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1.
Int J Nanomedicine ; 16: 1-14, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33442247

RESUMO

Introduction: The present study reports on examination of the effects of encapsulating the tyrosine kinase inhibitors (TKIs) vandetanib and lenvatinib into a biomacromolecular ferritin-based delivery system. Methods: The encapsulation of TKIs was performed via two strategies: i) using an active reversible pH-dependent reassembly of ferritin´s quaternary structure and ii) passive loading of hydrophobic TKIs through the hydrophobic channels at the junctions of ferritin subunits. After encapsulation, ferritins were surface-functionalized with folic acid promoting active-targeting capabilities. Results: The physico-chemical and nanomechanical analyses revealed that despite the comparable encapsulation efficiencies of both protocols, the active loading affects stability and rigidity of ferritins, plausibly due to their imperfect reassembly. Biological experiments with hormone-responsive breast cancer cells (T47-D and MCF-7) confirmed the cytotoxicity of encapsulated and folate-targeted TKIs to folate-receptor positive cancer cells, but only limited cytotoxic effects to healthy breast epithelium. Importantly, the long-term cytotoxic experiments revealed that compared to the pH-dependent encapsulation, the passively-loaded TKIs exert markedly higher anticancer activity, most likely due to undesired influence of harsh acidic environment used for the pH-dependent encapsulation on the TKIs' structural and functional properties. Conclusion: Since the passive loading does not require a reassembly step for which acids are needed, the presented investigation serves as a solid basis for future studies focused on encapsulation of small hydrophobic molecules.


Assuntos
Sistemas de Liberação de Medicamentos , Ferritinas/química , Ácido Fólico/química , Compostos de Fenilureia/farmacologia , Piperidinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/farmacologia , Quinolinas/farmacologia , Animais , Antineoplásicos/farmacologia , Materiais Biocompatíveis/química , Morte Celular/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Células Clonais , Difusão , Portadores de Fármacos/química , Cavalos , Humanos , Concentração de Íons de Hidrogênio , Compostos de Fenilureia/química , Piperidinas/química , Quinazolinas/química , Quinolinas/química , Propriedades de Superfície
2.
Biochim Biophys Acta Gen Subj ; 1865(1): 129773, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33132199

RESUMO

BACKGROUND: Quinazolines 1 to 6, with an aromatic or aryl-vinyl substituent in position 2 are selected with the aim to compare their structures and biological activity. The selection includes a natural alkaloid, schizocommunin, and the synthetic 2-(2'-quinolyl)-3H-quinazolin-4-one, known to interact with guanine-quadruplex dependent enzymes, respectively telomerase and topoisomerase. METHODS: Breast cancer cells of the MDA cell line have been used to study the bioactivity of the tested compounds by the method of Comet Assay and FACS analyses. We model observed effects assuming stacking interactions of studied heterocycles with a naked skeleton of G-quadruplex, consisting of guanine quartet layers and potassium ions. Interaction energies are computed using a dispersion corrected density functional theory method, and an electron-correlated molecular orbital theory method. RESULTS: Selected compounds do not remarkably delay nor change the dynamics of cellular progression through the cell cycle phases, while changing significantly cell morphology. Our computational models quantify structural effects on heterocyclic G4-complex stabilization energies, which directly correlate with observed biological activity. CONCLUSION: Our computational model of G-quadruplexes is an acceptable tool for the study of interaction energies of G-quadruplexes and heterocyclic ligands, predicting, and allowing design of novel structures. GENERAL SIGNIFICANCE: Genotoxicity of quinazolin-4-one analogues on human breast cancer cells is not related to molecular metabolism but rather to their interference with G-quadruplex regulatory mechanisms. Computed stabilization energies of heterocyclic ligand complexes of G-quadruplexes might be useful in the prediction of novel telomerase / helicase, topoisomerase and NA polymerase dependent drugs.


Assuntos
Quadruplex G/efeitos dos fármacos , Quinazolinas/química , Quinazolinas/farmacologia , Linhagem Celular Tumoral , Desenho de Fármacos , Descoberta de Drogas , Humanos , Indóis/química , Indóis/farmacologia , Modelos Moleculares , Quinazolinonas/química , Quinazolinonas/farmacologia , Telômero/química
3.
J Med Chem ; 63(24): 15906-15945, 2020 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-33314925

