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1.
PLoS Biol ; 14(3): e1002401, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26942442

RESUMO

Demonstrations of both pro-apoptotic and pro-survival abilities of Fas (TNFRSF6/CD95/APO-1) have led to a shift from the exclusive "Fas apoptosis" to "Fas multisignals" paradigm and the acceptance that Fas-related therapies face a major challenge, as it remains unclear what determines the mode of Fas signaling. Through protein evolution analysis, which reveals unconventional substitutions of Fas tyrosine during divergent evolution, evolution-guided tyrosine-phosphorylated Fas proxy, and site-specific phosphorylation detection, we show that the Fas signaling outcome is determined by the tyrosine phosphorylation status of its death domain. The phosphorylation dominantly turns off the Fas-mediated apoptotic signal, while turning on the pro-survival signal. We show that while phosphorylations at Y232 and Y291 share some common functions, their contributions to Fas signaling differ at several levels. The findings that Fas tyrosine phosphorylation is regulated by Src family kinases (SFKs) and the phosphatase SHP-1 and that Y291 phosphorylation primes clathrin-dependent Fas endocytosis, which contributes to Fas pro-survival signaling, reveals for the first time the mechanistic link between SFK/SHP-1-dependent Fas tyrosine phosphorylation, internalization route, and signaling choice. We also demonstrate that levels of phosphorylated Y232 and Y291 differ among human cancer types and differentially respond to anticancer therapy, suggesting context-dependent involvement of Fas phosphorylation in cancer. This report provides a new insight into the control of TNF receptor multisignaling by receptor phosphorylation and its implication in cancer biology, which brings us a step closer to overcoming the challenge in handling Fas signaling in treatments of cancer as well as other pathologies such as autoimmune and degenerative diseases.


Assuntos
Evolução Molecular , Neoplasias/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Receptor fas/metabolismo , Quinases da Família src/metabolismo , Sequência de Aminoácidos , Apoptose , Endocitose , Humanos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Fosforilação , Estrutura Terciária de Proteína
2.
J Clin Oncol ; 30(36): 4558-65, 2012 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-23109696

RESUMO

PURPOSE: The ACCORD 12 trial investigated the value of two different preoperative chemoradiotherapy (CT-RT) regimens in T3-4 Nx M0 resectable rectal cancer. Clinical results are reported after follow-up of 3 years. PATIENTS AND METHODS: Between November 2005 and July 2008, a total of 598 patients were randomly assigned to preoperative CT-RT with CAP45 (45-Gy RT for 5 weeks with concurrent capecitabine) or CAPOX50 (50-Gy RT for 5 weeks with concurrent capecitabine and oxaliplatin). Total mesorectal excision was planned 6 weeks after CT-RT. The primary end point was sterilization of the operative specimen, which was achieved in 13.9% versus 19.2% of patients, respectively (P = .09). Clinical results were analyzed for all randomly assigned patients according to the intention-to-treat principle. RESULTS: At 3 years, there was no significant difference between CAP45 and CAPOX50 (cumulative incidence of local recurrence, 6.1% v 4.4%; overall survival, 87.6% v 88.3%; disease-free survival, 67.9% v 72.7%). Grade 3 to 4 toxicity was reported in four patients in the CAP45 group and in two patients in the CAPOX50 group. Bowel continence, erectile dysfunction, and social life disturbance were not different between groups. In multivariate analysis, the sterilization rate (Dworak score) of the operative specimen was the main significant prognostic factor (hazard ratio, 0.32; 95% CI, 0.21 to 0.50). CONCLUSION: At 3 years, no significant difference in clinical outcome was achieved with the intensified CAPOX regimen. When compared with other recent randomized trials, these results indicate that concurrent administration of oxaliplatin and RT is not recommended.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Retais/terapia , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Capecitabina , Quimiorradioterapia Adjuvante/efeitos adversos , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/análogos & derivados , Humanos , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/efeitos adversos , Estadiamento de Neoplasias , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Dosagem Radioterapêutica , Neoplasias Retais/patologia , Resultado do Tratamento
3.
J Clin Oncol ; 28(10): 1638-44, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20194850

