Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 648
Filtrar
1.
Molecules ; 26(4)2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33546391

RESUMO

Herein, the activity of adamantanyl-tethered-biphenyl amines (ATBAs) as oestrogen receptor alpha (ERα) modulating ligands is reported. Using an ERα competitor assay it was demonstrated that ATBA compound 3-(adamantan-1-yl)-4-methoxy-N-(4-(trifluoromethyl) phenyl) aniline (AMTA) exhibited an inhibitory concentration 50% (IC50) value of 62.84 nM and demonstrated better binding affinity compared to tamoxifen (IC50 = 79.48 nM). Treatment of ERα positive (ER+) mammary carcinoma (MC) cells (Michigan Cancer Foundation-7 (MCF7)) with AMTA significantly decreased cell viability at an IC50 value of 6.4 µM. AMTA treatment of MC cell-generated three-dimensional (3D) spheroids resulted in significantly decreased cell viability. AMTA demonstrated a superior inhibitory effect compared to tamoxifen-treated MC cell spheroids. Subsequently, by use of an oestrogen response element (ERE) luciferase reporter construct, it was demonstrated that AMTA treatment significantly deceased ERE transcriptional activity in MC cells. Concordantly, AMTA treatment of MC cells also significantly decreased protein levels of oestrogen-regulated CCND1 in a dose-dependent manner. In silico molecular docking analysis suggested that AMTA compounds interact with the ligand-binding domain of ERα compared to the co-crystal ligand, 5-(4-hydroxyphenoxy)-6-(3-hydroxyphenyl)-7- methylnaphthalen-2-ol. Therefore, an analogue of AMTA may provide a structural basis to develop a newer class of ERα partial agonists.


Assuntos
Antineoplásicos/farmacologia , Compostos de Bifenilo/farmacologia , Neoplasias da Mama , Receptor alfa de Estrogênio , Proteínas de Neoplasias , Animais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Células MCF-7 , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo
2.
Int J Mol Sci ; 22(2)2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33451133

RESUMO

Breast cancer (BC) is the most common cancer among women worldwide. More than 70% of BC cases express estrogen receptor alpha (ERα), a central transcription factor that stimulates the proliferation of breast cancer cells, usually in the presence of estrogen. While most cases of ER-positive BC initially respond to antiestrogen therapies, a high percentage of cases develop resistance to treatment over time. The recent discovery of mutated forms of ERα that result in constitutively active forms of the receptor in the metastatic-resistance stage of BC has provided a strong rationale for the development of new antiestrogens. These molecules targeting clinically relevant ERα mutants and a combination with other pharmacological inhibitors of specific pathways may constitute alternative treatments to improve clinical practice in the fight against metastatic-resistant ER-positive BC. In this review, we summarize the latest advances regarding the particular involvement of point mutations of ERα in endocrine resistance. We also discuss the involvement of synonymous ERα mutations with respect to co-translational folding of the receptor and ribosome biogenesis in breast carcinogenesis.


Assuntos
Biomarcadores Tumorais , Neoplasias da Mama/etiologia , Neoplasias da Mama/metabolismo , Mutação , Receptores Estrogênicos/genética , Animais , Antineoplásicos Hormonais/farmacologia , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Gerenciamento Clínico , Suscetibilidade a Doenças , Antagonistas de Estrogênios/farmacologia , Antagonistas de Estrogênios/uso terapêutico , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/química , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Estrogênios/farmacologia , Estrogênios/uso terapêutico , Feminino , Humanos , Terapia de Alvo Molecular , Mutação de Sentido Incorreto , Receptores Estrogênicos/antagonistas & inibidores , Receptores Estrogênicos/química , Receptores Estrogênicos/metabolismo , Mutação Silenciosa , Relação Estrutura-Atividade
3.
Nucleic Acids Res ; 48(19): 10768-10784, 2020 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-32986841

