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1.
Cancer Chemother Pharmacol ; 78(3): 541-5, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27422303

RESUMO

OBJECTIVES: AUY922 is a novel heat shock protein inhibitor with preclinical activity in pancreatic cancer. This phase II study evaluated the efficacy of AUY922 in patients with advanced pancreatic cancer previously treated with chemotherapy. METHODS: In this single-arm, Simon two-stage phase II trial, patients with metastatic or locally advanced pancreatic ductal adenocarcinoma who had progressed on at least one line of chemotherapy and were of good performances status (ECOG 0 or 1) were treated with AUY922 at a dose of 70 mg/m(2) IV weekly. The primary endpoint was disease control rate (objective response and stable disease ≥16 weeks). RESULTS: Twelve patients were accrued, all of whom received treatment. At least possibly related ≥grade 3 adverse events included fatigue (8 %) and AST elevation (8 %). Ten patients were evaluable for response with 1 (10 %) having stable disease and 9 (90 %) progressive disease. The median progression-free survival was 1.6 months, and the median overall survival was 2.9 months. CONCLUSIONS: AUY922 was not associated with significant efficacy in previously treated patients with advanced pancreatic cancer.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/administração & dosagem , Carcinoma Ductal Pancreático/tratamento farmacológico , Isoxazóis/administração & dosagem , Resorcinóis/administração & dosagem , Adenocarcinoma/patologia , Adulto , Idoso , Antineoplásicos/efeitos adversos , Carcinoma Ductal Pancreático/patologia , Intervalo Livre de Doença , Feminino , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Humanos , Isoxazóis/efeitos adversos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Resorcinóis/efeitos adversos , Taxa de Sobrevida , Resultado do Tratamento
2.
Br J Cancer ; 113(6): 864-71, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26325106

RESUMO

BACKGROUND: Hypoxia is thought to be an adverse feature of pancreatic cancer, but direct measurement in patients is technically challenging. To address this, we characterised the intra/interpatient heterogeneity of hypoxia in surgical specimens from patients who received the 2-nitroimidazole tracer pimonidazole pre-operatively. METHODS: Pimondazole was given intravenously 16-20 h before pancreatectomy, and the extent and intratumoral heterogeneity of hypoxia determined by image analysis applied to multiple tissue blocks stained by immunohistochemistry. Intra/interpatient heterogeneity was estimated by variance component analysis. RESULTS: Pimonidazole staining was analysed in 10 tumours. The extent of labelling varied amongst patients (0-26%), with a broader range of hypoxia in the epithelial (1-39%) compared with the stromal (1-13%) compartments. Variance component analysis demonstrated greater inter- than intrapatient variability of hypoxia, and that multiple (4-5) tumour sections are required to provide a consistent evaluation of its extent in individual tumours. CONCLUSIONS: There is significant intra- and intertumoral heterogeneity of hypoxia in pancreatic cancers, and these do not appear to be generally more hypoxic than other cancer types. This study establishes the feasibility to assess hypoxia in pancreatic cancer patients using pimonidazole, but questions the reliability of measurements made using a single tissue section.


Assuntos
Carcinoma Ductal Pancreático/metabolismo , Hipóxia Celular , Indicadores e Reagentes/metabolismo , Nitroimidazóis/metabolismo , Neoplasias Pancreáticas/metabolismo , Adulto , Análise de Variância , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/cirurgia , Estudos de Viabilidade , Feminino , Humanos , Imuno-Histoquímica , Indicadores e Reagentes/administração & dosagem , Injeções Intravenosas , Masculino , Nitroimidazóis/administração & dosagem , Pâncreas/metabolismo , Pancreatectomia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Pré-Medicação , Viés de Seleção
3.
Br J Cancer ; 113(3): 425-32, 2015 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-26180923

