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1.
Toxicol Appl Pharmacol ; 253(2): 130-6, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21466820

RESUMO

Interferon α (IFNα) is used to treat malignancies and chronic viral infections. It has been found to decrease the rate of drug metabolism by acting on cytochrome P450 enzymes, but no studies have investigated the consequences of IFNα treatment on the CYP3A4 isoform, responsible for the metabolism of a majority of drugs. In this study, we have examined the effect of IFNα on CYP3A4 catalytic activity and expression in human hepatoma cells. We found that IFNα inhibits CYP3A4 activity and rapidly down-regulates the expression of CYP3A4, independent of de novo protein synthesis. Pharmacologic inhibitors and a dominant-negative mutant expression plasmid were used to dissect the molecular pathway required for CYP3A4 suppression, revealing roles for Jak1 and Stat1 and eliminating the involvement of the p38 mitogen-activated and extracellular regulated kinases. Treatment of hepatoma cells with IFNα did not affect the nuclear localization or relative abundance of Sp1 and Sp3 transcription factors, suggesting that the suppression of CYP3A4 by IFNα does not result from inhibitory Sp3 out-competing Sp1. To our knowledge, this is the first report that IFNα down-regulates CYP3A4 expression largely through the JAK-STAT pathway. Since IFNα suppresses CYP3A4 expression, caution is warranted when IFNα is administered in combination with CYP3A4 substrates to avoid the occurrence of adverse drug interactions.


Assuntos
Inibidores do Citocromo P-450 CYP3A , Interferon-alfa/farmacologia , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Células Hep G2 , Humanos , Janus Quinase 1/fisiologia , Regiões Promotoras Genéticas , Biossíntese de Proteínas , RNA Mensageiro/análise , Fator de Transcrição STAT1/fisiologia
2.
Can Urol Assoc J ; 15(8): 269-279, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33443481

RESUMO

INTRODUCTION: Approximately 50% of patients with non-metastatic prostate cancer are treated with radical prostatectomy (RP). While some men will be cured with surgery alone, a substantial proportion will experience cancer recurrence. Androgen-directed therapy (ADT) is an effective adjuvant therapy for patients treated with prostate radiation. Comparatively, the efficacy of ADT in surgical patients has not been well-studied. METHODS: A systematic search of MEDLINE, Embase, and the Cochrane Library from inception to July 2020 was performed. Randomized trials comparing ADT with RP vs. prostatectomy alone in patients with clinically localized prostate cancer were included. Neoadjuvant ADT and adjuvant ADT interventions were assessed separately. The primary outcomes were cancer recurrence-free survival (RFS) and overall survival (OS). Pathological outcomes following neoadjuvant ADT were also evaluated. RESULTS: Fifteen randomized trials met eligibility criteria; 11 evaluated neoadjuvant ADT (n=2322) and four evaluated adjuvant ADT (n=5205). Neoadjuvant ADT (three months of treatment) did not improve RFS (hazard ratio [HR] 0.90, 95% confidence interval [CI] 0.74-1.11) or OS (HR 1.22, 95% CI 0.62-2.41). Neoadjuvant ADT significantly decreased the risk of positive surgical margins (relative risk [RR] 0.48, 95% CI 0.41-0.56) and extraprostatic tumor extension (RR 0.75, 95% CI 0.64-0.89). Adjuvant ADT improved RFS (HR 0.65, 95% CI 0.45-0.93) but did not improve OS (HR 1.02, 95% CI 0.84-1.24). CONCLUSIONS: Neoadjuvant ADT causes a pathological downstaging of prostate tumors but has not been found to delay cancer recurrence nor extend survival. Few studies have evaluated adjuvant ADT. Trials are needed to determine the benefits and harms of intermediate- or long-term adjuvant ADT for RP patients.

3.
Urol Oncol ; 36(9): 400.e1-400.e5, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30064934

RESUMO

INTRODUCTION: Surgical site infections (SSI) are common after radical cystectomy. The objectives of this study were to evaluate if female sex is associated with postoperative SSI and if experiencing an SSI was associated with subsequent adverse events. METHODS: This was a historical cohort study of radical cystectomy patients from the American College of Surgeons' National Surgical Quality Improvement Program database between 2006 and 2016. The primary outcome was development of a SSI (superficial, deep, or organ/abdominal space) within 30 days of surgery. Multivariable logistic regression analyses were performed to determine the association between sex and other patient/procedural factors with SSI. Female patients with SSI were also compared to those without SSI to determine risk of subsequent adverse events. RESULTS: A total of 9,275 radical cystectomy patients met the inclusion criteria. SSI occurred in 1,277(13.7%) patients, 308 (16.4%) females and 969 (13.1%) males (odds ratio = 1.27; 95% confidence interval 1.10-1.47; P = 0.009). Infections were superficial in 150 (8.0%) females versus 410 (5.5%) males (P < 0.0001), deep in 40 (2.1%) females versus 114 (1.5%) males (P = 0.07), and organ/abdominal space in 118 (6.2%) females versus 445 (6.0%) males (P = 0.66). On multivariable analysis, female sex was independently associated with SSI (odds ratio = 1.21 confidence interval 1.01-1.43 P = 0.03). Females who experience SSI had higher probability of developing other complications including wound dehiscence, septic shock, and need for reoperation (all P < 0.05). CONCLUSIONS: Female sex is an independent risk factor for SSI following radical cystectomy. More detailed study of patient factors, pathogenic microbes, and treatment factors are needed to prescribe the best measures for infection prophylaxis.


