): 381-3, 1995 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-7824936

RESUMEN

Multiple endocrine neoplasia types 2A and 2B (MEN2A and MEN2B) and familial medullary thyroid carcinoma are dominantly inherited cancer syndromes. All three syndromes are associated with mutations in RET, which encodes a receptor-like tyrosine kinase. The altered RET alleles were shown to be transforming genes in NIH 3T3 cells as a consequence of constitutive activation of the RET kinase. The MEN2A mutation resulted in RET dimerization at steady state, whereas the MEN2B mutation altered RET catalytic properties both quantitatively and qualitatively. Oncogenic conversion of RET in these neoplastic syndromes establishes germline transmission of dominant transforming genes in human cancer.


Asunto(s)
Transformación Celular Neoplásica/genética , Proteínas de Drosophila , Neoplasia Endocrina Múltiple Tipo 2a/genética , Neoplasia Endocrina Múltiple Tipo 2b/genética , Proteínas Proto-Oncogénicas/genética , Proto-Oncogenes , Proteínas Tirosina Quinasas Receptoras/genética , Células 3T3 , Alelos , Animales , Vectores Genéticos , Humanos , Ratones , Mutación , Fosforilación , Proteínas Proto-Oncogénicas/química , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-ret , Proteínas Tirosina Quinasas Receptoras/química , Proteínas Tirosina Quinasas Receptoras/metabolismo , Especificidad por Sustrato , Transfección , Células Tumorales Cultivadas
10.
Oncogene ; 26(42): 6167-75, 2007 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-17420723

RESUMEN

H4(D10S170) gene has been identified upon its frequent rearrangement with RET in papillary thyroid tumours (RET/PTC1). The kinase ataxia telangectasia mutated (ATM) phosphorylates a limited number of downstream protein targets in response to DNA damage. We investigated the potential role of H4(D10S170) in DNA damage signaling pathways. We found that in cells treated with etoposide or ionizing radiation (IR), H4(D10S170) underwent ATM-mediated phosphorylation at Thr 434, stabilizing nuclear H4. In ataxia telangectasia cells (A-T), endogenous H4(D10S170) was localized to cytoplasm and was excluded from the nucleus. Moreover, H4(D10S170) was not phosphorylated in ATM-deficient lymphoblasts after ionizing irradiation. Inhibition of ATM kinase interfered with H4(D10S170) apoptotic activity, and expression of H4 with threonine 434 mutated in Alanine, H4(T434A), protected the cells from genotoxic stress-induced apoptosis. Most importantly, after exposure to IR we found that silencing of H4(D10S170) in mammalian cells increased cell survival, as shown by clonogenic assay, allows for DNA synthesis as evaluated by bromodeoxyuridine incorporation and permits cells to progress into mitosis as demonstrated by phosphorylation on Histone H3. Our results suggest that H4(D10S170) is involved in cellular response to DNA damage ATM-mediated, and that the impairment of H4(D10S170) gene function might have a role in thyroid carcinogenesis.


Asunto(s)
Proteínas de Ciclo Celular/fisiología , Proteínas del Citoesqueleto/metabolismo , Daño del ADN/genética , Proteínas de Unión al ADN/fisiología , Proteínas Serina-Treonina Quinasas/fisiología , Proteínas Supresoras de Tumor/fisiología , Secuencia de Aminoácidos , Proteínas de la Ataxia Telangiectasia Mutada , Línea Celular Tumoral , Proteínas del Citoesqueleto/antagonistas & inhibidores , Silenciador del Gen , Células HeLa , Humanos , Datos de Secuencia Molecular , Fosforilación , Neoplasias de la Tiroides/genética
11.
Oncogene ; 25(54): 7117-30, 2006 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-16751808

