Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 61
Filtrar
1.
Ann Oncol ; 28(10): 2429-2435, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28961832

RESUMO

BACKGROUND: This randomized study was designed to investigate the superiority of gemcitabine (gem) plus nimotuzumab (nimo), an anti-epidermal growth factor receptor monoclonal antibody, compared with gem plus placebo as first-line therapy in patients with advanced pancreatic cancer. PATIENTS AND METHODS: Patients with previously untreated, unresectable, locally advanced or metastatic pancreatic cancer were randomly assigned to receive gem: 1000 mg/m2, 30-min i.v. once weekly (d1, 8, 15; q29) and nimo: fixed dose of 400 mg once weekly as a 30-min infusion, or gem plus placebo, until progression or unacceptable toxicity. The primary end point was overall survival (OS), secondary end points included time to progression, overall response rate, safety and quality of life. RESULTS: A total of 192 patients were randomized, with 186 of them being assessable for efficacy and safety (average age 63.6 years). One-year OS/progression-free survival (PFS) was 34%/22% for gem plus nimo compared with 19%/10% for gem plus placebo (HR = 0.69; P = 0.03/HR = 0.68; P = 0.02). Median OS/PFS was 8.6/5.1 months for gem plus nimo versus 6.0/3.4 mo in the gem plus placebo group (HR = 0.69; P = 0.0341/HR = 0.68; P = 0.0163), with very few grade 3/4 toxicities. KRAS wildtype patients experienced a significantly better OS than those with KRAS mutations (11.6 versus 5.6 months, P = 0.03). CONCLUSION: This randomized study showed that nimo in combination with gem is safe and well tolerated. The 1-year OS and PFS rates for the entire population were significantly improved. Especially, those patients with KRAS wildtype seem to benefit. The study was registered as protocol ID OSAG101-PCS07, NCT00561990 and EudraCT 2007-000338-38.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/uso terapêutico , Intervalo Livre de Doença , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/enzimologia , Placebos , Taxa de Sobrevida , Gencitabina
2.
Colorectal Dis ; 18(4): 364-71, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26400556

RESUMO

AIM: Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is an experimental drug delivery method that applies chemotherapy into the abdominal cavity as an aerosol under pressure. We present the first results obtained with PIPAC in colorectal peritoneal metastasis (CPM). METHOD: This is a retrospective analysis. PIPAC was applied in 17 consecutive patients with pretreated CPM. All patients had previously undergone surgery, and 16 had undergone previous lines of systemic chemotherapy (median, two lines). The mean peritoneal metastasis index (peritoneal cancer index) was 16 ± 10. Forty-eight applications of PIPAC with oxaliplatin (92 mg/m2 ) were given every 6 weeks at 37 °C and 12 mmHg for 30 min. The outcome criteria were microscopic pathological response, survival and adverse events according to Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. RESULTS: Forty-eight PIPAC administrations were performed with no intra-operative complications. The mean number of PIPAC administrations per patient was 2.8 (minimum one, maximum six). Postoperative adverse events (CTCAE level 3) were observed in four patients (23%), no CTCAE level-4 adverse events were reported. The hospital mortality was zero. Objective tumour responses were observed in 12/17 patients (71%), and the overall responses were as follows: complete pathological response (seven patients), major response (four patients), partial response (one patient), no response (two patients) and not eligible (three patients). The mean survival after first PIPAC was 15.7 months. CONCLUSION: Repeated PIPAC with oxaliplatin can induce the regression of pretreated CPM. The toxicity appears to be low. These preliminary results are encouraging and justify prospective clinical studies.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Compostos Organoplatínicos/administração & dosagem , Neoplasias Peritoneais/tratamento farmacológico , Aerossóis , Idoso , Neoplasias Colorretais/patologia , Ar Comprimido , Feminino , Humanos , Infusões Parenterais/métodos , Masculino , Pessoa de Meia-Idade , Oxaliplatina , Neoplasias Peritoneais/secundário , Estudos Retrospectivos , Resultado do Tratamento
3.
Ann Oncol ; 24(6): 1560-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23493136