RESUMO

PURPOSE: Neoadjuvant chemoradiotherapy is considered a standard approach for T3-4 M0 rectal cancer. In this situation, we compared neoadjuvant radiotherapy plus capecitabine with dose-intensified radiotherapy plus capecitabine and oxaliplatin. PATIENTS AND METHODS: We randomly assigned patients to receive 5 weeks of treatment with radiotherapy 45 Gy/25 fractions with concurrent capecitabine 800 mg/m(2) twice daily 5 days per week (Cap 45) or radiotherapy 50 Gy/25 fractions with capecitabine 800 mg/m(2) twice daily 5 days per week and oxaliplatin 50 mg/m(2) once weekly (Capox 50). The primary end point was complete sterilization of the operative specimen (ypCR). RESULTS: Five hundred ninety-eight patients were randomly assigned to receive Cap 45 (n = 299) or Capox 50 (n = 299). More preoperative grade 3 to 4 toxicity occurred in the Capox 50 group (25 v 1%; P < .001). Surgery was performed in 98% of patients in both groups. There were no differences between groups in the rate of conservative surgery (75%) or postoperative deaths at 60 days (0.3%). The ypCR rate was 13.9% with Cap 45 and 19.2% with Capox 50 (P = .09). When ypCR was combined with yp few residual cells, the rate was respectively 28.9% with Cap 45 and 39.4% with Capox 50 (P = .008). The rate of positive circumferential rectal margins (between 0 and 2 mm) was 19.3% with Cap 45 and 9.9% with Capox 50 (P = .02). CONCLUSION: The benefit of oxaliplatin was not demonstrated and this drug should not be used with concurrent irradiation. Cap 50 merits investigation for T3-4 rectal cancers.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Capecitabina , Quimioterapia Adjuvante , Terapia Combinada , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/análogos & derivados , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/efeitos adversos , Oxaliplatina , Dosagem Radioterapêutica , Radioterapia Adjuvante
4.
J Clin Oncol ; 24(28): 4620-5, 2006 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17008704

RESUMO

PURPOSE: In 1992, preoperative radiotherapy was considered in France as the standard treatment for T3-4 rectal cancers. The present randomized trial compares preoperative radiotherapy with chemoradiotherapy. PATIENTS AND METHODS: Patients were eligible if they presented a resectable T3-4, Nx, M0 rectal adenocarcinoma accessible to digital rectal examination. Preoperative radiotherapy with 45 Gy in 25 fractions during 5 weeks was delivered. Concurrent chemotherapy with fluorouracil 350 mg/m2/d during 5 days, together with leucovorin, was administered during the first and fifth week in the experimental arm. Surgery was planned 3 to 10 weeks after the end of radiotherapy. All patients should receive adjuvant chemotherapy with the same fluorouracil/leucovorin regimen. The primary end point of the trial was overall survival. RESULTS: A total of 733 patients were eligible. Grade 3 or 4 acute toxicity was more frequent with chemoradiotherapy (14.6% v 2.7%; P < .05). There was no difference in sphincter preservation. Complete sterilization of the operative specimen was more frequent with chemoradiotherapy (11.4% v 3.6%; P < .05). The 5-year incidence of local recurrence was lower with chemoradiotherapy (8.1% v 16.5%; P < .05). Overall 5-year survival in the two groups did not differ. CONCLUSION: Preoperative chemoradiotherapy despite a moderate increase in acute toxicity and no impact on overall survival significantly improves local control and is recommended for T3-4, N0-2, M0 adenocarcinoma of the middle and distal rectum.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/radioterapia , Antimetabólitos Antineoplásicos/farmacologia , Fluoruracila/farmacologia , Leucovorina/farmacologia , Radioterapia/métodos , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/radioterapia , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Retais/cirurgia , Recidiva , Complexo Vitamínico B/farmacologia
5.
Bull Cancer ; 93(2): 179-91, 2006 Feb.
Artigo em Francês | MEDLINE | ID: mdl-16517416

RESUMO

In response to the evolution of the information-seeking behaviour of patients and concerns from health professionals regarding cancer patient information, the French National Federation of Comprehensive Cancer Centres (FNCLCC) introduced, in 1998, an information and education program dedicated to patients and relatives, the SOR SAVOIR PATIENT program. The methodology of this program adheres to established quality criteria regarding the elaboration of patient information. Cancer patient information, developed in this program, is based on clinical practice guidelines produced by the FNCLCC and the twenty French regional cancer centres, the National League against Cancer, The National Cancer Institute, the French Hospital Federation, the National Oncology Federation of Regional and University Hospitals, the French Oncology Federation of General Hospitals, many learned societies, as well as an active participation of patients, former patients and caregivers. The handbook SOR SAVOIR PATIENT Understanding rectal cancer is an adapted version of the clinical practice guidelines (CPG) Standards, Options and Recommendations for rectal cancer. It is meant to provide a basis for the explanation of the disease and treatments and to facilitate discussions with the healthcare team. It is available from the FNCLCC (101, rue de Tolbiac, 75013 Paris, Tel. (0033) 1 44 23 04 68, www.fnclcc.fr). This document has been validated at the end of 2004 and published in 2005. SOR SAVOIR PATIENT guides are systematically updated when new research becomes available. Information leaflets, extracted from the handbook SOR SAVOIR PATIENT Understanding rectal cancer and published in this edition of the Bulletin du cancer, allow patients to better understand colonoscopy and colostomy, which represent an important patient information need. These articles are meant to inform patients and relatives about the disease and its treatments. It also offers health professionals a synthetic evidence-based patient information source which facilitates discussions with the patient.


