RESUMO
AIMS: Determining dihydropyrimidine dehydrogenase (DPD) activity by measuring patient's uracil (U) plasma concentration is mandatory before fluoropyrimidine (FP) administration in France. In this study, we aimed to refine the pre-analytical recommendations for determining U and dihydrouracil (UH2 ) concentrations, as they are essential in reliable DPD-deficiency testing. METHODS: U and UH2 concentrations were collected from 14 hospital laboratories. Stability in whole blood and plasma after centrifugation, the type of anticoagulant and long-term plasma storage were evaluated. The variation induced by time and temperature was calculated and compared to an acceptability range of ±20%. Inter-occasion variability (IOV) of U and UH2 was assessed in 573 patients double sampled for DPD-deficiency testing. RESULTS: Storage of blood samples before centrifugation at room temperature (RT) should not exceed 1 h, whereas cold (+4°C) storage maintains the stability of uracil after 5 hours. For patients correctly double sampled, IOV of U reached 22.4% for U (SD = 17.9%, range = 0-99%). Notably, 17% of them were assigned with a different phenotype (normal or DPD-deficient) based on the analysis of their two samples. For those having at least one non-compliant sample, this percentage increased up to 33.8%. The moment of blood collection did not affect the DPD phenotyping result. CONCLUSION: Caution should be taken when interpreting U concentrations if the time before centrifugation exceeds 1 hour at RT, since it rises significantly afterwards. Not respecting the pre-analytical conditions for DPD phenotyping increases the risk of DPD status misclassification.
Assuntos
Deficiência da Di-Hidropirimidina Desidrogenase , Humanos , Deficiência da Di-Hidropirimidina Desidrogenase/diagnóstico , Di-Hidrouracila Desidrogenase (NADP)/genética , Uracila , Fenótipo , Plasma , FluoruracilaRESUMO
BACKGROUND: Pretherapeutic screening for dihydropyrimidine dehydrogenase (DPD) deficiency is recommended or required prior to the administration of fluoropyrimidine-based chemotherapy. However, the best strategy to identify DPD-deficient patients remains elusive. METHODS: Among a nationwide cohort of 5886 phenotyped patients with cancer who were screened for DPD deficiency over a 3 years period, we assessed the characteristics of both DPD phenotypes and DPYD genotypes in a subgroup of 3680 patients who had completed the two tests. The extent to which defective allelic variants of DPYD predict DPD activity as estimated by the plasma concentrations of uracil [U] and its product dihydrouracil [UH2] was evaluated. RESULTS: When [U] was used to monitor DPD activity, 6.8% of the patients were classified as having DPD deficiency ([U] > 16 ng/ml), while the [UH2]:[U] ratio identified 11.5% of the patients as having DPD deficiency (UH2]:[U] < 10). [U] classified two patients (0.05%) with complete DPD deficiency (> 150 ng/ml), and [UH2]:[U] < 1 identified three patients (0.08%) with a complete DPD deficiency. A defective DPYD variant was present in 4.5% of the patients, and two patients (0.05%) carrying 2 defective variants of DPYD were predicted to have low metabolism. The mutation status of DPYD displayed a very low positive predictive value in identifying individuals with DPD deficiency, although a higher predictive value was observed when [UH2]:[U] was used to measure DPD activity. Whole exon sequencing of the DPYD gene in 111 patients with DPD deficiency and a "wild-type" genotype (based on the four most common variants) identified seven heterozygous carriers of a defective allelic variant. CONCLUSIONS: Frequent genetic DPYD variants have low performances in predicting partial DPD deficiency when evaluated by [U] alone, and [UH2]:[U] might better reflect the impact of genetic variants on DPD activity. A clinical trial comparing toxicity rates after dose adjustment according to the results of genotyping or phenotyping testing to detect DPD deficiency will provide critical information on the best strategy to identify DPD deficiency.