RESUMO

BACKGROUND: Metastatic colorectal cancer (mCRC) is commonly treated with 5-fluorouracil, folinic acid, and oxaliplatin or irinotecan. The multitargeted kinase inhibitor, regorafenib, was combined with chemotherapy as first- or second-line treatment of mCRC to assess safety and pharmacokinetics (primary objectives) and tumor response (secondary objective). PATIENTS AND METHODS: Forty-five patients were treated every 2 weeks with 5-fluorouracil 400 mg/m(2) bolus then 2400 mg/m(2) over 46 h, folinic acid 400 mg/m(2), and either oxaliplatin 85 mg/m(2) or irinotecan 180 mg/m(2). On days 4-10, patients received regorafenib 160 mg orally once daily. RESULTS: The median duration of treatment was 108 (range 2-345 days). Treatment was stopped for adverse events or death (17 patients), disease progression (11 patients), and consent withdrawal or investigator decision (11 patients). Six patients remained on regorafenib at data cutoff (two without chemotherapy). Drug-related adverse events occurred in 44 patients [grade ≥ 3 in 32 patients: mostly neutropenia (17 patients) and leukopenia, hand-foot skin reaction, and hypophosphatemia (four patients each)]. Thirty-three patients achieved disease control (partial response or stable disease) for a median of 126 (range 42-281 days). CONCLUSION: Regorafenib had acceptable tolerability in combination with chemotherapy, with increased exposure of irinotecan and SN-38 but no significant effect on 5-fluorouracil or oxaliplatin pharmacokinetics.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Camptotecina/farmacocinética , Neoplasias Colorretais/metabolismo , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/farmacocinética , Humanos , Leucovorina/administração & dosagem , Leucovorina/farmacocinética , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/farmacocinética , Compostos de Fenilureia/administração & dosagem , Compostos de Fenilureia/farmacocinética , Piridinas/administração & dosagem , Piridinas/farmacocinética , Resultado do Tratamento , Adulto Jovem
4.
Br J Cancer ; 106(11): 1722-7, 2012 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-22568966

RESUMO

BACKGROUND: In a phase I dose-escalation study, regorafenib demonstrated tolerability and antitumour activity in solid tumour patients. The study was expanded to focus on patients with metastatic colorectal cancer (CRC). METHODS: Patients received oral regorafenib 60-220 mg daily (160 mg daily in the extension cohort) in cycles of 21 days on, 7 days off treatment. Assessments included toxicity, response, pharmacokinetics and pharmacodynamics. RESULTS: Thirty-eight patients with heavily pretreated CRC (median 4 prior lines of therapy, range 0-7) were enrolled in the dose-escalation and extension phases; 26 patients received regorafenib 160 mg daily. Median treatment duration was 53 days (range 7-280 days). The most common treatment-related toxicities included hand-foot skin reaction, fatigue, voice change and rash. Twenty-seven patients were evaluable for response: 1 achieved partial response and 19 had stable disease. Median progression-free survival was 107 days (95% CI, 66-161). At steady state, regorafenib and its active metabolites had similar systemic exposure. Pharmacodynamic assessment indicated decreased tumour perfusion in most patients. CONCLUSION: Regorafenib showed tolerability and antitumour activity in patients with metastatic CRC. This expanded-cohort phase I study provided the foundation for further clinical trials of regorafenib in this patient population.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Compostos de Fenilureia/administração & dosagem , Piridinas/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Neoplasias Colorretais/mortalidade , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Compostos de Fenilureia/efeitos adversos , Compostos de Fenilureia/farmacocinética , Piridinas/efeitos adversos , Piridinas/farmacocinética
5.
Br J Cancer ; 107(2): 280-6, 2012 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-22699824

