RESUMO
Juvenile rainbow trout Oncorhynchus mykiss were exposed to two concentrations each of 17ß-oestradiol (E2; natural oestrogen hormone) or 17α-ethinyl oestradiol (EE2; a potent synthetic oestrogen hormone) to evaluate their potential effects on burst-swimming performance. In each of six successive burst-swimming assays, burst-swimming speed (Uburst ) was lower in fish exposed to 0.5 and 1 µg l(-1) E2 and EE2 for four days compared with control fish. A practice swim (2 days prior to exposure initiation) in control fish elevated initial Uburst values, but this training effect was not evident in the 1 µg l(-1) EE2-exposed fish. Several potential oestrogen-mediated mechanisms for Uburst reductions were investigated, including effects on metabolic products, osmoregulation and blood oxygen-carrying capacity. Prior to burst-swimming trials, fish exposed to E2 and EE2 for 4 days had significantly reduced erythrocyte numbers and lower plasma glucose concentrations. After six repeated burst-swimming trials, plasma glucose, lactate and creatinine concentrations were not significantly different among treatment groups; however, plasma Cl(-) concentrations were significantly reduced in E2- and EE2-treated fish. In summary, E2 and EE2 exposure altered oxygen-carrying capacity ([erythrocytes]) and an osmoregulatory-related variable ([Cl(-) ]), effects that may underlie reductions in burst-swimming speed, which will have implications for fish performance in the wild.
Assuntos
Estradiol/análise , Etinilestradiol/análise , Oncorhynchus mykiss/fisiologia , Natação , Poluentes Químicos da Água/análise , Animais , Glicemia/análise , Cloretos/análise , Exposição Ambiental , Eritrócitos/efeitos dos fármacos , Hematócrito , Hidrocortisona/sangue , Esforço Físico , Vitelogeninas/sangueRESUMO
Metastatic colorectal cancer (mCRC) patients carrying KRAS mutated tumors do not benefit from epidermal growth factor receptor (EGFR)-targeted cetuximab- or panitumumab-based therapies. Indeed, the mutational status of KRAS is currently a validated predictive biomarker employed to select mCRC patients for EGFR targeted drugs. When patients fail standard 5-fluorouracil-, oxaliplatin-, irinotecan- and bevacizumab-based therapies, EGFR-targeted salvage therapy can be prescribed only for those individuals with KRAS wild-type cancer. Thus, clinicians are now facing the urgent issue of better understanding the biology of KRAS mutant disease, in order to devise novel effective therapies in such defined genetic setting. In addition to KRAS, recent data point out that BRAF and PIK3CA exon 20 mutations hamper response to EGFR-targeted treatment in mCRC, potentially excluding from treatment also patients with these molecular alterations in their tumor. This review will focus on current knowledge regarding the molecular landscape of mCRC including and beyond KRAS, and will summarize novel rationally-developed combinatorial regimens that are being evaluated in early clinical trials.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/efeitos dos fármacos , Proteínas Proto-Oncogênicas/análise , Proteínas ras/análise , Animais , Anticorpos Monoclonais/uso terapêutico , Classe I de Fosfatidilinositol 3-Quinases , Neoplasias Colorretais/diagnóstico , Modelos Animais de Doenças , Humanos , Proteínas de Membrana/metabolismo , Mutação , Metástase Neoplásica/tratamento farmacológico , Metástase Neoplásica/genética , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas p21(ras) , Receptores de Superfície Celular/efeitos dos fármacos , Receptores de Superfície Celular/metabolismo , Terapia de Salvação , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Peripheral T-cell lymphoma unspecified (PTCLU) and mycosis fungoides (MF) often show resistance to conventional chemotherapy. Gemcitabine should be considered a suitable option. We report the long-term update of 39 pretreated T-cell lymphoma patients treated with gemcitabine. PATIENTS AND METHODS: From May 1997 to September 2007, 39 pretreated MF and PTCLU patients received gemcitabine. Inclusion criteria were as follows: histologic diagnosis of MF or PTCLU; relapsed/refractory disease; age > or =18 years; and World Health Organization performance status of two or less. Nineteen patients had MF and 20 PTCLU. All patients with MF had a T3-T4, N0, and M0 disease and patients with PTCLU had stage III-IV disease. Gemcitabine was given on days 1, 8, and 15 on a 28-day schedule (1200 mg/m(2)/day) for a total of three to six cycles. RESULTS: Overall response rate was 51% (20 of 39 patients); complete response (CR) and partial response (PR) rates were 23% (9 of 39 patients) and 28% (11 of 39 patients), respectively. Patients with MF had a CR rate of 16% and a PR rate of 32% compared with a CR rate of 30% and a PR rate of 25% of PTCLU patients. Among the CR patients, 7 of 9 are in continuous complete response with a variable disease-free interval (15-120 months). CONCLUSION: In our experience, gemcitabine proved to be effective in pretreated MF and PTCLU patients, even in the long term.