RESUMO

Estrogen receptor alpha (ERα) signaling pathway is essential for ERα-positive breast cancer progression and endocrine therapy resistance. Bromodomain PHD Finger Transcription Factor (BPTF) associated protein of 18kDa (BAP18) has been recognized as a crucial H3K4me3 reader. However, the whole genomic occupation of BAP18 and its biological function in breast cancer is still elusive. Here, we found that higher expression of BAP18 in ERα-positive breast cancer is positively correlated with poor prognosis. ChIP-seq analysis further demonstrated that the half estrogen response elements (EREs) and the CCCTC binding factor (CTCF) binding sites are the significant enrichment sites found in estrogen-induced BAP18 binding sites. Also, we provide the evidence to demonstrate that BAP18 as a novel co-activator of ERα is required for the recruitment of COMPASS-like core subunits to the cis-regulatory element of ERα target genes in breast cancer cells. BAP18 is recruited to the promoter regions of estrogen-induced genes, accompanied with the enrichment of the lysine 4-trimethylated histone H3 tail (H3K4me3) in the presence of E2. Furthermore, BAP18 promotes cell growth and associates the sensitivity of antiestrogen in ERα-positive breast cancer. Our data suggest that BAP18 facilitates the association between ERα and COMPASS-like core subunits, which might be an essential epigenetic therapeutic target for breast cancer.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Proteínas de Ligação a DNA/genética , Resistencia a Medicamentos Antineoplásicos , Receptor alfa de Estrogênio/genética , Código das Histonas , Animais , Antineoplásicos Hormonais/farmacologia , Antineoplásicos Hormonais/uso terapêutico , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proteínas de Ligação a DNA/metabolismo , Moduladores de Receptor Estrogênico/farmacologia , Moduladores de Receptor Estrogênico/uso terapêutico , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Células MCF-7 , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Elementos de Resposta
4.
Lancet Oncol ; 21(10): 1296-1308, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32919527

RESUMO

BACKGROUND: Circulating tumour DNA (ctDNA) testing might provide a current assessment of the genomic profile of advanced cancer, without the need to repeat tumour biopsy. We aimed to assess the accuracy of ctDNA testing in advanced breast cancer and the ability of ctDNA testing to select patients for mutation-directed therapy. METHODS: We did an open-label, multicohort, phase 2a, platform trial of ctDNA testing in 18 UK hospitals. Participants were women (aged ≥18 years) with histologically confirmed advanced breast cancer and an Eastern Cooperative Oncology Group performance status 0-2. Patients had completed at least one previous line of treatment for advanced breast cancer or relapsed within 12 months of neoadjuvant or adjuvant chemotherapy. Patients were recruited into four parallel treatment cohorts matched to mutations identified in ctDNA: cohort A comprised patients with ESR1 mutations (treated with intramuscular extended-dose fulvestrant 500 mg); cohort B comprised patients with HER2 mutations (treated with oral neratinib 240 mg, and if oestrogen receptor-positive with intramuscular standard-dose fulvestrant); cohort C comprised patients with AKT1 mutations and oestrogen receptor-positive cancer (treated with oral capivasertib 400 mg plus intramuscular standard-dose fulvestrant); and cohort D comprised patients with AKT1 mutations and oestrogen receptor-negative cancer or PTEN mutation (treated with oral capivasertib 480 mg). Each cohort had a primary endpoint of confirmed objective response rate. For cohort A, 13 or more responses among 78 evaluable patients were required to infer activity and three or more among 16 were required for cohorts B, C, and D. Recruitment to all cohorts is complete and long-term follow-up is ongoing. This trial is registered with ClinicalTrials.gov, NCT03182634; the European Clinical Trials database, EudraCT2015-003735-36; and the ISRCTN registry, ISRCTN16945804. FINDINGS: Between Dec 21, 2016, and April 26, 2019, 1051 patients registered for the study, with ctDNA results available for 1034 patients. Agreement between ctDNA digital PCR and targeted sequencing was 96-99% (n=800, kappa 0·89-0·93). Sensitivity of digital PCR ctDNA testing for mutations identified in tissue sequencing was 93% (95% CI 83-98) overall and 98% (87-100) with contemporaneous biopsies. In all cohorts, combined median follow-up was 14·4 months (IQR 7·0-23·7). Cohorts B and C met or exceeded the target number of responses, with five (25% [95% CI 9-49]) of 20 patients in cohort B and four (22% [6-48]) of 18 patients in cohort C having a response. Cohorts A and D did not reach the target number of responses, with six (8% [95% CI 3-17]) of 74 in cohort A and two (11% [1-33]) of 19 patients in cohort D having a response. The most common grade 3-4 adverse events were raised gamma-glutamyltransferase (13 [16%] of 80 patients; cohort A); diarrhoea (four [25%] of 20; cohort B); fatigue (four [22%] of 18; cohort C); and rash (five [26%] of 19; cohort D). 17 serious adverse reactions occurred in 11 patients, and there was one treatment-related death caused by grade 4 dyspnoea (in cohort C). INTERPRETATION: ctDNA testing offers accurate, rapid genotyping that enables the selection of mutation-directed therapies for patients with breast cancer, with sufficient clinical validity for adoption into routine clinical practice. Our results demonstrate clinically relevant activity of targeted therapies against rare HER2 and AKT1 mutations, confirming these mutations could be targetable for breast cancer treatment. FUNDING: Cancer Research UK, AstraZeneca, and Puma Biotechnology.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/tratamento farmacológico , DNA Tumoral Circulante/sangue , Terapia de Alvo Molecular , Adulto , Idoso , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/genética , Feminino , Fulvestranto/uso terapêutico , Genótipo , Humanos , Pessoa de Meia-Idade , Mutação , PTEN Fosfo-Hidrolase/genética , Estudos Prospectivos , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/genética , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Quinolinas/uso terapêutico , Receptor ErbB-2/genética , Receptores Estrogênicos/antagonistas & inibidores , Receptores Estrogênicos/genética , Receptores Estrogênicos/metabolismo , Resultado do Tratamento
5.
Einstein (Sao Paulo) ; 18: eAO4560, 2020.
Artigo em Inglês, Português | MEDLINE | ID: mdl-32321078