RESUMO

BACKGROUND: BI 2536, a novel Polo-like kinase 1 inhibitor, was assessed in patients with unresectable advanced exocrine adenocarcinoma of the pancreas. METHODS: The study employed a two-stage design. Randomised first-line patients received BI 2536 200 mg on day 1 (n=43) or 60 mg on days 1-3 (n=43) every 21 days. Recruitment of second-line patients was planned for a second stage dependent on an interim analysis demonstrating ≥ 2 responses in the first 18 evaluable patients following 12 weeks of treatment and/or tumour control ≥ 12 weeks in 5 patients per schedule. Primary end point was objective response rate (ORR). RESULTS: By independent review, ORR was 2.3% (all partial) and 24.4% had stable disease as confirmed best response. The second stage was not initiated. Median overall and progression-free survivals were 149 (95% confidence interval (CI), 91-307) and 46 days (95% CI, 44-56). Most common drug-related adverse events were neutropenia (37.2%), leukopenia (29.1%), fatigue (29.1%) and nausea (22.1%); most common grade 3/4-related events were neutropenia (36.0%), leukopenia (27.9%) and thrombocytopenia (8.1%). CONCLUSION: Given the low ORR and poor survival, further development of BI 2536 monotherapy is not warranted in this population.


Assuntos
Adenocarcinoma/tratamento farmacológico , Proteínas de Ciclo Celular/antagonistas & inibidores , Neoplasias Pancreáticas/tratamento farmacológico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Pteridinas/uso terapêutico , Adenocarcinoma/enzimologia , Adenocarcinoma/metabolismo , Idoso , Proteínas de Ciclo Celular/metabolismo , Estudos de Coortes , Intervalos de Confiança , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Pteridinas/efeitos adversos , Pteridinas/farmacocinética , Quinase 1 Polo-Like
6.
Ann Oncol ; 22(2): 301-6, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20624784

RESUMO

BACKGROUND: Safety data for combining bevacizumab, everolimus, or lapatinib with anthracycline- and taxane-based neoadjuvant chemotherapy for breast cancer are limited. PATIENTS AND METHODS: The neoadjuvant GeparQuinto trial investigates the addition of (i) bevacizumab to four cycles epirubicin/cyclophosphamide (EC) followed by four cycles docetaxel (Taxotere) in patients with human epithelial growth factor receptor (HER)2-negative tumors, (ii) everolimus to weekly paclitaxel in patients with HER2-negative tumors not responding to EC ± bevacizumab, and (iii) lapatinib instead of trastuzumab to EC-docetaxel in patients with HER2-positive tumors to improve the rate of pathological complete response. Tolerable dose, need for supportive treatments, and early signals for toxic effect were evaluated in a planned safety analysis of 270 patients. RESULTS: Treatment with chemotherapy plus bevacizumab, everolimus, or lapatinib was discontinued in 23.0%, 25.8%, and 34.5% compared with chemotherapy alone or plus trastuzumab in 19.4%, 24.1%, 3.2%, respectively. More leukopenia, infections, mucositis, and hypertension but less edema was observed by adding bevacizumab; a trend toward more thrombocytopenia, leukopenia, skin changes, and hyperlipidemia by adding everolimus; and more diarrhea, skin changes, and hot flushes but no cardiac events by substituting trastuzumab by lapatinib. CONCLUSIONS: Adding bevacizumab and everolimus to chemotherapy appeared feasible. Lapatinib at 1250 mg resulted in an increased rate of treatment discontinuations and was subsequently dose reduced to 1000 mg.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Quinazolinas/uso terapêutico , Sirolimo/análogos & derivados , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bevacizumab , Quimioterapia Adjuvante , Everolimo , Feminino , Humanos , Lapatinib , Quinazolinas/administração & dosagem , Quinazolinas/efeitos adversos , Sirolimo/administração & dosagem , Sirolimo/efeitos adversos , Sirolimo/uso terapêutico
7.
Int J Clin Pharmacol Ther ; 48(10): 670-7, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20875373