Assuntos
Desoxicitidina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos , Linfoma de Células T/tratamento farmacológico , Adulto , Idoso , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Quimioterapia Adjuvante , Desoxicitidina/efeitos adversos , Desoxicitidina/uso terapêutico , Feminino , Seguimentos , Humanos , Linfoma de Células T/complicações , Linfoma de Células T/radioterapia , Masculino , Pessoa de Meia-Idade , Micose Fungoide/complicações , Micose Fungoide/tratamento farmacológico , Recidiva , Neoplasias Cutâneas/complicações , Neoplasias Cutâneas/tratamento farmacológico , Fatores de Tempo , Resultado do Tratamento , GencitabinaRESUMO
BACKGROUND: Adult Langerhans cell histiocytosis (LCH) is a rare disease. The combination of vinblastine and prednisone, given in a 6-month course, is the standard of care but prospective randomized trials are lacking. PATIENTS AND METHODS: We report our monocentric experience in the treatment of seven adult patients with multisystem (MS) LCH (n = 3) or single-system multifocal (SS-m) LCH (n = 4) with the short-course intensive chemotherapy regimen methotrexate, doxorubicin, cyclophosphamide, vincristine, prednisone and bleomicin (MACOP-B). RESULTS: The overall response rate was 100% [five complete response (CR), two partial response (PR)]. After a median follow-up of 6.5 years, four patients are in first continuous CR and three patients relapsed after 5, 8 and 62 months, respectively. Four patients were evaluated with positron emission tomography (PET) scan: all three PET-negative patients at the end of treatment had a long-lasting response with only one patient relapsing after 5 years. PET scan detected additional bone lesions at diagnosis in two of four patients, changing the treatment program in one of them. CONCLUSIONS: MACOP-B regimen seems to be very active in the treatment of adult MS or SS-m LCH, with long-lasting responses in five of seven patients. PET scan merits further evaluation in the initial staging and in the evaluation of the response to chemotherapy.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Histiocitose de Células de Langerhans/tratamento farmacológico , Adolescente , Adulto , Bleomicina/uso terapêutico , Ciclofosfamida/uso terapêutico , Progressão da Doença , Doxorrubicina/uso terapêutico , Feminino , Fluordesoxiglucose F18 , Seguimentos , Histiocitose de Células de Langerhans/diagnóstico por imagem , Humanos , Leucovorina/uso terapêutico , Masculino , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Prednisona/uso terapêutico , Indução de Remissão , Estudos Retrospectivos , Vincristina/uso terapêutico , Adulto JovemRESUMO
OBJECTIVE: To describe the main characteristics of clinical research protocols submitted to Italian local ethics committees (LECs). DESIGN: Prospective survey on all research protocols evaluated during the period from 1 September 1998 to 31 July 1999. Data were prospectively collected for each individual study containing information on: general characteristics of the study; study design; population under study; LEC decision; and study monitoring. SETTING: Twenty Italian LECs from nine regions in Italy. MAIN OUTCOME MEASURES: Type of protocols, diseases and drugs under investigation, population under study, methodological characteristics (e.g. sponsorship, multicentricity, presence of a control group). RESULTS: Data on 449 protocols corresponding to 625 evaluations were received. The majority of protocols (83.1%, n=373) were investigational studies on drugs, sponsored 76.8% (n=345) and multicentre 86.4% (n=388). The majority of the drug protocols were on antineoplastic drugs (27.7%, n=104), cardiovascular agents (15.4%, n=58) and systemic anti-infective agents (13.8%, n=52). A few of the drugs investigated were new entities. A few studies focused on subpopulations, e.g. elderly and children (10 and 16, respectively). Early development phases (I and II) were less likely to be sponsored and multicentre. The most represented drug category in phase I-II trials was the antineoplastic agents. CONCLUSION: A small portion of research protocols submitted to LECs in Italy relate to innovative research. The new Italian legislation, which decentralizes approval of clinical trials from central to local levels, will lead to shorter approval times and should stimulate more original research. Surveys on LECs activity give important information on active research areas, methodological quality of current studies and outcome of the studies in terms of trial closure and publication of the results. The latter information may be obtained through a follow-up of the cohort of studies included in the present cross-sectional survey.
Assuntos
Ensaios Clínicos como Assunto/normas , Drogas em Investigação , Ética Médica , Tratamento Farmacológico/tendências , Pesquisas sobre Atenção à Saúde , Humanos , Itália , Estudos Prospectivos , Projetos de Pesquisa , Revelação da VerdadeRESUMO
The E6/E7-coding sequences of the human papillomavirus type 16 (HPV 16) were probed for kinetic accessibility in vitro by pools of catalytic antisense RNA. Only long-chain complementary RNA and very few antisense sequences with a 3' portion complementary to a 10 nt window within unspliced and spliced E6-coding target sequences showed fast annealing with k(ass) values of up to 10(4) M-1s-1 indicating that the majority of E6/E7 RNA sequences are unfavourable targets for antisense inhibitors and ribozymes. Fast-annealing antisense oligodeoxyribonucleotides directed against the window of 10 nt inhibited cell proliferation of HPV 16-transformed SiHa cells but not slow-annealing antisense species. Antisense RNA of several hundred nucleotides in length also showed significant anti-proliferative activity. Biological effects of antisense oligodeoxyribonucleotides were specific for the antisense sequence, could only be found in HPV-positive but not in HPV-negative cell lines, and were related to decreased levels of E7 protein and E6/E7-specific transcripts. This work suggests that HPV 16 E7/E6 sequences exhibit a low accessibility for antisense oligonucleotides. This can be overcome, however, by exploiting the relationship between fast annealing of antisense species and their increased efficacy in human cells.