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1.
J Natl Cancer Inst ; 83(2): 111-6, 1991 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-1671103

RESUMO

In 20 women with breast carcinoma, 17 of whom had locally advanced cancer and 3 of whom had confirmed metastases, the expression of P-glycoprotein was evaluated before the start of a chemotherapy regimen that included multidrug resistance-related drugs. With the use of the C494 monoclonal antibody in an avidin-biotin-immunoperoxidase technique, P-glycoprotein was detected in 17 of 20 tumor samples. Results were expressed in a semiquantitative manner, taking into account the number of positive tumor cells (N index) and the specific staining intensity (I index). The 17 patients with nonmetastatic cancer were followed from the first cycle of chemotherapy to cancer recurrence; subsequent to six cycles of chemotherapy, all of these patients except one were rendered clinically disease-free through surgery and/or radiation. The end point was defined as either local/regional recurrence or metastasis. Strong P-glycoprotein-positive staining in a majority of tumor cells (the N+/I+ phenotype) was significantly correlated with no initial response to chemotherapy (P less than .02) and with a shorter progression-free survival (P less than .02). Thus, the pretreatment evaluation of P-glycoprotein expression may be of prognostic value in patients with locally advanced breast cancer.


Assuntos
Neoplasias da Mama/química , Carcinoma/química , Resistência a Medicamentos , Glicoproteínas de Membrana/análise , Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Adulto , Idoso , Anticorpos Monoclonais , Neoplasias da Mama/tratamento farmacológico , Carcinoma/tratamento farmacológico , Feminino , Humanos , Imuno-Histoquímica , Glicoproteínas de Membrana/imunologia , Pessoa de Meia-Idade , Fenótipo
2.
Cancer Res ; 44(2): 652-6, 1984 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6537898

RESUMO

By combining 5-fluorouracil and cis-diamminedichloro-platinum(II) at drug levels which are ineffective when used alone, we have cured L1210 leukemia in mice in a single treatment session. It was also discovered that the doses of the drugs used in this combination can be decreased, with no corresponding decrease in their effectiveness, if they are administered in conjunction with a very low dose of radiation (gamma-rays), which, when used alone, is ineffective. In the cells, the explanation for the synergic action of radiation, 5-fluorouracil, and cis-diamminedichloroplatinum(II) can be found in the action of each of the cytostatics at different phases of the cell cycle, each cytostatic favoring the action of the others. It is important to emphasize the order in which chemotherapy and radiotherapy are administered, as well as the time lapse between administration of the two treatments, maximum effectiveness having been obtained when radiotherapy was carried out 8 to 24 hr after chemotherapy.


Assuntos
Cisplatino/uso terapêutico , Fluoruracila/uso terapêutico , Leucemia L1210/terapia , Animais , Terapia Combinada , Raios gama , Masculino , Camundongos , Fatores de Tempo
3.
Cancer Res ; 45(7): 3150-4, 1985 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-4039976

RESUMO

The effectiveness of combined treatments of cis-diamminedichloroplatinum(II) (cis-DDP), 5-fluorouracil (5-FUra), and X-rays on growth inhibition of human pulmonary cancer nodules maintained in continuous organotypic culture was tested. To obtain the most effective growth inhibition, a cis-DDP treatment had to be preceded by an X-irradiation, whereas a 5-FUra treatment had to be postirradiated. This indicates the importance of the order in which the different combinations must be done. A mixture of 5-FUra and cis-DDP was even more effective than the X-ray and drug combination but only for a short period of time; reduction of nodule size and cell loss occurred during the 2 weeks following the treatment. After this period, as happened also with nodules treated with 5-FUra alone, vigorous regrowth occurred after treatment with cis-DDP plus 5-FUra, and all the nodules regained the size of the controls sooner or later. It is to be noted that, if X-rays were applied after a 5-FUra treatment, this regrowth is inhibited at least up to 45 days after the treatment.


