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1.
Invest New Drugs ; 37(1): 76-86, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29667134

RESUMO

Purpose DFP-10917 is a novel deoxycytidine analog with a unique mechanism of action. Brief exposure to high concentrations of DFP-10917 inhibits DNA polymerase resulting in S-phase arrest, while prolonged exposure to DFP-10917 at low concentration causes DNA fragmentation, G2/M-phase arrest, and apoptosis. DFP-10917 demonstrated activity in tumor xenografts resistant to other deoxycytidine analogs. Experimental design Two phase I studies assessed the safety, pharmacokinetic, pharmacodynamic and preliminary efficacy of DFP-10917. Patients with refractory solid tumors received DFP-10917 continuous infusion 14-day on/7-day off and 7-day on/7-day off. Enrollment required age > 18 years, ECOG Performance Status 0-2 and adequate organ function. Results 29 patients were dosed in both studies. In 14-day infusion, dose-limiting toxicities (DLT) consisting of febrile neutropenia and thrombocytopenia occurred at 4.0 mg/m2/day. At 3.0 mg/m2/day, 3 patients experienced neutropenia in cycle 2. The dose of 2.0 mg/m2/day was well tolerated in 6 patients. In 7-day infusion, grade 4 neutropenia was DLT at 4.0 mg/m2/day. The maximum tolerated dose was 3 mg/m2/day. Other toxicities included nausea, vomiting, diarrhea, neutropenia, and alopecia. Eight patients had stable disease for >12 weeks. Paired comet assays performed for 7 patients showed an increase in DNA strand breaks at day 8. Pharmacokinetic data showed dose-proportionality for steady-state concentration and AUC of DFP-10917 and its primary metabolite. Conclusion Continuous infusion of DFP-10917 is feasible and well tolerated with myelosuppression as main DLT. The recommended doses are 2.0 mg/m2/day and 3.0 mg/m2/day on the 14-day and 7-day continuous infusion schedules, respectively. Preliminary activity was suggested. Pharmacodynamic data demonstrate biological activity at the tested doses.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/farmacocinética , Desoxicitidina/análogos & derivados , Isoflurofato/química , Neoplasias/tratamento farmacológico , Adulto , Idoso , Antineoplásicos/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/farmacocinética , Desoxicitidina/farmacologia , Esquema de Medicação , Feminino , Seguimentos , Humanos , Infusões Intravenosas , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Neoplasias/patologia , Prognóstico , Distribuição Tecidual
2.
Oncologist ; 24(7): 921-932, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30552157

RESUMO

BACKGROUND: First-line treatment for metastatic colorectal cancer (mCRC) typically entails a biologic such as bevacizumab (BEV) with 5-fluorouracil/leucovorin/oxaliplatin (FOLFOX) or 5-fluorouracil/leucovorin/irinotecan (FOLFIRI). STEAM (NCT01765582) assessed the efficacy of BEV plus FOLFOX/FOLFIRI (FOLFOXIRI), administered concurrently (cFOLFOXIRI-BEV) or sequentially (sFOLFOXIRI-BEV, FOLFOX-BEV alternating with FOLFIRI-BEV), versus FOLFOX-BEV for mCRC. PATIENTS AND METHODS: Patients with previously untreated mCRC (n = 280) were randomized 1:1:1 to cFOLFOXIRI-BEV, sFOLFOXIRI-BEV, or FOLFOX-BEV and treated with 4-6-month induction followed by maintenance. Coprimary objectives were overall response rate (ORR; first-line cFOLFOXIRI-BEV vs. FOLFOX-BEV) and progression-free survival (PFS; pooled first-line cFOLFOXIRI-BEV and sFOLFOXIRI-BEV vs. FOLFOX-BEV). Secondary/exploratory objectives included overall survival (OS), liver resection rates, biomarker analyses, and safety. RESULTS: ORR was 72.0%, 72.8%, and 62.1% and median PFS was 11.9, 11.4, and 9.5 months with cFOLFOXIRI-BEV, sFOLFOXIRI-BEV, and FOLFOX-BEV, respectively. OS was similar between arms. ORR between cFOLFOXIRI-BEV and FOLFOX-BEV did not significantly differ (p = .132); thus, the primary ORR endpoint was not met. cFOLFOXIRI-BEV and sFOLFOXIRI-BEV numerically improved ORR and PFS, regardless of RAS status. Median PFS was higher with pooled concurrent and sequential FOLFOXIRI-BEV versus FOLFOX-BEV (11.7 vs. 9.5 months; hazard ratio, 0.7; 90% confidence interval, 0.5-0.9; p < .01). Liver resection rates were 17.2% (cFOLFOXIRI-BEV), 9.8% (sFOLFOXIRI-BEV), and 8.4% (FOLFOX-BEV). Grade ≥ 3 treatment-emergent adverse events (TEAEs) were observed in 91.2% (cFOLFOXIRI-BEV), 86.7% (sFOLFOXIRI-BEV), and 85.6% (FOLFOX-BEV) of patients, with no increase in serious chemotherapy-associated TEAEs. CONCLUSION: cFOLFOXIRI-BEV and sFOLFOXIRI-BEV were well tolerated with numerically improved ORR, PFS, and liver resection rates versus FOLFOX-BEV, supporting triplet chemotherapy plus BEV as a first-line treatment option for mCRC. IMPLICATIONS FOR PRACTICE: The combination of first-line FOLFIRI with FOLFOX and bevacizumab (concurrent FOLFOXIRI-BEV) improves clinical outcomes in patients with metastatic colorectal cancer (mCRC) relative to FOLFIRI-BEV or FOLFOX-BEV, but it is thought to be associated with increased toxicity. Alternating treatment of FOLFOX and FOLFIRI (sequential FOLFOXIRI-BEV) could improve tolerability. In the phase II STEAM trial, which is the largest study of FOLFOXIRI-BEV in patients in the U.S., it was found that both concurrent and sequential FOLFOXIRI-BEV are active and well tolerated in patients with previously untreated mCRC, supporting the use of these regimens as potential first-line treatment options for this population.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Adolescente , Adulto , Idoso , Bevacizumab/administração & dosagem , Neoplasias Colorretais/patologia , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Irinotecano/administração & dosagem , Leucovorina/administração & dosagem , Neoplasias Hepáticas/secundário , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Oxaliplatina/administração & dosagem , Prognóstico , Taxa de Sobrevida , Adulto Jovem
3.
Invest New Drugs ; 36(5): 895-902, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29948357