Assuntos
Cistectomia/efeitos adversos , Infecção da Ferida Cirúrgica/etiologia , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Infecção da Ferida Cirúrgica/patologia
4.
PLoS One ; 5(6): e11031, 2010 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-20544007

RESUMO

BACKGROUND: Recombinant interferon treatment can result in several common side effects including fever and injection-site pain. Patients are often advised to use acetaminophen or other over-the-counter pain medications as needed. Little is known regarding the transcriptional changes induced by such co-administration. METHODOLOGY/PRINCIPAL FINDINGS: We tested whether the administration of acetaminophen causes a change in the response normally induced by interferon-beta treatment. CD-1 mice were administered acetaminophen (APAP), interferon-beta (IFN-beta) or a combination of IFN-beta+APAP and liver and serum samples were collected for analysis. Differential gene expression was determined using an Agilent 22 k whole mouse genome microarray. Data were analyzed by several methods including Gene Ontology term clustering and Gene Set Enrichment Analysis. We observed a significant change in the transcription profile of hepatic cells when APAP was co-administered with IFN-beta. These transcriptional changes included a marked up-regulation of genes involved in signal transduction and cell differentiation and down-regulation of genes involved in cellular metabolism, trafficking and the IkappaBK/NF-kappaB cascade. Additionally, we observed a large decrease in the expression of several IFN-induced genes including Ifit-3, Isg-15, Oasl1, Zbp1 and predicted gene EG634650 at both early and late time points. CONCLUSIONS/SIGNIFICANCE: A significant change in the transcriptional response was observed following co-administration of IFN-beta+APAP relative to IFN-beta treatment alone. These results suggest that administration of acetaminophen has the potential to modify the efficacy of IFN-beta treatment.


Assuntos
Acetaminofen/farmacologia , Interferon beta/farmacologia , Transcrição Gênica/efeitos dos fármacos , Acetaminofen/efeitos adversos , Animais , Regulação para Baixo , Perfilação da Expressão Gênica , Fígado/efeitos dos fármacos , Masculino , Camundongos , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Recombinantes/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima
5.
PLoS One ; 4(12): e8350, 2009 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-20020057

RESUMO

BACKGROUND: Influenza viruses cause serious infections that can be prevented or treated using vaccines or antiviral agents, respectively. While vaccines are effective, they have a number of limitations, and influenza strains resistant to currently available anti-influenza drugs are increasingly isolated. This necessitates the exploration of novel anti-influenza therapies. METHODOLOGY/PRINCIPAL FINDINGS: We investigated the potential of aurintricarboxylic acid (ATA), a potent inhibitor of nucleic acid processing enzymes, to protect Madin-Darby canine kidney cells from influenza infection. We found, by neutral red assay, that ATA was protective, and by RT-PCR and ELISA, respectively, confirmed that ATA reduced viral replication and release. Furthermore, while pre-treating cells with ATA failed to inhibit viral replication, pre-incubation of virus with ATA effectively reduced viral titers, suggesting that ATA may elicit its inhibitory effects by directly interacting with the virus. Electron microscopy revealed that ATA induced viral aggregation at the cell surface, prompting us to determine if ATA could inhibit neuraminidase. ATA was found to compromise the activities of virus-derived and recombinant neuraminidase. Moreover, an oseltamivir-resistant H1N1 strain with H274Y was also found to be sensitive to ATA. Finally, we observed additive protective value when infected cells were simultaneously treated with ATA and amantadine hydrochloride, an anti-influenza drug that inhibits M2-ion channels of influenza A virus. CONCLUSIONS/SIGNIFICANCE: Collectively, these data suggest that ATA is a potent anti-influenza agent by directly inhibiting the neuraminidase and could be a more effective antiviral compound when used in combination with amantadine hydrochloride.


Assuntos
Ácido Aurintricarboxílico/farmacologia , Betainfluenzavirus/efeitos dos fármacos , Betainfluenzavirus/enzimologia , Inibidores Enzimáticos/farmacologia , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza A/enzimologia , Neuraminidase/antagonistas & inibidores , Amantadina/farmacologia , Animais , Linhagem Celular , Meios de Cultura , Citoproteção/efeitos dos fármacos , Cães , Farmacorresistência Viral/efeitos dos fármacos , Sinergismo Farmacológico , Corpos de Inclusão Viral/efeitos dos fármacos , Corpos de Inclusão Viral/ultraestrutura , Vírus da Influenza A/fisiologia , Vírus da Influenza A/ultraestrutura , Betainfluenzavirus/fisiologia , Betainfluenzavirus/ultraestrutura , Oseltamivir/farmacologia , RNA Viral/análise , Inativação de Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
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