RESUMO

HER2 kinase as a well-established target for breast cancer (BC) therapy is associated with aggressive clinical outcomes; thus, herein we present structural optimization for HER2-selective targeting. HER2 profiling of the developed derivatives demonstrated potent and selective inhibitions (IC50: 5.4-12 nM) compared to lapatinib (IC50: 95.5 nM). Favorably, 17d exhibited minimum off-target kinase activation. NCI-5-dose screening revealed broad-spectrum activities (GI50: 1.43-2.09 µM) and 17d had a remarkable selectivity toward BC. Our compounds revealed significant selective and potent antiproliferative activities (∼20-fold) against HER2+ (AU565, BT474) compared to HER2(-) cells. At 0.1 IC50, 15i, 17d, and 25b inhibited pERK1/2 and pAkt by immunoblotting. Furthermore, 17d demonstrated potent in vivo tumor regression against the BT474 xenograft model. Notably, a metastasis case was observed in the vehicle but not in the test mice groups. CD-1 mice metabolic stability assay revealed high stability and low intrinsic clearance of 17d (T1/2 > 145 min and CLint(mic) < 9.6 mL/min/kg).


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Desenho de Fármacos , Lapatinib/química , Terapia de Alvo Molecular , Quinazolinas/síntese química , Quinazolinas/farmacologia , Receptor ErbB-2/antagonistas & inibidores , Animais , Apoptose , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Técnicas In Vitro , Camundongos , Camundongos Nus , Receptor ErbB-2/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
5.
PLoS One ; 15(8): e0237976, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32822399

RESUMO

Environmental exposure to arsenite (As3+) has a strong association with the development of human urothelial cancer (UC) and is the 5th most common cancer in men and the 12th most common cancer in women. Muscle invasive urothelial cancer (MIUC) are grouped into basal or luminal molecular subtypes based on their gene expression profile. The basal subtype is more aggressive and can be associated with squamous differentiation, characterized by high expression of keratins (KRT1, 5, 6, 14, and 16) and epidermal growth factor receptor (EGFR) within the tumors. The luminal subtype is less aggressive and is predominately characterized by elevated gene expression of peroxisome proliferator-activated receptor- gamma (PPARγ) and forkhead box protein A1 (FOXA1). We have previously shown that As3+-transformed urothelial cells (As-T) exhibit a basal subtype of UC expressing genes associated with squamous differentiation. We hypothesized that the molecular subtype of the As-T cells could be altered by inducing the expression of PPARγ and/or inhibiting the proliferation of the cells. Non-transformed and As-T cells were treated with Troglitazone (TG, PPARG agonist, 10 µM), PD153035 (PD, an EGFR inhibitor, 1 µM) or a combination of TG and PD for 3 days. The results obtained demonstrate that treatment of the As-T cells with TG upregulated the expression of PPARγ and FOXA1 whereas treatment with PD decreased the expression of some of the basal keratins. However, a combined treatment of TG and PD resulted in a consistent decrease of several proteins associated with the basal subtype of bladder cancers (KRT1, KRT14, KRT16, P63, and TFAP2A). Our data suggests that activation of PPARγ while inhibiting cell proliferation facilitates the regulation of genes involved in maintaining the luminal subtype of UC. In vivo animal studies are needed to address the efficacy of using PPARγ agonists and/or proliferation inhibitors to reduce tumor grade/stage of MIUC.


Assuntos
Arsenitos/farmacologia , Proliferação de Células/efeitos dos fármacos , PPAR gama/metabolismo , Troglitazona/farmacologia , Animais , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Fator 3-alfa Nuclear de Hepatócito/genética , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Humanos , Queratinas/genética , Queratinas/metabolismo , Camundongos , Camundongos Nus , PPAR gama/agonistas , Quinazolinas/farmacologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma/efeitos dos fármacos , Transplante Heterólogo , Regulação para Cima/efeitos dos fármacos , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia
6.
Bioorg Med Chem Lett ; 30(20): 127472, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32781216

RESUMO

New therapies for treating coronaviruses are urgently needed. A series of 4-anilino-6-aminoquinazoline derivatives were synthesized and evaluated to show high anti-MERS-CoV activities. N4-(3-Chloro-4-fluorophenyl)-N6-(3-methoxybenzyl)quinazoline-4,6-diamine (1) has been identified in a random screen as a hit compound for inhibiting MERS-CoV infection. Throughout optimization process, compound 20 was found to exhibit high inhibitory effect (IC50 = 0.157 µM, SI = 25) with no cytotoxicity and moderate in vivo PK properties.