RESUMO

BACKGROUND: Germline mutations of the BRCA tumour suppressors have been associated with increased risk of pancreatic cancer. Clinical evidence suggests that these patients may be more sensitive to treatment with cisplatin. As the frequency of germline BRCA mutations is low, definitive experimental data to support the clinical observations are still missing. METHODS: We tested gemcitabine and cisplatin sensitivity of four BRCA1 and BRCA2 mutant and three BRCA1 and BRCA2 wild-type (WT) patient-derived pancreatic cancer xenografts. RESULTS: We observed treatment sensitivity to gemcitabine and cisplatin in the BRCA WT and mutant models. The BRCA1 and BRCA2 mutant xenografts were significantly more sensitive to cisplatin although these models also showed sensitivity to gemcitabine. The BRCA1 and BRCA2 WT models showed sensitivity to gemcitabine but not cisplatin. Treatment sensitivity in the xenograft models closely resembled treatment response in the corresponding patients. DISCUSSION: We have characterised a panel of xenografts derived from pancreatic cancer patients carrying germline BRCA mutations, and shown that their genetic features resemble the patient donor. Our results support further clinical testing of treatment regimens combining gemcitabine and platinum drugs in this patient population, as well as preclinical research aiming to identify mechanisms of cisplatin resistance in BRCA mutant pancreatic cancers.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Genes BRCA1 , Genes BRCA2 , Mutação em Linhagem Germinativa , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Cisplatino/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
4.
Br J Cancer ; 111(6): 1132-8, 2014 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-25072261

RESUMO

BACKGROUND: The BRCA1/2 proteins are involved in regulation of cellular proliferation by DNA damage repair via homologous recombination. Therefore, BRCA1/2 mutation carriers with pancreatic cancer may have distinct biologic outcomes. METHODS: Patients with BRCA1/2-associated pancreatic ductal adenocarcinoma (PDAC) diagnosed between January 1994 and December 2012 were identified from databases at three participating institutions. Clinical data were collected. Disease-free survival and overall survival (OS) were analysed. RESULTS: Overall, 71 patients with PDAC and BRCA1 (n=21), BRCA2 (n=49) or both (n=1) mutations were identified. Mean age at diagnosis was 60.3 years (range 33-83), 81.7% (n=58) had any family history of malignancy; 30% (n=21) underwent primary resection. Out of 71 participants, 12 received experimental therapy; one patient had missing data, these 13 cases were excluded from OS analysis. Median OS for 58 patients was 14 months (95% CI 10-23 months). Median OS for patients with stage 1/2 disease has not been reached with 52% still alive at 60 months. Median OS for stage 3/4 was 12 months (95% CI 6-15). Superior OS was observed for patients with stage 3/4 treated with platinum vs those treated with non-platinum chemotherapies (22 vs 9 months; P=0.039). CONCLUSION: Superior OS was observed for advanced-disease BRCA-associated PDAC with platinum exposure.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Carcinoma Ductal Pancreático/genética , Neoplasias Pancreáticas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/terapia , Cisplatino/administração & dosagem , Intervalo Livre de Doença , Feminino , Marcadores Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Estadiamento de Neoplasias , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/terapia , Taxa de Sobrevida
5.
Eur J Cancer ; 50(11): 1909-15, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24857345

RESUMO

BACKGROUND: Erlotinib induced skin toxicity has been associated with clinical benefit in several tumour types. This phase II study evaluated the efficacy of erlotinib, dose escalated to rash, in patients with advanced pancreatic cancer previously treated with gemcitabine. METHODS: Erlotinib was given at an initial dose of 150 mg/day, and the dose was escalated by 50mg every 2 weeks (to a maximum of 300 mg/day) until >grade 1 rash or other dose limiting toxicities occurred. Erlotinib pharmacokinetics were performed, and baseline tumour tissue was collected for mutational analysis and epidermal growth factor receptor (EGFR) expression. The primary end-point was the disease control rate (objective response and stable disease >8 weeks). RESULTS: Fifty-one patients were accrued, and 49 received treatment. Dose-escalation to 200-300 mg of erlotinib was possible in 9/49 (18%) patients. The most common ⩾ grade 3 adverse events included fatigue (6%), rash (4%) and diarrhoea (4%). Thirty-seven patients were evaluable for response, and the best response was stable disease in 12 patients (32% (95% confidence interval (CI) 17-47%)). Disease control was observed in nine patients (24% (95% CI: 10-38%)). Median survival was 3.8 months, and 6 month overall survival rate was 32% (95% CI 19-47%). Mutational analysis and EGFR expression were performed on 29 patients, with 93% having KRAS mutations, none having EGFR mutations, and 86% expressing EGFR. Neither KRAS mutational status nor EGFR expression was associated with survival. CONCLUSIONS: Erlotinib dose escalated to rash was well tolerated but not associated with significant efficacy in non-selected patients with advanced pancreatic cancer.