RESUMO

OBJECTIVES: Polyisoprenylated acylphloroglucinols have recently emerged as antitumoral agents. This study aims at elucidating the antiretroviral activity of two such compounds which were isolated from Caribbean propolis: 7-epi-nemorosone and plukenetione A, the structure of which is based on an adamantane moiety. Plukenetione A is for the first time shown to have antiretroviral activity. MATERIAL AND METHODS: The isolation of both small molecules was carried out using RP-HPLC. Their antiretroviral activity was studied based on lentiviral particles produced in HEK293T cells from the SIV-based vector VLDBH; their cytotoxicity was monitored by MTT proliferation assay. The antiviral activity of 7-epi-nemorosone was studied in CEMx174-SEAP infected with the HIV-1-strain pNL4.3wt. Reverse transcriptase inhibition was determined by a standard two-step RT-PCR using MMLV RT. RESULTS: 7-epi-nemorosone and plukenetione A were found to be potent antilentiviral agents in the employed system, inhibiting viral infection at concentrations below 1 µM/2 µM, respectively. Whereas 7-epi-nemorosone was not able to inhibit the reverse transcriptase in vitro (IC50 > 25 µM), plukenetione A effectively inhibited its enzymatic activity at an IC50 of 1.75 µM. CONCLUSIONS: Despite 7-epi-nemorosone and plukenetione A sharing some structural core elements, the mechanism of action involved in their antiretroviral activity seems to be different. We propose that 7-epi-nemorosone inhibits the viral replication by interrupting the Akt/PKB signaling cascade, as was demonstrated previously in various cell lines. Since plukenetione A effectively inhibits the enzymatic activity of MMLV reverse transcriptase at concentrations that show antilentiviral activity, we suggest that this small molecule acts by interfering with the enzyme's catalytic site.


Assuntos
Antivirais/farmacologia , Benzofenonas/farmacologia , Lentivirus/efeitos dos fármacos , Compostos Policíclicos/farmacologia , Própole/química , Benzofenonas/química , Região do Caribe , Células Cultivadas , HIV-1/efeitos dos fármacos , Humanos , Compostos Policíclicos/química
8.
Breast ; 45: 22-28, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30822621

RESUMO

BACKGROUND: This multicenter, double-blind phase II study assessed the antitumor activity and toxicity profile of docetaxel with the antiangiogenic multikinase inhibitor sorafenib or matching placebo as a first-line treatment in patients with metastatic or locally advanced HER2-negative breast cancer. PATIENTS AND METHODS: Patients were randomized 1:1 to receive docetaxel 100 mg/m2 on day 1 every 3 weeks in combination with sorafenib 400 mg bid or placebo on days 2-18 of each cycle until tumor progression, or unacceptable toxicity. Sorafenib/placebo could be continued at the investigator's discretion if docetaxel was stopped due to toxicity. Primary endpoint was progression free survival (PFS). RESULTS: From October 2008 to December 2013, 102 patients were randomized; 98 patients were evaluable. The trial was prematurely terminated due to slow accrual. Due to increased toxicity the dose of docetaxel was reduced to 75 mg/m2 and an increasing sorafenib dosing schedule was implemented as part of a protocol amendment. The addition of sorafenib to docetaxel did not improve PFS (8.2 vs. 7.3 months for docetaxel/placebo; HR 0.84, log rank p = 0.43), but led to higher rates of early treatment discontinuation. There were no statistically significant differences between sorafenib dosing schedules. CONCLUSIONS: Addition of sorafenib to taxane-based first-line chemotherapy in patients with metastatic breast cancer failed to improve PFS and resulted in increased toxicity.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Docetaxel/administração & dosagem , Sorafenibe/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/metabolismo , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Receptor ErbB-2/metabolismo , Resultado do Tratamento
9.
Br J Cancer ; 99(10): 1579-85, 2008 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-19002179