Assuntos
Compostos de Anilina/farmacologia , Antivirais/farmacologia , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Quinazolinas/farmacologia , Compostos de Anilina/síntese química , Compostos de Anilina/farmacocinética , Compostos de Anilina/toxicidade , Animais , Antivirais/síntese química , Antivirais/farmacocinética , Antivirais/toxicidade , Linhagem Celular , Chlorocebus aethiops , Cricetulus , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Quinazolinas/síntese química , Quinazolinas/farmacocinética , Quinazolinas/toxicidade , Ratos , Relação Estrutura-Atividade
7.
Molecules ; 25(17)2020 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-32842606

RESUMO

Presently, there are no approved drugs or vaccines to treat COVID-19, which has spread to over 200 countries and at the time of writing was responsible for over 650,000 deaths worldwide. Recent studies have shown that two human proteases, TMPRSS2 and cathepsin L, play a key role in host cell entry of SARS-CoV-2. Importantly, inhibitors of these proteases were shown to block SARS-CoV-2 infection. Here, we perform virtual screening of 14,011 phytochemicals produced by Indian medicinal plants to identify natural product inhibitors of TMPRSS2 and cathepsin L. AutoDock Vina was used to perform molecular docking of phytochemicals against TMPRSS2 and cathepsin L. Potential phytochemical inhibitors were filtered by comparing their docked binding energies with those of known inhibitors of TMPRSS2 and cathepsin L. Further, the ligand binding site residues and non-covalent interactions between protein and ligand were used as an additional filter to identify phytochemical inhibitors that either bind to or form interactions with residues important for the specificity of the target proteases. This led to the identification of 96 inhibitors of TMPRSS2 and 9 inhibitors of cathepsin L among phytochemicals of Indian medicinal plants. Further, we have performed molecular dynamics (MD) simulations to analyze the stability of the protein-ligand complexes for the three top inhibitors of TMPRSS2 namely, qingdainone, edgeworoside C and adlumidine, and of cathepsin L namely, ararobinol, (+)-oxoturkiyenine and 3α,17α-cinchophylline. Interestingly, several herbal sources of identified phytochemical inhibitors have antiviral or anti-inflammatory use in traditional medicine. Further in vitro and in vivo testing is needed before clinical trials of the promising phytochemical inhibitors identified here.


Assuntos
Antivirais/química , Betacoronavirus/efeitos dos fármacos , Catepsina L/química , Compostos Fitoquímicos/química , Inibidores de Proteases/química , Receptores Virais/química , Serina Endopeptidases/química , Sequência de Aminoácidos , Antivirais/isolamento & purificação , Antivirais/farmacologia , Betacoronavirus/patogenicidade , Sítios de Ligação , Catepsina L/antagonistas & inibidores , Catepsina L/genética , Catepsina L/metabolismo , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/enzimologia , Infecções por Coronavirus/virologia , Cumarínicos/química , Cumarínicos/isolamento & purificação , Cumarínicos/farmacologia , Expressão Gênica , Ensaios de Triagem em Larga Escala , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Interações Hospedeiro-Patógeno/genética , Humanos , Índia , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Monossacarídeos/química , Monossacarídeos/isolamento & purificação , Monossacarídeos/farmacologia , Pandemias , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Plantas Medicinais/química , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/enzimologia , Pneumonia Viral/virologia , Inibidores de Proteases/isolamento & purificação , Inibidores de Proteases/farmacologia , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Quinazolinas/química , Quinazolinas/isolamento & purificação , Quinazolinas/farmacologia , Receptores Virais/antagonistas & inibidores , Receptores Virais/genética , Receptores Virais/metabolismo , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Termodinâmica , Internalização do Vírus/efeitos dos fármacos
8.
Asia Pac J Clin Oncol ; 16(5): e192-e197, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32506805

RESUMO

AIM: To provide guidance for appropriate imaging examinations for diagnosing spinal tumors or tumor-like lesions. METHODS: A total of 121 patients with suspected spinal tumors were included this retrospective study. Each patient underwent ≥2 imaging examinations, including computerized tomography (CT), magnetic resonance (MR), and/or emission computed tomography (ECT). All patients were diagnosed by pathology after core needle or surgical biopsies. The results were compared with those of pathological examinations using paired chi-squared tests, and compared with each other. Statistical indicators that tested the consistency of the results included McNemar's and kappa coefficients, as well as receiver operating characteristic curves. RESULTS: The differences among MR, CT, ECT, and pathology were not significant. The kappa coefficient of MR, CT, and ECT was 46.1%, 36.0%, and 55.9%, respectively. The area under the curve of ECT, MR, and CT scans was 0.809, 0.705, and 0.704, respectively; and the differences among them were significant (P < .05). Post hoc multiple comparisons showed no significant differences among imaging examinations in terms of sensitivity, specificity, misdiagnosis rate, and coincidence rate (P > .05). However, significant differences were noted in the kappa coefficient and missed diagnosis rate (P < .05). CONCLUSIONS: Although ECT was the most accurate imaging method, its high cost and large radiation dosage limit its widespread application. Furthermore, MR verified spinal tumors more effectively; however, CT excluded them more efficiently. In summary, when all factors are considered, MR is still the optimal modality for the diagnosis of spinal tumors, especially during the initial screening.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Imagem por Ressonância Magnética/métodos , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Diferenciação Celular , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Epirubicina/farmacologia , Epirubicina/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Quinazolinas/farmacologia , Quinazolinas/uso terapêutico , Estudos Retrospectivos , Tiofenos/farmacologia , Tiofenos/uso terapêutico , Adulto Jovem
9.
Sci Rep ; 10(1): 8867, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483262