Assuntos
Neoplasias Pancreáticas/tratamento farmacológico , Quinazolinas/administração & dosagem , Adulto , Idoso , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacocinética , Desoxicitidina/farmacologia , Relação Dose-Resposta a Droga , Toxidermias/etiologia , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/biossíntese , Cloridrato de Erlotinib , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/farmacocinética , Quinazolinas/efeitos adversos , Quinazolinas/farmacocinética , Gencitabina
6.
Clin Oncol (R Coll Radiol) ; 26(4): 203-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24462333

RESUMO

AIMS: To determine the efficacy of induction gemcitabine followed by biweekly gemcitabine concurrent with radiotherapy for locally advanced pancreatic cancer. MATERIALS AND METHODS: Between March 2001 and August 2009, 90 patients with unresectable (78) or resected (12) pancreatic cancer were treated with a standard treatment policy of induction gemcitabine (seven doses of weekly gemcitabine at 1000 mg/m(2)) followed by concurrent radiotherapy (52.5 Gy) and biweekly gemcitabine (40 mg/m(2)). RESULTS: After induction gemcitabine, 17.8% of patients did not proceed to chemoradiotherapy, due to either disease progression, performance status deterioration or gemcitabine toxicity. Of the patients who received chemoradiotherapy, 68.9% completed the course of 52.5 Gy, whereas 79.7% received more than 45 Gy. Chemoradiotherapy was stopped early due to treatment toxicity in 22.9% of patients. On intention to treat analysis, the median overall survival was 12.7 months in the locally advanced group and 18.2 months in the resected group. On multivariate analysis for the unresectable patients, a larger gross tumour volume was a significant poor prognostic factor for overall survival and local progression-free survival. CONCLUSION: This large series confirms, in a standard practice setting, similar efficacy and tolerability of treatment as previously reported in our phase I-II study. The benefit to patients with a gross tumour volume >48 cm(3) may be limited.


Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/radioterapia , Radiossensibilizantes/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimiorradioterapia , Desoxicitidina/administração & dosagem , Intervalo Livre de Doença , Esquema de Medicação , Feminino , Humanos , Quimioterapia de Indução , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Gencitabina , Neoplasias Pancreáticas
7.
Curr Oncol ; 19(3): 169-74, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22670096

RESUMO

The annual Eastern Canadian Colorectal Cancer Consensus Conference was held in Ottawa, Ontario, October 22-23, 2010. Health care professionals involved in the care of patients with colorectal cancer participated in presentation and discussion sessions for the purpose of developing the recommendations presented here. This consensus statement addresses current issues in the management of colorectal cancer, such as the use of epidermal growth factor inhibitors in metastatic colon cancer, the benefit of calcium and magnesium with oxaliplatin chemotherapy, the role of microsatellites in treatment decisions for stage II colon cancer, the staging and treatment of rectal cancer, and the management of colorectal and metastatic pancreatic cancers.

8.
Leukemia ; 25(6): 945-52, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21403650

RESUMO

This phase I/II study evaluated imatinib as a c-kit inhibitor combined with mitoxantrone, etoposide and cytarabine therapy for patients with primary refractory or relapsed c-kit+ acute myeloid leukemia (AML). Imatinib was escalated through three dose levels in successive six patient cohorts. The combination was well tolerated up to 400 mg/day imatinib. Of 21 patients treated at this dose, 13 (62%) achieved complete response (CR), 7 (33%) were non-responders and one died during induction. The CR rate was 80% in patients with standard-risk karyotype versus 33% in patients with adverse karyotype. The CR rate for primary non-responders was 6/14 (43%) versus 7/7 (100%) for relapsed patients. AML blasts from peripheral blood were assayed for phosphorylated Akt (pAkt) and phosphorylated ERK (pERK) by flow cytometry before to and after imatinib dosing. Of eight patients achieving CR with reinduction, seven demonstrated marked (≥60%) pAkt inhibition with imatinib therapy. In contrast, all the six non-responders to reinduction demonstrated <60% pAkt inhibition (P=0.005). There was no correlation between pERK inhibition and response to therapy. These results indicate that lack of pAkt inhibition in vivo is associated with resistance to reinduction therapy using this regimen. Further studies using agents that are able to inhibit Akt more effectively are warranted.