RESUMO

Background DFP-10917 is a cytotoxic deoxycytidine analogue that causes DNA fragmentation, G2/M-phase arrest, and apoptosis. This agent has been shown to have antitumor activity against colorectal cancer (CRC) in preclinical studies and to be tolerable in patients. The purpose of our phase II trial was to evaluate the safety, efficacy and pharmacogenomics of DFP-10917 as well as DNA damage studies in patients with advanced CRC refractory to cytotoxic chemotherapy. Methods In this single-arm, Simon two-stage, phase II trial, patients with chemotherapy-refractory advanced CRC received 2.0 mg/m2/day DFP-10917 via 14-day continuous infusion. Enrollment criteria included age ≥ 18 years, Eastern Cooperative Oncology Group status of 0 or 1, and adequate organ function. The primary endpoint was 3-month progression-free survival, defined as the proportion of patients who did not have progressive disease or death within 3 months of starting therapy. All patients who received any amount of DFP-10917 were included in the safety analysis. DNA damage study was assessed by comet assay. Results Of 28 patients initially enrolled, 26 received DFP-10917. Three patients (12%) were progression free at 3 months. The median progression-free survival was 1.3 months (95% confidence interval, 1.3-1.6 months). There were no complete or partial responses. Most patients (n = 20, 77%) had progressive disease, and only six (23%) had stable disease at any time. The trial was terminated according to the pre-planned stopping rule. The most frequent (≥5%) medication-related grade 3 or higher adverse events were neutropenia (n = 10, 38%), fatigue (n = 4, 15%), anemia (n = 3, 12%), and leukopenia (n = 3, 12%). DNA strand-breaks were detected after infusion (medians of % tail intensity were 2.89 and 12.64 on day 1 and day 15, respectively, p < 0.001, sign test). Conclusion Overall, single-agent DFP-10917 did not show meaningful antitumor activity in chemotherapy-refractory advanced CRC. The safety profile of DFP-10917 was tolerable and similar to that observed in earlier clinical studies.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Desoxicitidina/administração & dosagem , Adulto , Idoso , Anemia/induzido quimicamente , Antineoplásicos/efeitos adversos , Neoplasias Colorretais/genética , Dano ao DNA , Desoxicitidina/efeitos adversos , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Fadiga/induzido quimicamente , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Infusões Intravenosas , Leucopenia/induzido quimicamente , Masculino , Pessoa de Meia-Idade
4.
Oncologist ; 22(12): 1427-e129, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28935773

RESUMO

LESSONS LEARNED: The addition of the heat shock protein 27 (Hsp27)-targeting antisense oligonucleotide, apatorsen, to a standard first-line chemotherapy regimen did not result in improved survival in unselected patients with metastatic pancreatic cancer.Findings from this trial hint at the possible prognostic and predictive value of serum Hsp27 that may warrant further investigation. BACKGROUND: This randomized, double-blinded, phase II trial evaluated the efficacy of gemcitabine/nab-paclitaxel plus either apatorsen, an antisense oligonucleotide targeting heat shock protein 27 (Hsp27) mRNA, or placebo in patients with metastatic pancreatic cancer. METHODS: Patients were randomized 1:1 to Arm A (gemcitabine/nab-paclitaxel plus apatorsen) or Arm B (gemcitabine/nab-paclitaxel plus placebo). Treatment was administered in 28-day cycles, with restaging every 2 cycles, until progression or intolerable toxicity. Serum Hsp27 levels were analyzed at baseline and on treatment. The primary endpoint was overall survival (OS). RESULTS: One hundred thirty-two patients were enrolled, 66 per arm. Cytopenias and fatigue were the most frequent grade 3/4 treatment-related adverse events for both arms. Median progression-free survival (PFS) and OS were 2.7 and 5.3 months, respectively, for arm A, and 3.8 and 6.9 months, respectively, for arm B. Objective response rate was 18% for both arms. Patients with high serum level of Hsp27 represented a poor-prognosis subgroup who may have derived modest benefit from addition of apatorsen. CONCLUSION: Addition of apatorsen to chemotherapy does not improve outcomes in unselected patients with metastatic pancreatic cancer in the first-line setting, although a trend toward prolonged PFS and OS in patients with high baseline serum Hsp27 suggests this therapy may warrant further evaluation in this subgroup.