RESUMO

Merkel cell carcinoma (MCC) is a highly aggressive neuroendocrine skin cancer with steadily increasing incidence and poor prognosis. Despite recent success with immunotherapy, 50% of patients still succumb to their diseases. To date, there is no Food and Drug Administration-approved targeted therapy for advanced MCC. Aberrant activation of phosphatidylinositide-3-kinase (PI3K)/AKT/mTOR pathway is frequently detected in MCC, making it an attractive therapeutic target. We previously found PI3K pathway activation in human MCC cell lines and tumors and demonstrated complete clinical response in a Stage IV MCC patient treated with PI3K inhibitor idelalisib. Here, we found that both PI3K-α and -δ isoforms are abundantly expressed in our MCC cell lines and clinical samples; we therefore examined antitumor efficacy across a panel of five PI3K inhibitors with distinctive isoform-specificities, including idelalisib (PI3K-δ), copanlisib (PI3K-α/δ), duvelisib (PI3K-γ/δ), alpelisib (PI3K-α), and AZD8186 (PI3K-ß/δ). Of these, copanlisib exerts the most potent antitumor effects, markedly inhibiting cell proliferation, survival, and tumor growth by suppressing PI3K/mTOR/Akt activities in mouse models generated from MCC cell xenografts and patient-derived tumor xenografts. These results provide compelling preclinical evidence for application of copanlisib in advanced MCC with aberrant PI3K activation for which immunotherapy is insufficient, or patients who are unsuitable for immunotherapy.


Assuntos
Carcinoma de Célula de Merkel/tratamento farmacológico , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/uso terapêutico , Pirimidinas/uso terapêutico , Quinazolinas/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Carcinoma de Célula de Merkel/metabolismo , Carcinoma de Célula de Merkel/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Fosfatidilinositol 3-Quinases/química , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirimidinas/farmacologia , Quinazolinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Transplante Heterólogo
10.
Ann Hematol ; 99(9): 2027-2036, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32567028

RESUMO

Increased expression of fetal hemoglobin (HbF) improves the clinical severity of ß-thalassemia patients. EHMT1/2 histone methyltransferases are epigenetic modifying enzymes that are responsible for catalyzing addition of the repressive histone mark H3K9me2 at silenced genes, including the γ-globin genes. UNC0638, a chemical inhibitor of EHMT1/2, has been shown to induce HbF expression in human erythroid progenitor cell cultures. Here, we report the HbF-inducing activity of UNC0638 in erythroid progenitor cells from ß-thalassemia/HbE patients. UNC0638 treatment led to significant increases in γ-globin mRNA, HbF expression, and HbF-containing cells in the absence of significant cytotoxicity. Moreover, UNC0638 showed additive effects on HbF induction in combination with the immunomodulatory drug pomalidomide and the DNMT1 inhibitor decitabine. These studies provide a scientific proof of concept that a small molecule targeting EHMT1/2 epigenetic enzymes, used alone or in combination with pomalidomide or decitabine, is a potential therapeutic approach for HbF induction. Further development of structural analogs of UNC0638 with similar biological effects but improved pharmacokinetic properties may lead to promising therapies and possible clinical application for the treatment of ß-thalassemia.


Assuntos
Células Precursoras Eritroides/metabolismo , Hemoglobina Fetal/biossíntese , Hemoglobina E/metabolismo , Quinazolinas/farmacologia , Talassemia beta/metabolismo , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Células Precursoras Eritroides/efeitos dos fármacos , Hemoglobina Fetal/genética , Expressão Gênica , Humanos , Talassemia beta/genética
11.
J Pharmacol Sci ; 143(4): 307-314, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32536591