RESUMO

Telatinib (BAY 57-9352) is an orally available, small-molecule inhibitor of vascular endothelial growth factor receptors 2 and 3 (VEGFR-2/-3) and platelet-derived growth factor receptor beta tyrosine kinases. In this multicentre phase I dose escalation study, 71 patients with refractory solid tumours were enroled into 14 days on/7 days off (noncontinuous dosing) or continuous dosing groups to receive telatinib two times daily (BID). Hypertension (23%) and diarrhoea (7%) were the most frequent study drug-related adverse events of CTC grade 3. The maximum-tolerated dose was not reached up to a dose of 1500 mg BID continuous dosing. Telatinib was rapidly absorbed with median t(max) of 3 hours or less. Geometric mean C(max) and AUC(0-12) increased in a less than dose-proportional manner and plateaued in the 900-1500 mg BID dose range. Two renal cell carcinoma patients reached a partial response. Tumour blood flow measured by contrast-enhanced magnetic resonance imaging and sVEGFR-2 plasma levels decreased with increasing AUC(0-12) of telatinib. Telatinib is safe and well tolerated up to a dose of 1500 mg BID continuous dosing. Based on pharmacokinetic and pharmacodynamic criteria, 900 mg telatinib BID continuously administered was selected as the recommended phase II dose.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Antineoplásicos/administração & dosagem , Neoplasias/tratamento farmacológico , Piridazinas/administração & dosagem , Piridinas/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Br J Cancer ; 98(12): 1959-65, 2008 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-18506148

RESUMO

In this study, we investigated the kinetics of oxaliplatin-DNA adduct formation in white blood cells of cancer patients in relation to efficacy as well as oxaliplatin-associated neurotoxicity. Thirty-seven patients with various solid tumours received 130 mg m(-2) oxaliplatin as a 2-h infusion. Oxaliplatin-DNA adduct levels were measured in the first cycle using adsorptive stripping voltammetry. Platinum concentrations were measured in ultrafiltrate and plasma using a validated flameless atomic absorption spectrometry method. DNA adduct levels showed a characteristic time course, but were not correlated to platinum pharmacokinetics and varied considerably among individuals. In patients showing tumour response, adduct levels after 24 and 48 h were significantly higher than in nonresponders. Oxaliplatin-induced neurotoxicity was more pronounced but was not significantly different in patients with high adduct levels. The potential of oxaliplatin-DNA adduct measurements as pharmacodynamic end point should be further investigated in future trials.


Assuntos
Antineoplásicos/sangue , Adutos de DNA/sangue , Leucócitos/metabolismo , Neoplasias/sangue , Compostos Organoplatínicos/sangue , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacologia , Humanos , Compostos Organoplatínicos/efeitos adversos , Compostos Organoplatínicos/farmacologia , Oxaliplatina
11.
Chirurg ; 79(7): 689-95; quiz 696, 2008 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-18584137

RESUMO

Despite the growing array of sophisticated diagnostic tools for establishing a diagnosis of human neoplasia, 2-6% of all cancer patients still present metastatic cancer of which detailed investigations fail to identify the primary anatomic site. The site is found in less than 25% of patients before death and frequently goes undiscovered at post-mortem examination. At the time of first diagnosis with carcinoma of unknown primary site, usually more than 80% of patients present with dissemination. Prognosis depends on the site(s) involved and is unaffected by whether the primary site is ever found. Node dissection may be curative for patients with metastases to peripheral lymph nodes. Objective long-term response is possible in combination with chemotherapy in patients with small-cell malignancies, peritoneal carcinomatosis (in women), or poorly differentiated carcinomas involving external lymph nodes, mediastinum, or retroperitoneum but without metastases to viscera or bone. Toxic therapies are recommended only for palliation of symptoms and maintaining quality of life support in patients with good functional status. Patients should be encouraged to participate in clinical trials for novel therapies.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Primárias Desconhecidas/tratamento farmacológico , Antineoplásicos/toxicidade , Diagnóstico Diferencial , Seguimentos , Humanos , Neoplasias Primárias Desconhecidas/diagnóstico , Neoplasias Primárias Desconhecidas/etiologia , Neoplasias Primárias Desconhecidas/patologia , Prognóstico
12.
Mol Cell Biol ; 20(11): 3977-87, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10805740