Assuntos
Albuminas/administração & dosagem , Desoxicitidina/análogos & derivados , Proteínas de Choque Térmico HSP27/antagonistas & inibidores , Proteínas de Choque Térmico HSP27/sangue , Oligonucleotídeos Antissenso/administração & dosagem , Paclitaxel/administração & dosagem , Neoplasias Pancreáticas/tratamento farmacológico , Adulto , Idoso , Albuminas/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Paclitaxel/efeitos adversos , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/patologia , Prognóstico , Resultado do Tratamento , Gencitabina
5.
Cancer Chemother Pharmacol ; 68(6): 1431-8, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21479635

RESUMO

PURPOSE: The gemcitabine and oxaliplatin (GEMOX) has yielded among the longest progression-free survival durations in patients with advanced pancreatic cancer (APC). We postulated that adding bevacizumab would increase the effectiveness of GEMOX. METHODS: Eligible patients had stage III or IV pancreatic cancer, ECOG PS 0-2, and no prior gemcitabine. Treatment included 1,000 mg/m(2) intravenous gemcitabine over 100 min on day 1, 10 mg/kg intravenous bevacizumab on day 1, and 100 mg/m(2) oxaliplatin given on day 2. Cycles were repeated every 2 weeks. CT imaging was performed every 6 weeks. RESULTS: Fifty patients were enrolled: 14 had stage III disease, the remainder stage IV. Median age was 59 years. Fourty-five patients were ECOG 0-1. The grade 3-4 toxicity rate was 94%; fatigue (47%) and nausea (40%) were frequent. One patient died after a bowel perforation; a second died of a CVA. The median PFS was 4.9 months; median survival was 11.9 months; 1 year survival was 42%. Locally advanced patients lived 12.8 months; metastatic patients lived 10.2 months. Patients developing grade 3 hypertension were more likely to have a radiologic response (P = .012); survival among the top and bottom quintiles of hypertension was 14.7 and 6.2 months, respectively. Survival correlated with baseline CA 19-9 (P = .004) and radiologic response. The overall response rate was 36%; 34% demonstrated stable disease. CONCLUSIONS: The GEMOX/bevacizumab regimen demonstrated an excellent median overall survival but did not meet our objective of a 14 month median survival. Toxicity was significant. We do not recommend further evaluation of this regimen.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bevacizumab , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Gencitabina
6.
BMC Cancer ; 10: 368, 2010 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-20630061

RESUMO

BACKGROUND: The phosphoinositide 3-kinase (PI3K)/Akt pathway is constitutively activated in pancreatic cancer and the mammalian target of rapamycin (mTOR) kinase is an important mediator for its signaling. Our recent in vitro studies suggest that prolonged exposure of pancreatic cancer cells to mTOR inhibitors can promote insulin receptor substrate-PI3K interactions and paradoxically increase Akt phosphorylation and cyclin D1 expression in pancreatic cancer cells (negative feedback loop). The addition of erlotinib to rapamycin can down-regulate rapamycin-stimulated Akt and results in synergistic antitumor activity with erlotinib in preclinical tumor models. METHODS: Two studies prospectively enrolled adult patients with advanced pancreatic cancer, Eastern Cooperative Oncology Group performance status 0-1, adequate hematologic, hepatic and renal parameters and measurable disease. In Study A, temsirolimus was administered intravenously at 25 mg weekly. In Study B, everolimus was administered orally at 30 mg weekly and erlotinib was administered at 150 mg daily. The primary endpoint in both studies was overall survival at 6 months. Secondary endpoints included time to progression, progression-free survival, overall survival, response rate, safety and toxicity. Pretreatment tumor biopsies were analyzed by immunofluorescence and laser scanning cytometry for the expression of pmTOR/mTOR, pAkt/Akt, pErk/Erk, pS6, p4EBP-1 and PTEN. RESULTS: Five patients enrolled in Study A; Two patients died within a month (rapid disease progression and hemorrhagic stroke, respectively). One patient developed dehydration and another developed asthenia. Sixteen patients enrolled in Study B.: 12 males, all ECOG PS = 1. Median cycles = 1 (range 1-2). Grade 4 toxicity: hyponatremia (n = 1), Grade 3: diarrhea (n = 1), cholangitis (n = 3), hyperglycemia (n = 1), fatigue (n = 1). Grade 2: pneumonia (n = 2), dehydration (n = 2), nausea (n = 2), neutropenia (n = 1), mucositis (n = 2) & rash (n = 2). Four patients were hospitalized. Progressive disease occurred in 15 and 1 was non-evaluable. Pretreatment biopsies revealed a higher pAkt/Akt ratio in tumor specimens that in nonmalignant pancreatic tissue. No such trends were noted for the other biomarkers. CONCLUSIONS: Neither study with mTOR inhibitors demonstrated objective responses or disease stability. The negative feedback loop resulting from mTOR inhibition may account for the disease progression and toxicity noted in these studies. Future strategies should aim for a broader targeting of the PI3K pathway in pancreatic cancer. STUDY A: NCT 0075647. STUDY B: NCT00640978.