Assuntos
Cisplatino/farmacologia , Fluoruracila/farmacologia , Neoplasias/patologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Terapia Combinada , Combinação de Medicamentos , Humanos , Neoplasias/terapia
4.
Int J Radiat Oncol Biol Phys ; 15(2): 341-6, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2457006

RESUMO

To minimize the drawbacks of treatment we had shown in a previous study that it was possible after chemotherapy to limit the radiation fields to the involved areas only. Pursuing our policy of deescalation, we started in January 1982 a study in 29 French pediatric and hematologic centers, with two aims: (1) To compare the efficacy of 4 cycles of two different chemotherapeutic regimens (4 ABVD vs 2 MOPP + ABVD) in early stages (CSIA and II A) while other stages would receive 6 cycles of the same regimen (3 MOPP + 3 ABVD); (2) To evaluate the efficacy of irradiation given at a low dose (20 Gy) in the patients who had a minimum 70% reduction of the size of their nodes (good responders). From January 1982 to March 1987, 174 patients were entered in this study, of whom 157 completed their treatment program at the time of analysis. On completion of chemotherapy, 94% were considered as good responders and were irradiated to 20 Gy. Only 6 patients received a mediastinal boost (up to 40 Gy). Of the 6% (10/157) poor responders a complete remission was obtained in 6 after 40 Gy. Among the good responders, 5 patients relapsed, with only 3 within an area irradiated to 20 Gy. So that 4 nodal relapses occurred among 364 involved lymph areas. The actuarial survival at 42 months (median 30 months) is 95% (IA + IIA = 100%, IB + IIB + III = 94% and IV = 80%) and the disease-free survival 88% (respectively 94, 93 and 54). Until now there is no statistically significant difference between the 2 randomized arms. This study shows that it is possible to achieve a durable remission in most children treated with a less toxic protocol eliminating or reducing Nitrogen Mustard and reducing the dose of irradiation. Less late complications and sequelae are expected with a longer follow-up.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doença de Hodgkin/terapia , Adolescente , Bleomicina/administração & dosagem , Criança , Pré-Escolar , Terapia Combinada , Dacarbazina/administração & dosagem , Doxorrubicina/administração & dosagem , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/radioterapia , Humanos , Mecloretamina/administração & dosagem , Prednisona/administração & dosagem , Procarbazina/administração & dosagem , Prognóstico , Dosagem Radioterapêutica , Vimblastina , Vincristina/administração & dosagem
5.
Radiother Oncol ; 11(2): 123-31, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3353517

RESUMO

Based on the synergistic action of 5-fluorouracil (5-FUra), cis-dichlorodiamminoplatinum(II) (cis-DDP) and gamma-rays, which was suggested in experiments on murine tumours, a sequential treatment combining irradiation and chemotherapy for human solid tumours known to be resistant to conventional treatments has been developed. A pilot study was carried out on 30 patients with recurring head and neck cancers previously treated by radiotherapy and surgery. The good tolerance and the initial results justified applying this protocol to previously untreated cases. The second study involved 40 patients with stage III and IV tumours. After 3 cycles of combined radio- and chemotherapy followed by a conventional radiotherapy, 78% were good responders (51% in complete remission). Oropharynx and oral cavity, without base of tongue, have a 51% actuarial survival at 3 years when they achieved an early complete remission.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias de Cabeça e Pescoço/terapia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/administração & dosagem , Terapia Combinada , Estudos de Avaliação como Assunto , Fluoruracila/administração & dosagem , Seguimentos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Radioterapia/efeitos adversos , Vômito/induzido quimicamente
6.
Radiat Res ; 97(1): 162-70, 1984 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6229806