Assuntos
Leucemia Mieloide Aguda/tratamento farmacológico , Piperazinas/administração & dosagem , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-kit , Pirimidinas/administração & dosagem , Terapia de Salvação/métodos , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Benzamidas , Feminino , Humanos , Mesilato de Imatinib , Leucemia Mieloide Aguda/patologia , Masculino , Pessoa de Meia-Idade , Fosforilação , Prognóstico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Indução de Remissão/métodos , Resultado do Tratamento
10.
Br J Cancer ; 100(8): 1267-76, 2009 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-19319133

RESUMO

The phosphatidylinositol-3-kinase (PI3K)/Akt signalling pathway is frequently deregulated in pancreatic cancers, and is believed to be an important determinant of their biological aggression and drug resistance. NVP-BEZ235 is a novel, dual class I PI3K/mammalian target of rapamycin (mTor) inhibitor undergoing phase I human clinical trials. To simulate clinical testing, the effects of NVP-BEZ235 were studied in five early passage primary pancreatic cancer xenografts, grown orthotopically. These tumours showed activated PKB/Akt, and increased levels of at least one of the receptor tyrosine kinases that are commonly activated in pancreatic cancers. Pharmacodynamic effects were measured following acute single doses, and anticancer effects were determined in separate groups following chronic drug exposure. Acute oral dosing with NVP-BEZ235 strongly suppressed the phosphorylation of PKB/Akt, followed by recovery over 24 h. There was also inhibition of Ser235/236 S6 ribosomal protein and Thr37/46 4E-BP1, consistent with the effects of NVP-BEZ235 as a dual PI3K/mTor inhibitor. Chronic dosing with 45 mg kg(-1) of NVP-BEZ235 was well tolerated, and produced significant tumour growth inhibition in three models. These results predict that agents targeting the PI3K/Akt/mTor pathway might have anticancer activity in pancreatic cancer patients, and support the testing of combination studies involving chemotherapy or other molecular targeted agents.


Assuntos
Imidazóis/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Inibidores de Fosfoinositídeo-3 Quinase , Quinolinas/uso terapêutico , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Animais , Antineoplásicos/uso terapêutico , Diferenciação Celular , Criança , Inibidores Enzimáticos/uso terapêutico , Humanos , Imuno-Histoquímica , Camundongos , Camundongos SCID , Neoplasias Pancreáticas/patologia , Proteínas Quinases/efeitos dos fármacos , Proteínas Quinases/metabolismo , Serina-Treonina Quinases TOR , Transplante Heterólogo
11.
Br J Cancer ; 99(7): 1074-82, 2008 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-18797457

RESUMO

Eph receptors constitute the largest family of receptor tyrosine kinases in the human genome. EphA2 is one prominent member that is overexpressed and functionally altered in many invasive cancers, including pancreatic cancer. Dasatinib, which is a multi-targeted kinase inhibitor mainly developed for Bcr-Abl and Src family kinases, has recently been shown to have significant activity against EphA2. As selective small molecule EphA2 inhibitors are not currently available, we investigated the therapeutic potential to target EphA2 by dasatinib in pancreatic cancer cell lines. Using in vitro kinase assays, we found that EphA2 receptor tyrosine kinase was inhibited directly by dasatinib in a dose-dependent manner. Stimulation with ephrinA1 produced rapid increases of EphA2 phosphorylation that were inhibited by dasatinib, although the effects on activation of downstream signalling differed among the pancreatic cancer cell lines. Dasatinib also inhibited ligand-induced binding of EphA2 to the ubiquitin ligase Cbl, and the internalisation and degradation of EphA2, suggesting that these processes are dependent on kinase activity. Treatment with dasatinib decreased EphA2 phosphorylation in BxPC-3 xenografts, suggesting that dasatinib might have activity in pancreatic cancer due to EphA2 inhibition, besides its effects on Src.