RESUMO

Rutaecarpine, an indolopyridoquinazoline alkaloid, attracted attentions because of possessing various biological activities. The objective of this study was to investigate the effect of rutaecarpine on glucose and lipid metabolism in high fat diet-multiple low dose streptozotocin induced type 2 diabetic (HFD-db) mice and to understand the mechanism of action. HFD-db mice showed impaired glucose metabolism and lipid profile. Oral administration of rutaecarpine reduced the blood glucose levels, decreased blood hemoglobin A1c (HbA1c) levels, improved glucose tolerance and restored insulin sensitivity in HFD-db mice. Rutaecarpine also decreased body weight gain, water intake and visceral fat gain in HFD-db mice. Total cholesterol, triglycerides, very low density lipoprotein and low density lipoprotein were reduced and high density lipoprotein level was augmented in rutaecarpine treated HFD-db mice. Rutaecarpine also reduced the elevated levels of serum glutamic oxaloacetic transaminase, serum glutamic pyruvic transaminase, urea and creatinine in HFD-db mice. Rutaecarpine significantly promoted the rate of glucose consumption, glucose uptake and glycolysis in C2C12 myotubes. Western blotting results showed that rutaecarpine augmented p-GSK-3ß and p-AMPK expression, and suppressed G6Pase expression in HepG2 cells. These results suggest that rutaecarpine might be having therapeutic importance to fight against type 2 diabetes mellitus associated with dyslipidemia.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Dieta Hiperlipídica/efeitos adversos , Glucose/metabolismo , Homeostase/efeitos dos fármacos , Hipoglicemiantes , Alcaloides Indólicos/farmacologia , Fígado/metabolismo , Quinazolinas/farmacologia , Animais , Diabetes Mellitus Experimental/etiologia , Diabetes Mellitus Tipo 2/etiologia , Modelos Animais de Doenças , Alcaloides Indólicos/uso terapêutico , Masculino , Camundongos Endogâmicos C57BL , Quinazolinas/uso terapêutico
12.
Cancer Sci ; 111(7): 2431-2439, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32415892

RESUMO

MYCN gene amplification is consistently associated with poor prognosis in patients with neuroblastoma, a pediatric tumor arising from the sympathetic nervous system. Conventional anticancer drugs, such as alkylating agents and platinum compounds, have been used for the treatment of high-risk patients with MYCN-amplified neuroblastoma, whereas molecule-targeting drugs have not yet been approved. Therefore, the development of a safe and effective therapeutic approach is highly desired. Although thymidylate synthase inhibitors are widely used for colorectal and gastric cancers, their usefulness in neuroblastoma has not been well studied. Here, we investigated the efficacies of approved antifolates, methotrexate, pemetrexed, and raltitrexed (RTX), on MYCN-amplified and nonamplified neuroblastoma cell lines. Cell growth-inhibitory assay revealed that RTX showed a superior inhibitory activity against MYCN-amplified cell lines. We found no significant differences in the protein expression levels of the antifolate transporter or thymidylate synthase, a primary target of RTX, among the cell lines. Because thymidine supplementation could rescue the RTX-induced cell growth suppression, the effect of RTX was mainly due to the reduction in dTTP synthesis. Interestingly, RTX treatments induced single-stranded DNA damage response in MYCN-amplified cells to a greater extent than in the nonamplified cells. We propose that the high DNA replication stress and elevated levels of DNA damage, which are a result of deregulated expression of MYCN target genes, could be the cause of increased sensitivity to RTX.


Assuntos
Dano ao DNA , Amplificação de Genes , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/genética , Quinazolinas/farmacologia , Tiofenos/farmacologia , Timidilato Sintase/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células , Relação Dose-Resposta a Droga , Humanos , Redes e Vias Metabólicas , Neuroblastoma/metabolismo
13.
PLoS One ; 15(4): e0232140, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32353010

RESUMO

BACKGROUND: Congenital cytomegalovirus infection can lead to severe sequelae. When fetal infection is confirmed, we hypothesize that fetal treatment could improve the outcome. Maternal oral administration of an effective drug crossing the placenta could allow fetal treatment. Letermovir (LMV) and Maribavir (MBV) are new CMV antivirals, and potential candidates for fetal treatment. METHODS: The objective was to investigate the placental transfer of LMV and MBV in the ex vivo method of the human perfused cotyledon. Term placentas were perfused, in an open-circuit model, with LMV or MBV at concentrations in the range of clinical peak plasma concentrations. Concentrations were measured using ultraperformance liquid chromatography coupled with tandem mass spectrometry. Mean fetal transfer rate (FTR) (fetal (FC) /maternal concentration), clearance index (CLI), accumulation index (AI) (retention of each drug in the cotyledon tissue) were measured. Mean FC were compared with half maximal effective concentrations of the drugs (EC50(LMV) and EC50(MBV)). RESULTS: For LMV, the mean FC was (± standard deviation) 1.1 ± 0.2 mg/L, 1,000-fold above the EC50(LMV). Mean FTR, CLI and AI were 9 ± 1%, 35 ± 6% and 4 ± 2% respectively. For MBV, the mean FC was 1.4 ± 0.2 mg/L, 28-fold above the EC50(MBV). Mean FTR, CLI and AI were 10 ± 1%, 50 ± 7% and 2 ± 1% respectively. CONCLUSIONS: Drugs' concentrations in the fetal side should be in the range for in utero treatment of fetuses infected with CMV as the mean FC was superior to the EC50 for both molecules.