Assuntos
Adenocarcinoma/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias Pancreáticas/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica , Receptores ErbB/antagonistas & inibidores , Cloridrato de Erlotinib , Everolimo , Feminino , Imunofluorescência , Humanos , Técnicas Imunoenzimáticas , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Fosforilação , Prognóstico , Estudos Prospectivos , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinazolinas/uso terapêutico , Transdução de Sinais , Sirolimo/análogos & derivados , Sirolimo/uso terapêutico , Taxa de Sobrevida , Serina-Treonina Quinases TOR/antagonistas & inibidores
7.
Cancer Invest ; 26(8): 794-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18798063

RESUMO

TAS-102 is a novel formulation of the fluorinated pyrimidine analogue trifluorothymidine (FTD) with an inhibitor of thymidine phosphorylase. The purpose of this study was to determine the MTD and DLT for TAS-102 administered three times a day on days 1-5 and 8-12 every 4 weeks. Fifteen patients were enrolled with two patients experiencing dose-limiting fatigue and granulocytopenia at the first dose level (80 mg/m2/day). Granulocytopenia was the primary toxicity: 7 patients experienced grade 3 or 4 granulocytopenia with the first course. No responses were noted, but nine patients demonstrated prolonged stable disease in this heavily pretreated 5-FU refractory population.


Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Neoplasias/tratamento farmacológico , Trifluridina/administração & dosagem , Uracila/análogos & derivados , Adenocarcinoma/tratamento farmacológico , Administração Oral , Adulto , Idoso , Antimetabólitos Antineoplásicos/efeitos adversos , Antimetabólitos Antineoplásicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Esquema de Medicação , Combinação de Medicamentos , Feminino , Gastroenteropatias/induzido quimicamente , Doenças Hematológicas/induzido quimicamente , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Pirrolidinas , Timina , Trifluridina/efeitos adversos , Trifluridina/uso terapêutico , Uracila/administração & dosagem , Uracila/efeitos adversos , Uracila/uso terapêutico
8.
Cancer ; 113(8): 2046-52, 2008 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-18756532

RESUMO

BACKGROUND: To the authors' knowledge, there is no established second-line chemotherapy for patients with pancreatic cancer who have received gemcitabine-based therapy. A phase 2 trial was conducted to explore the efficacy of capecitabine and oxaliplatin (XELOX) in patients with advanced pancreatic cancer previously who were treated with gemcitabine. METHODS: Patients aged < or = 65 years who had an Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0 to 1 received oxaliplatin at a dose of 130 mg/m(2) given on Day 1 and capecitabine at a dose of 1000 mg/m(2) twice daily for 14 days. For patients aged >65 years or with an ECOG PS of 2, the oxaliplatin dose was 110 mg/m(2) on Day 1 and the capecitabine dose was 750 mg/m(2) twice daily for 14 days. The treatment was repeated every 3 weeks. Tumor measurements were performed every 9 weeks and the primary study objective was 6-month overall survival. RESULTS: The study enrolled 41 patients. Of the 39 evaluable patients, 1 patient had a partial response and 10 patients demonstrated stable disease. The Kaplan-Meier estimate of the overall median survival was 23 weeks (95% confidence interval [95% CI], 17.0-31.0 weeks). Progression-free survival was 9.9 weeks (95% CI, 9.6-14.5 weeks). The 6-month and 1-year survival rates were 44% (95% CI, 31%-62%) and 21% (95% CI, 11%-38%), respectively. The most common grade 3-4 nonhematologic toxicity was fatigue (toxicity was graded using the National Cancer Institute Common Toxicity Criteria [version 2.0]). CONCLUSIONS: The combination of capecitabine and oxaliplatin is active in gemcitabine-pretreated patients with advanced pancreatic cancer, especially in patients with a good PS and those who have responded to first-line chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Idoso , Capecitabina , Carcinoma/mortalidade , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Intervalo Livre de Doença , Feminino , Fluoruracila/análogos & derivados , Fluoruracila/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Oxaloacetatos , Neoplasias Pancreáticas/mortalidade , Análise de Sobrevida
9.
J Clin Oncol ; 26(21): 3487-95, 2008 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-18640929

RESUMO

PURPOSE: We conducted a phase II trial of preoperative gemcitabine and cisplatin chemotherapy in addition to chemoradiation (Gem-Cis-XRT) and pancreaticoduodenectomy (PD) for patients with stage I/II pancreatic adenocarcinoma. PATIENTS AND METHODS: Chemotherapy consisted of gemcitabine (750 mg/m(2)) and cisplatin (30 mg/m(2)) given every 2 weeks for four doses. Chemoradiation consisted of four weekly infusions of gemcitabine (400 mg/m(2)) combined with radiation therapy (30 Gy in 10 fractions administered over 2 weeks) delivered 5 days per week. Patients underwent restaging 4 to 6 weeks after completion of chemoradiation and, in the absence of disease progression, were taken to surgery. RESULTS: The study enrolled 90 patients; 79 patients (88%) completed chemo-chemoradiation. Sixty-two (78%) of 79 patients were taken to surgery and 52 (66%) of 79 underwent PD. The median overall survival of all 90 patients was 17.4 months. Median survival for the 79 patients who completed chemo-chemoradiation was 18.7 months, with a median survival of 31 months for the 52 patients who underwent PD and 10.5 months for the 27 patients who did not undergo surgical resection of their primary tumor (P < .001). CONCLUSION: Preoperative Gem-Cis-XRT did not improve survival beyond that achieved with preoperative gemcitabine-based chemoradiation (Gem-XRT) alone. The longer preoperative interval required more durable biliary decompression (metal stents) but was not associated with local tumor progression. The gemcitabine-based chemoradiation platform is a reasonable foundation on which to build future phase II multimodality trials for stage I/II pancreatic cancer incorporating emerging systemic therapies.