Assuntos
Neoplasias Pancreáticas/patologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Receptor EphA2/antagonistas & inibidores , Transdução de Sinais , Tiazóis/farmacologia , Animais , Linhagem Celular Tumoral , Dasatinibe , Humanos , Masculino , Camundongos , Camundongos SCID , Microscopia de Fluorescência , Neoplasias Pancreáticas/enzimologia , Receptor EphA2/metabolismo
12.
Br J Cancer ; 95(9): 1148-54, 2006 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-17031397

RESUMO

Standard cytotoxic treatments for neuroendocrine tumours have been associated with limited activity and remarkable toxicity. A phase II study was designed to evaluate the efficacy, safety and pharmacodynamics of temsirolimus in patients with advanced neuroendocrine carcinoma (NEC). Thirty-seven patients with advanced progressive NEC received intravenous weekly doses of 25 mg of temsirolimus. Patients were evaluated for tumour response, time to progression (TTP), overall survival (OS) and adverse events (AE). Twenty-two archival specimens, as well as 13 paired tumour biopsies obtained pretreatment and after 2 weeks of temsirolimus were assessed for potential predictive and correlative markers. The intent-to-treat response rate was 5.6% (95% CI 0.6-18.7%), median TTP 6 months and 1-year OS rate 71.5%. The most frequent drug-related AE of all grades as percentage of patients were: fatigue (78%), hyperglycaemia (69%) and rash/desquamation (64%). Temsirolimus effectively inhibited the phosphorylation of S6 (P=0.02). Higher baseline levels of pmTOR (phosphorylated mammalian target of rapamycin) (P=0.01) predicted for a better response. Increases in pAKT (P=0.041) and decreases in pmTOR (P=0.048) after treatment were associated with an increased TTP. Temsirolimus appears to have little activity and does not warrant further single-agent evaluation in advanced NEC. Pharmacodynamic analysis revealed effective mTOR pathway downregulation.


Assuntos
Carcinoma Neuroendócrino/tratamento farmacológico , Sirolimo/análogos & derivados , Adulto , Idoso , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Tumor Carcinoide/tratamento farmacológico , Tumor Carcinoide/metabolismo , Tumor Carcinoide/patologia , Carcinoma Neuroendócrino/metabolismo , Carcinoma Neuroendócrino/patologia , Progressão da Doença , Exantema/induzido quimicamente , Fadiga/induzido quimicamente , Feminino , Seguimentos , Humanos , Hiperglicemia/induzido quimicamente , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Fosforilação/efeitos dos fármacos , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína S6 Ribossômica/metabolismo , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Análise de Sobrevida , Serina-Treonina Quinases TOR , Resultado do Tratamento
13.
Br J Cancer ; 94(8): 1136-43, 2006 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-16570047

RESUMO

Erlotinib (Tarceva, OSI-774), a potent epidermal growth factor receptor tyrosine kinase inhibitor (EGFR), was evaluated in a phase II study to assess its activity in patients with metastatic colorectal cancer. In all, 38 patients with metastatic colorectal cancer were treated with erlotinib at a continuous daily oral dose of 150 mg. Radiological evaluation was carried out every 8 weeks and tumour biopsies were performed before treatment and on day 8. Of 31 evaluable patients, 19 (61%) had progressive disease and 12 (39%) had stable disease (s.d.). The median time to progression for those patients having s.d. was 123 days (range 108-329 days). The most common adverse events were rash in 34 patients and diarrhoea in 23 patients. Correlative studies were conducted to investigate the effect of erlotinib on downstream signalling. Tumour tissue correlations were based on usable tissue from eight match paired tumour samples pre- and on therapy, and showed a statistically significant decrease in the median intensity of both pEGFR (P=0.008) and phospho-extracellular signal-regulated kinase (ERK) (P=0.008) a week after commencement of treatment. No other statistically significant change in tumour markers was observed. Erlotinib was well tolerated with the most common toxicities being rash and diarrhoea. More than one-third of evaluable patients had s.d. for a minimum of 8 weeks. Correlative studies showed a reduction in phosphorylated EGFR and ERK in tumour tissue post-treatment.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Colorretais/terapia , Quinazolinas/uso terapêutico , Adulto , Idoso , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Quimioterapia Adjuvante , Neoplasias Colorretais/sangue , Neoplasias Colorretais/patologia , Progressão da Doença , Intervalo Livre de Doença , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Cloridrato de Erlotinib , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Quinazolinas/efeitos adversos , Quinazolinas/farmacocinética , Recidiva , Fatores de Risco , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Taxa de Sobrevida , Resultado do Tratamento
14.
Clin Oncol (R Coll Radiol) ; 17(2): 91-5, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15830570

