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1.
Future Oncol ; 12(23): 2689-2699, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27528114

RESUMO

AIM: This study seeks to improve the understanding of treatment patterns and associated health-related quality of life (HRQoL), clinical outcomes and healthcare utilization in US patients with castration-resistant prostate cancer (CRPC). PATIENTS & METHODS: Treatment Registry for Outcomes in CRPC Patients (TRUMPET) is a US-based, prospective, observational multicenter registry (NCT02380274) involving patients with CRPC and their caregivers. Patients initiating their first active treatment course will be enrolled from urology and medical oncology practices, with data captured up to 4 years. RESULTS: Information on prescribing patterns, HRQoL, clinical outcomes and healthcare utilization will be collected. CONCLUSION: TRUMPET will enable scientific understanding of disease management in terms of HRQoL, clinical outcomes and healthcare utilization in clinical practice for patients with CRPC.


Assuntos
Neoplasias de Próstata Resistentes à Castração/epidemiologia , Cuidadores , Gerenciamento Clínico , Custos de Cuidados de Saúde , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Aceitação pelo Paciente de Cuidados de Saúde , Satisfação do Paciente , Neoplasias de Próstata Resistentes à Castração/diagnóstico , Neoplasias de Próstata Resistentes à Castração/terapia , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida , Sistema de Registros , Pesquisa , Resultado do Tratamento , Estados Unidos/epidemiologia
3.
Eur Urol Open Sci ; 34: 70-78, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34934969

RESUMO

BACKGROUND: Phase 2 trial endpoints that can be utilized in high-risk biochemical recurrence (BCR) after prostatectomy as a way of more rapidly identifying treatments for phase 3 trials are urgently needed. The efficacy of abiraterone acetate plus prednisone (AAP) in BCR is unknown. OBJECTIVE: To compare the rates of complete biochemical responses after testosterone recovery after 8 mo of AAP and degarelix, a gonadotropin-releasing hormone antagonist, alone or in combination. DESIGN SETTING AND PARTICIPANTS: Patients with BCR (prostate-specific antigen [PSA] ≥1.0 ng/ml, PSA doubling time ≤9 mo, no metastases on standard imaging, and testosterone ≥150 ng/dl) after prostatectomy (with or without prior radiotherapy) were included in this study. INTERVENTION: Patients were randomized to AAP (arm 1), AAP with degarelix (arm 2), or degarelix (arm 3) for 8 mo, and monitored for 18 mo. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was undetectable PSA with testosterone >150 ng/dl at 18 mo. Secondary endpoints were undetectable PSA at 8 mo and time to testosterone recovery. RESULTS AND LIMITATIONS: For the 122 patients enrolled, no difference was found between treatments for the primary endpoint (arm 1: 5.1% [95% confidence interval {CI}: 1-17%], arm 2: 17.1% [95% CI: 7-32%], arm 3: 11.9% [95% CI: 4-26%]; arm 1 vs 2, p = 0.93; arm 2 vs 3, p = 0.36). AAP therapy showed the shortest median time to testosterone recovery (36.0 wk [95% CI: 35.9-36.1]) relative to degarelix (52.9 wk [95% CI: 49.0-56.0], p < 0.001). Rates of undetectable PSA at 8 mo differed between AAP with degarelix and degarelix alone (p = 0.04), but not between AAP alone and degarelix alone (p = 0.12). Limitations of this study include a lack of long-term follow-up. CONCLUSIONS: Rates of undetectable PSA levels with testosterone recovery were similar between arms, suggesting that increased androgen suppression with AAP and androgen deprivation therapy (ADT) is unlikely to eradicate recurrent disease compared with ADT alone. PATIENT SUMMARY: We evaluated the use of abiraterone acetate plus prednisone (AAP) and androgen deprivation therapy (ADT), AAP alone, or ADT alone in men with biochemically recurrent, nonmetastatic prostate cancer. While more men who received the combination had an undetectable prostate-specific antigen (PSA) level at 8 mo on treatment, once men came off treatment and testosterone level rose, there was no difference in the rates of undetectable PSA levels. This suggests that the combination is not able to eradicate disease any better than ADT alone.