RESUMO

The effect of the 2-nitroimidazole radiosensitizer misonidazole (MISO) and the hydrophilic analog SR-2508 on the repair of X-ray-induced potentially lethal damage (PLD) was studied in plateau-phase Chinese hamster ovary (HA-1) cells. It was found that although MISO does not radiosensitize aerobic cells, it inhibits the repair of PLD. However, under hypoxic conditions, MISO has no effect on PLD repair. The major portion of the inhibition of PLD repair in aerobic cells requires the presence of MISO only during irradiation; little or no additional inhibition occurs when MISO is present during the postirradiation repair period. Also, treatment of aerobic cells with 5 mM MISO for either 5 or 30 min prior to irradiation is equally inhibitory. This suggests that the presence of MISO in some way modifies the initial lesion under aerobic conditions since it does not increase cell killing as determined by immediate plating but inhibits subsequent repair. The inhibition is concentration dependent; 0.5 mM MISO inhibits PLD repair by one-half while 5-10 mM totally inhibits the repair measured 6 hr postirradiation. This phenomenon suggests that radiosensitization of tissue in vivo by MISO and other 2-nitroimidazoles may not be unequivocal proof of the presence of hypoxic cells.


Assuntos
Misonidazol/farmacologia , Nitroimidazóis/farmacologia , Ovário/efeitos da radiação , Lesões Experimentais por Radiação/prevenção & controle , Radiossensibilizantes/farmacologia , Aerobiose , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Cricetinae , Cricetulus , Relação Dose-Resposta a Droga , Etanidazol , Feminino , Ovário/efeitos dos fármacos , Fatores de Tempo
7.
Radiat Res ; 154(4): 406-11, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11023604

RESUMO

Human melanoma cells that are resistant to gamma rays were irradiated with 14 MeV neutrons given at low doses ranging from 5 cGy to 1.12 Gy at a very low dose rate of 0.8 mGy min(-1) or a moderate dose rate of 40 mGy min(-1). The biological effects of neutrons were studied by two different methods: a cell survival assay after a 14-day incubation and an analysis of chromosomal aberrations in metaphases collected 20 h after irradiation. Unusual features of the survival curve at very low dose rate were a marked increase in cell killing at 5 cGy followed by a plateau for survival from 10 to 32.5 cGy. The levels of induced chromosomal aberrations showed a similar increase for both dose rates at 7.5 cGy and the existence of a plateau at the very low dose rate from 15 to 30 cGy. The existence of a plateau suggests that a repair process after low-dose neutrons might be induced after a threshold dose of 5-7.5 cGy which compensates for induced damage from doses as high as 32.5 cGy. These findings may be of interest for understanding the relative biological effectiveness of neutrons and the effects of environmental low-dose irradiation.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos/efeitos da radiação , Melanoma/patologia , Nêutrons , Sobrevivência Celular/efeitos da radiação , Dano ao DNA , DNA de Neoplasias/efeitos da radiação , Relação Dose-Resposta à Radiação , Humanos , Tolerância a Radiação , Eficiência Biológica Relativa , Células Tumorais Cultivadas/patologia , Células Tumorais Cultivadas/efeitos da radiação
8.
Leuk Lymphoma ; 15(5-6): 419-32, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7873999

RESUMO

Most patients with Hodgkin's disease (HD) are cured with chemotherapy and/or radiotherapy. However, half of those with advanced stage disease (IIIB, IV) do not respond adequately to treatment or relapse. Salvage therapy used in such cases gives from 10% to 50% complete remission but only 10% long term survival. The results of bone marrow transplantation reported in acute leukemia and non-Hodgkin's lymphoma encouraged some authors to develop this new therapeutic strategy in Hodgkin's disease. In the early 1980's promising results were achieved when refractory and relapsed patients were selected to receive myeloablative therapy followed by bone marrow transplantation. Today, high dose chemotherapy with hematopoietic stem cell transplantation (HSCT) is used more and more often in poor prognosis Hodgkin's disease. After a review of the literature concerning the results of transplantation in Hodgkin's disease, we develop the numerous problems associated with this procedure which remain to be solved such as: the optimal indication, the timing of HSCT, the type of graft, the conditioning regimen, the place of radiotherapy and the optimal use of hematopoietic growth factors. We conclude with future prospects.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Doença de Hodgkin/terapia , Fatores Etários , Previsões , Fatores de Crescimento de Células Hematopoéticas/uso terapêutico , Doença de Hodgkin/radioterapia , Humanos , Pessoa de Meia-Idade , Fatores de Tempo
9.
Leuk Lymphoma ; 20(3-4): 259-66, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8624465