Assuntos
Neoplasias Retais , Colonoscopia , Colostomia , Família , Humanos , Neoplasias Retais/diagnóstico , Neoplasias Retais/terapia
6.
Radiother Oncol ; 76(3): 241-50, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16165238

RESUMO

BACKGROUND AND PURPOSE: During the past decades staging and treatment of rectal cancer are used different in Europe and in North America. To promote a process to integrate the daily practice with the best evidence of the literature an International Conference was organized in Italy. Agreement between Experts, Centres, and specialists who participated in the Conference are reported. METHODS: Five aspects were analyzed and a questionnaire was tailored for this purpose. The questionnaire had 159 questions. During the Conference, at the beginning of each Session, the moderators showed the answers from the Experts and the Centres, and, at the end of the session, the audience voted in all controversial issues. Agreements were scored at three levels: minimum, if it was between 51 and 74% of votes for each group; moderate, between 75 and 94%; large, more than 94%. RESULTS: The main results are: staging: endoanal ultrasound was considered as mandatory in T staging, in the evaluation of sphincter infiltration, and in the restaging of T after chemoradiotherapy (chRT). Magnetic Resonance Imaging is mandatory in the evaluation of mesorectal fascia infiltration. Endoscopy had a moderate agreement for the definition of tumour location, and the barium enema as optional. Digital rectal examination is complementary for staging and PET-CT investigational for T, N and yT staging. Preoperative radiotherapy: for T4 stage chRT was always the preferred treatment, often with moderate agreement, for any tumour location and N status. For T3, chRT received the same agreement except for high location and N0-N1. For T2 stage, N2 and positive nodes outside the mesorectum, chRT received minimum agreement for low and middle tumours; for high tumours only positive nodes outside the mesorectum was agreed upon. Preoperative radiotherapy, negative specimen and sphincter preservation: chRT was agreed by many for all T stages and N presentations of lower third tumours, except for T1-2 N0-N1. Postoperative treatments: the selection for these treatments often received moderate agreement according to the infiltration of surrounding organs, positive nodal status and circumferential radial margins. Therapy of metastatic disease: an agreement was found for FOLFOX as first-line therapy and for FOLFIRI as second-line, although comparative studies show similar activity of FOLFOX and FOLFIRI regimens. CONCLUSIONS: This process represents an expertise opinion process that may contribute to increased scientific debate and to promote the development of 'guidelines', 'clinical recommendations' and ultimately a Consensus on the evolving approach to rectal cancer treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estadiamento de Neoplasias/métodos , Padrões de Prática Médica/estatística & dados numéricos , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Quimioterapia Adjuvante , Endoscopia Gastrointestinal , Pesquisas sobre Atenção à Saúde , Humanos , Cooperação Internacional , Imageamento por Ressonância Magnética , Seleção de Pacientes , Radioterapia Adjuvante
8.
J Clin Oncol ; 21(6): 1119-24, 2003 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-12637479

RESUMO

PURPOSE: The combination of radiation, fluorouracil, and oxaliplatin in locally advanced rectal cancer has been shown to be feasible in a phase I trial. The purpose of this phase II trial was to assess tolerance and efficacy of this regimen in a preoperative setting. PATIENTS AND METHODS: Between May 2000 and October 2001, 40 operable patients were entered onto the study. Radiotherapy was delivered with a three-field technique to a dose of 50 Gy over 5 weeks with a concomitant boost approach. Two cycles of chemotherapy were given synchronously on weeks 1 and 5, with oxaliplatin 130 mg/m(2) on day 1 followed by 5-day continuous infusion of fluorouracil 350 mg/m(2) and L-folinic acid 100 mg/m(2). Surgery was planned 5 weeks later. RESULTS: All patients completed treatment without modification except one who experienced grade 3/4 toxicity. Grade 3 toxicity was seen in seven patients. Surgery was performed in all patients after a mean interval time of 5 weeks. An objective clinical response was seen in 30 patients (75%). Sphincter-saving surgery was possible in 26 patients. No postoperative deaths occurred. In four patients (10%), a reoperation was necessary (anastomotic fistula, n = 2; pelvic abscess, n = 2). In six cases the operative specimen was sterilized (15%), and in 12 cases (30%), only few residual cells were detected. CONCLUSION: Such a combined preoperative chemoradiotherapy and oxaliplatin-containing regimen is well tolerated with no increase in surgical toxicity. The good response rate observed warrants its use in further clinical trials.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/radioterapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Neoadjuvante/métodos , Compostos Organoplatínicos/administração & dosagem , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/radioterapia , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimioterapia Adjuvante , Esquema de Medicação , Feminino , Fluoruracila/administração & dosagem , Humanos , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Oxaliplatina , Dosagem Radioterapêutica , Radioterapia Adjuvante , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Resultado do Tratamento
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