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1.
Nihon Yakurigaku Zasshi ; 156(5): 303-311, 2021.
Artigo em Japonês | MEDLINE | ID: mdl-34470936

RESUMO

Cabozantinib (CAB) is a receptor tyrosine kinase inhibitor with activity against MET, VEGFR2, and AXL, among others. This drug is considered to exert excellent antitumor effects by inhibiting these targets simultaneously. Significant improvement in the primary endpoint (overall survival or PFS) were observed in patients on CAB in comparison with controls in a phase-III study in patients with renal cell carcinoma, progressed after treatment with anti-angiogenic agents, and in another phase-III study in patients with previously treated, advanced hepatocellular carcinoma. These results led to the approval of CAB in Japan in 2020 as a therapeutic agent for unresectable or metastatic renal cell carcinoma and unresectable hepatocellular carcinoma progressed after cancer chemotherapy, under the trade name of CABOMETYX® (20 mg, and 60 mg tablets). It has been suggested that CAB may modulate the immune system in favor of antitumor immunity and combined use with PD-1 checkpoint inhibitors may exert a synergistic effect. In a phase-III study that examined the efficacy of combination therapy with CAB and nivolumab in treatment-naive patients with advanced renal cell carcinoma, progression-free survival was significantly increased in patients on combination therapy over patients on sunitinib monotherapy. Three global phase-III clinical studies of combination therapy with atezolizumab and CAB in patients with non-small cell lung cancer, castration-resistant prostate cancer, and renal cell carcinoma, are in progress to confirm the efficacy of CAB.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Renais , Neoplasias Renais , Neoplasias Hepáticas , Neoplasias Pulmonares , Anilidas , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma de Células Renais/tratamento farmacológico , Ensaios Clínicos Fase III como Assunto , Humanos , Neoplasias Renais/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Piridinas
2.
Anticancer Res ; 41(9): 4377-4385, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34475057

RESUMO

BACKGROUND/AIM: Expression of pleckstrin homology-like domain family A member 2 (PHLDA2) has been reported to be suppressed or activated in several cases of malignant tumors. However, its apoptotic regulatory mechanism and role in gastric cancer are not understood. This study examined the role of PHLDA2 in apoptosis in gastric cancer. MATERIALS AND METHODS: We used cell culture, western blotting, semiquantitative reverse transcription polymerase chain reaction, MTT assays, and PHLDA2 knockdown with short hairpin RNA (shRNA). RESULTS: To identify the pathway associated with HGF-induced PHLDA2 up-regulation, the cells were treated with PI3-kinase inhibitor (LY294002), MEK inhibitor (PD098059), or p38 inhibitor (SB203580) and then analyzed by western blotting. HGF-mediated changes in PHLDA2 protein levels were only decreased by LY294002. PHLDA2-shRNA cells showed decreased levels of p53 and increased levels of pAKT. Furthermore, HGF-induced cell proliferation and in vitro invasion were increased in PHLDA2 knockdown cells and HGF-induced cell apoptosis was increased in PHLDA2 knockdown cells. CONCLUSION: PHLDA2 plays a role in gastric cancer tumorigenesis by inhibiting apoptosis through the PI3K/AKT pathway.


Assuntos
Fator de Crescimento de Hepatócito/metabolismo , Proteínas Nucleares/metabolismo , Neoplasias Gástricas/metabolismo , Regulação para Cima , Apoptose , Linhagem Celular Tumoral , Cromonas/farmacologia , Flavonoides/farmacologia , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Imidazóis , Morfolinas/farmacologia , Proteínas Nucleares/genética , Análise de Sequência com Séries de Oligonucleotídeos , Piridinas
3.
Eur Rev Med Pharmacol Sci ; 25(16): 5310-5317, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34486707