Assuntos
Infecções por Citomegalovirus/tratamento farmacológico , Troca Materno-Fetal/efeitos dos fármacos , Placenta/efeitos dos fármacos , Acetatos/farmacologia , Adulto , Antivirais/farmacologia , Benzimidazóis/farmacologia , Cromatografia Líquida/métodos , Feminino , Humanos , Cinética , Modelos Biológicos , Perfusão , Gravidez , Quinazolinas/farmacologia , Ribonucleosídeos/farmacologia , Espectrometria de Massas em Tandem/métodos
14.
PLoS One ; 15(5): e0233720, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32459817

RESUMO

Since patients with medullary thyroid cancer (MTC) often have metastatic disease at the time of diagnosis, the development of efficient systemic treatment options for MTC is important. Vandetanib and cabozantinib are two tyrosine kinase inhibitors (TKIs) that were recently approved by FDA and EMA for systemic treatment of metastatic MTC. Additionally, since MTC is of a neuroendocrine tumour type, treatment with radiolabelled somatostatin analogues (e.g. 177Lu-octreotate) is a valid option for patients with MTC. The aim of this study was to investigate the potentially increased therapeutic effect of combining radiation therapy with these TKIs for treatment of MTC in a mouse model. Nude mice carrying patient-derived MTC tumours (GOT2) were treated with external beam radiotherapy (EBRT) and/or one of the two TKIs vandetanib or cabozantinib. The tumour volume was determined and compared with that of mock-treated controls. The treatment doses were chosen to give a moderate effect as monotherapy to be able to detect any increased therapeutic effect from the combination therapy. At the end of follow-up, tumours were processed for immunohistochemical (IHC) analyses. The animals in the combination therapy groups showed the largest reduction in tumour volume and the longest time to tumour progression. Two weeks after start of treatment, the tumour volume for these mice was reduced by about 70-75% compared with controls. Furthermore, also EBRT and TKI monotherapy resulted in a clear anti-tumour effect with a reduced tumour growth compared with controls. The results show that an increased therapeutic effect could be achieved when irradiation is combined with TKIs for treatment of MTC. Future studies should evaluate the potential of using 177Lu-octreotate therapy in combination with TKIs in patients.


Assuntos
Anilidas/farmacologia , Carcinoma Neuroendócrino/terapia , Quimiorradioterapia , Proteínas de Neoplasias/antagonistas & inibidores , Piperidinas/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Piridinas/farmacologia , Quinazolinas/farmacologia , Neoplasias da Glândula Tireoide/terapia , Animais , Carcinoma Neuroendócrino/enzimologia , Carcinoma Neuroendócrino/patologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas de Neoplasias/metabolismo , Proteínas Tirosina Quinases/metabolismo , Neoplasias da Glândula Tireoide/enzimologia , Neoplasias da Glândula Tireoide/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
15.
PLoS One ; 15(4): e0228350, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32320391

RESUMO

Dosimetry is an important tool for triage and treatment planning following any radiation exposure accident, and biological dosimetry, which estimates exposure dose using a biological parameter, is a practical means of determining the specific dose an individual receives. The cytokinesis-blocked micronucleus assay (CBMN) is an established biodosimetric tool to measure chromosomal damage in mitogen-stimulated human lymphocytes. The CBMN method is especially valuable for biodosimetry in triage situations thanks to simplicity in scoring and adaptability to high-throughput automated sample processing systems. While this technique produces dose-response data which fit very well to a linear-quadratic model for exposures to low linear energy transfer (LET) radiation and for doses up for 5 Gy, limitations to the accuracy of this method arise at larger doses. Accuracy at higher doses is limited by the number of cells reaching mitosis. Whereas it would be expected that the yield of micronuclei increases with the dose, in many experiments it has been shown to actually decrease when normalized over the total number of cells. This variation from a monotonically increasing dose response poses a limitation for retrospective dose reconstruction. In this study we modified the standard CBMN assay to increase its accuracy following exposures to higher doses of photons or a mixed neutron-photon beam. The assay is modified either through inhibitions of the G2/M and spindle checkpoints with the addition of caffeine and/or ZM447439 (an Aurora kinase inhibitor), respectively to the blood cultures at select times during the assay. Our results showed that caffeine addition improved assay performance for photon up to 10 Gy. This was achieved by extending the assay time from the typical 70 h to just 74 h. Compared to micronuclei yields without inhibitors, addition of caffeine and ZM447439 resulted in improved accuracy in the detection of micronuclei yields up to 10 Gy from photons and 4 Gy of mixed neutrons-photons. When the dose-effect curves were fitted to take into account the turnover phenomenon observed at higher doses, best fitting was achieved when the combination of both inhibitors was used. These techniques permit reliable dose reconstruction after high doses of radiation with a method that can be adapted to high-throughput automated sample processing systems.