RESUMO

Topoisomerase I cleavage complexes can be induced by a variety of DNA damages and by the anticancer drug camptothecin. We have developed a ligation-mediated PCR (LM-PCR) assay to analyze replication-mediated DNA double-strand breaks induced by topoisomerase I cleavage complexes in human colon carcinoma HT29 cells at the nucleotide level. We found that conversion of topoisomerase I cleavage complexes into replication-mediated DNA double-strand breaks was only detectable on the leading strand for DNA synthesis, which suggests an asymmetry in the way that topoisomerase I cleavage complexes are metabolized on the two arms of a replication fork. Extension by Taq DNA polymerase was not required for ligation to the LM-PCR primer, indicating that the 3' DNA ends are extended by DNA polymerase in vivo closely to the 5' ends of the topoisomerase I cleavage complexes. These findings suggest that the replication-mediated DNA double-strand breaks generated at topoisomerase I cleavage sites are produced by replication runoff. We also found that the 5' ends of these DNA double-strand breaks are phosphorylated in vivo, which suggests that a DNA 5' kinase activity acts on the double-strand ends generated by replication runoff. The replication-mediated DNA double-strand breaks were rapidly reversible after cessation of the topoisomerase I cleavage complexes, suggesting the existence of efficient repair pathways for removal of topoisomerase I-DNA covalent adducts in ribosomal DNA.


Assuntos
Dano ao DNA , Replicação do DNA , DNA Topoisomerases Tipo I/metabolismo , DNA Ribossômico/metabolismo , Camptotecina/farmacologia , DNA/biossíntese , DNA de Cadeia Simples , Inibidores Enzimáticos/farmacologia , Células HT29 , Humanos , Cinética , Família Multigênica , Fosforilação , Inibidores da Topoisomerase I
13.
Eur J Cancer ; 42(4): 548-56, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16426838

RESUMO

In this analysis of the safety and efficacy of BAY 43-9006 (sorafenib) -- a novel, oral multi-kinase inhibitor with effects on tumour and its vasculature -- pooled data were obtained from four phase I dose-escalation trials. Time to progression (TTP) was compared in patients with/without grade 2 skin toxicity/diarrhoea. Grade 3 hand-foot skin reactions (HFS; 8%) and diarrhoea (6%) were common. At the recommended 400mg bid dose for phase II/III trials (RDP), 15% of patients experienced grade 2/3 HFS, and 24% experienced grade 2/3 diarrhoea. Sorafenib induced stable disease for 6 months in 12% of patients (6% stabilized for 1 year). Patients receiving sorafenib doses at or close to the RDP, who experienced skin toxicity/diarrhoea, had a significantly increased TTP compared with patients without such toxicity (P < 0.05). Sorafenib was well tolerated at the RDP, and induced sustained disease stabilization, particularly in patients with skin toxicity/diarrhoea.


Assuntos
Antineoplásicos/efeitos adversos , Benzenossulfonatos/efeitos adversos , Toxidermias/etiologia , Exantema/induzido quimicamente , Neoplasias/tratamento farmacológico , Piridinas/efeitos adversos , Administração Oral , Adolescente , Adulto , Idoso , Benzenossulfonatos/administração & dosagem , Ensaios Clínicos Fase I como Assunto , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Niacinamida/análogos & derivados , Compostos de Fenilureia , Piridinas/administração & dosagem , Sorafenibe , Resultado do Tratamento
16.
Urologe A ; 45(5): 614-9, 2006 May.
Artigo em Alemão | MEDLINE | ID: mdl-16710679

RESUMO

Carcinoma of unknown primary is common, accounting for 2-6% of all cancer patients. The primary site is found in less than 25% of patients before death and frequently goes undiscovered at postmortem examination. At the time point of first diagnosis of CUP syndrome, usually more than 80% of the patients present a disseminated situation. Prognosis depends on the involved site and is unaffected by whether or not the primary site is ever found. For patients presenting with metastasis to peripheral lymph nodes, node dissection may be curative. In patients with small cell malignancies, peritoneal carcinomatosis (in women), poorly differentiated carcinomas involving external lymph nodes, mediastinum, or retroperitoneum, but without metastases to viscera or bone, objective long-term responses are possible with combination chemotherapy. For all other patients, toxic therapies are recommended only for patients with good functional status, for palliation of symptoms when they develop, and for continuous support of the quality of life.