RESUMO

OBJECTIVE: To investigate if ICI 182,780 (fulvestrant), a selective estrogen receptor alpha/beta (ERα/ERß) antagonist, and G-1, a selective G-protein-coupled receptor (GPER) agonist, can potentially induce autophagy in breast cancer cell lines MCF-7 and SKBr3, and how G-1 affects cell viability. METHODS: Cell viability in MCF-7 and SKBr3 cells was assessed by the MTT assay. To investigate the autophagy flux, MCF-7 cells were transfected with GFP-LC3, a marker of autophagosomes, and analyzed by real-time fluorescence microscopy. MCF-7 and SKBr3 cells were incubated with acridine orange for staining of acidic vesicular organelles and analyzed by flow cytometry as an indicator of autophagy. RESULTS: Regarding cell viability in MCF-7 cells, ICI 182,780 and rapamycin, after 48 hours, led to decreased cell proliferation whereas G-1 did not change viability over the same period. The data showed that neither ICI 182,780 nor G-1 led to increased GFP-LC3 puncta in MCF-7 cells over the 4-hour observation period. The cytometry assay showed that ICI 182,780 led to a higher number of acidic vesicular organelles in MCF-7 cells. G-1, in turn, did not have this effect in any of the cell lines. In contrast, ICI 182,780 and G-1 did not decrease cell viability of SKBr3 cells or induce formation of acidic vesicular organelles, which corresponds to the final step of the autophagy process in this cell line. CONCLUSION: The effect of ICI 182,780 on increasing acidic vesicular organelles in estrogen receptor-positive breast cancer cells appears to be associated with its inhibitory effect on estrogen receptors, and GPER does notseem to be involved. Understanding these mechanisms may guide further investigations of these receptors' involvement in cellular processes of breast cancer resistance.


Assuntos
Autofagia/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Antagonistas do Receptor de Estrogênio/farmacologia , Fulvestranto/farmacologia , Receptores Acoplados a Proteínas-G/agonistas , Análise de Variância , Western Blotting , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor beta de Estrogênio/antagonistas & inibidores , Feminino , Citometria de Fluxo/métodos , Humanos , Células MCF-7 , Receptores Acoplados a Proteínas-G/análise , Reprodutibilidade dos Testes , Sirolimo/farmacologia , Fatores de Tempo , Transfecção/métodos
6.
Biochem Pharmacol ; 177: 113989, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32330493

