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1.
Sci Total Environ ; 873: 162339, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36813191

RESUMEN

This study adds insight regarding the occurrence and spread of SARS-CoV-2 Variants of Concern (VOCs) and Variants of Interest (VOIs) in Italy in October and November 2022, by testing urban wastewater collected throughout the country. A total of 332 wastewater samples were collected from 20 Italian Regions/Autonomous Provinces (APs) within the framework of national SARS-CoV-2 environmental surveillance. Of these, 164 were collected in the first week of October and 168 in the first week of November. A ∼1600 bp fragment of the spike protein was sequenced by Sanger (for individual samples) and long-read nanopore sequencing (for pooled Region/AP samples). In October, mutations characteristic of Omicron BA.4/BA.5 were detected in the vast majority (91 %) of the samples amplified by Sanger sequencing. A fraction of these sequences (9 %) also displayed the R346T mutation. Despite the low prevalence documented in clinical cases at the time of sampling, amino acid substitutions characteristic of sublineages BQ.1 or BQ.1.1 were detected in 5 % of sequenced samples from four Regions/APs. A significantly higher variability of sequences and variants was documented in November 2022, when the rate of sequences harbouring mutations of lineages BQ.1 and BQ1.1 increased to 43 %, and the number of Regions/APs positive for the new Omicron subvariant more than tripled (n = 13) compared to October. Moreover, an increase in the number of sequences with the mutation package BA.4/BA.5 + R346T (18 %), as well as the detection of variants never observed before in wastewater in Italy, such as BA.2.75 and XBB.1 (the latter in a Region where no clinical cases associated with this variant had ever been documented) was recorded. The results suggest that, as predicted by the ECDC, BQ.1/BQ.1.1 is rapidly becoming dominant in late 2022. Environmental surveillance proves to be a powerful tool for tracking the spread of SARS-CoV-2 variants/subvariants in the population.


Asunto(s)
COVID-19 , Monitoreo Epidemiológico Basado en Aguas Residuales , Humanos , SARS-CoV-2/genética , Aguas Residuales , COVID-19/epidemiología , Italia
2.
Clin Nephrol ; 76(6): 425-34, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22105444

RESUMEN

BACKGROUND: Vascular calcifications (VC) are associated with cardiovascular (CV) morbidity and are independent predictors of CV mortality in end-stage renal disease (ESRD). This study aimed to investigate the presence of arterial intima calcification (AIC) and arterial media calcification (AMC) in nondiabetic patients on long-term hemodialysis, and to assess the association with CV risk factors. METHODS: 34 ESRD patients (17 males) on hemodialysis for at least 5 years were evaluated for VC using B-mode ultrasonography. RESULTS: AMC and AIC patterns were detected respectively in 62% and 59% of patients, and 21% had no VC. Patients with AIC were significantly older than those without AIC (p < 0.001). CRP levels (p < 0.001) were higher in patients with AMC. Using multivariate logistic analysis of regression, older age (> 50 years) and higher CRP levels (> 5 mg/l) were associated with AIC and AMC, respectively (p = 0.007 and p = 0.003). Logistic regression analysis showed that patients with CRP > 5 mg/l had a greater relative risk of having AMC (odds ratio 30, 95% confidence interval 27.041 - 32.959; p = 0.003). CONCLUSIONS: Ultrasonography can be used to detect AIC and AMC, and could be useful for the early detection of VC. In nondiabetic patients who had been on hemodialysis for at least 5 years, older age was associated with AIC, and elevated CRP levels with AMC.


Asunto(s)
Proteína C-Reactiva/análisis , Fallo Renal Crónico/complicaciones , Diálisis Renal , Túnica Media/metabolismo , Calcificación Vascular/diagnóstico por imagen , Adulto , Anciano , LDL-Colesterol/sangre , Femenino , Humanos , Resistencia a la Insulina , Fallo Renal Crónico/sangre , Modelos Logísticos , Masculino , Persona de Mediana Edad , Poliaminas/uso terapéutico , Sevelamer , Túnica Íntima/diagnóstico por imagen , Túnica Íntima/metabolismo , Túnica Media/diagnóstico por imagen , Ultrasonografía , Calcificación Vascular/sangre , Calcificación Vascular/etiología
3.
Int J Neurosci ; 113(3): 307-14, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12803135