4.
Value Health ; 13(5): 613-23, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20230544

RESUMO

OBJECTIVE: A conceptual framework for patient-reported outcomes (PROs) is a structured representation of outcome concepts and issues. Our aim was to develop a conceptual framework of PROs for hormone-refractory prostate cancer (HRPC) to support measurement clarity. METHODS: Relevant outcome issues were identified from review of recent clinical trials. This provided content for an interview with 15 metastatic HRPC patients and a survey of 10 practitioners. All participants were asked about the relevance and importance of 26 outcomes and were allowed to nominate new outcomes. Practitioners were also asked to determine which outcomes endorsed by patients were attributable to the disease (symptoms) versus treatment (side effects). Analyses of archived clinical trial data were used to verify and augment the interview and survey results. RESULTS: Patients endorsed 11 concerns as relevant and important to HRPC including general pain, bone pain, urinary problems, fatigue, appetite loss, constipation, erectile dysfunction, peripheral neuropathy, diarrhea, PSA anxiety, and changes in self image. Practitioner judgments helped classify each concern into one of four categories, disease symptom, treatment side effect, both symptom and side effect, or psychological concern. Additionally, patients endorsed (and practitioners confirmed) the relevance and importance of several general domains of quality of life. Analyses of archived data confirmed the importance of these issues and suggested two additional concerns. CONCLUSION: Findings were used to propose a conceptual framework of PROs for metastatic HRPC. Such frameworks can be used to help specify targets for assessment in clinical studies such as treatment trials.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Mitoxantrona/uso terapêutico , Prednisona/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Ansiedade , Área Sob a Curva , Intervalos de Confiança , Coleta de Dados , Indicadores Básicos de Saúde , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Avaliação de Resultados em Cuidados de Saúde/métodos , Medição da Dor , Antígeno Prostático Específico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/psicologia , Psicometria , Qualidade de Vida/psicologia , Autoimagem
5.
Eur J Cancer ; 114: 107-116, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31082669

RESUMO

PURPOSE: Radium 223 dichloride (radium-223) is an alpha particle-emitting bone-directed therapy that prolongs overall survival in men with bone-predominant metastatic castration-resistant prostate cancer (mCRPC). Docetaxel is an antimicrotubule cytotoxic agent that improves survival in mCRPC. We investigated whether combining these potentially cross-sensitising agents to dually target tumour and bone would be safe and effective. PATIENTS AND METHODS: Phase 1 was a dose escalation study to define a recommended phase 2 dose (RP2D) of docetaxel and radium-223. In phase 2a, patients were randomised 2:1 to the recommended combination regimen or docetaxel at a dose of 75 mg/m2 every 3 weeks (q3w). Patients with bone-predominant mCRPC were eligible. End-points were safety, efficacy and treatment-related changes in serum and imaging biomarkers. RESULTS: Twenty patients were enrolled in phase 1; 53 patients were randomised in phase 2a: 36 to combination treatment and 17 to docetaxel alone. The RP2D for the combination was radium-223 55 kBq/kg every six weeks × 5 doses, plus docetaxel 60 mg/m2 q3w × 10 doses. Febrile neutropenia was dose limiting. A higher rate of febrile neutropenia was seen in the docetaxel monotherapy arm (15% vs 0%); the safety profile of the treatment groups was otherwise similar. The combination arm had more durable suppression of prostate-specific antigen (median time to progression, 6.6 vs 4.8 months, respectively), alkaline phosphatase (9 vs 7 months) and osteoblastic bone deposition markers. CONCLUSIONS: Radium-223 in combination with docetaxel at the RP2D was well tolerated. Exploratory efficacy data suggested enhanced antitumour activity for the combination relative to docetaxel alone. Comparative studies with end-points of clinical benefit are warranted. ClinicalTrials.gov number: NCT01106352.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/secundário , Docetaxel/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Rádio (Elemento)/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Docetaxel/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias de Próstata Resistentes à Castração/complicações , Rádio (Elemento)/farmacologia
6.
J Clin Oncol ; 36(11): 1080-1087, 2018 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-29384722

RESUMO

Purpose Docetaxel added to androgen-deprivation therapy (ADT) significantly increases the longevity of some patients with metastatic hormone-sensitive prostate cancer. Herein, we present the outcomes of the CHAARTED (Chemohormonal Therapy Versus Androgen Ablation Randomized Trial for Extensive Disease in Prostate Cancer) trial with more mature follow-up and focus on tumor volume. Patients and Methods In this phase III study, 790 patients with metastatic hormone-sensitive prostate cancer were equally randomly assigned to receive either ADT in combination with docetaxel 75 mg/m2 for up to six cycles or ADT alone. The primary end point of the study was overall survival (OS). Additional analyses of the prospectively defined low- and high-volume disease subgroups were performed. High-volume disease was defined as presence of visceral metastases and/or ≥ four bone metastases with at least one outside of the vertebral column and pelvis. Results At a median follow-up of 53.7 months, the median OS was 57.6 months for the chemohormonal therapy arm versus 47.2 months for ADT alone (hazard ratio [HR], 0.72; 95% CI, 0.59 to 0.89; P = .0018). For patients with high-volume disease (n = 513), the median OS was 51.2 months with chemohormonal therapy versus 34.4 months with ADT alone (HR, 0.63; 95% CI, 0.50 to 0.79; P < .001). For those with low-volume disease (n = 277), no OS benefit was observed (HR, 1.04; 95% CI, 0.70 to 1.55; P = .86). Conclusion The clinical benefit from chemohormonal therapy in prolonging OS was confirmed for patients with high-volume disease; however, for patients with low-volume disease, no OS benefit was discerned.