Assuntos
Citogenética , Doses de Radiação , Radiometria , Adulto , Benzamidas/farmacologia , Cafeína/farmacologia , Células Cultivadas , Relação Dose-Resposta à Radiação , Feminino , Humanos , Linfócitos/efeitos dos fármacos , Linfócitos/efeitos da radiação , Masculino , Testes para Micronúcleos , Pessoa de Meia-Idade , Nêutrons , Prótons , Quinazolinas/farmacologia
16.
Sci Rep ; 10(1): 6524, 2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32300151

RESUMO

Glioblastoma, the most lethal primary brain cancer, is extremely proliferative and invasive. Tumor cells at tumor/brain-interface often exist behind a functionally intact blood-brain barrier (BBB), and so are shielded from exposure to therapeutic drug concentrations. An ideal glioblastoma treatment needs to engage targets that drive proliferation as well as invasion, with brain penetrant therapies. One such target is the mitotic kinesin KIF11, which can be inhibited with ispinesib, a potent molecularly-targeted drug. Although, achieving durable brain exposures of ispinesib is critical for adequate tumor cell engagement during mitosis, when tumor cells are vulnerable, for efficacy. Our results demonstrate that the delivery of ispinesib is restricted by P-gp and Bcrp efflux at BBB. Thereby, ispinesib distribution is heterogeneous with concentrations substantially lower in invasive tumor rim (intact BBB) compared to glioblastoma core (disrupted BBB). We further find that elacridar-a P-gp and Bcrp inhibitor-improves brain accumulation of ispinesib, resulting in remarkably reduced tumor growth and extended survival in a rodent model of glioblastoma. Such observations show the benefits and feasibility of pairing a potentially ideal treatment with a compound that improves its brain accumulation, and supports use of this strategy in clinical exploration of cell cycle-targeting therapies in brain cancers.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Benzamidas/farmacologia , Proliferação de Células/efeitos dos fármacos , Cinesina/antagonistas & inibidores , Proteínas de Neoplasias/genética , Quinazolinas/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/antagonistas & inibidores , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Acridinas/química , Acridinas/farmacologia , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Encéfalo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Cinesina/genética , Camundongos , Terapia de Alvo Molecular , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Proteínas de Neoplasias/antagonistas & inibidores , Tetra-Hidroisoquinolinas/química , Tetra-Hidroisoquinolinas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Eur J Histochem ; 64(2)2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32236088

RESUMO

Schwann cells (SC) are characterized by a remarkable plasticity that enables them to promptly respond to nerve injury promoting axonal regeneration. In peripheral nerves after damage SC convert to a repair-promoting phenotype activating a sequence of supportive functions that drive myelin clearance, prevent neuronal death, and help axon growth and guidance. Regeneration of peripheral nerves after damage correlates inversely with thrombin levels. Thrombin is not only the key regulator of the coagulation cascade but also a protease with hormone-like activities that affects various cells of the central and peripheral nervous system mainly through the protease-activated receptor 1 (PAR1). Aim of the present study was to investigate if and how thrombin could affect the axon supportive functions of SC. In particular, our results show that the activation of PAR1 in rat SC cultures with low levels of thrombin or PAR1 agonist peptides induces the release of molecules, which favor neuronal survival and neurite elongation. Conversely, the stimulation of SC with high levels of thrombin or PAR1 agonist peptides drives an opposite effect inducing SC to release factors that inhibit the extension of neurites. Moreover, high levels of thrombin administered to sciatic nerve ex vivo explants induce a dramatic change in SC morphology causing disappearance of the Cajal bands, enlargement of the Schmidt-Lanterman incisures and calcium-mediated demyelination of the paranodes. Our results indicate thrombin as a novel modulator of SC plasticity potentially able to favor or inhibit SC pro-regenerative properties according to its level at the site of lesion.


Assuntos
Neurogênese/efeitos dos fármacos , Nós Neurofibrosos/efeitos dos fármacos , Células de Schwann/efeitos dos fármacos , Trombina/farmacologia , Animais , Cálcio/metabolismo , Feminino , Masculino , Neuritos/efeitos dos fármacos , Células PC12 , Pirróis/farmacologia , Quinazolinas/farmacologia , Ratos , Ratos Wistar , Receptor PAR-1/metabolismo , Nervo Isquiático/efeitos dos fármacos , Tapsigargina/farmacologia
18.
Anticancer Res ; 40(4): 1855-1866, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32234873