RESUMEN

Oncogenic Ras interferes with adhesive functions of epithelial cells, but requires tumor growth factor beta (TGFbeta) signaling to cause epithelial-mesenchymal transition (EMT) and tumor progression in model systems. To investigate the mechanisms by which Ras and TGFbeta pathways cooperate in EMT induction, we introduced a tamoxifen-inducible version of Raf-1 (RafER) into fully polarized, mammary epithelial cells (EpH4). EMT characterized by loss of E-cadherin expression and upregulation of invasiveness-promoting genes was induced by TGFbeta plus 4-hydroxytamoxifen (4HT) activation of RafER. Downregulation of E-cadherin by RafER plus TGFbeta was detectable in total cell lysates after 48 h and much earlier in detergent-insoluble fractions of E-cadherin. Both pathways cooperated to strongly enhance endocytosis of E-cadherin, mainly via the clathrin-dependent route. Pulse-chase experiments showed decreased E-cadherin protein stability in cells stimulated with TGFbeta and 4HT and increased E-cadherin half-life in the presence of monensin. Monensin and chloroquine prevented E-cadherin degradation to different extent, but only monensin effectively blocked the loss of E-cadherin from the junctional complexes. Both lysosome inhibitors caused accumulation of E-cadherin vesicles, some of which were positive for Cathepsin D and lysosome-associated membrane protein 1 (LAMP-1). In addition, TGFbeta and mitogen-activated protein kinase hyperactivation synergistically induced E-cadherin ubiquitination, suggesting that the cooperation of Raf and TGFbeta favors lysosomal degradation of E-cadherin instead of its recycling. Our data indicate that early stages of EMT involve cooperative, post-translational downregulation of E-cadherin, whereas loss of E-cadherin via transcriptional repression is a late event in EMT.


Asunto(s)
Cadherinas/metabolismo , Transformación Celular Neoplásica , Células Epiteliales/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Quinasas raf/metabolismo , Animales , Northern Blotting , Western Blotting , Línea Celular Tumoral , Regulación hacia Abajo , Endocitosis , Células Epiteliales/patología , Técnica del Anticuerpo Fluorescente , Inmunoprecipitación , Lisosomas/metabolismo , Ratones , Microscopía Confocal , Procesamiento Proteico-Postraduccional , Proteínas Recombinantes de Fusión
12.
J Clin Invest ; 89(5): 1517-22, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1569189

RESUMEN

We have recently reported the activation of a new oncogene in human papillary thyroid carcinomas. This oncogene, papillary thyroid carcinoma (PTC), is a novel rearranged version of the ret tyrosine-kinase protooncogene. Thyroid neoplasms include a broad spectrum of malignant tumors, ranging from well-differentiated tumors to undifferentiated anaplastic carcinomas. To determine the frequency of ret oncogene activation, we analyzed 286 cases of human thyroid tumors of diverse histologic types. We found the presence of an activated form of the ret oncogene in 33 (19%) of 177 papillary carcinomas. By contrast, none of the other 109 thyroid tumors, which included 37 follicular, 15 anaplastic, and 18 medullary carcinomas, and 34 benign lesions, showed ret activation.


Asunto(s)
Carcinoma Papilar/genética , Proteínas de Drosophila , Oncogenes , Proteínas Proto-Oncogénicas/genética , Proteínas Tirosina Quinasas Receptoras , Neoplasias de la Tiroides/genética , Secuencia de Bases , Southern Blotting , Transformación Celular Neoplásica/genética , ADN de Neoplasias/genética , Expresión Génica , Reordenamiento Génico , Humanos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Proteínas Proto-Oncogénicas c-ret , ARN Mensajero/genética , ARN Neoplásico/genética , Mapeo Restrictivo , Neoplasias de la Tiroides/patología , Transfección
13.
Mol Cell Biol ; 8(5): 2261-6, 1988 May.
Artículo en Inglés | MEDLINE | ID: mdl-2838744

RESUMEN

Two rat thyroid epithelial differentiated cell lines, PC Cl 3 and PC myc, were infected with the polyoma murine leukemia virus (PyMLV) carrying the Middle-T-antigen gene of polyomavirus. After infection, both cell lines acquired the typical markers of neoplastic transformation; however, the PC myc cells showed a greater malignant phenotype. Furthermore, the thyroid differentiated functions were completely suppressed in PC myc cells transformed by PyMLV, whereas they were, at least partially, retained in PC Cl 3 cells transformed by PyMLV, and in particular, thyroglobulin synthesis and secretion were not affected at all. Since no differences in the expression of the middle-T-antigen gene were observed in the two PyMLV-transformed cell lines, the different properties shown by these two infected cell lines must be ascribed to the expression of the c-myc oncogene.