RESUMEN

We report the case of a 24-year-old female with partial epilepsy, mental retardation, and dysmorphic facies. In EEG, a high spiking rate (HSR) was evident with abnormalities in the right frontal region. Morphological MRI showed a left temporo-mesial sclerosis and a cortical dysplasia localized in the right frontal cortex. Dynamic susceptibility contrast (DSC) MRI showed hyperperfusion in right frontal region and hypoperfusion in left fronto-temporal region. Left fronto-temporal hypoperfusion is consistent with temporo-mesial sclerosis. Right frontal hyperperfusion is related to the cortical dysplasia area with HSR. HSR may resemble both electroencephalographic and perfusional ictal pattern. DSC MRI is useful in the evaluation of regions involved in the genesis of ictal and interictal epileptiform activity. Furthermore, we hypothesize that our patient would be affected by a new possible genetic syndrome.


Asunto(s)
Epilepsias Parciales/fisiopatología , Discapacidad Intelectual/fisiopatología , Adulto , Atrofia/fisiopatología , Mapeo Encefálico , Electroencefalografía , Epilepsias Parciales/diagnóstico , Epilepsias Parciales/genética , Cara/anomalías , Femenino , Lóbulo Frontal/patología , Lóbulo Frontal/fisiopatología , Humanos , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/genética , Imagen por Resonancia Magnética , Lóbulo Temporal/patología , Lóbulo Temporal/fisiopatología
4.
Eur J Cancer ; 38(13): 1792-801, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12175697

RESUMEN

In this study, we evaluated the potential of the distamycin derivative MEN 10716 as a telomerase inhibitor. Exposure of human melanoma cell extracts to MEN 10716 induced a dose-dependent inhibition of telomerase activity, with an IC50 of 24+/-3 microM. When intact JR8 melanoma cells were chronically exposed to the drug (200 microM every other day for 50 days), a marked inhibition (>80%) of the enzyme's catalytic activity was consistently observed starting from day 1. At later points in time, MEN 10716 inhibited melanoma cell proliferation and induced apoptosis. Cells surviving MEN 10716 exposure were characterised by a higher melanin content and a greater expression of p16(INK4A) protein than control cells. The effects of MEN 10716 were subsequently evaluated in different tumour cell systems. In particular, even in the H460 non-small cell lung cancer cell line, chronic exposure of the cells to the drug (100 microM every other day for 50 days) induced a consistent inhibition (>85%) of telomerase activity, a reduction of cell proliferation potential, and apoptosis. Conversely, MEN 10716 treatment did not appreciably inhibit cell proliferation in the U2-OS telomerase-negative human osteogenic sarcoma cell line. Interestingly, no variation in the mean telomere length was observed in MEN 10716-treated JR8 melanoma cells, whereas an appreciable increase in the mean telomere length was found in H460 lung cancer cells after drug exposure. Overall, the results of the study indicate that MEN 10716 is a possible telomerase inhibitor and suggest that abrogation of telomerase activity can affect cell proliferation even through pathways that are not dependent on telomere erosion.


Asunto(s)
Antineoplásicos/uso terapéutico , Antivirales/farmacología , Distamicinas/farmacología , Distamicinas/uso terapéutico , Telomerasa/antagonistas & inhibidores , Apoptosis/efectos de los fármacos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/enzimología , División Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/enzimología , Melanoma/tratamiento farmacológico , Melanoma/enzimología , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/enzimología , Células Tumorales Cultivadas
5.
Eur J Cancer ; 37(5): 649-59, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11290441