RESUMO

We report the experience of three French centres which evaluated high-dose therapy (HDT) as consolidation therapy for poor prognosis Hodgkin's disease (HD). From March 1986 to April 1990, 23 consecutive patients with poor prognosis stage IV HD underwent HDT followed by autologous bone marrow transplantation (ABMT) after achieving either complete remission (CR1) or good partial response (GPR1) (reduction mass> 75%). The median age was 31 years (range 18 to 55 years), 14 were male. All patients except one initially had at least 2 poor prognosis factors such as: systemic symptoms (n = 19), bulky tumor (n = 16), more than one extranodal site (n = 9), bone marrow involvement (n = 5), lymphocyte count < or = 1.10(9)/1 (n = 8) and biological stage B (n = 21). All patients had previously been treated with alternating MOPP/ABVD. Ten patients were in GPR1 and 13 in CR1 before transplant. The conditioning regimens were: CBV (n = 17), BEAM (n = 5), BEAC (n = 1) followed by bone marrow rescue. Radiotherapy was introduced just before the conditioning regimen for 6 patients or after ABMT for 5 patients. Nine of 10 patients in GPR1 achieved CR after ABMT but one died early of treatment-related toxicity. Five of 22 patients who were in CR posttransplant, relapsed (3, 4, 4, 18, 36 months). Seventeen patients remain alive in continuous CR with a median follow-up of 60 months (range: 30-100 months). The overall survival (OS) and disease-free survival (DFS) projected at 5 years are 92% and 77% respectively. Consolidation by HDT and ABMT proved to be well tolerated. An international trial is currently underway to attempt to demonstrate a clear benefit on survival for this subset of poor prognosis HD patients.


Assuntos
Transplante de Medula Óssea/métodos , Doença de Hodgkin/terapia , Adolescente , Adulto , Antineoplásicos/uso terapêutico , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Transplante Autólogo
10.
Anticancer Res ; 3(4): 257-62, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6192754

RESUMO

Residual colony forming ability (CFA) of cells from a human alveolar carcinoma (A549) was determined after 48 hours of contact with bleomycin (BLM) or cisdichlorodiammineplatinum (II) (DDP) using feeder cells arising from parallel cultures left in contact with sublethal BLM or DDP concentrations. The CFA of untreated cells was 60 to 80% (45% with X-irradiated feeder cells). Growing cultures were more resistant to DDP and more sensitive to BLM than plateau phase cultures. Subclones arising from a first treatment were resistant to a second BLM or X-ray treatment, but more sensitive to a second DDP treatment.


Assuntos
Adenocarcinoma Bronquioloalveolar/tratamento farmacológico , Bleomicina/farmacologia , Divisão Celular/efeitos dos fármacos , Cisplatino/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Adenocarcinoma Bronquioloalveolar/radioterapia , Divisão Celular/efeitos da radiação , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Células Clonais/efeitos dos fármacos , Células Clonais/efeitos da radiação , Humanos , Neoplasias Pulmonares/radioterapia
11.
Bull Cancer ; 86(4): 345-57, 1999 Apr.
Artigo em Francês | MEDLINE | ID: mdl-10341340

RESUMO

When cells are exposed to ionizing radiation, they initiate a complex response that includes the arrest of cell cycle progression in G1 and G2, apoptosis and DNA repair. DNA is an important subcellular target of ionizing radiation, but oxydative damage to plasma membrane lipids initiates signal transduction pathways that activate apoptosis and that may play a role in cell cycle regulation. How is DNA damage converted into intracellular signals for cell cycle arrest? The ataxia telangectasia mutant (ATM) protein and/or the DNA-dependent protein kinase (DNA-PK), that are both activated by DNA damage, may initiate cell cycle arrest by activating the p53 tumor suppressor protein. The p53 protein acts as a transcription factor and regulates expression of several components implicated in pathways that regulate cell cycle progression. The best known, p21WAF1/CIP1 protein, is an inhibitor of cyclin-dependent kinases (CDK), a family of protein kinases known as key regulators of cell cycle progression. p21WAF1/CIP1 was shown to be able to inhibit several CDK, but is most effective toward G1/S cyclins. Other CDK inhibitors, p27KIP1 and p15INK4b are activated by irradiation and contribute to the G1 arrest. Moreover, radiation-induced G2 arrest was shown to require inhibitory phosphorylation of the kinase cdc2 via an ATM-dependent pathway. Mutations in cell cycle regulatory genes are common in human cancer and cell cycle regulatory deficiency can lead to increase resistance to ionizing radiation in cancer cells. The major function of p53-dependent G1 arrest may be elimination of cells containing DNA damage whereas G2 arrest following radiation has been shown to be important in protecting cells from death. Cell cycle checkpoints offer a new set of potential targets for chemotherapeutic compounds, especially the G2 checkpoint. Thus, abrogation of the G2 checkpoint with methylxanthines such as caffeine or protein kinase inhibitors such as staurosporine and UCN-01 (7-hydroxystaurosporine) was found to sensitize cells to ionizing radiation. These data did not lead to clinical applications, but confirm targeting of the G2 checkpoint may be an important strategy for cancer therapy.


Assuntos
Ciclo Celular/efeitos da radiação , Quinases Ciclina-Dependentes/fisiologia , Dano ao DNA/fisiologia , Reparo do DNA/fisiologia , Proteína Supressora de Tumor p53/fisiologia , Apoptose/fisiologia , Ciclo Celular/genética , Ciclo Celular/fisiologia , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas , DNA/efeitos da radiação , Fase G1/fisiologia , Fase G1/efeitos da radiação , Fase G2/fisiologia , Fase G2/efeitos da radiação , Genes p53/fisiologia , Humanos , Neoplasias/tratamento farmacológico , Proteínas Quinases/fisiologia , Transdução de Sinais
12.
Bull Cancer ; 81(7): 625-31, 1994 Jul.
Artigo em Francês | MEDLINE | ID: mdl-7742606

RESUMO

From 1977 to 1989, we measured serum beta-2-microglobulin (beta 2-MG) levels from 64 unselected and untreated patients, between 18 to 50-year-old, affected by Hodgkin's disease. Serum beta 2-MG level was measured by radioimmunoassay (Phadebas beta 2 microtest). Then, all patients received a chemotherapy such as MOPP or alternating MOPP/ABVD followed or not by radiotherapy. Elevated serum beta 2-MG level (> 2.4 mg/l) is associated with advanced stage disease (stage III-IV), presence of systemic symptoms and bulky tumor. Nevertheless, a multivariate analysis shows that the serum beta 2-MG level is the most significant prognostic indicator for disease free survival. The prognostic value of serum beta 2-MG is demonstrated for myeloma and non Hodgkin's lymphoma. A few authors have evaluated the prognostic impact of serum beta 2-MG in Hodgkin's disease. This study requires confirmation by multicentric and prospective trial.


Assuntos
Biomarcadores Tumorais/sangue , Doença de Hodgkin/sangue , Microglobulina beta-2/análise , Adolescente , Adulto , Fatores Etários , Terapia Combinada , Feminino , Doença de Hodgkin/patologia , Doença de Hodgkin/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Prognóstico , Análise de Sobrevida
13.
Bull Cancer ; 73(3): 288-93, 1986.
Artigo em Francês | MEDLINE | ID: mdl-3463371

RESUMO

The authors evaluated a new protocol of neoadjuvant chemotherapy for osteosarcoma, easier to manage and different from T10. The good results obtained with the postoperative ADR-CDDP association led us to undertake a pilot study between 1982 and 1984, using ADR-CDDP as preoperative chemotherapy. The records of sixteen patients were available for follow-up. The average age of the patients was 19.9 years. Patients received two or three preoperative courses, and a total of six identical courses. Tolerance was good. Pain usually disappeared but this was often misleading because associated with radiological and/or clinical tumor progression, low histological necrosis or poor outcome. The continuous disease-free survival actuarial rate was less than 57 and 40% at 18 months and two years respectively. The actuarial survival rate was 87% at one year and 65% at two years respectively. Disappointing results of this preoperative protocol, compared to results with the SO4 78 or T10 protocols for example, led to publish these data early in order to underline their potential dangers. As a result, we stopped our study. The charter of pilot studies justifies this publication. As well, these data point out the necessity of very close follow-up of neoadjuvant chemotherapy by sophisticated medical imaging. Neoadjuvant chemotherapy, if ineffective, must be stopped early, and should lead to surgery, followed by adequate postoperative chemotherapy.