RESUMO

AIMS: Intergroup study 0116 (INT-0116) showed an 11% absolute improvement in 3-year survival with post-operative radiochemotherapy for gastric cancer, but reported 33% severe acute GI toxicity using conventional simulation with large fields. We adapted the treatment using conformal radiotherapy techniques and assessed toxicity and outcome in 20 consecutive patients. METHODS: A conformal radiotherapy technique previously developed for gastric lymphoma was adapted to treat the target volume defined in INT-0116. The five-field plan used a large anterior field, plus asymmetrically matched upper AP:PA fields and lower lateral fields. Consecutive patients with ECOG PS 0-2 and stage IB-IV non-metastatic gastric cancer were treated with 5-FU (425 mg/m2 daily x 5 days) and leucovorin (20 mg/m2 daily x 5 days) for one cycle prior to and two cycles following concurrent radiation (45 Gy/25 fractions) with identical drug dosages on the first 4 and last 3 days of radiation. Acute toxicity was prospectively recorded weekly using RTOG and NCI common toxicity criteria. Patient charts were reviewed in November 2003 and late toxicity and outcome were recorded. RESULTS: Nineteen of 20 patients completed radiotherapy and 14 completed all chemotherapy cycles. One patient died of neutropenic sepsis. Maximum acute toxicity [grade (number)] was: 5(1), 4(0), 3(4), 2(10), 1(4), 0(1). There were two grade 1 late toxicities. Two-year overall survival is 70% (95% confidence interval: 50-90). CONCLUSIONS: Conformal radiotherapy may improve acute toxicity (25% grade 3 or greater toxicity as compared with 41% reported in INT-0116). Survival is comparable to that achieved in the INT-0116 treatment arm (approximately 60% at 2 years). INT-0116 results can be achieved outside a study setting; however, further efforts to improve treatment efficacy and minimize toxicity are warranted.


Assuntos
Neoplasias Gástricas/radioterapia , Adulto , Idoso , Antimetabólitos Antineoplásicos/uso terapêutico , Terapia Combinada , Feminino , Fluoruracila/uso terapêutico , Humanos , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Radioterapia Conformacional , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/cirurgia , Análise de Sobrevida
15.
Br J Cancer ; 91(6): 1166-73, 2004 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-15316562

RESUMO

Apurinic/apyrimidinic endonuclease (APE) is a key enzyme involved in DNA base excision repair (BER) that is often expressed at elevated levels in human cancers. Pancreatic cancer cells treated with the nucleoside analogue gemcitabine (2', 2'-difluoro-2'deoxycytidine) showed increases in APE/redox effector factor (ref-1) protein levels (approximately two-fold for Panc-1 and six-fold for MiaPaCa-2), with corresponding increases in endonuclease activity. These results suggested that the activation of APE/ref-1 might be an adaptive response that contributes to gemcitabine resistance by facilitating BER. To test this hypothesis, we examined the effects of disrupting APE/ref-1 using antisense on gemcitabine toxicity. Antisense oligonucleotides decreased protein levels three-fold in MiaPaCa-2 and five-fold in Panc-1 in comparison to controls, associated with reduced endonuclease activity. Combination treatments with antisense oligonucleotides and gemcitabine partially suppressed the increase in APE/ref-1 activity seen in cells exposed to gemcitabine alone. While clonogenic assays showed only slight decreases in colony formation in cells treated with either antisense oligonucleotides or gemcitabine alone, the combination with APE/ref-1 antisense resulted in a 2-log enhancement of gemcitabine toxicity in Panc-1 cells. Overall these findings suggest that APE/ref-1 plays a significant role in gemcitabine resistance in some pancreatic cancer cells, and support the further investigation of novel treatments that target this protein.