Assuntos
Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Terapia Neoadjuvante/métodos , Neoplasias Pancreáticas/terapia , Cuidados Pré-Operatórios/métodos , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Terapia Combinada , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Pancreaticoduodenectomia , Radioterapia/efeitos adversos , Gencitabina
10.
Invest New Drugs ; 26(5): 445-54, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18528634

RESUMO

This study was designed to determine the safety and optimal dosing of TAS-102, a novel oral combination of alphaalphaalpha-trifluorothymidine (FTD) and an inhibitor of thymidine phoshorylase, in patients with solid tumors. Patients who met the eligibility criteria were treated with one of two different TAS-102 regimens: once per day on either days 1-5 and 8-12 every 4 weeks (schedule A) or days 1-5 every 3 weeks (schedule B). The primary objectives were the determination of the maximum tolerated dose, dose-limiting toxicities (DLTs), and recommended phase II dose. Pharmacokinetic analysis was conducted during courses 1 and 2. Sixty-three patients received a total of 172 courses of therapy with the median number of courses delivered on both schedules being 2. DLTs were observed in three patients on schedule A, 70 mg/m(2)/day (1) and 110 mg/m(2)/day (2); and in five patients on schedule B, 120 mg/m(2)/day (1), 170 mg/m(2)/day (2), 180 mg/m(2)/day (2). Granulocytopenia was the DLT in seven of the eight cases. The most frequent toxicities were nausea, fatigue, granulocytopenia, anemia, diarrhea, and abdominal pain. Twelve patients, 6 on schedule A and 6 on schedule B, were treated at the recommended phase II dose, with good tolerance. No objective responses were seen in this heavily pretreated, 5-FU-refractory population. The pharmacokinetic parameters of FTD are a T (max) of 0.53 to 3.15 h, t (1/2) of 1.46 to 4.20 h, volume of distribution of 0.0526 to 0.483 l/kg, and clearance of 0.0194 to 0.197 1/h/kg. The recommended phase II doses for TAS-102 are 100 mg/m(2)/day on schedule A and 160 mg/m(2)/day on schedule B. Future development of TAS-102 should focus upon multiple daily dosing schedules.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Trifluridina/uso terapêutico , Uracila/análogos & derivados , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Esquema de Medicação , Combinação de Medicamentos , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Pirrolidinas , Timina , Trifluridina/administração & dosagem , Trifluridina/efeitos adversos , Trifluridina/farmacocinética , Uracila/administração & dosagem , Uracila/efeitos adversos , Uracila/farmacocinética , Uracila/uso terapêutico
11.
J Pain Symptom Manage ; 34(3): 244-52, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17513082

RESUMO

Pancreatic cancer is a lethal disease characterized by multiple disease-related symptoms. Chemoradiation therapy is a standard of treatment for locally advanced pancreatic cancer. Although shown to prolong survival, there is little information about treatment-related symptoms or the palliative benefits of chemoradiation. We assessed symptoms of patients with locally advanced pancreatic cancer receiving chemoradiation to determine the prevalence, and co-occurrence, of symptoms and to identify the extent to which symptoms interfered with function. Forty-eight patients were treated with chemoradiation on a Phase I protocol. Patients received radiotherapy (50.4 Gy in 28 fractions), capecitabine (median dose 825 mg/m(2) twice daily), and bevacizumab (2.5-10 mg/kg). Symptom severity and its interference with function were prospectively assessed (at presentation, during, and after chemoradiation) in 43 consenting patients using the M.D. Anderson Symptom Inventory. Results showed that 95% of patients reported at least one of the 13 symptoms assessed at presentation. The most commonly reported symptoms of moderate to severe (>or=5 on a 0-10 scale) intensity at presentation were lack of appetite (24%), pain (19%), fatigue (19%), and sleep disturbance (10%). We observed an increase in patients reporting moderate to severe fatigue, nausea, and sleep disturbance during chemoradiation. McNemar tests for paired binary observations showed the proportion of patients reporting moderate to severe symptoms significantly (P<0.001) decreased after chemoradiation at 94 days follow-up (lack of appetite=7%, pain=7%, fatigue=13%, sleep disturbance=7%). This study demonstrates the feasibility and usefulness of symptom assessment in chemoradiation protocols. Future studies with larger cohorts are needed to further characterize multiple symptoms associated with chemoradiation.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Apetite , Fadiga/epidemiologia , Fadiga/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/epidemiologia , Náusea/etiologia , Dor/epidemiologia , Dor/etiologia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/fisiopatologia , Prevalência , Transtornos do Sono-Vigília/epidemiologia , Transtornos do Sono-Vigília/etiologia
12.
Ann Surg Oncol ; 13(8): 1035-46, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16865597

RESUMO

With recent advances in pancreatic imaging and surgical techniques, a distinct subset of pancreatic tumors is emerging that blurs the distinction between resectable and locally advanced disease: tumors of "borderline resectability." In our practice, patients with borderline-resectable pancreatic cancer include those whose tumors exhibit encasement of a short segment of the hepatic artery, without evidence of tumor extension to the celiac axis, that is amenable to resection and reconstruction; tumor abutment of the superior mesenteric artery involving <180 degrees of the circumference of the artery; or short-segment occlusion of the superior mesenteric vein, portal vein, or their confluence with a suitable option available for vascular reconstruction because the veins are normal above and below the area of tumor involvement. With currently available surgical techniques, patients with borderline-resectable pancreatic head cancer are at high risk for a margin-positive resection. Therefore, our approach to these patients is to use preoperative systemic therapy and local-regional chemoradiation to maximize the potential for an R0 resection and to avoid R2 resections. In our experience, patients with favorable responses to preoperative therapy (radiographical evidence of tumor regression and improvement in serum tumor marker levels) are the subset of patients who have the best chance for an R0 resection and a favorable long-term outcome.