Assuntos
Neoplasias Ósseas/tratamento farmacológico , Cisplatino/uso terapêutico , Doxorrubicina/uso terapêutico , Osteossarcoma/tratamento farmacológico , Adolescente , Adulto , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/fisiopatologia , Criança , Cisplatino/efeitos adversos , Doxorrubicina/efeitos adversos , Humanos , Osteossarcoma/diagnóstico por imagem , Osteossarcoma/fisiopatologia , Prognóstico , Radiografia
14.
Bull Cancer ; 73(5): 620-6, 1986.
Artigo em Francês | MEDLINE | ID: mdl-3779144

RESUMO

One hundred and fifty patients, treated for Hodgkin's disease (stages I-IIIA) in a cooperative trial and remaining in complete remission after 2 to 7 years, answered a questionnaire dealing with psychosocial status and quality of life. Many informations were gathered and studied by multiparametric methods. Quality of life of patients appears determined by three kinds of parameters: patients' characteristics (age, sex, family and work status); stage of the disease determining the intensity and duration of treatment; practical conditions of treatment. These last parameters may be improved by therapeutic team and all care-takers to decrease bad consequences of disease and treatment and also to increase quality of life after cure.


Assuntos
Doença de Hodgkin/psicologia , Adolescente , Adulto , Idoso , Atitude Frente a Saúde , Feminino , Doença de Hodgkin/complicações , Doença de Hodgkin/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Psicologia Social , Qualidade de Vida , Fatores Socioeconômicos , Inquéritos e Questionários , Fatores de Tempo
15.
Bull Cancer ; 73(3): 305-10, 1986.
Artigo em Francês | MEDLINE | ID: mdl-3756367

RESUMO

One hundred and fifty patients treated for Hodgkin's disease (stage I to IIIA) in a cooperative trial, answered a questionnaire dealing partly with their information, after 2 to 7 years of complete remission. This information appears insufficient for the majority of patients (52%), at least as far as treatment and its complications are concerned. There are many significant relations with other parameters which suggest that a good level of information may improve quality of life of patients. These observations tend to increase information of patients with Hodgkin's disease, provided it is adapted to each patient.


Assuntos
Doença de Hodgkin/terapia , Qualidade de Vida , Seguimentos , Doença de Hodgkin/psicologia , Humanos , Educação de Pacientes como Assunto , Projetos Piloto , Inquéritos e Questionários
16.
Bull Cancer ; 83(2): 107-13, 1996 Feb.
Artigo em Francês | MEDLINE | ID: mdl-8652904

RESUMO

Recent studies have shown that experimental tumors could be treated more efficiently with ionizing radiation if genetic material was transfered into tumor cells. Several approaches have been reported, and among them, the first one consisted of increasing the apoptotic response to radiation by modulating genes involved in the regulation of the apoptotic pathway. Indeed the modulation of p53 and bcl-2 gene expression has recently been used successfully in several experimental models to increase the apoptotic death after radiation. A second approach consisted of taking advantage of the conditional expression of some genes after exposure to ionizing radiation. Indeed, some genes exhibit a radio-inducible promoter which can be combined to a gene, able to enhance or decrease the biological effect of radiation. The irradiation of such a transgene under the control of a radio-inducible promoter can lead to a second biological effect, concomitant to the irradiation, as reported for the TNF alpha under the control of the EGR (early growth response) promoter. A third approach consisted of enhancing the effect of radiation induced tumor cell death by the expression of a suicide gene in these cells, as suggested recently for the HSV-tk (herpes virus thymidine kinase gene). These preliminary results obtained in experimental models appear to be very promising and might improve the efficacy and specificity of radiation therapy in a not too distant future.