RESUMEN

We evaluated the effects of the trinuclear platinum complex, BBR 3464, in a human ovarian carcinoma cell line (OAW42) and in its cisplatin (CDDP)-resistant counterpart (OAW42MER). A 14-fold increased sensitivity to a 1-h BBR 3464 exposure was found in OAW42MER cells compared with their parental cell line. Flow cytometric experiments showed that BBR 3464 was able to induce a persistent block of OAW42 and OAW42MER cells in the G2M phase, whereas CDDP caused an initial accumulation of cells in the S phase followed by an increase in the G2M cell fraction in both cell lines. Exposure to equitoxic (IC(50)) drug concentrations induced programmed cell death in both cell lines. However, the percentage of cells with an apoptotic nuclear morphology was slightly higher after CDDP than BBR 3464 treatment in OAW42 cells, whereas the opposite pattern was observed in OAW42MER cells. Degradation of the nuclear lamin B was detected in OAW42 cells after exposure to each drug. Conversely, in OAW42MER cells lamin B cleavage was only appreciable after BBR 3464 exposure. In OAW42 cells, CDDP and BBR 3464 did not appreciably affect the mitochondrial membrane potential (Deltapsi(mt)), whereas in the OAW42MER cell line a marked Deltapsi(mt) reduction was observed after exposure to BBR 3464, but not to CDDP. The results of the study would suggest that the sensitivity to BBR 3464 observed in the CDDP-resistant OAW42MER cell line might be attributable to the ability of the trinuclear platinum complex to modify DNA in a way which is different from that of CDDP and, as a consequence, to induce different cellular responses to DNA damage such as the triggering of specific apoptotic pathways.


Asunto(s)
Antineoplásicos/uso terapéutico , Compuestos Organoplatinos/uso terapéutico , Neoplasias Ováricas/tratamiento farmacológico , Apoptosis/efectos de los fármacos , Proteína Quinasa CDC2/metabolismo , Ciclo Celular/efectos de los fármacos , Ciclina B/metabolismo , Ciclina B1 , Resistencia a Antineoplásicos , Electroforesis en Gel de Agar , Femenino , Humanos , Immunoblotting , Neoplasias Ováricas/patología , Células Tumorales Cultivadas
6.
J Cell Biochem ; 81(1): 9-22, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11180394

RESUMEN

The effects of liposome-encapsulated annamycin (L-Ann) were investigated in two human breast cancer cell lines, MCF7 and MDA-MB-435. For comparative purposes, doxorubicin (Dx) was used throughout the study. A 4-hour treatment with L-Ann was significantly more active in MDA-MB-435 than in MCF7 cells (IC(50) values of 0.03 and 0.08 microg/ml, respectively), whereas Dx was equally active in the two cell lines (IC(50) 0.12 microg/ml). L-Ann induced an accumulation of cells in G2M phases which was dose-dependent in MDA-MB-435 but not in MCF7 cells. Dx also caused a dose-dependent increase of G2M cell fraction in MDA-MB-435 cells, whereas a G2M cell accumulation was observed only after treatment with the highest Dx concentration in MCF7 cells. G2M phase cell accumulations induced in MCF7 cells by L-Ann or Dx were accompanied by a decrease in cdc2 kinase activity and in cyclin B1 and cdc2 expression. Conversely, in MDA-MB-435 cells exposed to L-Ann or Dx, cdc2 kinase activity, cyclin B1 and cdc2 expression increased in parallel to the increase in the number of cells accumulated in the G2M phase. L-Ann and Dx induced apoptosis in MDA-MB-435 but not in MCF7 cells. In MDA-MB-435 cells exposed to L-Ann or Dx, no change was observed in the expression of bax, but there was a p53-independent increase in p21(waf1) expression. In MCF7 cells, treatment with L-Ann or Dx induced an increase in p53 expression with a consequent transactivation of p21(waf1) and bax. Our results indicate that L-Ann is more cytotoxic than Dx in breast cancer cells and is able to induce apoptosis through p53-independent mechanisms.


Asunto(s)
Apoptosis/efectos de los fármacos , Neoplasias de la Mama/patología , Ciclo Celular/efectos de los fármacos , Doxorrubicina/análogos & derivados , Doxorrubicina/farmacología , Doxorrubicina/administración & dosificación , Portadores de Fármacos , Humanos , Liposomas , Células Tumorales Cultivadas
7.
Ann Oncol ; 12(10): 1403-6, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11762811

RESUMEN

BACKGROUND: Due to the high mortality rates from gallbladder carcinoma in Chile, we conducted a phase II trial to test the efficacy and safety of gemcitabine in patients with locally advanced or metastatic gallbladder carcinoma. PATIENTS AND METHODS: From January 1998 to February 2000, 26 patients with metastatic or unresectable gallbladder carcinoma and no prior chemotherapy received gemcitabine 1,000 mg/m2 over 30 minutes weekly for three weeks followed by a week of rest. RESULTS: Patients received a median of 4.2 cycles (range 1-10). Out of the 25 patients whose response could be evaluated, 9 went into partial remission, an overall response rate of 36% (95% confidence interval (95% CI): 17.1% to 57.9%). In six (25.0%) patients, the cancer remained stable, and in 10 (40%) it progressed. Median survival time was 30 weeks (range 7-80+. Hematological toxicities were mild, with no cases of febrile neutropenia or hemorrhage. However, four and one patient(s) had grades 1-2 and 3-4 neutropenia, respectively, and two patients had grade 2 thrombocytopenia. Nine patients experienced grade 1-2 nausea/vomiting, but were able to continue treatment. There were no toxic deaths. CONCLUSIONS: In this phase II trial, gemcitabine is an active chemotherapy in metastatic or inoperable gallbladder carcinoma, with a manageable toxicity profile.