RESUMO

Endocrine therapy is currently the main therapeutic approach for estrogen receptor-positive (ER+) breast cancer, the most frequent subtype of breast cancer in women worldwide. For this subtype of tumors, the current clinical treatment includes aromatase inhibitors (AIs) and anti-estrogenic compounds, such as Tamoxifen and Fulvestrant, being AIs the first-line treatment option for post-menopausal women. Moreover, the recent guidelines also suggest the use of these compounds by pre-menopausal women after suppressing ovaries function. However, besides its therapeutic efficacy, the prolonged use of this type of therapies may lead to the development of several adverse effects, as well as, endocrine resistance, limiting the effectiveness of such treatments. In order to surpass this issues and clinical concerns, during the last years, several studies have been suggesting alternative therapeutic approaches, considering the function of aromatase, ERα and ERß. Here, we review the structural and functional features of these three targets and their importance in ER+ breast cancer treatment, as well as, the current treatment strategies used in clinic, emphasizing the importance of the development of multi-target compounds able to simultaneously modulate these key targets, as a novel and promising therapeutic strategy for this type of cancer.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Aromatase/genética , Neoplasias da Mama/tratamento farmacológico , Receptor alfa de Estrogênio/genética , Androstadienos/uso terapêutico , Aromatase/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/antagonistas & inibidores , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Fadrozol/uso terapêutico , Feminino , Fulvestranto/uso terapêutico , Expressão Gênica , Humanos , Terapia de Alvo Molecular , Tamoxifeno/uso terapêutico
7.
Sci Rep ; 10(1): 4227, 2020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-32144339

RESUMO

Laryngeal squamous cell carcinoma (LSCC) responds to 17ß-estradiol via estrogen-receptor (ER, transcribed from ESR1) dependent mechanisms, but is not recognized as a hormonally responsive cancer. 17ß-estradiol production by LSCC cell lines UM-SCC-11A and UM-SCC-12 was examined. Wild type (WT) and ESR1-silenced LSCC cultures and xenografts were examined for 17ß-estradiol responsiveness in vivo. 14 LSCC and surrounding epithelial samples at various pathological stages were obtained from patients; ERα and ERß expression were verified using data from the total cancer genome atlas. UM-SCC-11A and UM-SCC-12 both produce 17ß-estradiol, but only UM-SCC-12, not UM-SCC-11A, xenograft tumors grow larger in vivo in response to systemic 17ß-estradiol treatments. ERα66 and ERα36 expression inversely correlated with clinical cancer stage and tumor burden. LSCC ERα66 expression was higher compared to surrounding epithelia in indolent samples but lower in aggressive LSCC. ERß expression was highly variable. High ESR1 expression correlated with improved survival in LSCC. Loss of ERα66 expression inversely correlated with prognosis in LSCC. ERα66 may be a histopathological marker of aggression in LSCC.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/patologia , Estradiol/metabolismo , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor beta de Estrogênio/antagonistas & inibidores , Neoplasias Laríngeas/patologia , Idoso , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/metabolismo , Masculino , Pessoa de Meia-Idade , Prognóstico , Células Tumorais Cultivadas
8.
Breast Cancer Res Treat ; 180(2): 359-368, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32030569

RESUMO

PURPOSE: Selective estrogen receptor degrader (SERD) has proven clinically effective in treating advanced or metastatic breast cancer since the approval of fulvestrant by FDA in 2002. Recent expansion of indications as a first line monotherapy and as combination therapy with CDK4/6 inhibitors further extends its clinical utility as an efficacious breast cancer endocrine regimen. However, the poor pharmacokinetic properties of fulvestrant and its injection-only administration route has driven continued efforts to develop orally bioavailability SERD that could potentially improve clinical response to SERD treatment. GLL398, a boron-modified GW5638 analog, showed superior oral bioavailability, while retaining both antiestrogenic activity and ER degrading efficacy at a potency level comparable to the more active metabolite of GW5638, GW7604. METHODS: Here we used molecular modeling, ER (Y537S) binding assay, MCF-7 Xenograft tumor, and patient-derived xenograft (PDX) tumor model to conduct further studies on the pharmacology and metabolism of GLL398. RESULTS: Consistent with GLL398's robust activities in breast cancer cells that either are tamoxifen resistant or express constitutively active, mutant ESR1 (Y537S), it was found to bind the mutant ERY537S with high affinity. Molecular modeling of the binding mode of GLL398 to ER also found its molecular interactions consistent with the experimentally determined high binding affinity towards WT ER and ERY537S. To test the in vivo efficacy of GLL398, mice bearing MCF-7-derived xenograft breast tumors and patient-derived xenograft tumors harboring ERY537S were treated with GLL398 which potently inhibited tumor growth in mice. CONCLUSIONS: This study demonstrates GLL398 is an oral SERD that has therapeutic efficacy in clinically relevant breast tumor models.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Receptor alfa de Estrogênio/antagonistas & inibidores , Proteólise , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Administração Oral , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Camundongos , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Int J Mol Sci ; 21(3)2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32019136