Asunto(s)
Antígenos Transformadores de Poliomavirus/fisiología , Transformación Celular Neoplásica/genética , Genes Virales , Oncogenes , Poliomavirus/fisiología , Proteínas Proto-Oncogénicas/fisiología , Animales , Línea Celular , Epitelio , Humanos , Poliomavirus/genética , Proteínas Proto-Oncogénicas c-myc , Ratas , Ratas Endogámicas F344 , Tiroglobulina/metabolismo , Glándula Tiroides
14.
Mol Cell Biol ; 7(9): 3365-70, 1987 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3670314

RESUMEN

A system of epithelial cells is described in which it is possible to study the number and the nature of genes capable of conferring the malignant phenotype. Two fully differentiated, hormone-responsive cell lines from rat thyroid glands are presented which are susceptible to one-step or two-step transformation upon infection with several murine acute retroviruses. After infection, both cell lines became independent from their thyrotropic hormone requirement for growth. However, complete transformation was achieved with one of the cell lines (FRTL-5 Cl 2), whereas the other cell line (PC Cl 3) failed to grow in agar and to give rise to tumors in vivo. The latter cell line was susceptible to complete transformation upon cooperation of the v-ras-Ha and the human c-myc oncogenes.


Asunto(s)
Transformación Celular Viral , Oncogenes , Retroviridae/patogenicidad , Glándula Tiroides/citología , Animales , Diferenciación Celular , Línea Celular Transformada , Células Epiteliales , Epitelio/fisiología , Yoduros/metabolismo , Neoplasias Experimentales/genética , ARN Mensajero/genética , ARN Neoplásico/genética , Ratas , Retroviridae/genética , Tiroglobulina/biosíntesis , Glándula Tiroides/fisiología
15.
Mol Cell Biol ; 14(1): 663-75, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8264635

RESUMEN

A chimeric expression vector which encoded for a molecule encompassing the extracellular domain of the epidermal growth factor (EGF) receptor (EGFR) and the intracellular domain of the ret kinase (EGFR/ret chimera) was generated. Upon ectopic expression in mammalian cells, the EGFR/ret chimera was correctly synthesized and transported to the cell surface, where it was shown capable of binding EGF and transducing an EGF-dependent signal intracellularly. Thus, the EGFR/ret chimera allows us to study the biological effects and biochemical activities of the ret kinase under controlled conditions of activation. Comparative analysis of the growth-promoting activity of the EGFR/ret chimera expressed in fibroblastic or hematopoietic cells revealed a biological phenotype clearly distinguishable from that of the EGFR, indicating that the two kinases couple with mitogenic pathways which are different to some extent. Analysis of biochemical pathways implicated in the transduction of mitogenic signals also evidenced significant differences between the ret kinase and other receptor tyrosine kinases. Thus, the sum of our results indicates the existence of a ret-specific pathway of mitogenic signaling.


Asunto(s)
Proteínas de Drosophila , Receptores ErbB/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Transducción de Señal/fisiología , Células 3T3/citología , Células 3T3/metabolismo , Animales , Secuencia de Bases , División Celular/genética , División Celular/fisiología , Línea Celular , ADN/genética , Receptores ErbB/genética , Proteínas Activadoras de GTPasa , Humanos , Inositol/metabolismo , Ratones , Datos de Secuencia Molecular , Fosfolípidos/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas/metabolismo , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-ret , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Transducción de Señal/genética , Transformación Genética
16.
J Natl Cancer Inst ; 60(5): 1127-31, 1978 May.
Artículo en Inglés | MEDLINE | ID: mdl-205662

RESUMEN

Four-week-old rainbow trout (Salmo gairdneri) were fed diets containing 0, 3, 50, 200, 400, and 800 ppm dimethylnitrosamine (DMN) for 52 weeks. At the end of 52 weeks, the fish were fed a control diet without DMN for an additional 26 weeks. Samples were taken at 26, 52, and 78 weeks to determine tumor incidence. A dose-related carcinogenic response was established from these results, and an equation was derived to relate the level of the carcinogen to the hepatocellular carcinoma incidence. From a published dose-response study that used outbred Porton rats, a second equation was derived for comparison. Rats and trout were approximately equal in their sensitivity to DMN carcinogenesis. The median lethal dose after ip injection of DMN was 1,770 mg/kg body weight in rainbow trout. Relative to the range of 15-50 mg/kg body weight reported for several mammalian species, trout were resistant to the acute toxicity of DMN.