Assuntos
Apoptose/efeitos da radiação , Técnicas de Transferência de Genes , Neoplasias Experimentais/radioterapia , Neoplasias/radioterapia , Animais , Apoptose/genética , Morte Celular/efeitos da radiação , Regulação da Expressão Gênica/efeitos da radiação , Genes Supressores de Tumor/efeitos da radiação , Vetores Genéticos , Humanos , Técnicas In Vitro , Camundongos , Neoplasias/genética , Neoplasias Experimentais/genética , Proto-Oncogenes/efeitos da radiação , Transcrição Gênica , Células Tumorais Cultivadas
17.
Radiat Prot Dosimetry ; 99(1-4): 47-8, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12194356

RESUMO

The structure of the survival curve of melanoma cells irradiated by 14 MeV neutrons displays unusual features at very low dose rate where a marked increase in cell killings at 0.05 Gy is followed by a plateau for survival from 0.1 to 0.32 Gy. In parallel a simulation code was constructed for the interaction of 14 MeV neutrons with cellular cultures. The code describes the interaction of the neutrons with the atomic nuclei of the cellular medium and of the external medium (flask culture and culture medium), and is used to compute the deposited energy into the cell volume. It was found that the large energy transfer events associated with heavy charged recoils can occur and that a large part of the energy deposition events are due to recoil protons emitted from the external medium. It is suggested that such events could partially explain the experimental results.


Assuntos
Sobrevivência Celular/efeitos da radiação , Nêutrons , Simulação por Computador , Relação Dose-Resposta à Radiação , Humanos , Melanoma , Radiometria/métodos , Espalhamento de Radiação , Células Tumorais Cultivadas
18.
Presse Med ; 17(41): 2183-5, 1988 Nov 19.
Artigo em Francês | MEDLINE | ID: mdl-2849770

RESUMO

Seven children, aged from 9 to 16 years, with intracranial germ cell tumour received post-operative chemotherapy prior to radiotherapy. Treatment consisted of several courses of vinblastine, bleomycin and cisplatin alternating or not with courses of cyclophosphamide and actinomycin D. In the 6 children whose tumours secreted alphafoetoprotein or chorionic gonadotrophin, chemotherapy brought these markers down to normal. Tumoral regression at radiology exceeded 75 per cent in 6 patients. These results demonstrate the effectiveness of chemotherapy against intracranial germ cell tumours such as pure germinomas or secreting tumours. They encourage the systematic use of pre-irradiation chemotherapy in order to reduce the radiation doses delivered and to improve the prognosis.


Assuntos
Neoplasias Encefálicas/terapia , Neoplasias Embrionárias de Células Germinativas/terapia , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirurgia , Criança , Terapia Combinada , Disgerminoma/radioterapia , Disgerminoma/cirurgia , Feminino , Humanos , Masculino , Recidiva Local de Neoplasia , Neoplasias da Coluna Vertebral/secundário , Fatores de Tempo
19.
Ann Urol (Paris) ; 22(4): 229-34, 1988.
Artigo em Francês | MEDLINE | ID: mdl-3056230

RESUMO

Intravesical chemotherapy is widely used in the management of superficial urinary bladder tumors. A complete response rate of 30 to 50% is observed in unresected tumors. Prophylactic instillations of the drugs after transurethral resection of the tumors seem able to delay recurrences. BCG can also be as effective, particularly in carcinoma in situ. Confirmation of efficacy of retinoids needs further studies. Invasive or metastatic bladder carcinoma can be responsive to systemic chemotherapy in about 40% of the cases for a period of 6 to 12 months. The value of adjuvant chemotherapy remains to be proved. Enhancement of radiation therapeutic effects by CisPlatinum in an interesting field of clinical research.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias da Bexiga Urinária/tratamento farmacológico , Administração Intravesical , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Humanos , Imunoterapia , Metástase Neoplásica/prevenção & controle , Recidiva Local de Neoplasia/prevenção & controle , Neoplasias da Bexiga Urinária/radioterapia , Neoplasias da Bexiga Urinária/terapia
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