RESUMO

OBJECTIVE: The outbreak of coronavirus disease 2019 (COVID-19) has affected the treatment of cancer patients, with particular regard to the management of both chemotherapy and side effects. Chemotherapy-induced nausea and vomiting (CINV) are amongst the most troublesome side effects that impair patients' adherence to treatments and their quality of life (QoL). NEPA (Akynzeo®), is an oral fixed-dose combination of netupitant [a neurokinin-1 receptor antagonist (NK1RA), 300 mg] and palonosetron [(5-hydroxytryptamine (serotonin or 5HT) type3 receptor antagonist (5HT3RA), 0.5 mg] which has been shown to be effective in preventing CINV. PATIENTS AND METHODS: This prospective study started before the outbreak of COVID-19 and was carried out during the pandemic period. The aim was to evaluate the efficacy and safety of a single oral dose NEPA plus 12 mg of dexamethasone (DEX) in patients treated with Folfoxiri plus Bevacizumab and Folfirinox. The patients were diagnosed with advanced colorectal cancer (CRC) or advanced pancreatic ductal adenocarcinoma (PDAC). They were divided into two groups: naïve patients and patients previously treated with serotonin receptor antagonists (5HT3-RA) and neurokin-1 receptor antagonists (NK1-RA). RESULTS: During the overall phase, the complete response (CR) rate was 96.8% in naïve patients treated with Folfoxiri plus Bevacizumab, and 94.6% in patients treated with Folfirinox. During the acute and delayed phases, the CR rate was 92.8% and 94.2%, with Folfoxiri and Bevacizumab, as well as 96.2% and 94.6%, with Folfirinox. There was no adequate control of CINV events in patients on antiemetic prophylaxis with 5HT3-RA or NK1-RA associated with cortisone. During the overall phase, the CR rate was 74.6% with Folfoxiri plus Bevacizumab and 75.8% with Folfirinox. During the acute and delayed phases, the CR rate was 72.5% and 74.8% with Folfoxiri plus Bevacizumab, as well as 75.2% and 74.6% with Folfirinox. CONCLUSIONS: This study has shown the therapeutic benefits of NEPA in the management and prophylaxis of CINV events, both in naive patients and patients previously treated with 5HT3-RA and NK1-RA. In addition, NEPA has been shown to be safe, both before and during the COVID-19 pandemic.


Assuntos
Antieméticos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Palonossetrom/uso terapêutico , Piridinas/uso terapêutico , Idoso , Antieméticos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Bevacizumab/administração & dosagem , COVID-19 , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/uso terapêutico , Humanos , Irinotecano/administração & dosagem , Irinotecano/uso terapêutico , Leucovorina/administração & dosagem , Leucovorina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Náusea/prevenção & controle , Oxaliplatina/administração & dosagem , Oxaliplatina/uso terapêutico , Palonossetrom/administração & dosagem , Pandemias , Estudos Prospectivos , Piridinas/administração & dosagem , Vômito/prevenção & controle
4.
Tidsskr Nor Laegeforen ; 1412021 09 07.
Artigo em Norueguês | MEDLINE | ID: mdl-34505490

RESUMO

BACKGROUND: Activating RET fusions are oncogenic drivers in multiple cancers and are identified in 1-2 % of non-small cell lung cancers (NSCLC). Selpercatinib and pralsetinib are tyrosine kinase inhibitors selectively targeting RET and with clinical activity in RET-positive NSCLC. CASE PRESENTATION: A male never-smoker in his forties was diagnosed with advanced lung adenocarcinoma. With negative tests for EGFR mutations, ROS1 and ALK rearrangements, he was treated with a combination of chemotherapy and an immune checkpoint inhibitor. Upon progression a rebiopsy analysed by next generation sequencing (NGS) revealed a KIF5B-RET fusion. He received treatment with pralsetinib through a compassionate use programme, with relief of symptoms within weeks, and radiological partial response after two months of treatment. He has not experienced side effects after six months of treatment. INTERPRETATION: Precision medicine is dependent on diagnostic methods such as NGS to identify patients who might benefit from targeted therapies. Selective inhibitors of molecular oncogenic drivers are usually effective and well tolerated.


Assuntos
Neoplasias Pulmonares , Proteínas Tirosina Quinases , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Masculino , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-ret/genética , Pirazóis , Piridinas , Pirimidinas , Tirosina
5.
Environ Int ; 157: 106879, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34543936

RESUMO

The study of pesticide metabolism in crops is critical for assessing the mode of action and environmental risks of pesticides. However, the study of pesticide metabolism in crops is usually complicated and it is often a daunting challenge to accurately screen the metabolites of novel pesticides in complex matrices. This study demonstrated a combined use of high-specific activity carbon-14 labeling and high-resolution mass spectrometry (HSA-14C-HRMS) for metabolism profiling of a novel neonicotinoid cycloxaprid in rice. By generating the characteristic radioactive peaks on the liquid chromatogram, the use of 14C can eliminate the severe interference of complex matrices and quickly probe target compounds; by producing ion pairs with unique abundance ratios on HRMS, high-specific activity labeling can effectively exclude false matrix positives and promote the elucidation of metabolite structure. The structures of 15 metabolites were identified, three of which were further confirmed by authentic standards. Based on these metabolites, a metabolic profile of cycloxaprid was established, which includes denitrification, demethylation, imidazolidine hydroxylation and ring cleavage olefin formation, oxidation and carboxylation reactions. The strategy of combining high-specific activity 14C labeling and HRMS offers unique advantages and provides a powerful solution for profiling unknown metabolites of novel pesticides in complex matrices, especially when traditional non-labeling methods are not feasible.


Assuntos
Oryza , Praguicidas , Radioisótopos de Carbono , Compostos Heterocíclicos com 3 Anéis , Espectrometria de Massas , Piridinas
6.
BMC Cancer ; 21(1): 1054, 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34563169

RESUMO

BACKGROUND: Cervical cancer is the tenth diagnosed cancer in the world. Early-stage and locally recurrent disease may be cured with radical surgery or chemo-radiotherapy. However, if disease persists or recurs, options are limited and the prognosis is poor. In addition to chemotherapy, bevacizumab, an antiangiogenic agent, has recently demonstrated its efficacy in this setting. Cabozantinib is an oral small molecule tyrosine kinase inhibitor that exhibits potent inhibitory activity against several receptor tyrosine kinases that are known to influence tumor growth, metastasis, and angiogenesis. The main targets of Cabozantinib are VEGFR2, MET and AXL. It is currently approved for the treatment of metastatic renal cell carcinoma, hepatocellular carcinoma and medullary thyroid carcinoma. Given its angiogenic properties associated with growth factor receptors inhibition, Cabozantinib represents a potential active treatment in cervical carcinoma. In this context, we propose to assess the efficacy and safety of cabozantinib monotherapy in advanced/metastatic cervical carcinoma (CC) after failure to platinum-based regimen treatment. METHODS: This study is a single-arm two-stage multicenter phase II aiming to simultaneously assess efficacy and safety of Cabozantinib among advanced/metastatic cervical carcinoma (CC) after failure to platinum-based regimen treatment. The main criterion will be based on both safety and clinical efficacy by conducting a Bryant-and-Day design. Safety endpoint is the proportion of patients with clinical gastro-intestinal (GI) perforation/fistula, GI-vaginal fistula and genito-urinary (GU) fistula events grade ≥ 2 (NCI CTCAE V.5.0) occurring up to one month after the end of treatment. Efficacy endpoint is the proportion of patients with disease control rate 3 months after Cabozantinib initiation. A patients' self-reported quality of life evaluation is also planned, as well as the investigation of nutritional outcomes. Cabozantinib will be administered at the daily dose of 60 mg given orally, without interruption until disease progression or discontinuation for any cause. DISCUSSION: Cabozantinib is a promising drug for patients with advanced/metastatic cervical cancer where few therapeutics options are available after failure to platinum-based regimen metastatic CC. It appears challenging to assess the interest of Cabozantinib in this indication, taking into account the potential toxicity of the drug. TRIAL REGISTRATION: NCT04205799 , registered "2019 12 19". PROTOCOL VERSION: Version 3.1 dated from 2020 08 31.


Assuntos
Anilidas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Piridinas/uso terapêutico , Neoplasias do Colo do Útero/tratamento farmacológico , Adulto , Anilidas/efeitos adversos , Feminino , Humanos , Compostos de Platina/uso terapêutico , Inibidores de Proteínas Quinases/efeitos adversos , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Piridinas/efeitos adversos , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Falha de Tratamento , Neoplasias do Colo do Útero/patologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores
7.
Medicine (Baltimore) ; 100(38): e27013, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34559096

RESUMO

BACKGROUND: The present network meta-analysis was conducted to perform an indirect comparison among ramucirumab, regorafenib, and cabozantinib in patients with advanced hepatocellular carcinoma (HCC) progressed on sorafenib treatment. METHODS: A systematic review through Medline, Embase, and Cochrane library was developed, with eligible randomized clinical trials been included. Hazard ratios (HRs) including progression-free survival (PFS), overall survival (OS), odds ratios of disease control rate (DCR), objective response rate (ORR), and adverse events were compared indirectly with network meta-analysis using random model in software STATA version 13.0. RESULTS: A total of 4 randomized clinical trials including 2137 patients met the eligibility criteria and enrolled. Indirect comparisons showed that there was no statistical difference observed in the indirect comparison of PFS, OS, ORR, or DCR among agents of regorafenib, cabozantinib, and ramucirumab in advanced HCC patients with elevated α-fetoprotein (AFP) (400 ng/mL or higher). However, in patients with low-level AFP (lower than 400 ng/mL), regorafenib was the only agent associated with significant superiority in OS, compared with placebo (hazard ratio 0.67, 95% CI, 0.50-0.90). CONCLUSIONS: The present network meta-analysis revealed that there might be no statistical difference observed in the indirect comparison of PFS, OS, ORR, or DCR among regorafenib, cabozantinib, or ramucirumab in advanced HCC patients with elevated AFP (400 ng/mL or higher). However, in patients with low-level AFP (lower than 400 ng/mL), regorafenib might be associated with significant superiority in OS, compared to placebo, which need further investigation in clinical practice.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Anilidas/administração & dosagem , Anilidas/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Hepatocelular/secundário , Esquema de Medicação , Humanos , Neoplasias Hepáticas/patologia , Metástase Neoplásica , Compostos de Fenilureia/administração & dosagem , Compostos de Fenilureia/uso terapêutico , Piridinas/administração & dosagem , Piridinas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Sorafenibe/administração & dosagem , Sorafenibe/uso terapêutico
8.
Medicine (Baltimore) ; 100(38): e27082, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34559100

RESUMO

RATIONALE: Recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT) remains a major therapeutic challenge. In recent years, new molecular-targeted therapies, such as cabozantinib, have been approved for the treatment of advanced HCC. However, clinical experience with these new drugs in the treatment of HCC in the LT setting is very limited. PATIENT CONCERNS: In 2003, a 36-year-old woman was referred to the hospital with right upper abdominal pain. DIAGNOSIS: An initial ultrasound of the liver demonstrated a large unclear lesion of the left lobe of the liver. The magnet resonance imaging findings confirmed a multifocal inoperable HCC in a non-cirrhotic liver. Seven years after receiving a living donor LT, pulmonary and intra-hepatic recurrence of the HCC was radiologically diagnosed and histologically confirmed. INTERVENTIONS: Following an interdisciplinary therapy concept consisting of surgical, interventional-radiological (with radiofrequency ablation [RFA]) as well as systemic treatment, the patient achieved a survival of more than 10 years after tumor recurrence. As systemic first line therapy with sorafenib was accompanied by grade 3 to 4 toxicities, such as mucositis, hand-foot skin reaction, diarrhea, liver dysfunction, and hyperthyroidism, it had to be discontinued. After switching to cabozantinib from June 2018 to April 2020, partial remission of all tumor manifestations was achieved. The treatment of the remaining liver metastasis could be completed by RFA. The therapy with cabozantinib was well tolerated, only mild arterial hypertension and grade 1 to 2 mucositis were observed. Liver transplant function was stable during the therapy, no drug interaction with immunosuppressive drugs was observed. OUTCOMES: More than 10 years survival after recurrence of HCC after living-donor LT due to intensive multimodal therapy concepts, including surgery, RFA, and systemic therapy with cabozantinib in the second line therapy. LESSONS: In conclusion, this report highlights the tolerability and effectiveness of cabozantinib for the treatment of HCC recurrence after LT. We show that our patient with a late recurrence of HCC after LT benefitted from intensive multimodal therapy concepts, including surgery, RFA, and systemic therapy.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , Transplante de Fígado , Dor Abdominal/etiologia , Adulto , Anilidas/administração & dosagem , Anilidas/uso terapêutico , Carcinoma Hepatocelular/secundário , Carcinoma Hepatocelular/terapia , Terapia Combinada , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Terapia de Alvo Molecular , Metástase Neoplásica , Recidiva Local de Neoplasia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/terapia , Piridinas/administração & dosagem , Piridinas/uso terapêutico , Ablação por Radiofrequência
9.
Drugs Today (Barc) ; 57(9): 543-550, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34586102

RESUMO

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by joint inflammation and progressive disability when inflammation cannot be sufficiently controlled. Despite treatment with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) and biological DMARDs (bDMARDs), up to 30% of RA patients do not reach or fail to maintain a good response over time. The recent introduction of Janus kinase inhibitors (JAKis) has widened the rheumatologist's armamentarium. Filgotinib, a selective JAK1 inhibitor, has been approved by the European Medicines Agency (EMA) for treatment of RA. Phase II and III studies highlighted filgotinib safety and efficacy in RA patients naive to DMARDs or with inadequate response to csDMARDs and bDMARDs. Filgotinib is administered orally at 200 mg every day. For patients older than 75 years or with moderate to severe renal impairment, a dose of filgotinib 100 mg every day is recommended.


Assuntos
Antirreumáticos , Artrite Reumatoide , Antirreumáticos/efeitos adversos , Artrite Reumatoide/tratamento farmacológico , Humanos , Piridinas/uso terapêutico , Triazóis/uso terapêutico
10.
Drugs Today (Barc) ; 57(9): 559-569, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34586104

RESUMO

The identification of oncogenic drivers and the subsequent development of targeted therapies have been established as biomarker-based care for metastatic non-small cell lung cancer (NSCLC) patients. Rearranged during transfection (RET) events have been reported to be oncogenic drivers in NSCLC and were more common in patients who i) were young; ii) had adenocarcinoma histology; and iii) had never smoked. Phase II studies indicated the limited efficacy of multi-targeted tyrosine kinase inhibitors in patients with NSCLC that have a confirmed RET event. Consequently, there has been ongoing research to develop more potent and specific RET tyrosine kinase inhibitors. Recently, a novel and specific RET inhibitor, pralsetinib (BLU-667), has been reported to have excellent efficacy and low off-target toxicity in RET cancer patients. In this review, we summarize the clinical data regarding the use of pralsetinib in NSCLC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Proteínas Proto-Oncogênicas c-ret , Pirazóis , Piridinas , Pirimidinas
11.
Int J Pharm ; 608: 121122, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34560207

RESUMO

Herein, we demonstrated the development and characterization of a dry powder inhaler (DPI) formulation of edoxaban (EDX); and investigated the in-vitro anticoagulation effect for the management of pulmonary or cerebral coagulopathy associated with COVID-19 infection. The formulations were prepared by mixing the inhalable micronized drug with a large carrier lactose and dispersibility enhancers, leucine, and magnesium stearate. The drug-excipient interaction was studied using X-Ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) methods. The drug and excipients showed no physical inter particulate interaction. The in-vitro drug aerosolization from the developed formulation was determined by a Twin Stage Impinger (TSI) at a flow rate of 60 ± 5 L /min. The amount of drug deposition was quantified by an established HPLC-UV method. The fine particle fraction (FPF) of EDX API from drug alone formulation was 7%, whereas the formulations with excipients increased dramatically to almost 7-folds up to 47%. The developed DPI formulation of EDX showed a promising in-vitro anticoagulation effect at a very low concentration. This novel DPI formulation of EDX could be a potential and effective inhalation therapy for managing pulmonary venous thromboembolism (VTE) associated with COVID-19 infection. Further studies are warranted to investigate the toxicity and clinical application of the inhaled EDX DPI formulation.


Assuntos
Transtornos da Coagulação Sanguínea/tratamento farmacológico , COVID-19 , Inaladores de Pó Seco , Piridinas/administração & dosagem , Tiazóis/administração & dosagem , Administração por Inalação , Aerossóis , Transtornos da Coagulação Sanguínea/virologia , COVID-19/complicações , Humanos , Tamanho da Partícula , Pós
12.
Proc Natl Acad Sci U S A ; 118(39)2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34548397

RESUMO

Enzymes possessing the nickel-pincer nucleotide (NPN) cofactor catalyze C2 racemization or epimerization reactions of α-hydroxyacid substrates. LarB initiates synthesis of the NPN cofactor from nicotinic acid adenine dinucleotide (NaAD) by performing dual reactions: pyridinium ring C5 carboxylation and phosphoanhydride hydrolysis. Here, we show that LarB uses carbon dioxide, not bicarbonate, as the substrate for carboxylation and activates water for hydrolytic attack on the AMP-associated phosphate of C5-carboxylated-NaAD. Structural investigations show that LarB has an N-terminal domain of unique fold and a C-terminal domain homologous to aminoimidazole ribonucleotide carboxylase/mutase (PurE). Like PurE, LarB is octameric with four active sites located at subunit interfaces. The complex of LarB with NAD+, an analog of NaAD, reveals the formation of a covalent adduct between the active site Cys221 and C4 of NAD+, resulting in a boat-shaped dearomatized pyridine ring. The formation of such an intermediate with NaAD would enhance the reactivity of C5 to facilitate carboxylation. Glu180 is well positioned to abstract the C5 proton, restoring aromaticity as Cys221 is expelled. The structure of as-isolated LarB and its complexes with NAD+ and the product AMP identify additional residues potentially important for substrate binding and catalysis. In combination with these findings, the results from structure-guided mutagenesis studies lead us to propose enzymatic mechanisms for both the carboxylation and hydrolysis reactions of LarB that are distinct from that of PurE.


Assuntos
Cisteína/química , Hidrolases/metabolismo , Lactobacillus plantarum/enzimologia , Níquel/metabolismo , Nucleotídeos/biossíntese , Piridinas/química , Racemases e Epimerases/metabolismo , Carboxiliases , Catálise , Cristalografia por Raios X , Hidrolases/química , Hidrólise , Modelos Moleculares , Conformação Proteica , Racemases e Epimerases/química , Especificidade por Substrato
13.
Nat Commun ; 12(1): 5248, 2021 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-34504076

RESUMO

The HRAS, NRAS, and KRAS genes are collectively mutated in a fifth of all human cancers. These mutations render RAS GTP-bound and active, constitutively binding effector proteins to promote signaling conducive to tumorigenic growth. To further elucidate how RAS oncoproteins signal, we mined RAS interactomes for potential vulnerabilities. Here we identify EFR3A, an adapter protein for the phosphatidylinositol kinase PI4KA, to preferentially bind oncogenic KRAS. Disrupting EFR3A or PI4KA reduces phosphatidylinositol-4-phosphate, phosphatidylserine, and KRAS levels at the plasma membrane, as well as oncogenic signaling and tumorigenesis, phenotypes rescued by tethering PI4KA to the plasma membrane. Finally, we show that a selective PI4KA inhibitor augments the antineoplastic activity of the KRASG12C inhibitor sotorasib, suggesting a clinical path to exploit this pathway. In sum, we have discovered a distinct KRAS signaling axis with actionable therapeutic potential for the treatment of KRAS-mutant cancers.


Assuntos
Carcinogênese/genética , Neoplasias Pulmonares/genética , Proteínas de Membrana/genética , Antígenos de Histocompatibilidade Menor/genética , Neoplasias Pancreáticas/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Animais , Antineoplásicos/farmacologia , Carcinogênese/metabolismo , Carcinogênese/patologia , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Cães , Inibidores Enzimáticos/farmacologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Células HEK293 , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Células Madin Darby de Rim Canino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos SCID , Antígenos de Histocompatibilidade Menor/metabolismo , Mutação , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Fosfatos de Fosfatidilinositol/biossíntese , Fosfatidilserinas/biossíntese , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Piridinas/farmacologia , Pirimidinas/farmacologia , Análise de Sobrevida , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
14.
J Phys Chem Lett ; 12(37): 9020-9025, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34516127

RESUMO

Ribonucleotide reductase (RNR), which supplies the building blocks for DNA biosynthesis and its repair, has been linked to human diseases and is emerging as a therapeutic target. Here, we present a mechanistic investigation of triapine (3AP), a clinically relevant small molecule that inhibits the tyrosyl radical within the RNR ß2 subunit. Solvent kinetic isotope effects reveal that proton transfer is not rate-limiting for inhibition of Y122· of E. coli RNR ß2 by the pertinent 3AP-Fe(II) adduct. Vibrational spectroscopy further demonstrates that unlike inhibition of the ß2 tyrosyl radical by hydroxyurea, a carboxylate containing proton wire is not at play. Binding measurements reveal a low nanomolar affinity (Kd ∼ 6 nM) of 3AP-Fe(II) for ß2. Taken together, these data should prompt further development of RNR inactivators based on the triapine scaffold for therapeutic applications.


Assuntos
Inibidores Enzimáticos/química , Proteínas de Escherichia coli/metabolismo , Escherichia coli/enzimologia , Compostos Ferrosos/química , Piridinas/química , Ribonucleotídeo Redutases/metabolismo , Tiossemicarbazonas/química , Inibidores Enzimáticos/metabolismo , Proteínas de Escherichia coli/antagonistas & inibidores , Radicais Livres/química , Radicais Livres/metabolismo , Hidroxiureia/química , Ligação Proteica , Subunidades Proteicas/antagonistas & inibidores , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo , Ribonucleotídeo Redutases/antagonistas & inibidores , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Behav Neurol ; 2021: 9536054, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34539935

RESUMO

Background: The purpose of this meta-analysis was to assess the clinical efficacy of etoricoxib in comparison with traditional NSAIDs for postoperative pain after third molar surgery. Methods: The quality of studies found in PubMed and Google Scholar was evaluated with Cochrane Collaboration's risk of bias tool. Data on total consumption of rescue analgesics, number of patients using rescue analgesics, global assessment of study treatments, and adverse effects were extracted exclusively from high-quality clinical trials. Each meta-analysis was performed with the Review Manager Software 5.3 for Windows. Results: The qualitative analysis showed that etoricoxib has better analgesic activity when compared with ibuprofen (2 clinical trials) and diclofenac (1 clinical trial). A similar analgesic efficacy between etoricoxib and nonselective Cox-2 NSAIDs was informed in 3/8 studies (2 compared to ibuprofen and 1 to naproxen sodium). Moreover, the number of patients requiring rescue analgesics in the postoperative period showed a statistical difference in favor of etoricoxib when compared to NSAIDs. Conclusion: Etoricoxib significantly reduces the number of patients needing rescue analgesics compared to NSAIDs after third molar surgery.


Assuntos
Dente Serotino , Sulfonas , Analgésicos , Etoricoxib , Humanos , Dente Serotino/cirurgia , Piridinas/uso terapêutico , Sulfonas/uso terapêutico
16.
Nat Commun ; 12(1): 5305, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34489447

RESUMO

Mitochondrial dysfunction is a common hallmark of neurological disorders, and reducing mitochondrial damage is considered a promising neuroprotective therapeutic strategy. Here, we used high-throughput small molecule screening to identify CHIR99021 as a potent enhancer of mitochondrial function. CHIR99021 improved mitochondrial phenotypes and enhanced cell viability in several models of Huntington's disease (HD), a fatal inherited neurodegenerative disorder. Notably, CHIR99201 treatment reduced HD-associated neuropathology and behavioral defects in HD mice and improved mitochondrial function and cell survival in HD patient-derived neurons. Independent of its known inhibitory activity against glycogen synthase kinase 3 (GSK3), CHIR99021 treatment in HD models suppressed the proteasomal degradation of calpastatin (CAST), and subsequently inhibited calpain activation, a well-established effector of neural death, and Drp1, a driver of mitochondrial fragmentation. Our results established CAST-Drp1 as a druggable signaling axis in HD pathogenesis and highlighted CHIR99021 as a mitochondrial function enhancer and a potential lead for developing HD therapies.


Assuntos
Proteínas de Ligação ao Cálcio/genética , Dinaminas/genética , Doença de Huntington/genética , Mitocôndrias/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Piridinas/farmacologia , Pirimidinas/farmacologia , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Calpaína/genética , Calpaína/metabolismo , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Modelos Animais de Doenças , Dinaminas/metabolismo , Regulação da Expressão Gênica , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Doença de Huntington/tratamento farmacológico , Doença de Huntington/metabolismo , Doença de Huntington/patologia , Injeções Intraperitoneais , Masculino , Camundongos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Cultura Primária de Células , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Transdução de Sinais
17.
J Pharm Biomed Anal ; 205: 114343, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34500236

RESUMO

Cabozantinib is a potent inhibitor of tyrosine kinase receptor that plays key role in tumor pathogenesis. Cabozantinib has been approved by U. S. Food and Drug Administration for the treatment of cancer. The present work was aimed to explore the in vitro metabolism of cabozantinib using liver microsomes and hepatocytes from animal species and humans through ultra-high performance liquid chromatography coupled to quadrupole/orbitrap high resolution mass spectrometer. The metabolites were characterized by their elemental compositions, MS and MS/MS spectra. As a result, a total of 26 metabolites were identified, and 15 metabolites were newly reported. Among these metabolites, M12 (oxidative defluorination), M19 and M22 (demethylation), M21 (hydroxylation) and M26 (N-oxygenation) were the major metabolites in all species. Our data revealed that cabozantinib was metabolized via the following pathways: oxidative defluorination, hydroxylation, amide hydrolysis, O-dealkylation, N-oxygenation, demethylation and glucuronidation. Human recombinant cytochrome P450 (CYP) enzyme analysis revealed that metabolism of cabozantinib was mainly catalyzed by CYP3A4, while other CYP enzymes played negligible role. The current study provided valuable metabolic data of cabozantinib from different animal species and humans, which would aid in safety and efficacy assessment.


Assuntos
Microssomos Hepáticos , Espectrometria de Massas em Tandem , Anilidas , Animais , Cromatografia Líquida de Alta Pressão , Hepatócitos , Humanos , Piridinas , Estados Unidos
18.
Ecotoxicol Environ Saf ; 225: 112700, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34500385

RESUMO

Forchlorfenuron is a widely used plant growth regulator. The uptake of forchlorfenuron and its major metabolites poses a potential risk for human health. However, little is known about the dissipation of forchlorfenuron and its major metabolites in agricultural food. In this study, the metabolite 4-hydroxyphenyl-forchlorfenuron was first identified in oriental melon, which exhibited the highest level of residues of 4.42-5.12 µg/kg on the 4-7th days after application. Forchlorfenuron was found to be dissipated rapidly in melon at the recommended application rates, with half-lives ranging from 1.20 to 1.33 days. The rate of dissipation of 4-hydroxyphenyl-forchlorfenuron was greater than that of metabolism from forchlorfenuron in the oriental melon. However, the other metabolite, 3-hydroxyphenyl-forchlorfenuron, was not detected in oriental melon. The risk assessment showed that the acute and chronic dietary exposure risks of forchlorfenuron in oriental melon were 0.0011-0.0037% and 0.06-0.12%, respectively, suggesting little health risk to Chinese consumers.


Assuntos
Cucumis melo , Compostos de Fenilureia , Humanos , Compostos de Fenilureia/toxicidade , Piridinas/toxicidade , Medição de Risco
19.
Ecotoxicol Environ Saf ; 225: 112766, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34509967

RESUMO

Natural adjuvants are novel options to reduce the doses of chemical herbicides. The aim of the current study was to examine the compositions and adjuvant effects of rosin and coconut oil on herbicides using a combination of indoor experiment and field trial. The GC-MS results showed that the main component of rosin was abietic acid (40.02%), and the main components of coconut oil were 2-pentanone, 4-hydroxy-4-methyl- (21.45%) and dodecanoic acid (14.59%). In greenhouse experiment, rosin showed a significant adjuvant effect on nicosulfuron against Digitaria sanguinalis and Amaranthus retroflexus, with the GR50 ratios of 1.47 and 1.69, respectively. The GR50 values of nicosulfuron in the present of coconut oil were 3.99 and 10.13 g a.i./hm2 against D. sanguinalis and A. retroflexus, lower than that of individual application. The adjuvant effect of rosin and coconut oil on mesotrione was also found. In field trial, the fresh weight control efficiency of nicosulfuron (45 g a.i./hm2) and mesotrione (112.5 g a.i./hm2) was significantly improved after the addition of rosin and coconut oil, similar with that of recommended dose. Rosin and coconut oil could reduce the contact angle of nicosulfuron, with the results of 56.68° and 53.90°, respectively, lower than that of individual application. Furthermore, rosin and coconut oil could decrease the surface tension, wetting and penetration time; and increase the spreading diameter and maximum retention. Both rosin and coconut oil have adjuvant effects on herbicides in the lab & field with multiple mechanisms. Thus, they have the potential to be developed into natural adjuvants for herbicide formulation to control weeds.


Assuntos
Adjuvantes Farmacêuticos , Óleo de Coco , Cicloexanonas , Piridinas , Resinas Vegetais , Compostos de Sulfonilureia
20.
Ann Palliat Med ; 10(9): 9902-9913, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34551570

RESUMO

BACKGROUND: Apatinib in combination with chemotherapy (CT) has been used in the treatment of ovarian cancer (OC), however, the safety and efficacy are unclear. The study aims at systematic evaluation of the safety and efficacy of the apatinib targeted therapy in combination with CT for the treatment of patients with advanced OC. METHODS: Literature about randomized controlled clinical trials was searched using search engines such as PubMed, EMBASE, Web of Science, CNKI, the Cochrane Library, CBM, VIP and the Wanfang. We collected the related clinical studies of apatinib in combination with CT in the treatment of OC. The duration of the data retrieval related to clinical studies was from the database establishment to September 2020. Adverse reactions (ADRs) due to treatment, disease control rate (DCR), and that of objective response rate (ORR), were collected as indicators to show treatment outcomes. The literature was independently screened by two researchers. They extracted the data and evaluated the risk of biases of the included studies. Then, Revman 5.4 software was employed for performing the meta-analysis. RESULTS: Twelve randomized controlled clinical trials with 698 patients having an advanced stage of OC were included. The results revealed that in comparison with the treatment with only CT, apatinib targeted therapy combination with CT showed significant improvement in the patients' ORR [OR =3.19, 95% CI: (2.06, 4.94), P<0.00001] and DCR [OR =4.97, 95% CI: (2.90, 8.52), P<0.00001]. The group that was treated with a combined therapy had shown proteinuria in higher amount (OR =3.08, 95% CI: 51.13-8.42, P<0.00001), while the analyses of other ADRs, such nausea and vomiting (OR =1.10, 95% CI: 0.67-1.79, P=0.71), hand-foot syndrome (OR =1.73, 95% CI: 0.97-3.10, P=0.06), hypertension (OR =1.18, 95% CI: 0.73-1.91, P=0.0.51), diarrhea (OR =1.05, 95% CI: 0.56-1.97, P=0.87), leucopenia (OR =1.22, 95% CI: 0.70-2.12, P=0.48), and myelosuppression (OR =1.00, 95% CI: 0.28-3.62, P=1.00), did not show any significant difference (P>0.05). DISCUSSION: The effects of apatinib combination with CT for the treatment of OC are significantly better than the CT used alone in ORR and DCR, despite with a relative low incidence of adverse effects. However, due to the very low number of studies available, the results need to be further verified using a high-quality, large sample and long-term studies.


Assuntos
Neoplasias Ovarianas , Piridinas , Feminino , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Piridinas/efeitos adversos , Resultado do Tratamento
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