Assuntos
Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Cuidados Pré-Operatórios/métodos , Adulto , Biomarcadores Tumorais/sangue , Terapia Combinada , Feminino , Humanos , Fígado/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Pâncreas/irrigação sanguínea , Neoplasias Pancreáticas/terapia , Seleção de Pacientes
13.
Drugs ; 66(8): 1059-72, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16789792

RESUMO

Chemotherapy remains the mainstay of treatment for pancreatic cancer as most patients present with advanced disease, which precludes locoregional treatment. However, the efficacy of chemotherapy is limited. Gemcitabine is the only agent that improves symptoms and confers a modest survival advantage. Many combination therapy regimens have been studied in phase II settings. Eleven randomised phase III trials have been conducted to compare gemcitabine-containing regimens with gemcitabine monotherapy since gemcitabine became available clinically. The combination of gemcitabine plus capecitabine has demonstrated a survival advantage over gemcitabine, whereas gemcitabine plus oxaliplatin and gemcitabine plus cisplatin have shown improved progression-free survival or time to tumour progression but failed to demonstrate a survival advantage over gemcitabine. The search for effective therapy for advanced pancreatic cancer continues. Gemcitabine in combination with cytotoxic agents or molecular targeted agents hold promise.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Antimetabólitos Antineoplásicos/uso terapêutico , Ensaios Clínicos como Assunto , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Quimioterapia Combinada , Humanos , Gencitabina
14.
J Clin Oncol ; 24(13): 2065-72, 2006 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-16648507

RESUMO

PURPOSE: Chemotherapy before resection of hepatic colorectal metastases (CRM) may cause hepatic injury and affect postoperative outcome. PATIENTS AND METHODS: Four hundred six patients underwent hepatic resection of CRM between 1992 and 2005. Pathologic review of the nontumorous liver was performed using established criteria for steatosis, steatohepatitis, and sinusoidal injury. The effect of chemotherapy and liver injury on perioperative outcome was analyzed. RESULTS: One hundred fifty-eight patients (38.9%) received no preoperative chemotherapy, whereas 248 patients (61.1%) did. The median duration of chemotherapy was 16 weeks (range, 2 to 70 weeks). Chemotherapy consisted of fluoropyrimidine-based regimens (fluorouracil [FU] alone, 15.5%; irinotecan plus FU, 23.1%; and oxaliplatin plus FU, 19.5%) and other therapy (3.0%). On pathologic analysis, 36 patients (8.9%) had steatosis, 34 (8.4%) had steatohepatitis, and 22 (5.4%) had sinusoidal dilation. Oxaliplatin was associated with sinusoidal dilation compared with no chemotherapy (18.9% v 1.9%, respectively; P < .001; odds ratio [OR] = 8.3; 95% CI, 2.9 to 23.6). In contrast, irinotecan was associated with steatohepatitis compared with no chemotherapy (20.2% v 4.4%, respectively; P < .001; OR = 5.4; 95% CI, 2.2 to 13.5). Patients with steatohepatitis had an increased 90-day mortality compared with patients who did not have steatohepatitis (14.7% v 1.6%, respectively; P = .001; OR = 10.5; 95% CI, 2.0 to 36.4). CONCLUSION: Steatohepatitis is associated with an increased 90-day mortality after hepatic surgery. In patients with hepatic CRM, the chemotherapy regimen should be carefully considered because the risk of hepatotoxicity is significant.


Assuntos
Antineoplásicos/efeitos adversos , Neoplasias Colorretais/patologia , Fígado Gorduroso/etiologia , Neoplasias Hepáticas/secundário , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Terapia Combinada , Fígado Gorduroso/mortalidade , Feminino , Hepatectomia , Humanos , Fígado/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade
15.
Cancer Res ; 66(7): 3773-81, 2006 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-16585204

RESUMO

The proteasome inhibitor bortezomib (formerly known as PS-341) recently received Food and Drug Administration approval for the treatment of multiple myeloma, and its activity is currently being evaluated in solid tumors. Bortezomib triggers apoptosis in pancreatic cancer cells, but the mechanisms involved have not been fully elucidated. Here, we show that pancreatic cancer cells exposed to bortezomib formed aggregates of ubiquitin-conjugated proteins ("aggresomes") in vitro and in vivo. Bortezomib-induced aggresome formation was determined to be cytoprotective and could be disrupted using histone deacetylase (HDAC) 6 small interfering RNA or chemical HDAC inhibitors, which resulted in endoplasmic reticulum stress and synergistic levels of apoptosis in vitro and in an orthotopic pancreatic cancer xenograft model in vivo. Interestingly, bortezomib did not induce aggresome formation in immortalized normal human pancreatic epithelial cells in vitro or in murine pancreatic epithelial cells in vivo. In addition, these cells did not undergo apoptosis following treatment with bortezomib, suberoylanilide hydroxamic acid, or the combination, showing tumor selectivity. Taken together, our study shows that inhibition of aggresome formation can strongly potentiate the efficacy of bortezomib and provides the foundation for clinical trials of bortezomib in combination with HDAC inhibitors for the treatment of pancreatic cancer.


Assuntos
Apoptose/efeitos dos fármacos , Ácidos Borônicos/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Pirazinas/farmacologia , Animais , Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Ácidos Borônicos/administração & dosagem , Bortezomib , Inibidores de Histona Desacetilases , Histona Desacetilases/genética , Humanos , Ácidos Hidroxâmicos/administração & dosagem , Ácidos Hidroxâmicos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/patologia , Inibidores de Proteases/farmacologia , Inibidores de Proteassoma , Pirazinas/administração & dosagem , RNA Interferente Pequeno/genética , Vorinostat , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Cancer Res ; 66(7): 3802-12, 2006 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-16585207

RESUMO

The epidermal growth factor receptor (EGFR) is considered an important therapeutic target in pancreatic cancer, but it is currently impossible to identify those patients who are most likely to benefit from EGFR-directed therapy. We examined the biological effects of the EGFR tyrosine kinase inhibitor gefitinib (ZD1839, Iressa) in a panel of nine human pancreatic cancer cell lines. The drug strongly inhibited DNA synthesis and induced low levels of apoptosis at clinically relevant concentrations in a subset of three of the lines (L3.6pl, BxPC3, and Cfpac1). Sensitivity to gefitinib correlated directly with ligand [transforming growth factor-alpha (TGF-alpha)] expression (r(2) = 0.71, P = 0.004) but not with surface EGFR expression. The gefitinib-sensitive cells displayed constitutive baseline EGFR phosphorylation, whereas the gefitinib-resistant cells did not. Exposure to gefitinib or a small interfering RNA construct specific for TGF-alpha reversed the constitutive EGFR phosphorylation and downstream target [extracellular signal-regulated kinases (ERK), AKT] phosphorylation in the gefitinib-sensitive cells but had no effects on ERK or AKT phosphorylation in gefitinib-resistant cells. Baseline EGFR phosphorylation was lower in a subclone of L3.6pl selected for low TGF-alpha expression, and these cells were also resistant to gefitinib-mediated growth inhibition. Gefitinib blocked the growth of tumor xenografts derived from L3.6pl cells but had no effect on the growth of tumors derived from EGFR-independent MiaPaCa-2 cells. Together, our data show that TGF-alpha expression identifies a subset of human pancreatic cancer cells that is dependent on EGFR signaling in vitro and in vivo. Quantification of TGF-alpha expression may therefore represent an effective means of identifying EGFR-responsive primary tumors.


Assuntos
Antineoplásicos/farmacologia , Receptores ErbB/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Quinazolinas/farmacologia , Fator de Crescimento Transformador alfa/biossíntese , Animais , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/agonistas , Receptores ErbB/biossíntese , Gefitinibe , Humanos , Masculino , Camundongos , Camundongos Nus , Neoplasias Pancreáticas/patologia , Fosforilação , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Cancer ; 106(10): 2241-6, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16598762

RESUMO

BACKGROUND: Both irinotecan and oxaliplatin are active agents in the treatment of patients with metastatic colorectal cancer, and there is a strong preclinical rationale for combining these 2 agents. Therefore, a Phase II trial was designed and conducted to determine the efficacy and tolerability of combined irinotecan and oxaliplatin given every 3 weeks to patients with metastatic colorectal cancer. METHODS: Patients with previously untreated metastatic colorectal cancer received irinotecan at a dose of 175 mg/m2 and oxaliplatin at a dose of 130 mg/m2, both given intravenously every 3 weeks. Objective responses were evaluated every 2 courses and were confirmed at least 4 weeks after the initial determination. RESULTS: Fifty-five patients were enrolled and treated in the current trial. Of the 53 patients whose responses were evaluable, 18 (34%) achieved a partial response, 27 (51%) had stable disease, and 8 (15%) developed disease progression as their best response to the treatment. The intent-to-treat median survival for all patients was 16.4 months and the time to progression was 4.8 months. All 55 patients were available for toxicity analysis (according to version 2.0 of the National Cancer Institute Common Toxicity Criteria). The most common Grade 3-4 toxic effect was neutropenia, which was reported to occur in 22 patients (40%). CONCLUSIONS: The combination of irinotecan and oxaliplatin appears to be safe and active when used to treat patients with metastatic colorectal cancer. Treatment results with this regimen were similar to those reported for other combined frontline chemotherapy regimens for colorectal cancer. When this particular regimen wa used, neutropenia was found to be the predominant toxicity.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/secundário , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Adenocarcinoma/mortalidade , Adulto , Idoso , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Humanos , Irinotecano , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Medição de Risco , Método Simples-Cego , Análise de Sobrevida , Resultado do Tratamento
18.
J Clin Oncol ; 24(16): 2505-12, 2006 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-16636341

RESUMO

PURPOSE: This phase II randomized discontinuation trial evaluated the effects of sorafenib (BAY 43-9006), an oral multikinase inhibitor targeting the tumor and vasculature, on tumor growth in patients with metastatic renal cell carcinoma. PATIENTS AND METHODS: Patients initially received oral sorafenib 400 mg twice daily during the initial run-in period. After 12 weeks, patients with changes in bidimensional tumor measurements that were less than 25% from baseline were randomly assigned to sorafenib or placebo for an additional 12 weeks; patients with > or = 25% tumor shrinkage continued open-label sorafenib; patients with > or = 25% tumor growth discontinued treatment. The primary end point was the percentage of randomly assigned patients remaining progression free at 24 weeks after the initiation of sorafenib. RESULTS: Of 202 patients treated during the run-in period, 73 patients had tumor shrinkage of > or = 25%. Sixty-five patients with stable disease at 12 weeks were randomly assigned to sorafenib (n = 32) or placebo (n = 33). At 24 weeks, 50% of the sorafenib-treated patients were progression free versus 18% of the placebo-treated patients (P = .0077). Median progression-free survival (PFS) from randomization was significantly longer with sorafenib (24 weeks) than placebo (6 weeks; P = .0087). Median overall PFS was 29 weeks for the entire renal cell carcinoma population (n = 202). Sorafenib was readministered in 28 patients whose disease progressed on placebo; these patients continued on sorafenib until further progression, for a median of 24 weeks. Common adverse events were skin rash/desquamation, hand-foot skin reaction, and fatigue; 9% of patients discontinued therapy, and no patients died from toxicity. CONCLUSION: Sorafenib has significant disease-stabilizing activity in metastatic renal cell carcinoma and is tolerable with chronic daily therapy.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Benzenossulfonatos/administração & dosagem , Benzenossulfonatos/efeitos adversos , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Piridinas/administração & dosagem , Piridinas/efeitos adversos , Administração Oral , Adulto , Idoso , Carcinoma de Células Renais/patologia , Intervalo Livre de Doença , Esquema de Medicação , Feminino , Humanos , Neoplasias Renais/secundário , Masculino , Pessoa de Meia-Idade , Niacinamida/análogos & derivados , Compostos de Fenilureia , Sorafenibe , Análise de Sobrevida , Resultado do Tratamento
19.
J Clin Oncol ; 24(7): 1145-51, 2006 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16505434

RESUMO

PURPOSE: To study the safety of bevacizumab with capecitabine-based chemoradiotherapy. PATIENTS AND METHODS: Patients with inoperable pancreatic adenocarcinoma received bevacizumab 2 weeks before radiotherapy (50.4 Gy treating the primary tumor and gross adenopathy), every 2 weeks during radiotherapy (12 patients each at 2.5, 5.0, 7.5, and 10 mg/kg), and after radiotherapy until disease progression. Capecitabine was administered on days 14 through 52 (650 mg/m2 orally twice daily for the first six patients; 825 mg/m2 for the remaining patients). RESULTS: Significant acute gastrointestinal (43% grade 2; 4% grade 3), hand and foot syndrome (21% grade 2), and transient hematologic (8% grade 3 or greater) events were uncommon with protocol mandated dose reductions of capecitabine grade 2 toxicity (43% of patients). Among the first 30 patients treated, three patients had tumor-associated bleeding duodenal ulcers, and one had a contained duodenal perforation. No additional bleeding events occurred among the final 18 patients after patients with duodenal involvement by tumor were excluded. Nine (20%) of 46 assessable patients had confirmed partial responses until distant progression for a median of 6.2 months. Four patients have undergone pancreaticoduodenectomy without perioperative complication. The median survival was 11.6 months (95% CI, 9.6 to 13.6), from the start of protocol therapy. CONCLUSION: Concurrent bevacizumab did not significantly increase the acute toxicity of a relatively well-tolerated chemoradiotherapy regimen. However, ulceration and bleeding in the radiation field possibly related to bevacizumab occurred when tumor involved the duodenal mucosa. The encouraging efficacy end points suggest that the further study of bevacizumab with chemoradiotherapy is warranted.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Bevacizumab , Capecitabina , Quimioterapia Adjuvante , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/análogos & derivados , Sistema Digestório/efeitos dos fármacos , Esquema de Medicação , Feminino , Fluoruracila/análogos & derivados , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Pancreáticas/patologia , Pancreaticoduodenectomia , Úlcera Péptica Hemorrágica/induzido quimicamente , Radioterapia Adjuvante , Resultado do Tratamento
20.
Cancer Biol Ther ; 4(11): 1263-9, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16319525

RESUMO

Cyclooxygenase-2 (COX-2) is constitutively expressed in most human primary carcinomas and with its synthesized product, prostaglandin E2 (PGE2), appears to play important roles in tumor invasion, angiogenesis, resistance to apoptosis and suppression of host immunity. However, the molecular mechanisms that control COX-2 expression are unclear. The purpose of this study was to clarify the mechanism of basal and PGE2-mediated COX-2 expression in the highly metastatic L3.6pl human pancreatic cancer cell line. Using RNA interference to disrupt the expression of CREB and the NF-kappaB p65 subunit, we found that both are involved in maintaining basal COX-2 expression in L3.6pl cells. We also demonstrated that PGE2 increased the cyclic AMP concentration, thereby activating protein kinase A (PKA), which in turn phosphorylated the cyclic AMP response element binding protein (CREB), leading to interaction with the cyclic AMP response element in the promoter region of the COX-2 gene. Immunocytochemical analysis confirmed that PGE2 stimulated the translocation of PKA to the nucleus and increased the immuno-reactivity of phosphorylated CREB. Pretreatment with the PKA selective inhibitor H 89 and the E-prostanoid receptor 2 inhibitor AH 6809 reduced COX-2 upregulation by PGE2. Electrophoretic mobility shift assay and chromatin immunoprecipitation assay results further suggested a role for CREB in COX-2 transcriptional control. Understanding the pathways that control COX-2 expression may lead to a better understanding of its dysregulation in pancreatic carcinomas and facilitate the development of novel therapeutic approaches.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/patologia , Linhagem Celular Tumoral , AMP Cíclico/análise , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/análise , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Ciclo-Oxigenase 2/genética , Dinoprostona/farmacologia , Ativação Enzimática/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Isoquinolinas/farmacologia , Modelos Biológicos , Neoplasias Pancreáticas/genética , Fosforilação/efeitos dos fármacos , Antagonistas de Prostaglandina/farmacologia , Sulfonamidas/farmacologia , Xantonas/farmacologia
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