Asunto(s)
Antimetabolitos Antineoplásicos/farmacología , Carcinoma/tratamiento farmacológico , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Neoplasias de la Vesícula Biliar/tratamiento farmacológico , Adulto , Anciano , Antimetabolitos Antineoplásicos/administración & dosificación , Antimetabolitos Antineoplásicos/efectos adversos , Carcinoma/patología , Desoxicitidina/administración & dosificación , Desoxicitidina/efectos adversos , Supervivencia sin Enfermedad , Femenino , Fiebre/inducido químicamente , Neoplasias de la Vesícula Biliar/patología , Hemorragia/inducido químicamente , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Neutropenia/inducido químicamente , Resultado del Tratamiento , Gemcitabina
8.
Eur J Cancer ; 36(16): 2137-45, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11044653

RESUMEN

In tumour cells, replicative immortality is attained through stabilisation of telomeres by telomerase. Recent evidence suggests that telomerase plays an anti-apoptotic role. Since apoptosis is the primary mode of cell death induced by several drugs, telomerase could be involved in determining the chemosensitivity profile of tumour cells. We investigated whether inhibition of telomerase activity through a hammerhead ribozyme targeting the RNA template of telomerase influences the susceptibility of human melanoma cells to a variety of anticancer agents (platinum compounds, taxanes, topoisomerase I inhibitors). The ribozyme sequence was inserted into an expression vector and the JR8 human melanoma cell line was transfected with it. The cell clones obtained showed a reduced telomerase activity. Growth inhibition curves generated after exposure of ribozyme-transfectant clones to individual drugs were superimposable to those obtained from parental cells. Moreover, telomerase inhibition did not promote apoptosis as a cellular response to drug treatment. Overall, our results indicate that downregulation of telomerase activity does not increase the sensitivity of melanoma cells to anticancer drugs.


Asunto(s)
Antineoplásicos/uso terapéutico , Melanoma/tratamiento farmacológico , Melanoma/enzimología , Proteínas de Neoplasias/antagonistas & inhibidores , Telomerasa/antagonistas & inhibidores , Antineoplásicos/metabolismo , Apoptosis/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Melanoma/patología , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas/efectos de los fármacos
9.
Melanoma Res ; 9(5): 457-63, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10596912

RESUMEN

The ability of human recombinant interferon-alpha2a (IFNalpha2a) to induce the expression of cyclin-dependent kinase inhibitors p21waf1 and p27kip1 consequent to signal transducers and activators of transcription (STAT) protein activation was investigated in six human melanoma cell lines with different susceptibilities to the antiproliferative effect of the cytokine. All the cell lines expressed IFNalpha and IFNalpha/beta receptors. Exposure for 24 h to IFNalpha2a markedly enhanced the nuclear expression of STAT1 and STAT2 proteins in all the cell lines. However, no induction of p21waf1 or p27kip1 was consistently observed. Overall, results from the study suggest that the induction of such cyclin-dependent kinase inhibitors is not a major mechanism for the antiproliferative effect of IFNalpha2a, at least in human melanoma cell lines.