RESUMO

BACKGROUND/AIM: The resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), such as gefitinib or erlotinib, is considered a major challenge in the treatment of patients with non-small cell lung cancer (NSCLC). Herein, we identified the critical roles of anterior gradient 2 (AGR2) in gefitinib (Gef) resistance of mutant NSCLC cells. MATERIALS AND METHODS: Using datasets from a pair of NSCLC-sensitive and NSCLC-resistant cells, immunoblotting, immunofluorescence and immunohistochemistry, and cell viability assays were applied to identify the effects of AGR2. RESULTS: AGR2 was found to be significantly over-expressed in Gef-resistant cells and was highly associated with drug resistance, proliferation, migration, and invasion of cancer cells. Moreover, AGR2 and ADAMTS6 formed a negative feedback loop in drug-resistant cells. CONCLUSION: Modulation of overexpression of AGR2 in mutant NSCLC cells may be an attractive therapeutic strategy for the treatment of EGFR-TKI-resistant NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Mucoproteínas/genética , Proteínas Oncogênicas/genética , Inibidores de Proteínas Quinases/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Movimento Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Cloridrato de Erlotinib/farmacologia , Gefitinibe/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Mutação , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Quinazolinas/farmacologia
19.
Oncol Rep ; 43(6): 2073-2082, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32186773

RESUMO

Mutations of p53 occur in approximately 50% of advanced non­small cell lung cancer (NSCLC) cases, leading to loss of tumor suppressive function and/or gain of p53 oncogenic activity. Reactivation of mutant p53 and consequently induction of apoptosis in cancer cells is the goal of p53­targeted therapy. Recently, several p53 mutant reactivating compounds were discovered including SCH 529074. However, the role of SCH 529074 in NSCLC has not been fully explored. In the present study, the effects of this compound on cell survival, cell cycle progression, induction of apoptosis and modulation of cell signaling in p53 mutant NSCLC cells (H1975, H322 and H157) and p53 wild­type NSCLC cells (A549), was investigated. Cell­based functional assays, real­time RT­qPCR and western blot assays were used. HCT116 [p53 wild­type (WT)] and HCT116 p53­/­ (p53 null) were used as control cells. The results demonstrated that SCH 529074 treatment caused significant reduction in cell viability and colony formation activity in p53 mutant, p53 WT and p53­deficient cells. The treatment of NSCLC cells with SCH 529074 resulted in a dose­dependent induction of apoptosis and G0/G1 cell cycle arrest, which was associated with the activation of caspases (3 and 7), p53­independent upregulation of p21 and PUMA as well as increased LC3II, a biomarker of autophagy. The combination treatment with the autophagy inhibitor chloroquine (CQ) and SCH 529074 led to decreased cell viability, colony formation and increased induction of apoptosis. The data indicated that SCH 529074 may exert its growth inhibitory function in a p53­independent manner in NSCLC cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Mutação , Piperazinas/farmacologia , Quinazolinas/farmacologia , Proteína Supressora de Tumor p53/genética , Células A549 , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cloroquina/farmacologia , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos
20.
Biochem Biophys Res Commun ; 526(1): 158-164, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32201081

RESUMO

Epithelial ovarian cancer (EOC) is the most lethal gynecological malignancy, with an overall 5-year survival rate of only 30%. EOC is associated with drug resistance, frequent recurrence, and poor prognosis. A major contributor toward drug resistance might be cancer stem cells (CSCs), which may remain after chemotherapy. Here, we aimed to find therapeutic agents that target ovarian CSCs. We performed a high-throughput screening using the Clinical Compound Library with a sphere culture of A2780 EOCs. Poziotinib, a pan-human epidermal growth factor receptor (HER) inhibitor, decreased sphere formation, viability, and proliferation, and induced G1 cell cycle arrest and apoptosis in ovarian CSCs. In addition, poziotinib suppressed stemness and disrupted downstream signaling of Wnt/ß-catenin, Notch, and Hedgehog pathways, which contribute to many characteristics of CSCs. Interestingly, HER4 was overexpressed in ovarian CSCs and Poziotinib reduced the phosphorylation of STAT5, AKT, and ERK, which are regulated by HER4. Our results suggest that HER4 may be a promising therapeutic target for ovarian CSCs, and that poziotinib may be an effective therapeutic option for the prevention of ovarian cancer recurrence.


Assuntos
Células-Tronco Neoplásicas/patologia , Neoplasias Ovarianas/patologia , Quinazolinas/farmacologia , Receptor ErbB-4/metabolismo , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais , Apoptose/efeitos dos fármacos , Apoptose/genética , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Feminino , Fase G1/efeitos dos fármacos , Fase G1/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas Hedgehog/metabolismo , Humanos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Neoplasias Ovarianas/genética , Fosforilação/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Notch/metabolismo , Transdução de Sinais/efeitos dos fármacos , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , beta Catenina/metabolismo
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