Assuntos
Antagonistas de Androgênios/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Docetaxel/administração & dosagem , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Antagonistas de Androgênios/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Docetaxel/efeitos adversos , Humanos , Masculino , Metástase Neoplásica , Neoplasias Hormônio-Dependentes/mortalidade , Neoplasias Hormônio-Dependentes/patologia , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Fatores de Tempo , Resultado do Tratamento
7.
J Clin Oncol ; 36(10): 991-999, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29261439

RESUMO

Purpose To determine whether cotargeting poly (ADP-ribose) polymerase-1 plus androgen receptor is superior to androgen receptor inhibition in metastatic castration-resistant prostate cancer (mCRPC) and whether ETS fusions predict response. Patients and Methods Patients underwent metastatic site biopsy and were stratified by ETS status and randomly assigned to abiraterone plus prednisone without (arm A) or with veliparib (arm B). Primary objectives were: confirmed prostate-specific antigen (PSA) response rate (RR) and whether ETS fusions predicted response. Secondary objectives were: safety, measurable disease RR (mRR), progression-free survival (PFS), and molecular biomarker analysis. A total of 148 patients were randomly assigned to detect a 20% PSA RR improvement. Results A total of 148 patients with mCRPC were randomly assigned: arm A, n = 72; arm B, n = 76. There were no differences in PSA RR (63.9% v 72.4%; P = .27), mRR (45.0% v 52.2%; P = .51), or median PFS (10.1 v 11 months; P = .99). ETS fusions did not predict response. Exploratory analysis of tumor sequencing (80 patients) revealed: 41 patients (51%) were ETS positive, 20 (25%) had DNA-damage repair defect (DRD), 41 (51%) had AR amplification or copy gain, 34 (43%) had PTEN mutation, 33 (41%) had TP53 mutation, 39 (49%) had PIK3CA pathway activation, and 12 (15%) had WNT pathway alteration. Patients with DRD had significantly higher PSA RR (90% v 56.7%; P = .007) and mRR (87.5% v 38.6%; P = .001), PSA decline ≥ 90% (75% v 25%; P = .001), and longer median PFS (14.5 v 8.1 months; P = .025) versus those with wild-type tumors. Median PFS was longer in patients with normal PTEN (13.5 v 6.7 months; P = .02), TP53 (13.5 v 7.7 months; P = .01), and PIK3CA (13.8 v 8.3 months; P = .03) versus those with mutation or activation. In multivariable analysis adjusting for clinical covariates, DRD association with PFS remained significant. Conclusion Veliparib and ETS status did not affect response. Exploratory analysis identified a novel DRD association with mCRPC outcomes.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Reparo do DNA , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Idoso , Idoso de 80 Anos ou mais , Androstenos/administração & dosagem , Benzimidazóis/administração & dosagem , Biomarcadores Tumorais , Humanos , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Metástase Neoplásica , Inibidores de Poli(ADP-Ribose) Polimerases/administração & dosagem , Prednisona/administração & dosagem , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Proteínas Proto-Oncogênicas c-ets/genética , Receptores Androgênicos/metabolismo
8.
Eur Urol ; 71(5): 740-747, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27989354