Asunto(s)
Proteínas de Ciclo Celular , Ciclinas/biosíntesis , Interferón-alfa/farmacología , Melanoma/metabolismo , Proteínas Asociadas a Microtúbulos/biosíntesis , Proteínas Supresoras de Tumor , Western Blotting , División Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Supervivencia Celular/efectos de los fármacos , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Inhibidor p27 de las Quinasas Dependientes de la Ciclina , Proteínas de Unión al ADN/biosíntesis , Relación Dosis-Respuesta a Droga , Citometría de Flujo , Humanos , Interferón alfa-2 , Melanoma/patología , Receptor de Interferón alfa y beta , Receptores de Interferón/biosíntesis , Proteínas Recombinantes , Factor de Transcripción STAT1 , Factor de Transcripción STAT2 , Factores de Tiempo , Transactivadores/biosíntesis , Células Tumorales Cultivadas
10.
Br J Cancer ; 81(2): 252-60, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10496350

RESUMEN

Mechanisms of resistance to Tomudex include increased thymidylate synthase activity, as well as reduced intracellular drug uptake and polyglutamation. However, little is known about other mechanisms of resistance, such as a possible protection against Tomudex-induced apoptosis mediated by bcl-2. We transfected the MDA-MB-435 human breast cancer cell line, which is characterized by a mutated p53 gene, with cDNA of the bcl-2 gene and generated two clones (MDA-bcl4 and MDA-bcl7) characterized by bcl-2 expression twofold and fourfold that observed in the control cell clone (MDAneo). A concomitant overexpression of p21wafl was also detected in the MDA-bcl7 clone. The MDA-bcl4 clone was three times more resistant to a 24-h Tomudex exposure than the MDAneo clone, whereas the MDA-bcl7 clone was as sensitive to Tomudex as the control cell clone. A lower sensitivity of the MDA-bcl4 clone than MDAneo and MDA-bcl7 clones to 5-fluorouracil and gemcitabine was also observed. No significant difference was noted in the susceptibility of clones to fludarabine and methothrexate. Basal levels of thymidylate synthase activity were superimposable in the three clones. Tomudex induced a marked accumulation of cells in the S phase in all the clones. However, an apoptotic hypodiploid DNA peak and the characteristic nuclear morphology of apoptosis were observed only in the MDA-bcl7 clone after exposure to Tomudex. No difference in the treatment-induced modulation of proteins involved in cell cycle progression (cyclin A, cdk2, pRB, E2F-1) and apoptosis (bcl-2, bax) was observed in the three clones. The only exception was that the expression of p21wafl in the MDA-bcl4 clone was inducible at a Tomudex concentration much higher than that required to induce the protein in the other clones. Overall, the results indicate that bcl-2 and p21wafl proteins concur in determining the cellular profile of sensitivity/resistance to Tomudex.


Asunto(s)
Antimetabolitos Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Ciclinas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Quinazolinas/farmacología , Tiofenos/farmacología , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/patología , Ciclo Celular/efectos de los fármacos , División Celular , Células Clonales , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Resistencia a Antineoplásicos , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Genes p53 , Humanos , Proteínas Proto-Oncogénicas c-bcl-2/genética , Timidilato Sintasa/metabolismo , Transfección , Células Tumorales Cultivadas
11.
Neuropsychologia ; 37(3): 333-43, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10199646

RESUMEN

Implicit, high level processing of extinguished objects has often been described in the visual modality. In the tactile domain, however, research on this topic is meagre and it is still uncertain whether processing of tactually presented stimuli can be affected by the same attentional disorders as visual stimuli. In this paper we describe a patient, ENM, with visual neglect and light touch extinction who, in a naming task of objects presented in the tactile modality, simultaneously to both hands, showed extinction for left hand objects. He was, nevertheless, able to make above chance Same/Different judgements on the two stimuli. We also tested two neurologically intact subjects who performed the test wearing a ski-glove on the left hand to impair the recognition of left hand objects. In these subjects, Same/Different judgements were at chance level when recognition rate was as low as that found in patient ENM. This happened when either the objects, although sharing the same name were different in shape (conditions Same-Different) or when the two objects were different with respect to the category name but were actually physically similar (conditions Different-Similar). However, when the objects were either identical or completely different, i.e., in a condition where judgement could be based simply on the physical analysis of the object shape (condition Same Identical and Different Dissimilar), their Same/Different judgements were above chance, despite the tactual deficit. Our conclusion was that patient ENM showed implicit recognition of left hand objects, at least in the Same Different and in the Different-Similar conditions, whereas, in the same conditions, normal subjects with an artificial sensory impairment did not. Our results also show that Same/Different judgements may be, in some conditions, less demanding than naming tasks, as suggested by Farah et al. Furthermore, patient ENM performed the test both with uncrossed and crossed hands. We found that extinction always affected the hand contralateral to the brain damage, although there was a tendency for a decrement of the ipsilesional hand performance in the crossed condition. We discuss these findings with reference to the most recent theories on the existence of a body centered spatial frame of reference.