Assuntos
Deficiência da Di-Hidropirimidina Desidrogenase/diagnóstico , Idoso , Estudos de Coortes , Estudos Transversais , Deficiência da Di-Hidropirimidina Desidrogenase/epidemiologia , Deficiência da Di-Hidropirimidina Desidrogenase/genética , Di-Hidrouracila Desidrogenase (NADP)/genética , Di-Hidrouracila Desidrogenase (NADP)/metabolismo , Feminino , França/epidemiologia , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Prevalência , Estudos Retrospectivos , Uracila/análogos & derivados , Uracila/sangue , Uracila/metabolismoRESUMO
In African-American patients with sickle cell disease (SCD), APOL1 G1 and G2 variants are associated with increased risk of sickle cell nephropathy (SCN). To determine the role of APOL1 variants in SCD patients living in Europe, we genotyped 152 SCD patients [aged 30·4 (24·3-36·4) years], mainly of Sub-Saharan African ancestry, for APOL1 G1 and G2 and for variants of four genes with kidney tropism (GSTM1, GSTT1, GSTP1, and HMOX1). Homozygous or double-heterozygous APOL G1 and G2 genotypes were strongly associated with end stage renal disease (P = 0·003) and worse Kidney Disease: Improving Global Outcomes stages (P = 0·001). Further, these genotypes were associated in an age-dependent manner with lower estimated glomerular filtration rate (eGFR, P = 0·008), proteinuria (P = 0·009) and albuminuria (P < 0·001) but not with other SCD complications. Compared to APOL1 G1/wild type (WT), the APOL1 G2/WT genotype was associated with a lower eGFR (P = 0·04) in an age-dependent manner, suggesting that the G2/WT patients are likely to have worse kidney prognosis. Other genes variants analysed were not associated with SCN or other SCD complications. Our data indicate that APOL1 screening should be considered for the management of SCD patients, including those of non-African-American origin, as those with homozygous or double heterozygous variants are clearly at higher risk of SCN.
Assuntos
Albuminúria , Anemia Falciforme , Apolipoproteínas/genética , Variação Genética , Heterozigoto , Homozigoto , Rim/fisiopatologia , Lipoproteínas HDL/genética , Adulto , Negro ou Afro-Americano , Albuminúria/genética , Albuminúria/fisiopatologia , Anemia Falciforme/genética , Anemia Falciforme/fisiopatologia , Apolipoproteína L1 , Feminino , Taxa de Filtração Glomerular , Glutationa S-Transferase pi/genética , Glutationa Transferase/genética , Heme Oxigenase-1/genética , Humanos , MasculinoRESUMO
We report an occurrence of progressive loss of transplant function and ultimately transplant failure after living related kidney transplantation involving monozygotic twin brothers of Afro-Caribbean origin who were both heterozygous for the G1 and G2 kidney disease risk alleles in the APOL1 gene, which encodes apolipoprotein L-I. A 21-year-old man with end-stage kidney disease of unknown cause received a kidney from his brother, who was confirmed as a monozygotic twin by microsatellite analysis. Thirty months after transplantation, the patient presented with proteinuria and decreased estimated glomerular filtration rate; a biopsy of the transplant showed typical focal segmental glomerulosclerosis lesions. He received steroid therapy, but progressed to kidney failure 5 years later. The twin brother had normal kidney function without proteinuria at the time of transplantation; however, 7 years later, he was found to have decreased estimated glomerular filtration rate (40mL/min/1.73m(2)) and proteinuria (protein excretion of 2.5g/d). APOL1 genotyping revealed that both donor and recipient were heterozygous for the G1 and G2 alleles. This case is in stark contrast to the expected course of kidney transplantation in identical twins and suggests a role for APOL1 polymorphisms in both the donor and recipient.
Assuntos
Apolipoproteínas/genética , Doenças em Gêmeos , Transplante de Rim/efeitos adversos , Lipoproteínas HDL/genética , Doadores Vivos , Polimorfismo Genético , Insuficiência Renal Crônica/genética , Gêmeos Monozigóticos/genética , Apolipoproteína L1 , Apolipoproteínas/metabolismo , Biópsia , Seguimentos , Predisposição Genética para Doença , Genótipo , Humanos , Rim/patologia , Lipoproteínas HDL/metabolismo , Masculino , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/cirurgia , Adulto JovemRESUMO
BACKGROUND: Pretherapeutic screening for dihydropyrimidine dehydrogenase (DPD) deficiency based on the measurement of plasma uracil ([U]) is recommended prior to the administration of fluoropyrimidine-based chemotherapy. Cancer patients frequently have impaired kidney function, but the extent to which kidney function decline impacts [U] levels has not been comprehensively investigated. METHODS: We assessed the relationship between DPD phenotypes and estimated glomerular filtration rate (eGFR) in 1751 patients who benefited on the same day from a screening for DPD deficiency by measuring [U] and [UH2]:[U], and an evaluation of eGFR. The impact of a kidney function decline on [U] levels and [UH2]:[U] ratio was evaluated. RESULTS: We observed that [U] was negatively correlated with eGFR, indicating that [U] levels increase as eGFR declines. For each ml/min of eGFR decrease, [U] value increased in average by 0.035 ng/ml. Using the KDIGO classification of chronic kidney disease (CKD), we observed that [U] values >16 ng/ml (DPD deficiency) were measured in 3.6 % and 4.4 % of stage 1 and 2 CKD (normal-high eGFR, >60 ml/min/1.73 m2) patients, but in 6.7 % of stage 3A CKD patients (45 to 59 ml/min/1.73 m2), 25% of stage 3B CKD patients (30 to 44 ml/min/1.73 m2), 22.7% of stage 4 CKD patients (15 to 29 ml/min/1.73 m2 and 26.7% of stage 5 CKD patients (<15 ml/min/1.73 m2). [UH2]:[U] ratios were not impacted by kidney function. CONCLUSION: DPD phenotyping based on the measurement of plasma [U] in patients with decreased eGFR is associated with an exceedingly high rate of false positives when kidney function decline reaches 45 ml/minute/1.73 m2 of eGFR or lower. In this population, an alternative strategy that remain to be evaluated would be to measure the [UH2]:[U] ratio in addition to [U].
Assuntos
Deficiência da Di-Hidropirimidina Desidrogenase , Neoplasias , Insuficiência Renal Crônica , Humanos , Deficiência da Di-Hidropirimidina Desidrogenase/complicações , Deficiência da Di-Hidropirimidina Desidrogenase/diagnóstico , Di-Hidrouracila Desidrogenase (NADP)/genética , Uracila , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/complicações , Neoplasias/complicações , Taxa de Filtração GlomerularRESUMO
Fluoropyrimidine drugs (FP) are the backbone of many chemotherapy protocols for treating solid tumours. The rate-limiting step of fluoropyrimidine catabolism is dihydropyrimidine dehydrogenase (DPD), and deficiency in DPD activity can result in severe and even fatal toxicity. In this review, we survey the evidence-based pharmacogenetics and therapeutic recommendations regarding DPYD (the gene encoding DPD) genotyping and DPD phenotyping to prevent toxicity and optimize dosing adaptation before FP administration. The French experience of mandatory DPD-deficiency screening prior to initiating FP is discussed.
Assuntos
Deficiência da Di-Hidropirimidina Desidrogenase , Humanos , Deficiência da Di-Hidropirimidina Desidrogenase/complicações , Deficiência da Di-Hidropirimidina Desidrogenase/diagnóstico , Deficiência da Di-Hidropirimidina Desidrogenase/genética , Fluoruracila , Antimetabólitos Antineoplásicos/uso terapêutico , Capecitabina , Di-Hidrouracila Desidrogenase (NADP)/genética , Di-Hidrouracila Desidrogenase (NADP)/metabolismoRESUMO
P-glycoprotein (P-gp) is an efflux transporter involved in the bioavailability of many drugs currently on the market. P-gp is responsible for several drug-drug interactions encountered in clinical practice leading to iatrogenic hospital admissions, especially in polypharmacy situations. ABCB1 genotyping only reflects an indirect estimate of P-gp activity. Therefore, it would be useful to identify endogenous biomarkers to determine the P-gp phenotype to predict in vivo activity prior to the initiation of treatment and to assess the effects of drugs on P-gp activity. The objective of this study was to assess changes in plasma lipidome composition among healthy volunteers selected on the basis of their ABCB1 genotype and who received clarithromycin, a known inhibitor of P-gp. Untargeted lipidomic analysis based on liquid chromatography-tandem mass spectrometry was performed before and after clarithromycin administration. Our results revealed changes in plasma levels of some ceramides (Cers) {Cer(d18:1/22:0), Cer(d18:1/22:1), and Cer(d18:1/20:0) by ~38% (p < 0.0001), 13% (p < 0.0001), and 13% (p < 0.0001), respectively} and phosphatidylcholines (PCs) {PC(17:0/14:1), PC(16:0/18:3), and PC(14:0/18:3) by ~24% (p < 0.001), 10% (p < 0.001), and 23.6% (p < 0.001)} associated with both ABCB1 genotype and clarithromycin intake. Through the examination of plasma lipids, our results highlight the relevance of untargeted lipidomics for studying in vivo P-gp activity and, more generally, to safely phenotyping transporters.
Assuntos
Claritromicina , Lipidômica , Humanos , Claritromicina/farmacologia , Voluntários Saudáveis , Biomarcadores , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/genéticaRESUMO
BACKGROUND: Lipin-1 deficiency is a life-threatening disease that causes severe rhabdomyolysis (RM) and chronic symptoms associated with oxidative stress. In the absence of treatment, Hydroxychloroquine sulfate (HCQ) was administered to patients off label use on a compassionate basis in order to improve their physical conditions. METHODS: Eleven patients with LPIN1 mutations were treated with HCQ. Clinical and biological efficacy and tolerance were assessed, including pain and quality of life, physical capacities, cardiopulmonary parameters, creatine kinase levels and plasma proinflammatory cytokines. To explore a dose-dependent effect of HCQ, primary myoblasts from 4 patients were incubated with various HCQ concentrations in growth medium (GM) or during starvation (EBSS medium) to investigate autophagy and oxidative stress. FINDINGS: Under HCQ treatment, patient physical capacities improved. Abnormal cardiac function and peripheral muscle adaptation to exercise were normalized. However, two patients who had the highest mean blood HCQ concentrations experienced RM. We hypothesized that HCQ exerts deleterious effects at high concentrations by blocking autophagy, and beneficial effects on oxidative stress at low concentrations. We confirmed in primary myoblasts from 4 patients that high in vitro HCQ concentration (10 µM) but not low concentration (1 µM and 0.1 µM) induced autophagy blockage by modifying endolysosomal pH. Low HCQ concentration (1 µM) prevented reactive oxygen species (ROS) and oxidized DNA accumulation in myoblasts during starvation. INTERPRETATION: HCQ improves the condition of patients with lipin-1 deficiency, but at low concentrations. In vitro, 1 µM HCQ decreases oxidative stress in myoblasts whereas higher concentrations have a deleterious effect by blocking autophagy.
Assuntos
Hidroxicloroquina , Qualidade de Vida , Humanos , Hidroxicloroquina/farmacologia , Hidroxicloroquina/uso terapêutico , Citocinas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Fosfatidato Fosfatase/genéticaRESUMO
Thrombosis is a hallmark of severe COVID-19. Alpha-1-antitrypsin (AAT), an inflammation-inducible serpin with anti-inflammatory, tissue protective and anticoagulant properties may be involved in severe COVID-19 pathophysiology including thrombosis onset. In this study, we examined AAT ability to predict occurrence of thrombosis and in-hospital mortality during COVID-19. To do so, we performed a monocentric cross-sectional study of 137 hospitalized patients with COVID-19 of whom 56 (41%) were critically ill and 33 (22.4%) suffered from thrombosis during hospitalization. We measured AAT and IL-6 plasma levels in all patients and phenotyped AAT in a subset of patients with or without thrombosis paired for age, sex and COVID-19 severity. We observed that AAT levels at admission were higher in both non-survivors and thrombosis patients than in survivors and non-thrombosis patients. AAT: IL-6 ratio was lower in non-survivors and thrombosis patients. In a logistic regression multivariable analysis model adjusted on age, BMI and D-dimer levels, a higher AAT: IL-6 was a protective factor of both in-hospital mortality (Odds ratio, OR: 0.07 95%CI [0.02-0.25], p < 0.001) and thrombosis (OR 0.36 95%CI [0.14-0.82], p = 0.02). AAT phenotyping did not show a higher proportion of AAT abnormal variants in thrombosis patients.Our findings suggest an insufficient production of AAT regarding inflammation intensity during severe COVID-19. AAT appeared as a powerful predictive marker of severity, mortality and thrombosis mirroring the imbalance between harmful inflammation and protective counter-balancing mechanism in COVID-19. Restoring the balance between AAT and inflammation could offer therapeutic opportunities in severe COVID-19.
Assuntos
COVID-19 , Mortalidade Hospitalar , Interleucina-6 , Trombose , alfa 1-Antitripsina , Humanos , COVID-19/complicações , COVID-19/mortalidade , Estudos Transversais , Inflamação , Interleucina-6/sangue , alfa 1-Antitripsina/sangue , Trombose/virologiaRESUMO
High interindividual variability (IIV) of the clinical response to epidermal growth factor receptor (EGFR) inhibitors such as osimertinib in non-small-cell lung cancer (NSCLC) might be related to the IIV in plasma exposure. The aim of this study was to evaluate the exposure−response relationship for toxicity and efficacy of osimertinib in unselected patients with advanced EGFR-mutant NSCLC. This retrospective analysis included 87 patients treated with osimertinib. Exposure−toxicity analysis was performed in the entire cohort and survival analysis only in second-line patients (n = 45). No significant relationship between occurrence of dose-limiting toxicity and plasma exposure was observed in the entire cohort (p = 0.23, n = 86). The median overall survival (OS) was approximately two-fold shorter in the 4th quartile (Q4) of osimertinib trough plasma concentration (>235 ng/mL) than in the Q1−Q3 group (12.2 months [CI95% = 8.0−not reached (NR)] vs. 22.7 months [CI95% = 17.1−34.1]), but the difference was not statistically significant (p = 0.15). To refine this result, the exposure−survival relationship was explored in a cohort of 41 NSCLC patients treated with erlotinib. The Q4 erlotinib exposure group (>1728 ng/mL) exhibited a six-fold shorter median OS than the Q1−Q3 group (4.8 months [CI95% = 3.3-NR] vs. 22.8 months (CI95% = 10.6−37.4), p = 0.00011). These results suggest that high exposure to EGFR inhibitors might be related to worse survival in NSCLC patients.
RESUMO
BACKGROUND: Pretherapeutic screening for dihydropyrimidine dehydrogenase (DPD) deficiency is recommended prior to the administration of fluoropyrimidine-based chemotherapy. However, the best strategy to identify DPD deficiency in End Stage Renal Disease (ESRD) patients is unknown. METHODS: We assessed the characteristics of both DPD phenotypes and DPYD genotypes in 20 dialyzed patients before and after dialysis session. The extent to which the concentrations of uracil [U] and dihydrouracil [UH2] were affected by dialysis was evaluated. RESULTS: Mean [U] was 14 ± 3.3 ng/ml before the dialysis session, and 7.9 ± 2.7 ng/ml after. Notably, mean [U] in 119 non-ESRD patients during the same timeline was 8.7 ± 3.9 ng/ml, which is similar to [U] values after dialysis session (p = 0.38). [U] values > 16 ng/ml were measured in 4 ESRD patients (20%), whereas the rate was 3.3% in the non-ESRD cohort. Whole gene sequencing did not reveal DPYD deleterious allelic variants in the 4 ESRD patients with [U] values > 16 ng/ml. The profile of [UH2] values during dialysis was similar to that of [U]: 385 ± 86 ng/ml before, and 185 ± 62 ng/ml after (mean reduction rate 42.5%). Thus, [UH2]:[U] ratio remained unaffected by dialysis, and was similar to the values in non-ESRD patients (22.4 ± 7.1). CONCLUSION: Phenotyping based on measuring plasma [U] before a dialysis sessions in ESRD patients is associated with an unacceptable high rate of false positives. The optimal strategy for the identification of patients with DPD deficiency in this population would be the monitor the [UH2]:[U] ratio, which remains unaffected.
Assuntos
Deficiência da Di-Hidropirimidina Desidrogenase/diagnóstico , Di-Hidrouracila Desidrogenase (NADP)/metabolismo , Falência Renal Crônica/terapia , Programas de Rastreamento/métodos , Diálise Renal/efeitos adversos , Uracila/sangue , Estudos de Casos e Controles , Deficiência da Di-Hidropirimidina Desidrogenase/enzimologia , Deficiência da Di-Hidropirimidina Desidrogenase/etiologia , Reações Falso-Positivas , Seguimentos , Humanos , Falência Renal Crônica/patologia , Estudos ProspectivosRESUMO
Idiosyncratic toxicity is a rare adverse drug-induced reaction. It may occur in a small number of patients, is often serious and may lead to patients' death. Preclinical and clinical drug development fail to predict idiosyncratic post-marketing problems. Idiosyncratic adverse reaction could be prevented either by detection of predisposed patients or use of biomarkers that could predict adverse reactions induced by a drug. The identification of biomarkers that could help predict idiosyncratic reaction requires highthrouhput technologies such as << omics >> (genomic, transcriptomic, proteomic, metabonomic), which are methods allowing screening and evaluation of extensive data and are suitable for untargeted analyses of different models. This review presents genomic and transcriptomic data. The genomic studies identified genetic risk factor that could be used in clinical practice to prevent idiosyncratic reaction in predisposed patients. The transcriptomic studies gave information on biological processes altered by a treatment with a drug. Understanding toxicity mechanisms could lead to identification of toxicity biomarkers.
Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Perfilação da Expressão Gênica , Genômica , Metaboloma , Proteoma , Antígenos/imunologia , Linfócitos B/imunologia , HumanosRESUMO
Aim: To assess rare TPMT variants in patients carrying a deficient phenotype not predicted by the four more frequent genotypes (*2, *3A, *3B and *3C). Materials & methods: Next-generation sequencing of TPMT in 39 patients with a discordant genotype. Results: None of the variants identified explained the discordances assuming that they are of uncertain significance according to the Clinical Pharmacogenetics Implementation Consortium classification. Two unknown variants were detected and predicted to result in a splicing defect. We show that TPMT*16 and TMPT*21 are defective alleles, and TPMT*8 and TPMT*24 are associated with a normal activity. Conclusion: Whole-exon sequencing for rare TPMT mutations has a low diagnostic yield. A reassessment of the functional impact of rare variants of uncertain significance is a critical issue.
Assuntos
Metiltransferases/deficiência , Metiltransferases/genética , Alelos , Éxons , Variação Genética , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Íntrons/genética , Mutação , Fenótipo , Polimorfismo Genético , Sequenciamento do ExomaRESUMO
Cytochrome P450 2C9 (P450 2C9) is one of the most important P450 isoforms in the human liver, as it metabolizes numerous exogenous and endogenous substrates. Moreover, it is inducible by several compounds, such as rifampicin, phenobarbital, and NSAIDs (nonsteroidal anti-inflammatories). The aim of this study was to investigate the global cellular consequences of P450 2C9 overexpression at the transcriptional level using an untargeted approach: pangenomic microarrays. Recombinant adenovirus was used to express P450 2C9 instead of an inducer to prevent a per se effect of inducer or its metabolites. P450 2C9 overexpression induced endoplasmic reticulum (ER) stress and regulated genes implicated in the unfolded protein response (UPR) as heat shock protein (HSP) (we studied particurlarly HSPA5 and HSPB1) and in the endoplasmic reticulum associated degradation (ERAD) system as Sec61 and ubiquitin and proteasome pathways. UPR and ERAD are two mechanisms of adaptative response to ER stress. Moreover, activation of Akt was observed in HepG2 cells that overexpress P450 2C9 and might participate in the cellular adaptive response to stress, thus leading to the activation of cell survival pathways. UPR and ERAD should be caused by accumulation of native and misfolded P450 2C9 protein. Our results indicated that P450 2C9 overexpression did not lead to toxicity but induced an ER stress due to protein overexpression rather than mono-oxygenase activity. The ER stress triggered activation of the adaptative response and of pathways leading to cell survival.
Assuntos
Hidrocarboneto de Aril Hidroxilases/metabolismo , Perfilação da Expressão Gênica , Hidrocarboneto de Aril Hidroxilases/genética , Carcinoma Hepatocelular , Sobrevivência Celular , Citocromo P-450 CYP2C9 , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Chaperona BiP do Retículo Endoplasmático , Proteínas de Choque Térmico HSP27/genética , Proteínas de Choque Térmico HSP27/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Chaperonas Moleculares , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Canais de Translocação SEC , Transcrição Gênica , Células Tumorais Cultivadas , Ubiquitina/genética , Ubiquitina/metabolismoAssuntos
Deficiência da Di-Hidropirimidina Desidrogenase , Fluoruracila , Humanos , Antimetabólitos Antineoplásicos/efeitos adversos , Antimetabólitos Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Deficiência da Di-Hidropirimidina Desidrogenase/complicações , Evolução Fatal , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversosRESUMO
PURPOSE: Intravenous ketamine is often prescribed in severe neuropathic pain. Oral N-methyl-D-aspartate receptor (NMDAR) antagonists might prolong pain relief, reducing the frequency of ketamine infusions and hospital admissions. This clinical trial aimed at assessing whether oral dextromethorphan or memantine might prolong pain relief after intravenous ketamine. PATIENTS AND METHODS: A multicenter randomized controlled clinical trial included 60 patients after ketamine infusion for refractory neuropathic pain. Dextromethorphan (90 mg/day), memantine (20 mg/day) or placebo was given for 12 weeks (n=20 each) after ketamine infusion. The primary endpoint was pain intensity at one month. Secondary endpoints included pain, sleep, anxiety, depression, cognitive function and quality of life evaluations up to 12 weeks. RESULTS: At 1 month, dextromethorphan maintained ketamine pain relief (Numeric Pain Scale: 4.01±1.87 to 4.05±2.61, p=0.53) and diminished pain paroxysms (p=0.03) while pain intensity increased significantly with memantine and placebo (p=0.04). At 3 months, pain remained lower than at inclusion (p=0.001) and was not significantly different in the three groups. Significant benefits were observed on cognitive-affective domains and quality of life for dextromethorphan and memantine (p<0.05). CONCLUSIONS: Oral dextromethorphan given after ketamine infusion extends pain relief during one month and could help patients to better cope with pain. Future studies should include larger populations stratified on pharmacogenetics screening. Optimization of an oral drug that could extend ketamine antihyperalgesia, with fewer hospital admissions, remains a prime challenge in refractory neuropathic pain.
Assuntos
Analgesia , Dextrometorfano/uso terapêutico , Ketamina/uso terapêutico , Memantina/uso terapêutico , Neuralgia/tratamento farmacológico , Administração Oral , Adulto , Idoso , Dextrometorfano/administração & dosagem , Feminino , Humanos , Infusões Intravenosas , Ketamina/administração & dosagem , Masculino , Memantina/administração & dosagem , Pessoa de Meia-IdadeRESUMO
Fluoropyrimidines (FU) are still the most prescribed anticancer drugs for the treatment of solid cancers. However, fluoropyrimidines cause severe toxicities in 10 to 40% of patients and toxic deaths in 0.2 to 0.8% of patients, resulting in a real public health problem. The main origin of FU-related toxicities is a deficiency of dihydropyrimidine dehydrogenase (DPD), the rate-limiting enzyme of 5-FU catabolism. DPD deficiency may be identified through pharmacogenetics testing including phenotyping (direct or indirect measurement of enzyme activity) or genotyping (detection of inactivating polymorphisms on the DPYD gene). Approximately 3 to 15% of patients exhibit a partial deficiency and 0.1 to 0.5% a complete DPD deficiency. Currently, there is no regulatory obligation for DPD deficiency screening in patients scheduled to receive a fluoropyrimidine-based chemotherapy. Based on the levels of evidence from the literature data and considering current French practices, the Group of Clinical Pharmacology in Oncology (GPCO)-UNICANCER and the French Network of Pharmacogenetics (RNPGx) recommend the following: (1) to screen DPD deficiency before initiating any chemotherapy containing 5-FU or capecitabine; (2) to perform DPD phenotyping by measuring plasma uracil (U) concentrations (possibly associated with dihydrouracil/U ratio), and DPYD genotyping (variants *2A, *13, p.D949V, HapB3); (3) to reduce the initial FU dose (first cycle) according to DPD status, if needed, and further, to consider increasing the dose at subsequent cycles according to treatment tolerance. In France, 17 public laboratories currently undertake routine screening of DPD deficiency.
Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Capecitabina/uso terapêutico , Deficiência da Di-Hidropirimidina Desidrogenase/complicações , Fluoruracila/uso terapêutico , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/efeitos adversos , Capecitabina/administração & dosagem , Capecitabina/efeitos adversos , Deficiência da Di-Hidropirimidina Desidrogenase/diagnóstico , Di-Hidrouracila Desidrogenase (NADP)/análise , Di-Hidrouracila Desidrogenase (NADP)/genética , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , França , Humanos , Neoplasias/tratamento farmacológico , Fenótipo , Guias de Prática Clínica como Assunto , Pirimidinas/administração & dosagem , Pirimidinas/efeitos adversos , Pirimidinas/uso terapêutico , Uracila/sangueRESUMO
Lynch syndrome is a hereditary predisposition to many tumors, in the forefront of which endometrial cancer in women. It is related to the mutation of a mismatch repair gene, involved in DNA mismatch repair. This mutation leads to a loss of expression of the corresponding protein, and to genome instability in tumor cells. Cumulative risk at the age of 70 years is over 40 %. Endometrial cancers related to Lynch syndrome are most of the time sentinel (They reveal the predisposition in half of families.) and are characterized by young age at onset (before 60 years) and low body mass index compared with patients presenting sporadic tumors. Pathological tumor characteristics are debated but it seems to be two types of tumors according to age, older patients having standard tumors and younger ones more aggressive pattern. Endometrial cancers related to Lynch syndrome can be synchronous of ovarian cancer. Therapeutic management does not present any particularity. Conservative treatment can be considered more frequently due to young age of patients but has to respect usual guidelines. Prognosis of these tumors is controversial. Gynaecological screening, although its benefit has not been proved, appears crucial in this population, as well as prophylactic surgery, which remains the best prevention.
Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Reparo de Erro de Pareamento de DNA , Neoplasias do Endométrio/genética , Fatores Etários , Idoso , Neoplasias Colorretais Hereditárias sem Polipose/patologia , Neoplasias Colorretais Hereditárias sem Polipose/terapia , Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/terapia , Feminino , Humanos , Instabilidade de Microssatélites , Pessoa de Meia-Idade , MutaçãoRESUMO
This phase I, pilot clinical study was designed to evaluate the safety and the pharmacokinetic (PK) profiles of the CIME (Metabolic Identity Card) combination of ten drugs, with a view to its use as a phenotyping cocktail. Ten healthy Caucasian subjects were orally dosed with the CIME combination (caffeine-CYP1A2, repaglinide-CYP2C8, tolbutamide-CYP2C9, omeprazole-CYP2C19, dextromethorphan-CYP2D6, midazolam-CYP3A, acetaminophen-UGT1A1, 6&9 and 2B15, digoxin-P-gp, rosuvastatin-OATP1B1&3 and memantine-active renal transport). Blood was collected over 3 days and on day 7. CIME probes and relevant metabolites were assayed by LC-MS/MS and PK parameters were calculated. Main results were: (1) good safety with reversible mild or moderate adverse effects, (2) an analytical method able to quantify simultaneously the 10 probes and the major metabolites, (3) calculation of PK parameters for all probes in general agreed with published values, and (4) identification of the low CYP2D6 metabolizer. This pilot study showed that the CIME combination was well tolerated and that its pharmacokinetics could be accurately measured in healthy volunteers. This combination can now confidently be checked for sensitivity and specificity and for lack of interaction to be validated as a phenotyping cocktail.