RESUMO

BACKGROUND: Germline mutations in BRCA1/2 and ATM have been associated with prostate cancer (PCa) risk. OBJECTIVE: To directly assess whether germline mutations in these three genes distinguish lethal from indolent PCa and whether they confer any effect on age at death. DESIGN, SETTING, AND PARTICIPANTS: A retrospective case-case study of 313 patients who died of PCa and 486 patients with low-risk localized PCa of European, African, and Chinese descent. Germline DNA of each of the 799 patients was sequenced for these three genes. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Mutation carrier rates and their effect on lethal PCa were analyzed using the Fisher's exact test and Cox regression analysis, respectively. RESULTS AND LIMITATIONS: The combined BRCA1/2 and ATM mutation carrier rate was significantly higher in lethal PCa patients (6.07%) than localized PCa patients (1.44%), p=0.0007. The rate also differed significantly among lethal PCa patients as a function of age at death (10.00%, 9.08%, 8.33%, 4.94%, and 2.97% in patients who died ≤ 60 yr, 61-65 yr, 66-70 yr, 71-75 yr, and over 75 yr, respectively, p=0.046) and time to death after diagnosis (12.26%, 4.76%, and 0.98% in patients who died ≤ 5 yr, 6-10 yr, and>10 yr after a PCa diagnosis, respectively, p=0.0006). Survival analysis in the entire cohort revealed mutation carriers remained an independent predictor of lethal PCa after adjusting for race and age, prostate-specific antigen, and Gleason score at the time of diagnosis (hazard ratio=2.13, 95% confidence interval: 1.24-3.66, p=0.004). A limitation of this study is that other DNA repair genes were not analyzed. CONCLUSIONS: Mutation status of BRCA1/2 and ATM distinguishes risk for lethal and indolent PCa and is associated with earlier age at death and shorter survival time. PATIENT SUMMARY: Prostate cancer patients with inherited mutations in BRCA1/2 and ATM are more likely to die of prostate cancer and do so at an earlier age.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteína BRCA1/genética , Proteína BRCA2/genética , Mutação em Linhagem Germinativa , Neoplasias da Próstata/genética , Fatores Etários , Idoso , Povo Asiático/genética , População Negra/genética , Estudos de Casos e Controles , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Prognóstico , Modelos de Riscos Proporcionais , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Estudos Retrospectivos , Análise de Sequência de DNA , Análise de Sobrevida , População Branca/genética
9.
Asian J Androl ; 18(4): 586-91, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27030083

RESUMO

In spite of the development of new treatments for late stage prostate cancer, significant challenges persist to match individuals with effective targeted therapies. Genomic classification using high-throughput sequencing technologies has the potential to achieve this goal and make precision medicine a reality in the management of men with castrate-resistant prostate cancer. This chapter reviews some of the most recent studies that have resulted in significant progress in determining the landscape of somatic genomic alterations in this cohort and, more importantly, have provided clinically actionable information that could guide treatment decisions. This chapter reviews the current understanding of common alterations such as alterations of the androgen receptor and PTEN pathway, as well as ETS gene fusions and the growing importance of PARP inhibition. It also reviews recent studies that characterize the evolution to neuroendocrine tumors, which is becoming an increasingly important clinical problem. Finally, this chapter reviews recent innovative studies that characterize the compelling evolutionary history of lethal prostate cancer evidenced by polyclonal seeding and interclonal cooperation between metastasis and the importance of tumor clone dynamics measured serially in response to treatment. The genomic landscape of late stage prostate cancer is becoming better defined, and the prospect for assigning clinically actionable data to inform rationale treatment for individuals with this disease is becoming a reality.


Assuntos
PTEN Fosfo-Hidrolase/genética , Neoplasias da Próstata/genética , Receptores Androgênicos/genética , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , Genômica , Humanos , Masculino , Farmacogenética , Próstata/patologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia
10.
Thromb Haemost ; 89(1): 185-9, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12540969

RESUMO

Thrombin generation is increased in men with advanced prostate cancer. Thrombin has the ability to interact with, and affect the biology of, a variety of cell types including prostate cancer cell lines. We therefore looked for correlations between thrombin generation and other markers of disease activity in spot urine samples obtained from men with advanced prostate cancer. Excretion of part of the prothrombin activation peptide F(1+2) (called here iF2), interleukin-6 (IL-6), the bone turnover marker deoxypyridinoline (DpD), and vascular endothelial growth factor (VEGF) were quantitated in spot urine samples collected from 37 men with hormone-refractory prostate cancer. Following log transformation of the data, significant correlations were found by univariate analysis between the excretion of a marker of thrombin generation (iF2) and IL-6, DpD and VEGF, as well as between IL-6 and DpD or VEGF excretion. No correlation was found between any marker and serum PSA level. After multivariate analysis, a significant correlation remained between thrombin generation and IL-6 excretion. Analysis of a second urine specimen obtained from 19 of the subjects 1 to 7 months after the first also revealed a significant correlation between thrombin generation and IL-6, DpD, and VEGF excretion. These data provide evidence of a correlation between thrombin generation/coagulation system activation and IL-6 generation in patients with cancer. They provide a rationale for studying the effects of inhibitors of thrombin generation upon the biology of prostate cancer.