Asunto(s)
Trastornos Cerebrovasculares/fisiopatología , Lateralidad Funcional , Procesos Mentales , Tacto , Percepción Visual , Anciano , Corteza Cerebral/patología , Corteza Cerebral/fisiología , Trastornos Cerebrovasculares/complicaciones , Trastornos Cerebrovasculares/psicología , Humanos , Masculino , Memoria
12.
Pediatr Med Chir ; 21(6): 285-7, 1999.
Artículo en Italiano | MEDLINE | ID: mdl-11293150

RESUMEN

The use of antiepileptic drugs in pregnancy may be responsible of minor or major developmental abnormalities at birth or in infancy. The severity of effects and heterogeneity of that abnormalities might be related to a special genetic background giving the fetus a predisposition for epilepsy and vulnerability to major or minor anomalies. The authors report the case of a pregnant woman self prescribing of a politherapy without medical control. She gave birth to a newborn with sever intrauterin retardation, various dysmorphic features and moderate psychomotor delayed.


Asunto(s)
Anomalías Inducidas por Medicamentos/etiología , Anticonvulsivantes/efectos adversos , Epilepsia/tratamiento farmacológico , Complicaciones del Embarazo/tratamiento farmacológico , Femenino , Humanos , Recién Nacido , Masculino , Embarazo
14.
Int J Oncol ; 14(1): 133-8, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9863019

RESUMEN

The ability of mitotane, a DDT derivative with adrenotoxic activity, and lonidamine, an energolytic derivative of indazole-carboxylic acid, to modulate the cytotoxic activity of doxorubicin, epidoxorubicin, cisplatin and VP16 was investigated in a human adrenocortical carcinoma cell line (SW13). A marked variability in cellular response to a 1-h treatment with the individual anticancer agents was observed. The concentrations able to inhibit SW13 cell proliferation by 50% (IC50) were 0.45 microg/ml and 0.4 microg/ml for doxorubicin and epidoxorubicin, respectively, thus indicating a relative sensitivity to anthracyclines. Conversely, the SW13 cell line displayed a marked resistance to cisplatin (IC50, 13.9 microg/ml) and VP16 (IC50, 15 microg/ml). When cells were exposed to anticancer drugs and mitotane simultaneously or in sequence, a positive modulation of anthracycline cytotoxic effects was observed. Although to a lesser extent, mitotane also increased cisplatin activity. Conversely, no potentiation was observed when mitotane was combined with VP16. Lonidamine slightly increased the cytotoxicity of epirubicin and cisplatin as individual agents. Moreover, a supra-additive effect of the three-drug (epidoxorubicin-cisplatin-lonidamine) combination was observed.


Asunto(s)
Neoplasias de la Corteza Suprarrenal/tratamiento farmacológico , Antineoplásicos/farmacología , Indazoles/farmacología , Mitotano/farmacología , Neoplasias de la Corteza Suprarrenal/patología , Sinergismo Farmacológico , Humanos , Células Tumorales Cultivadas
16.
J Biol Chem ; 273(50): 33455-64, 1998 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-9837924

RESUMEN

We have previously demonstrated that UCN-01, a potent protein kinase inhibitor currently in phase I clinical trials for cancer treatment, abrogates G2 arrest following DNA damage. Here we used murine FT210 cells, which contain temperature-sensitive Cdc2 mutations, to determine if UCN-01 abrogates G2 arrest through a Cdc2-dependent pathway. We report that UCN-01 cannot induce mitosis in DNA-damaged FT210 cells at the non-permissive temperature for Cdc2 function. Failure to abrogate G2 arrest was not due to UCN-01-inactivation at the elevated temperature because parental FM3A cells, which have wild-type Cdc2, were sensitive to UCN-01-induced G2 checkpoint abrogation. Having established that UCN-01 acted through Cdc2, we next assessed UCN-01's effect on the Cdc2-inhibitory kinase, Wee1Hu, and the Cdc2-activating phosphatase, Cdc25C. We found that Wee1Hu was indeed inactivated in UCN-01-treated cells, possibly just prior to Cdc2 activation and entry of DNA-damaged cells into mitosis. This inhibition appeared, however, to be a consequence of a further upstream action since in vitro studies revealed purified Wee1Hu was relatively resistant to UCN-01-inhibition. Consistent with such an upstream action, UCN-01 also promoted the hyperphosphorylation (activation) of Cdc25C in DNA-damaged cells. Our results suggest that UCN-01 abrogates G2 checkpoint function through inhibition of a kinase residing upstream of Cdc2, Wee1Hu, and Cdc25C, and that changes observed in these mitotic regulators are downstream consequences of UCN-01's actions.


Asunto(s)
Alcaloides/farmacología , Proteína Quinasa CDC2/metabolismo , Proteínas de Ciclo Celular/metabolismo , Inhibidores Enzimáticos/farmacología , Fase G2/efectos de los fármacos , Proteínas Nucleares , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Fosfatasas cdc25 , Alquenos/farmacología , Secuencia de Aminoácidos , Animales , Activación Enzimática , Ratones , Datos de Secuencia Molecular , Polienos , Pironas , Estaurosporina/farmacología , Células Tumorales Cultivadas
17.
Int J Cancer ; 78(3): 377-84, 1998 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-9766575

RESUMEN

The ability of lonidamine (LND), an energolytic derivative of indazole-carboxylic acid, to modulate the cytotoxicity of Taxol (TX) was investigated in the A2780 human ovarian cancer cell line. Different cytotoxicity results were obtained as a function of treatment schedule. Specifically, TX followed by LND produced synergistic effects. Conversely, antagonistic effects were recorded when drugs were given simultaneously or according to the opposite sequence. TX induced an oligonucleosomal DNA fragmentation typical of the apoptotic process. The extent and the kinetics of DNA cleavage in samples treated with the taxane alone were similar to those of samples treated with the TX-LND sequence. Activation of Yama protease and degradation of poly (ADP-ribose) polymerase were not observed after individual or combined treatment. LND did not appreciably modify the effect exerted by TX on proteins involved in cell cycle progression (i.e., inhibition of p34cdc2 expression) and apoptosis (i.e., upregulation of wt p53 and transactivation of p21waf1), and only caused a slight induction of the Bax protein. LND alone did not affect tubulin polymerization in A2780 cells and, when administered after a 24 hr TX exposure, did not appreciably alter the extent of tubulin polymerization induced by the taxane. Although additional studies are needed to define the molecular basis of the TX-LND interaction, our results suggest that LND can positively modulate the antitumor activity of TX in ovarian cancer cells and indicate that the energolytic is potentially useful in combination therapy including the taxane in ovarian cancer patients.


Asunto(s)
Antineoplásicos/toxicidad , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Indazoles/toxicidad , Paclitaxel/toxicidad , Caspasa 3 , Caspasas/metabolismo , Supervivencia Celular/efectos de los fármacos , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Ciclinas/biosíntesis , Ciclinas/genética , Sinergismo Farmacológico , Inhibidores Enzimáticos/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Índice Mitótico/efectos de los fármacos , Neoplasias Ováricas , Poli(ADP-Ribosa) Polimerasas/metabolismo , Protamina Quinasa/metabolismo , Tubulina (Proteína)/química , Tubulina (Proteína)/efectos de los fármacos , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/biosíntesis , Proteína p53 Supresora de Tumor/genética
18.
Br J Cancer ; 77(9): 1378-85, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9652752

RESUMEN

The effect of taxol (TX) and cisplatin (CDDP), singly or in association, was assessed on two human ovarian cancer cell lines, one sensitive (A2780) and one resistant (A2780 cp8) to CDDP. Cell lines showed a similar sensitivity to TX, whereas different cytotoxicity results were obtained in the two cell lines as a function of TX and CDDP sequence. Specifically, TX followed by CDDP induced simply additive effects in both cell lines, whereas the opposite sequence produced antagonistic effects in A2780 cells and synergistic effects in A2780 cp8 cells. TX, with or without CDDP, induced oligonucleosomal DNA fragmentation typical of the apoptotic process, but the biochemical mechanisms undergoing apoptosis were different in the two cell lines. In fact, in A2780 cells, TX (with or without CDDP) treatment markedly increased p53 as well as p21waf1 protein expression. In A2780 cp8 cells, drug treatment enhanced p53 levels, whereas the expression of p21waf1 was always undetectable at mRNA and protein levels. In the latter cell line, a premature activation of p34cdc2 kinase was observed in correspondence with the drug-induced increase in the S-phase cell fraction. Such an activation was not ascribable to an increase in the overall expression of p34cdc2 or cyclin B1 proteins, but to a dephosphorylation of p34cdc2 kinase. Overall, our results indicate that TX-induced apoptosis in human ovarian cancer cells may be sustained by different events at the cell cycle-control level.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Apoptosis/efectos de los fármacos , Proteínas de Ciclo Celular/efectos de los fármacos , Cisplatino/farmacología , Paclitaxel/farmacología , Proteínas de Ciclo Celular/metabolismo , Resistencia a Antineoplásicos , Femenino , Humanos , Neoplasias Ováricas/patología , Células Tumorales Cultivadas/efectos de los fármacos
19.
Melanoma Res ; 8(1): 31-8, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9508374