Asunto(s)
Carcinógenos , Carcinoma Hepatocelular/inducido químicamente , Dimetilnitrosamina/toxicidad , Neoplasias Hepáticas/inducido químicamente , Nitrosaminas/toxicidad , Animales , Peso Corporal/efectos de los fármacos , Carcinoma Hepatocelular/patología , Dimetilnitrosamina/administración & dosificación , Relación Dosis-Respuesta a Droga , Femenino , Dosificación Letal Mediana , Neoplasias Hepáticas/patología , Masculino , Neoplasias Experimentales/inducido químicamente , Ratas , Especificidad de la Especie , Trucha
17.
Cancer Res ; 44(9): 4096-103, 1984 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6611203

RESUMEN

5'-Methylthioadenosine is a sulfur-containing nucleoside derived from the metabolism of polyamines which is known to exert an antiproliferative effect on several cell systems in vitro, including the Friend leukemia cell system. We have investigated the role of 5'-methylthioadenosine on the dimethyl sulfoxide-induced differentiation of this system. At a concentration of 400 microM, the drug strongly inhibited (80%) the induced differentiation of Friend cells, and this effect was already observable at a concentration as low as 10 microM (36% inhibition), as evidenced by the benzidine staining procedure and by the dot-blot hybridization of globin mRNA with a human beta-globin probe. Similar results have been obtained by using 5'-S-isobutylthioadenosine, which is a synthetic structural analogue of 5'-methylthioadenosine. The block of differentiation produced by these nucleosides was not mediated by adenine (a catabolite of both molecules) and was not reverted by spermine or spermidine, the two polyamines whose synthesis is inhibited by 5'-methylthioadenosine. We report a decrease of the aminopropyltransferases activities (the enzymes responsible for 5'-methylthioadenosine biosynthesis) in dimethyl sulfoxide-treated Friend cells, which could lead to a decrease of the intracellular content of 5'-methylthioadenosine during the erythroid maturation of Friend cells. The results obtained are consistent with the hypothesis that 5'-methylthioadenosine may act as an endogenous regulator of Friend cell differentiation.


Asunto(s)
Adenosina/análogos & derivados , Dimetilsulfóxido/farmacología , Leucemia Experimental/fisiopatología , Tionucleósidos/farmacología , Adenosina/farmacología , Animales , Diferenciación Celular/efectos de los fármacos , Línea Celular , Células Clonales , Desoxiadenosinas/análogos & derivados , Desoxiadenosinas/farmacología , Dimetilsulfóxido/antagonistas & inhibidores , Globinas/genética , Hemo/farmacología , Humanos , Cinética , Leucemia Mieloide Aguda/fisiopatología , Ratones , ARN Mensajero/aislamiento & purificación
18.
Cancer Res ; 48(13): 3816-21, 1988 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-3378218

RESUMEN

The expression of major histocompatibility complex (MHC) Class I antigens has been studied, by means of monoclonal antibodies directed against nonpolymorphic determinants of MHC Class I molecules, in two epithelial differentiated cell lines (FRTL-5 clone 2 and PC clone 3) and in one fibroblast cell line (FRT Fibro) of Fischer rat thyroid origin, before and after infection with various acute retroviruses carrying the v-ras-Ha, v-mos, v-src, polyoma middle T, and c-myc oncogenes. The results obtained indicate that a single virus does not produce identical changes in MHC Class I molecule expression in all tested lines, but a general increase occurs in lines derived from FRTL-5 clone 2 and a decrease occurs in lines derived from PC clone 3 and from FRT Fibro. Thus the modulation of expression seems to proceed always in the same direction in each cell line regardless of the infecting retrovirus and appears to involve posttranscriptional mechanisms, since no modification of expression of mRNA levels has been observed between normal and transformed cells. Only one line of PC clone 3 origin, transformed by the cooperation of two oncogenes (human c-myc and middle T), almost completely lost MHC Class I antigens on the cell surface and presented a significantly reduced synthesis of Class I mRNA.