Assuntos
Antimetabólitos Antineoplásicos/toxicidade , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Desoxicitidina/análogos & derivados , Desoxicitidina/toxicidade , Oligonucleotídeos Antissenso/farmacologia , Transporte Biológico , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/efeitos dos fármacos , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/isolamento & purificação , Resistencia a Medicamentos Antineoplásicos , Citometria de Fluxo , Humanos , Cinética , Oligonucleotídeos Antissenso/farmacocinética , Neoplasias Pancreáticas , Transfecção , Gencitabina
16.
Ann Oncol ; 15(5): 770-4, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15111345

RESUMO

BACKGROUND: Unresectable biliary tract cancer has a very poor prognosis. A combination of weekly gemcitabine plus continuous infusional 5-fluorouracil (5-FU) (GEM/CVI 5-FU) was evaluated as therapy for this cancer. PATIENTS AND METHODS: The charts of 27 patients with advanced biliary tract adenocarcinoma treated with GEM/CVI 5-FU at the Princess Margaret Hospital were evaluated for response, survival and toxicity. The treatment consisted of a 30-min infusion of gemcitabine at 900 mg/m(2) on days 1, 8 and 15 of a 28-day cycle plus 5-FU given via a peripherally inserted central line at 200 mg/m(2)/day continuously for 21 days, every 28 days. RESULTS: Objective responses were observed in nine patients (33%; 95% confidence interval 17% to 54%). An additional eight patients (30%) achieved stable disease for a median of 4 months (range 2.3-11). Median time to progression and overall survival were 3.7 and 5.3 months, respectively. Direct chemotherapy-related toxicity was mild, with only 11% grade > or =3 myelosuppression. Central venous catheter complications were common (26%). There were no treatment-related deaths. CONCLUSIONS: This study shows that GEM/CVI 5-FU is active and well tolerated in advanced and metastatic biliary tract cancers.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias dos Ductos Biliares/tratamento farmacológico , Ductos Biliares Intra-Hepáticos/patologia , Colangiocarcinoma/tratamento farmacológico , Desoxicitidina/análogos & derivados , Neoplasias da Vesícula Biliar/tratamento farmacológico , Adulto , Idoso , Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/patologia , Desoxicitidina/administração & dosagem , Progressão da Doença , Esquema de Medicação , Feminino , Fluoruracila/administração & dosagem , Neoplasias da Vesícula Biliar/patologia , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento , Gencitabina
17.
Cancer Chemother Pharmacol ; 54(1): 49-56, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15034755

RESUMO

PURPOSE: To determine whether gamma-glutamyl transpeptidase (gamma-GT) is involved in the maintenance of elevated cysteine levels in cervical carcinoma. METHODS: Four cervical carcinoma cell lines were tested in vitro for cysteine accumulation and gamma-GT levels. The highest and lowest gamma-GT-expressing cell lines were used in in vivo experiments to determine the effect of gamma-GT inhibition on cysteine levels. RESULTS: Treatment of a series of cervical carcinoma cell lines with acivicin decreased intracellular cysteine concentrations. Cysteine depletion was evident in Me180 cells which had the greatest levels of gamma-GT activity, and had a more pronounced cysteine decrease in medium with glutathione and cysteine concentrations simulating the in vivo situation. Also investigated were the effects of inhibition of gamma-GT activity on intracellular cysteine levels in xenografts grown in severe combined immunodeficient (SCID) mice. With the use of 35 mg/kg of acivicin, gamma-GT activity decreased to basal levels of detection in both tumour types and significant decreases in cysteine levels were seen in the high gamma-GT-expressing tumours (Me180). Thus, inhibition of gamma-GT activity may have therapeutic potential in high-expressing cancers. CONCLUSIONS: In tumours and cell lines with elevated levels of gamma-GT activity, inhibition of this enzyme led to decreases of cysteine levels.


Assuntos
Carcinoma de Células Escamosas/fisiopatologia , Cisteína/análise , Neoplasias do Colo do Útero/fisiopatologia , gama-Glutamiltransferase/farmacologia , Animais , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Isoxazóis/farmacologia , Camundongos , Camundongos SCID , Transplante Heterólogo , gama-Glutamiltransferase/antagonistas & inibidores
18.
Cytometry A ; 51(1): 1-6, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12500299

RESUMO

BACKGROUND: Repopulation of clonogenic tumor cells appears to increase during fractionated radiation treatment and is recognized as an important factor affecting local control. Given the longer intervals between cycles and longer total duration of treatment, the impact of repopulation is likely to be greater after chemotherapy. METHODS: We assessed tumor cell repopulation with the proliferative marker Ki-67 in 21 patients with ovarian carcinoma who received initial chemotherapy. Paraffin slides were evaluated from the diagnostic biopsy and from tumor obtained at debulking surgery after chemotherapy. Immunohistochemistry using the MIB-1 antibody was performed on the paired samples and analyzed with a digital imaging device linked to a color camera mounted on a transmitted-light microscope. The ratio of Ki-67 positive to all nuclei was used as a proliferative index and compared for pre- and postchemotherapy specimens. RESULTS: All patients received platinum-based chemotherapy and most showed a response to treatment. The median duration between last chemotherapy and debulking surgery was 33 days (range, 22-50 days). Four (19%) of 21 patients showed an increased proliferative index after chemotherapy, and the remainder showed a decrease (n = 12) or no significant change (n = 5). CONCLUSIONS: Our results did not suggest an increase in proliferation of tumor cells after this type of chemotherapy in the majority of patients with ovarian cancer.


Assuntos
Antineoplásicos/efeitos adversos , Carcinoma/patologia , Resistencia a Medicamentos Antineoplásicos , Recidiva Local de Neoplasia/induzido quimicamente , Recidiva Local de Neoplasia/patologia , Neoplasias Ovarianas/patologia , Biomarcadores Tumorais , Carboplatina/efeitos adversos , Carcinoma/tratamento farmacológico , Carcinoma/fisiopatologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Núcleo Celular/patologia , Células Clonais/citologia , Células Clonais/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Antígeno Ki-67 , Recidiva Local de Neoplasia/fisiopatologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/fisiopatologia , Paclitaxel/efeitos adversos , Projetos Piloto
20.
Clin Colorectal Cancer ; 2(2): 93-101, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12453323

RESUMO

Most patients with colorectal cancer (CRC) who have failed initial 5-fluorouracil (5-FU) chemotherapy have worsening of disease-related symptoms (DRS) and quality of life (QOL). Irinotecan has a reported response rate of 10%-20% in such patients. The aim of this phase II trial was to prospectively determine the palliative benefit of irinotecan utilizing DRS as primary endpoints of response. Patients had advanced CRC refractory to 5-FU with at least 1 DRS defined as (1) Karnofsky performance status (KPS) 60%-80%, (2) baseline analgesic use > or = 10 mg morphine/day (or equivalent), or (3) disease-related pain score > 1 cm on a 10-cm linear analogue self-assessment (LASA) scale. Patients received irinotecan 125 mg/m2 weekly for 4 weeks on an every-6-weeks schedule. The primary endpoint was palliative response defined as > or = 50% decrease in pain score or analgesic usage, or 10% increase in KPS, from baseline for 4 weeks. QOL was assessed by the European Organization for Research and Treatment of Cancer Quality-of-Life Questionnaire Core 30 (EORTC QLQ-C30) version 2 instrument. A total of 65 patients were entered onto the study. Median baseline parameters were KPS 70%, analgesic score 11 mg/day, and pain score 2.4 cm. A palliative response was achieved in 27 patients (42%), improvement in pain score predominated. LASA and EORTC QLQ-C30 instruments showed parallel changes in DRS. The radiological response rate was 11% (complete responses and partial responses, n = 46); 23 patients achieved stable disease. Median overall survival was 7.2 months. Irinotecan provides a rate of palliative benefit higher than the radiological response rate. Patients-oriented palliative endpoints can be useful in assessing the benefit of agents in early-phase clinical trials.


Assuntos
Camptotecina/análogos & derivados , Camptotecina/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/mortalidade , Resistencia a Medicamentos Antineoplásicos , Fluoruracila , Cuidados Paliativos/métodos , Qualidade de Vida , Adulto , Idoso , Canadá , Neoplasias Colorretais/patologia , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Humanos , Irinotecano , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Probabilidade , Estudos Prospectivos , Análise de Sobrevida , Resultado do Tratamento
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