RESUMEN

We assessed the antiproliferative effects of human recombinant interferon-alpha2a (IFNalpha2a) and 13-cis-retinoic acid (13cis-RA) on two human melanoma cell lines (JR8 and M14). Both cell lines showed a very modest sensitivity to IFNalpha2a and 13cis-RA as single agents. In JR8 cells, the combination of the two compounds consistently produced simple additive effects. In contrast, different effects of the combination were recorded in the M14 cell line depending on the treatment schedule. Specifically, an additive interaction was observed when IFNalpha2a and 13cis-RA were given in sequence, independently of the order of drug administration, whereas a supra-additive antiproliferative effect was seen when cells were simultaneously exposed to the two drugs. Exposure to 1000 IU/ml IFNalpha2a markedly increased the nuclear expression of signal transducers and activators of transcription (STAT) proteins in both cell lines. By itself 10 microM 13cis-RA did not affect STAT protein expression or modify the extent of activation of such proteins by IFNalpha2a. Results from our study showed an enhancement of the antiproliferative activity of IFNalpha2a and 13cis-RA when given in combination and suggest that such an enhancement is not mediated by a concomitant effect of 13cis-RA on STAT protein activation.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Interferón-alfa/farmacología , Isotretinoína/farmacología , Melanoma/patología , Transactivadores/metabolismo , Recuento de Células/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Combinación de Medicamentos , Sinergismo Farmacológico , Humanos , Interferón alfa-2 , Melanoma/tratamiento farmacológico , Melanoma/metabolismo , Proteínas Recombinantes , Factor de Transcripción STAT1 , Factor de Transcripción STAT2 , Transducción de Señal/efectos de los fármacos , Células Tumorales Cultivadas
20.
Biomaterials ; 18(14): 955-61, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9212190

RESUMEN

This study aimed to assess the biocompatibility of two cordierite ceramics (DF and Cord 1014), with similar chemical composition and different porosity, as a potential support for cell growth in a continuous-flow, solid-bed reactor. The Chinese hamster ovary (CHO) cell line transfected with HBV-DHFR recombinant plasmid was seeded on cordierite or polystyrene dishes and evaluated for cell growth and production of recombinant hepatitis B surface antigen. Proliferation of the CHO cells, in terms of cell number, was generally similar in polystyrene and Cord 1014 and always lower in DF. Flow cytometric analysis showed no difference in cell cycle distribution for cells grown on different supports, and showed a two-fold increase in percentage of debris for cells grown on DF than for those grown on Cord 1014 and polystyrene culture dishes. Moreover, the morphology of cells grown on Cord 1014 did not change during the experiment, and cells were well spread and organized. Finally, total recombinant hepatitis B surface antigen production was higher on Cord 1014 than on polystyrene and DF samples. Such evidence suggests that Cord 1014 could be a promising support for growing cells in a continuous-flow, solid-bed reactor.


Asunto(s)
Materiales Biocompatibles/metabolismo , Reactores Biológicos , Células CHO/citología , Cerámica/metabolismo , Animales , Células CHO/inmunología , Células CHO/ultraestructura , Recuento de Células , Ciclo Celular , División Celular/fisiología , Células Cultivadas , Cerámica/química , Cricetinae , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Antígenos de Superficie de la Hepatitis B/biosíntesis , Microscopía Electrónica de Rastreo , Plásmidos/genética , Plásmidos/metabolismo , Poliestirenos , Porosidad , Proteínas Recombinantes/biosíntesis , Transfección
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