Asunto(s)
Transformación Celular Viral , Genes MHC Clase I , Antígenos de Histocompatibilidad/fisiología , Animales , Antígenos de Neoplasias/fisiología , Línea Celular , Citometría de Flujo , Regulación de la Expresión Génica , Neoplasias Experimentales/inmunología , Oncogenes , ARN Mensajero/genética , Ratas
19.
Oncogene ; 8(2): 249-55, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8426735

RESUMEN

The PC Cl 3 cell line is a well characterized epithelial thyroid cell line of Fischer rat origin. This cell line has the peculiarity of retaining in vitro the typical markers of thyroid differentiation (i.e. thyroglobulin synthesis and secretion, iodide uptake and dependence on TSH for growth). The PC Cl 3 cells have been transfected with the E1A gene of Adenovirus 5. The E1A transfected cells, PC E1A, partially lost the dependency on TSH for growth and completely lost the ability to trap iodide and synthesize thyroglobulin; however they did not acquire the typical markers of the neoplastic phenotype. A highly malignant phenotype was achieved after infection of the PC E1A cells with retroviruses carrying the v-raf, v-abl and polyoma virus middle T oncogenes. In contrast, the PC E1A cells transfected with the E1B gene of Adenovirus were not tumorigenic at all, and those infected with retroviruses carrying oncogenes of the ras family displayed a very weak tumorigenic phenotype.


Asunto(s)
Proteínas E1A de Adenovirus/genética , Transformación Celular Neoplásica , Oncogenes , Glándula Tiroides/patología , Animales , Diferenciación Celular , Línea Celular , Epitelio/patología , Ratas , Ratas Endogámicas F344 , Transfección
20.
Oncogene ; 4(2): 181-8, 1989 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2538791

RESUMEN

The injection of a retrovirus carrying the v-ras-Ki oncogene into the thyroid gland of adult Fischer rats induces thyroid carcinomas when associated with a treatment of the animals with a goitrogenic agent. More than one hundred adult Fischer rats have been treated with the goitrogen agent propylthiouracil in order to induce thyroid hyperplasia. Twenty days after treatment, rat thyroid glands, surgically prepared, were injected with the Kirsten murine sarcoma virus (KiMSV). Within three months more than 90% of the animals developed thyroid tumors. Histologically the tumors had the appearance of well differentiated carcinomas. Thirty animals had lung metastases in addition to the thyroid carcinoma. The presence of KiMSV specific transcripts and the specific transforming protein (p21) in thyroid carcinomas and in the metastases was detected by Northern blot analysis and immunoprecipitation, respectively. Only three rats, among thirty that had not received the goitrogen treatment, but only the injection with KiMSV, developed thyroid carcinomas of very small size and with a very long latency period (almost one year). The results described represent the first instance of thyroid carcinoma induction by retroviruses. This system may be regarded as a useful model to investigate the process of thyroid carcinogenesis in vivo. These results suggest that this model may also be useful for investigating the interaction between hormones and cells harboring the activated oncogene in the development of thyroid carcinoma since activated ras oncogenes have been implicated in human thyroid carcinoma.


Asunto(s)
Carcinoma/etiología , Virus del Sarcoma Murino de Kirsten/genética , Virus del Sarcoma Murino/genética , Neoplasias de la Tiroides/etiología , Animales , Modelos Animales de Enfermedad , Genes ras , Metástasis de la Neoplasia , Proteína Oncogénica p21(ras) , Proteínas Oncogénicas Virales/análisis , Propiltiouracilo/farmacología , Ratas , Ratas Endogámicas F344 , Neoplasias de la Tiroides/análisis , Tirotropina/farmacología
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