Assuntos
Neoplasias da Próstata/sangue , Trombina/biossíntese , Aminoácidos/urina , Biomarcadores/urina , Coagulação Sanguínea , Humanos , Interleucina-6/urina , Masculino , Fragmentos de Peptídeos/urina , Protrombina/urina , Fator A de Crescimento do Endotélio Vascular/urina
11.
Lung Cancer ; 39(2): 221-6, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12581577

RESUMO

Vinorelbine administered in a doublet with cisplatin has become a standard treatment in patients with advanced non-small cell lung cancer (NSCLC). However, carboplatin appears to provide comparable efficacy with a better nonhematologic safety profile than cisplatin. Herein we report the results of a phase I/II trial of weekly vinorelbine and divided-dose carboplatin in patients with stage IIIB/IV NSCLC, Eastern Cooperative Oncology Group performance status < or = 2, and adequate bone marrow. Patients received vinorelbine starting at 20 mg/m(2) (to 25 mg/m(2)) and carboplatin area under the curve (AUC) 2.5 in divided-doses, both given on Days 1 and 8 every 21-day cycle for up to 6 cycles or until disease progression. Dose-limiting toxicity was defined for Cycles 1 and 2. Tumor response and toxicity were assessed using standard criteria. Twenty-one patients with a mean age of 67 years (range, 43-79) and stage IIIB/IV (8/13) disease were enrolled. All but 1 patient were chemotherapy-nai;ve; the majority (n = 20) had good performance status (< or = 1). Seventy-nine courses (median, 4) were administered. The vinorelbine/carboplatin doublet was well tolerated, with 7 courses interrupted or delayed because of toxicity. Toxicities were generally mild and evenly divided between hematologic (i.e., neutropenia) and nonhematologic (i.e., fatigue). No growth factor support was required for hematologic toxicity. There was only one case of grade 2 alopecia, and no cases of > or = grade 2 neurotoxicity. There were 5 (24%) partial responses, and 9 (43%) patients had stable disease. Weekly vinorelbine 25 mg/m(2) and divided-dose carboplatin AUC 2.5 is a well tolerated regimen with activity in advanced NSCLC patients. Further evaluation of this regimen in combination with novel targeted biologic therapy is warranted.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Vimblastina/análogos & derivados , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adenocarcinoma/secundário , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/secundário , Relação Dose-Resposta a Droga , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Segurança , Taxa de Sobrevida , Resultado do Tratamento , Vimblastina/administração & dosagem , Vinorelbina
12.
Endocrinology ; 154(7): 2296-307, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23671262

RESUMO

Androgen deprivation therapy (ADT) is the standard treatment for patients with prostate-specific antigen progression after treatment for localized prostate cancer. An alternative to continuous ADT is intermittent ADT (IADT), which allows recovery of testosterone during off-cycles to stimulate regrowth and differentiation of the regressed prostate tumor. IADT offers patients a reduction in side effects associated with ADT, improved quality of life, and reduced cost with no difference in overall survival. Our previous studies showed that IADT coupled with 5α-reductase inhibitor (5ARI), which blocks testosterone conversion to DHT could prolong survival of animals bearing androgen-sensitive prostate tumors when off-cycle duration was fixed. To further investigate this clinically relevant observation, we measured the time course of testosterone-induced regrowth of regressed LuCaP35 and LNCaP xenograft tumors in the presence or absence of a 5ARI. 5α-Reductase inhibitors suppressed the initial regrowth of regressed prostate tumors. However, tumors resumed growth and were no longer responsive to 5α-reductase inhibition several days after testosterone replacement. This finding was substantiated by bromodeoxyuridine and Ki67 staining of LuCaP35 tumors, which showed inhibition of prostate tumor cell proliferation by 5ARI on day 2, but not day 14, after testosterone replacement. 5α-Reductase inhibitors also suppressed testosterone-stimulated proliferation of LNCaP cells precultured in androgen-free media, suggesting that blocking testosterone conversion to DHT can inhibit prostate tumor cell proliferation via an intracrine mechanism. These results suggest that short off-cycle coupled with 5α-reductase inhibition could maximize suppression of prostate tumor growth and, thus, improve potential survival benefit achieved in combination with IADT.


Assuntos
Inibidores de 5-alfa Redutase/uso terapêutico , Neoplasias da Próstata/induzido quimicamente , Neoplasias da Próstata/tratamento farmacológico , Testosterona/efeitos adversos , Animais , Azasteroides/farmacologia , Azasteroides/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dutasterida , Finasterida/farmacologia , Finasterida/uso terapêutico , Humanos , Imuno-Histoquímica , Letrozol , Masculino , Camundongos , Camundongos Nus , Camundongos SCID , Nitrilas/farmacologia , Nitrilas/uso terapêutico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Triazóis/farmacologia , Triazóis/uso terapêutico
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