Assuntos
Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Primárias Desconhecidas/diagnóstico , Neoplasias Primárias Desconhecidas/tratamento farmacológico , Cuidados Paliativos/métodos , Neoplasias Urogenitais/tratamento farmacológico , Neoplasias Urogenitais/secundário , Ensaios Clínicos como Assunto , Humanos , Recidiva Local de Neoplasia/prevenção & controle , Guias de Prática Clínica como Assunto , Padrões de Prática Médica , Qualidade de Vida , Síndrome , Assistência Terminal/métodos , Neoplasias Urogenitais/diagnóstico
17.
Biochim Biophys Acta ; 1400(1-3): 83-105, 1998 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-9748515

RESUMO

DNA topoisomerase I is essential for cellular metabolism and survival. It is also the target of a novel class of anticancer drugs active against previously refractory solid tumors, the camptothecins. The present review describes the topoisomerase I catalytic mechanisms with particular emphasis on the cleavage complex that represents the enzyme's catalytic intermediate and the site of action for camptothecins. Roles of topoisomerase I in DNA replication, transcription and recombination are also reviewed. Because of the importance of topoisomerase I as a chemotherapeutic target, we review the mechanisms of action of camptothecins and the other topoisomerase I inhibitors identified to date.


Assuntos
Camptotecina/farmacologia , DNA Topoisomerases Tipo I/fisiologia , Antineoplásicos/farmacologia , Camptotecina/uso terapêutico , DNA/metabolismo , Resistência a Medicamentos/genética , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Substâncias Intercalantes/química , Substâncias Intercalantes/farmacologia , Modelos Moleculares , Estrutura Molecular , Compostos Policíclicos/química , Compostos Policíclicos/farmacologia , Inibidores da Topoisomerase I
18.
Leukemia ; 8(5): 780-5, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-7514246

RESUMO

Deficiency of deoxycytidine kinase (dCK) activity represents one possible cause of resistance to cytosine arabinoside (ara-C). Mutations of the dCK gene have recently been shown to be responsible for dCK deficiency and increased resistance in vitro. In order to define the relevance of this mechanism in vivo, we analyzed the dCK gene in 16 adult patients with relapsed/refractory acute myeloid leukemia (AML) and clinical resistance to standard-dose and/or high-dose ara-C. Southern blot analysis using genomic DNA from peripheral blood or bone marrow samples containing > or = 70% leukemic blasts and agarose gel electrophoresis of cDNA obtained by RT-PCR did not reveal gross rearrangements of the dCK gene. Sequencing of the dCK coding region showed point mutations in seven patients. Besides two silent mutations (or RFLPs) in codon 42 and 86, base pair mutations resulting in amino acid replacements were found in five patients affecting codon 20, 93, 98, 99, and 154, respectively. dCK cDNA clones from three patients with > or = 50% of sequenced clones revealing the specific base pair alteration were bacterially expressed in E. coli and analyzed for dCK activity. Normal enzyme activity was found in two patients (codon 20 and 98), and a complete loss of activity in one patient (codon 99). We conclude that structural alteration of the coding region of the dCK gene represents one possible mechanism for ara-C resistance in vivo, but, considering the frequency of this event, other mechanisms may play a more important role for clinical resistance to ara-C in patients with AML.


Assuntos
Citarabina/uso terapêutico , Desoxicitidina Quinase/genética , Leucemia Mieloide Aguda/genética , Adulto , Idoso , Sequência de Bases , Southern Blotting , Códon , Análise Mutacional de DNA , Desoxicitidina Quinase/metabolismo , Resistência a Medicamentos/genética , Feminino , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/enzimologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação Puntual , Reação em Cadeia da Polimerase , RNA Neoplásico/análise , DNA Polimerase Dirigida por RNA
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA