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1.
Urol Oncol ; 39(8): 493.e9-493.e15, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33353864

RESUMO

INTRODUCTION: Men diagnosed with localized prostate cancer must navigate a highly preference-sensitive decision between treatment options with varying adverse outcome profiles. We evaluated whether use of a decision support tool previously shown to decrease decisional conflict also impacted the secondary outcome of post-treatment decision regret. METHODS: Participants were randomized to receive personalized decision support via the Personal Patient Profile-Prostate or usual care prior to a final treatment decision. Symptoms were measured just before randomization and 6 months later; decision regret was measured at 6 months along with records review to ascertain treatment choices. Regression modeling explored associations between baseline variables including race and D`Amico risk, study group, and 6-month variables regret, choice, and symptoms. RESULTS: At 6 months, 287 of 392 (73%) men returned questionnaires of which 257 (89%) had made a treatment choice. Of that group, 201 of 257 (78%) completely answered the regret scale. Regret was not significantly different between participants randomized to the P3P intervention compared to the control group (P = 0.360). In univariate analyses, we found that Black men, men with hormonal symptoms, and men with bowel symptoms reported significantly higher decision regret (all P < 0.01). Significant interactions were detected between race and study group (intervention vs. usual care) in the multivariable model; use of the Personal Patient Profile-Prostate was associated with significantly decreased decisional regret among Black men (P = 0.037). Interactions between regret, symptoms and treatment revealed that (1) men choosing definitive treatment and reporting no hormonal symptoms reported lower regret compared to all others; and (2) men choosing active surveillance and reporting bowel symptoms had higher regret compared to all others. CONCLUSION: The Personal Patient Profile-Prostate decision support tool may be most beneficial in minimizing decisional regret for Black men considering treatment options for newly-diagnosed prostate cancer. TRIAL REGISTRATION: NCT01844999.


Assuntos
Comportamento de Escolha , Tomada de Decisões/fisiologia , Técnicas de Apoio para a Decisão , Emoções/fisiologia , Efeitos Adversos de Longa Duração/patologia , Neoplasias da Próstata/psicologia , Neoplasias da Próstata/terapia , Terapia Combinada , Atenção à Saúde , Seguimentos , Humanos , Efeitos Adversos de Longa Duração/etiologia , Masculino , Prognóstico , Inquéritos e Questionários
2.
J Urol ; 199(1): 89-97, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28754540

RESUMO

PURPOSE: We evaluated the efficacy of the web based P3P (Personal Patient Profile-Prostate) decision aid vs usual care with regard to decisional conflict in men with localized prostate cancer. MATERIALS AND METHODS: A randomized (1:1), controlled, parallel group, nonblinded trial was performed in 4 regions of the United States. Eligible men had clinically localized prostate cancer and an upcoming consultation, and they spoke and read English or Spanish. Participants answered questionnaires to report decision making stage, personal characteristics, concerns and preferences plus baseline symptoms and decisional conflict. A randomization algorithm allocated participants to receive tailored education and communication coaching, generic teaching sheets and external websites plus a 1-page summary to clinicians (intervention) or the links plus materials provided in clinic (usual care). Conflict outcomes and the number of consultations were measured at 1 month. Univariate and multivariable models were used to analyze outcomes. RESULTS: A total of 392 men were randomized, including 198 to intervention and 194 to usual care, of whom 152 and 153, respectively, returned 1-month outcomes. The mean ± SD 1-month decisional conflict scale (score range 0 to 100) was 10.9 ± 16.7 for intervention and 9.9 ± 18.0 for usual care. The multivariable model revealed significantly reduced conflict in the intervention group (-5.00, 95% CI -9.40--0.59). Other predictors of conflict included income, marital or partner status, decision status, number of consultations, clinical site and D'Amico risk classification. CONCLUSIONS: In this multicenter trial the decision aid significantly reduced decisional conflict. Other variables impacted conflict and modified the effect of the decision aid, notably risk classification, consultations and resources. P3P is an effective adjunct for shared decision making in men with localized prostate cancer.


Assuntos
Técnicas de Apoio para a Decisão , Internet , Neoplasias da Próstata/terapia , Adulto , Idoso , Algoritmos , Biópsia , Demografia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/patologia , Inquéritos e Questionários , Estados Unidos
4.
Cancer ; 121(15): 2603-11, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25903013

RESUMO

BACKGROUND: Patients with biochemical disease recurrence (BCR) after definitive treatment for prostate cancer comprise a heterogeneous population for whom standard therapy options are lacking. The purpose of the current trial was to evaluate the feasibility, toxicity, and efficacy of early multimodality systemic therapy in men with BCR. METHODS: Eligible patients had an increasing prostate-specific antigen (PSA) level, a PSA doubling time ≤10 months, and no evidence of metastases after radical prostatectomy (RP) and/or radiotherapy (RT) for localized disease. Treatment consisted of docetaxel at a dose of 75 mg/m(2) every 3 weeks for 4 cycles, bevacizumab at a dose of 15 mg/kg every 3 weeks for 8 cycles, and androgen deprivation therapy (ADT) for 18 months. The primary endpoint was the percentage of patients who were free from PSA progression 1 year after the completion of therapy. RESULTS: A total of 41 patients were included in the analysis. At 1 year after the completion of ADT, 45% of patients (13 of 29 patients) and 29% of patients (5 of 17 patients) with a testosterone level ≥100 ng/dL and ≥240 ng/dL, respectively, had a PSA <0.2 ng/mL. The median follow-up was 27.5 months (interquartile range, 21.8-38.1 months). Eight patients (20%) were free from PSA progression, 19 patients (46%) did not reinitiate ADT, and 34 patients (83%) were free from metastasis. Sixteen patients (39%) experienced grade 3 and 5 patients (12%) experienced grade 4 toxicities (toxicity was assessed using the National Cancer Institute Common Terminology Criteria for Adverse Events [version 3.0]). CONCLUSIONS: Multimodality systemic therapy with docetaxel, bevacizumab, and ADT is feasible and produces PSA responses in men with BCR. Long-term follow-up is needed to determine the percentage of patients with a durable PSA response who are able to avoid having to reinitiate prostate cancer therapy.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antagonistas de Androgênios/administração & dosagem , Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Taxoides/administração & dosagem , Adenocarcinoma/sangue , Adenocarcinoma/patologia , Antagonistas de Androgênios/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Antineoplásicos Hormonais/administração & dosagem , Antineoplásicos Hormonais/efeitos adversos , Bevacizumab , Biomarcadores Tumorais/sangue , Quimioterapia Adjuvante , Docetaxel , Humanos , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Taxoides/efeitos adversos , Resultado do Tratamento
5.
JAMA ; 311(11): 1143-9, 2014 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-24643604

RESUMO

IMPORTANCE: Prostate cancer screening with the prostate-specific antigen (PSA) test remains controversial. OBJECTIVE: To review evidence from randomized trials and related modeling studies examining the effect of PSA screening vs no screening on prostate cancer-specific mortality and to suggest an approach balancing potential benefits and harms. EVIDENCE ACQUISITION: MEDLINE, EMBASE, and the Cochrane Register of Controlled Trials were searched from January 1, 2010, to April 3, 2013, for PSA screening trials to update a previous systematic review. Another search was performed in EMBASE and MEDLINE to identify modeling studies extending the results of the 2 large randomized trials identified. The American Heart Association Evidence-Based Scoring System was used to rate level of evidence. RESULTS: Two trials-the Prostate, Lung, Colorectal and Ovarian (PLCO) screening trial and the European Randomized Study of Screening for Prostate Cancer (ERSPC)-dominate the evidence regarding PSA screening. The former trial demonstrated an increase in cancer incidence in the screening group (relative risk [RR], 1.12; 95% CI, 1.07-1.17) but no cancer-specific mortality benefit to PSA screening after 13-year follow-up (RR, 1.09; 95% CI, 0.87-1.36). The ERSPC demonstrated an increase in cancer incidence with screening (RR, 1.63; 95% CI, 1.57-1.69) and an improvement in the risk of prostate cancer-specific death after 11 years (RR, 0.79; 95% CI, 0.68-0.91). The ERSPC documented that 37 additional men needed to receive a diagnosis through screening for every 1 fewer prostate cancer death after 11 years of follow-up among men aged 55 to 69 years (level B evidence for prostate cancer mortality reduction). Harms associated with screening include false-positive results and complications of biopsy and treatment. Modeling studies suggest that this high ratio of additional men receiving diagnoses to prostate cancer deaths prevented will decrease during a longer follow-up (level B evidence). CONCLUSIONS AND RELEVANCE: Available evidence favors clinician discussion of the pros and cons of PSA screening with average-risk men aged 55 to 69 years. Only men who express a definite preference for screening should have PSA testing. Other strategies to mitigate the potential harms of screening include considering biennial screening, a higher PSA threshold for biopsy, and conservative therapy for men receiving a new diagnosis of prostate cancer.


Assuntos
Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Detecção Precoce de Câncer , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Modelos Teóricos , Neoplasias da Próstata/sangue , Neoplasias da Próstata/mortalidade , Ensaios Clínicos Controlados Aleatórios como Assunto , Valores de Referência
8.
Ann Intern Med ; 158(12): 853-60, 2013 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-23778902

RESUMO

BACKGROUND: Observation is underutilized among men with localized, low-risk prostate cancer. OBJECTIVE: To assess the costs and benefits of observation versus initial treatment. DESIGN: Decision analysis simulating treatment or observation. DATA SOURCES: Medicare schedules, published literature. TARGET POPULATION: Men aged 65 and 75 years who had newly diagnosed low-risk prostate cancer (prostate-specific antigen level <10 µg/L, stage ≤T2a, Gleason score ≤3 + 3). TIME HORIZON: Lifetime. PERSPECTIVE: Societal. INTERVENTION: Treatment (brachytherapy, intensity-modulated radiation therapy, or radical prostatectomy) or observation (active surveillance [AS] or watchful waiting [WW]). OUTCOME MEASURES: Quality-adjusted life expectancy and costs. RESULTS OF BASE-CASE ANALYSIS: Observation was more effective and less costly than initial treatment. Compared with AS, WW provided 2 additional months of quality-adjusted life expectancy (9.02 vs. 8.85 years) at a savings of $15,374 ($24,520 vs. $39,894) in men aged 65 years and 2 additional months (6.14 vs. 5.98 years) at a savings of $11,746 ($18,302 vs. $30,048) in men aged 75 years. Brachytherapy was the most effective and least expensive initial treatment. RESULTS OF SENSITIVITY ANALYSIS: Treatment became more effective than observation when it led to more dramatic reductions in prostate cancer death (hazard ratio, 0.47 vs. WW and 0.64 vs. AS). Active surveillance became as effective as WW in men aged 65 years when the probability of progressing to treatment on AS decreased below 63% or when the quality of life with AS versus WW was 4% higher in men aged 65 years or 1% higher in men aged 75 years. Watchful waiting remained least expensive in all analyses. LIMITATION: Results depend on outcomes reported in the published literature, which is limited. CONCLUSION: Among these men, observation is more effective and costs less than initial treatment, and WW is most effective and least expensive under a wide range of clinical scenarios. PRIMARY FUNDING SOURCE: National Cancer Institute, U.S. Department of Defense, Prostate Cancer Foundation, and Institute for Clinical and Economic Review.


Assuntos
Custos de Cuidados de Saúde , Neoplasias da Próstata/economia , Neoplasias da Próstata/terapia , Conduta Expectante/economia , Idoso , Biópsia/economia , Braquiterapia/economia , Análise Custo-Benefício , Técnicas de Apoio para a Decisão , Exame Retal Digital/economia , Progressão da Doença , Humanos , Masculino , Gradação de Tumores , Estadiamento de Neoplasias , Antígeno Prostático Específico/sangue , Prostatectomia/economia , Neoplasias da Próstata/mortalidade , Anos de Vida Ajustados por Qualidade de Vida , Fatores de Risco , Sensibilidade e Especificidade
9.
BJU Int ; 110(11): 1729-35, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22928480

RESUMO

UNLABELLED: Study Type--Therapy (cohort) Level of Evidence 2a. What's known on the subject? and What does the study add? Despite expanding treatment options for castration-resistant prostate cancer (CRPC), therapies with long response duration remain intangible due to prostate cancer cells' natural ability to develop iterative resistance. Androgen receptor (AR) signaling has been shown to play a critical role in CRPC and its expression is regulated by the PI3K-Akt pathway. Thus inhibition of AR signalling and PI3K-Akt-mTOR (a downstream mediator of the PI3K-Akt pathway) pathway is a logical combination in CRPC and we report a phase II trial of RAD001 and bicalutamide. Our study is the first clinical trial report of an AR inhibitor of PI3K-Akt-mTOR. The AR pathway and the PI3K-Akt-mTOR pathway are two of the most relevant growth pathway for CRPC. Despite low efficacy results from our trial there will be significant interest in the field for these data (dose, schedule, response, toxicity, trial design) as newer generations of both AR inhibitors and PI3K-Akt-mTOR inhibitors are in development and likely will be tested in combination in CRPC. OBJECTIVES: • To determine best overall response and duration of response of RAD001, a selective inhibitor of mammalian target of rapamycin, in combination with bicalutamide in castration-resistant prostate cancer (CRPC). • To characterize the toxicity profile of RAD001 in combination with bicalutamide in patients with CRPC. PATIENTS AND METHODS: • A phase II study was conducted to explore the efficacy and tolerability of RAD001 (10 mg daily) in combination with bicalutamide (50 mg daily) in men with progressive CRPC. • The primary endpoint was a composite of prostate-specific antigen (PSA) level and measurable disease response by standard criteria. • This single-stage trial with a sample size of 38 eligible patients provided 90% power to differentiate a response rate of ≥ 40% from a response rate of ≤ 20%, as expected for bicalutamide alone (α= 0.10, power = 0.90). RESULTS: • In total, 36 men were enrolled, with a median (range) age of 68 (60-72) years and median (range) baseline PSA level of 22.2 (8.4-121.3) ng/mL, and 89% had metastatic disease. • There were 31 (86%) patients had previously used bicalutamide for a median duration of 7.4 months. • There were two patients with a confirmed PSA level decline ≥ 50%. • The median (interquartile range) time to progression was 8.7 (7.9-15.9) weeks. • The most common toxicity was grade 1/2 mucositis, which was observed in 20 (56%) patients. CONCLUSION: • The combination of RAD001 and bicalutamide in men with CRPC was well tolerated but had low activity and failed to achieve the primary endpoint of improved response compared to the results previously achieved for bicalutamide alone in this population.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Adenocarcinoma/sangue , Idoso , Antagonistas de Receptores de Andrógenos/uso terapêutico , Anilidas/administração & dosagem , Anilidas/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Resistencia a Medicamentos Antineoplásicos , Everolimo , Humanos , Masculino , Pessoa de Meia-Idade , Nitrilas/administração & dosagem , Nitrilas/efeitos adversos , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/sangue , Sirolimo/administração & dosagem , Sirolimo/efeitos adversos , Sirolimo/análogos & derivados , Compostos de Tosil/administração & dosagem , Compostos de Tosil/efeitos adversos , Resultado do Tratamento
11.
JAMA ; 304(21): 2373-80, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21119084

RESUMO

CONTEXT: In the United States, 192,000 men were diagnosed as having prostate cancer in 2009, the majority with low-risk, clinically localized disease. Treatment of these cancers is associated with substantial morbidity. Active surveillance is an alternative to initial treatment, but long-term outcomes and effect on quality of life have not been well characterized. OBJECTIVE: To examine the quality-of-life benefits and risks of active surveillance compared with initial treatment for men with low-risk, clinically localized prostate cancer. DESIGN AND SETTING: Decision analysis using a simulation model was performed: men were treated at diagnosis with brachytherapy, intensity-modulated radiation therapy (IMRT), or radical prostatectomy or followed up by active surveillance (a strategy of close monitoring of newly diagnosed patients with serial prostate-specific antigen measurements, digital rectal examinations, and biopsies, with treatment at disease progression or patient choice). Probabilities and utilities were derived from previous studies and literature review. In the base case, the relative risk of prostate cancer-specific death for initial treatment vs active surveillance was assumed to be 0.83. Men incurred short- and long-term adverse effects of treatment. PATIENTS: Hypothetical cohorts of 65-year-old men newly diagnosed as having clinically localized, low-risk prostate cancer (prostate-specific antigen level <10 ng/mL, stage ≤T2a disease, and Gleason score ≤6). MAIN OUTCOME MEASURE: Quality-adjusted life expectancy (QALE). RESULTS: Active surveillance was associated with the greatest QALE (11.07 quality-adjusted life-years [QALYs]), followed by brachytherapy (10.57 QALYs), IMRT (10.51 QALYs), and radical prostatectomy (10.23 QALYs). Active surveillance remained associated with the highest QALE even if the relative risk of prostate cancer-specific death for initial treatment vs active surveillance was as low as 0.6. However, the QALE gains and the optimal strategy were highly dependent on individual preferences for living under active surveillance and for having been treated. CONCLUSIONS: Under a wide range of assumptions, for a 65-year-old man, active surveillance is a reasonable approach to low-risk prostate cancer based on QALE compared with initial treatment. However, individual preferences play a central role in the decision whether to treat or to pursue active surveillance.


Assuntos
Técnicas de Apoio para a Decisão , Neoplasias da Próstata/terapia , Conduta Expectante , Idoso , Braquiterapia , Estudos de Coortes , Progressão da Doença , Humanos , Masculino , Planejamento de Assistência ao Paciente , Prognóstico , Antígeno Prostático Específico/sangue , Prostatectomia , Neoplasias da Próstata/sangue , Anos de Vida Ajustados por Qualidade de Vida , Risco
12.
BJU Int ; 106(7): 979-85, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20230380

RESUMO

OBJECTIVE: To examine the effect of short-course androgen-suppression therapy (AST) before brachytherapy on all-cause mortality (ACM) rates, stratified by the presence or absence of a history of myocardial infarction (MI) or stroke. AST is used to reduce prostate size to enable men with favourable-risk prostate cancer to undergo brachytherapy, but no disease-specific benefit has been reported for this practice, and AST use has been associated with an increased risk of ACM in some men with pre-existing cardiovascular disease. PATIENTS AND METHODS: The study comprised 12792 men with favourable-risk disease, i.e. a prostate-specific antigen (PSA) level of <20 ng/mL, Gleason score ≤7 and clinical category ≤T2c, treated between 1991 and 2007 at community-based medical centres with brachytherapy ± neoadjuvant AST. Multivariable Cox regression analysis was used to assess whether there were significant associations between AST use in men with a history of MI or stroke and the risk of ACM, adjusting for age, treatment year, and known prognostic factors of prostate cancer. RESULTS: After a median (interquartile range) follow-up of 3.8 (2.0-5.9) years there were 1557 deaths. The risk of ACM was lower in men with no history of MI or stroke than in those with this history, whether AST was used (adjusted hazard ratio 0.79, 95% confidence interval 0.67-0.92; P= 0.003) or not (0.74, 0.65-0.85; P < 0.001). However, men with a history of MI or stroke treated with AST had a greater risk of ACM than those not treated with AST (1.2, 1.05-1.38; P= 0.008). CONCLUSION: The use of short-course AST in men with a history of MI or stroke is associated with a greater risk of ACM in men with favourable-risk prostate cancer.


Assuntos
Antagonistas de Androgênios/efeitos adversos , Infarto do Miocárdio/induzido quimicamente , Neoplasias da Próstata/terapia , Acidente Vascular Cerebral/induzido quimicamente , Idoso , Idoso de 80 Anos ou mais , Androgênios/metabolismo , Braquiterapia , Causas de Morte , Terapia Combinada , Métodos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Neoplasias da Próstata/complicações , Neoplasias da Próstata/mortalidade , Acidente Vascular Cerebral/mortalidade , Resultado do Tratamento
13.
Cancer ; 116(8): 1887-92, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20162710

RESUMO

BACKGROUND: This report evaluated whether biochemical recurrence (BCR) as a time-dependent covariate (t) after radical prostatectomy (RP) for prostate cancer was associated with the risk of death and whether salvage therapy with radiotherapy (RT) and/or hormonal therapy (HT) can lessen this risk METHODS: This was a retrospective cohort study of 3071 men who underwent RP at Duke University between 1988 and 2008 and had complete follow-up data. A Cox regression multivariable analysis was used to determine whether BCR (t) was associated with the risk of death in men after adjusting for age, prostatectomy findings, and the use of salvage RT and/or HT. RESULTS: After a median follow-up of 7.4 years, 546 (17.8%) men experienced BCR and 454 (14.8%) died. The median follow-up after prostate-specific antigen (PSA) failure was 11.2 years (interquartile range, 5.8-16.0 years). BCR (t) was associated with an increased risk of death (adjusted hazards ratio [AHR], 1.03; 95% confidence interval [95% CI], 1.004-1.06 [P = .025]). In men who experienced BCR, a PSA doubling time <6 months was associated with an increased risk of death (AHR, 1.55; 95% CI, 1.15-2.1 [P = .004]); whereas a decrease in the risk of death was observed in men who received RT (AHR, 0.58; 95% CI, 0.40-0.58 [P = .002]) or HT (AHR, 0.56; 95% CI, 0.37-0.84 [P = .005]) after BCR. CONCLUSIONS: The occurrence of BCR was found to increase the risk of death in men undergoing RP for prostate cancer, and this risk appeared to increase as the time to BCR shortened. However, the addition of RT and/or HT in men with BCR significantly lowered this risk.


Assuntos
Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/mortalidade , Idoso , Antagonistas de Androgênios/uso terapêutico , Antineoplásicos Hormonais/uso terapêutico , Terapia Combinada , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Prostatectomia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/terapia , Radioterapia Adjuvante , Recidiva , Risco , Terapia de Salvação , Fatores de Tempo , Falha de Tratamento
15.
Clin Cancer Res ; 10(19): 6710-21, 2004 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-15475462

RESUMO

Hepatoma is one of the most frequently occurring cancers worldwide. However, effective chemotherapeutic agents for this disease have not been developed. Acyclic retinoid, a novel synthetic retinoid, can reduce the incidence of postsurgical recurrence of hepatoma and improve the survival rate. OSI-461, a potent derivative of exisulind, can increase intracellular levels of cyclic GMP, which leads to activation of protein kinase G and induction of apoptosis in cancer cells. In the present study, we examined the combined effects of acyclic retinoid plus OSI-461 in the HepG2 human hepatoma cell line. We found that the combination of as little as 1.0 micromol/L acyclic retinoid and 0.01 micromol/L OSI-461 exerted synergistic inhibition of the growth of HepG2 cells. Combined treatment with low concentrations of these two agents also acted synergistically to induce apoptosis in HepG2 cells through induction of Bax and Apaf-1, reduction of Bcl-2 and Bcl-xL, and activation of caspase-3, -8, and -9. OSI-461 enhanced the G0-G1 arrest caused by acyclic retinoid, and the combination of these agents caused a synergistic decrease in the levels of expression of cyclin D1 protein and mRNA, inhibited cyclin D1 promoter activity, decreased the level of hyperphosphorylated forms of the Rb protein, induced increased cellular levels of the p21(CIP1) protein and mRNA, and stimulated p21(CIP1) promoter activity. Moreover, OSI-461 enhanced the ability of acyclic retinoid to induce increased cellular levels of retinoic acid receptor beta and to stimulate retinoic acid response element-chloramphenicol acetyltransferase activity. A hypothetical model involving concerted effects on p21(CIP1) and retinoic acid receptor beta expression is proposed to explain these synergistic effects. Our results suggest that the combination of acyclic retinoid plus OSI-461 might be an effective regimen for the chemoprevention and chemotherapy of human hepatoma and possibly other malignancies.


Assuntos
Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Sulindaco/análogos & derivados , Tretinoína/análogos & derivados , Tretinoína/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Western Blotting , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Moléculas de Adesão Celular/metabolismo , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Cloranfenicol O-Acetiltransferase/genética , Cloranfenicol O-Acetiltransferase/metabolismo , GMP Cíclico/metabolismo , Ciclina D1/genética , Ciclina D1/metabolismo , Inibidor de Quinase Dependente de Ciclina p21 , Proteínas do Citoesqueleto/metabolismo , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Fase G1/efeitos dos fármacos , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Proteínas dos Microfilamentos , Modelos Biológicos , Fosfoproteínas/metabolismo , Fosforilação/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores do Ácido Retinoico/genética , Receptores do Ácido Retinoico/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Elementos de Resposta/genética , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Proteína do Retinoblastoma/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sulindaco/farmacologia , Transativadores/metabolismo , Transfecção , Proteína Supressora de Tumor p53/metabolismo , beta Catenina
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