RESUMO

Alpha-fetoprotein (AFP) is a major embryo- and tumor-associated protein capable of binding and transporting a variety of hydrophobic ligands, including estrogens. AFP has been shown to inhibit estrogen receptor (ER)-positive tumor growth, which can be attributed to its estrogen-binding ability. Despite AFP having long been investigated, its three-dimensional (3D) structure has not been experimentally resolved and molecular mechanisms underlying AFP-ligand interaction remains obscure. In our study, we constructed a homology-based 3D model of human AFP (HAFP) with the purpose of molecular docking of ERα ligands, three agonists (17ß-estradiol, estrone and diethylstilbestrol), and three antagonists (tamoxifen, afimoxifene and endoxifen) into the obtained structure. Based on the ligand-docked scoring functions, we identified three putative estrogen- and antiestrogen-binding sites with different ligand binding affinities. Two high-affinity binding sites were located (i) in a tunnel formed within HAFP subdomains IB and IIA and (ii) on the opposite side of the molecule in a groove originating from a cavity formed between domains I and III, while (iii) the third low-affinity binding site was found at the bottom of the cavity. Here, 100 ns molecular dynamics (MD) simulation allowed us to study their geometries and showed that HAFP-estrogen interactions were caused by van der Waals forces, while both hydrophobic and electrostatic interactions were almost equally involved in HAFP-antiestrogen binding. Molecular mechanics/Generalized Born surface area (MM/GBSA) rescoring method exploited for estimation of binding free energies (ΔGbind) showed that antiestrogens have higher affinities to HAFP as compared to estrogens. We performed in silico point substitutions of amino acid residues to confirm their roles in HAFP-ligand interactions and showed that Thr132, Leu138, His170, Phe172, Ser217, Gln221, His266, His316, Lys453, and Asp478 residues, along with two disulfide bonds (Cys224-Cys270 and Cys269-Cys277), have key roles in both HAFP-estrogen and HAFP-antiestrogen binding. Data obtained in our study contribute to understanding mechanisms underlying protein-ligand interactions and anticancer therapy strategies based on ERα-binding ligands.


Assuntos
Estradiol/metabolismo , Moduladores de Receptor Estrogênico/metabolismo , Receptor alfa de Estrogênio/metabolismo , Estrogênios/metabolismo , alfa-Fetoproteínas/metabolismo , Sequência de Aminoácidos , Substituição de Aminoácidos , Sítios de Ligação , Receptor alfa de Estrogênio/agonistas , Receptor alfa de Estrogênio/antagonistas & inibidores , Feminino , Humanos , Ligantes , Modelos Moleculares , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Mutagênese , Alinhamento de Sequência
10.
Horm Cancer ; 11(2): 76-86, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32008217

RESUMO

There is a desperate need in the field for mouse mammary tumors and cell lines that faithfully mimic estrogen receptor (ER) expression and activity found in human breast cancers. We found that several mouse mammary cancer cell lines express ER but fail to demonstrate classical estrogen-driven proliferation or transcriptional activity. We investigated whether these cell lines may be used to model tamoxifen resistance by using small molecule inhibitors to signaling pathways known to contribute to resistance. We found that the combination of NFκB inhibition and ER antagonists significantly reduced cell proliferation in vitro, as well as growth of syngeneic tumors. Surprisingly, we found that ER was localized to the cytoplasm, regardless of any type of treatment. Based on this, we probed extra-nuclear functions of ER and found that co-inhibition of ER and NFκB led to an increase in oxidative stress and apoptosis. Together, these findings suggest that cytoplasmic ER and NFκB may play redundant roles in protecting mammary cancer cells from oxidative stress and cell death. Although this study has not identified a mouse model with classical ER activity, cytoplasmic ER has been described in a small subset of human breast tumors, suggesting that these findings may be relevant for some breast cancer patients.


Assuntos
Receptor alfa de Estrogênio/metabolismo , Neoplasias Mamárias Experimentais/metabolismo , NF-kappa B/metabolismo , Animais , Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Sobrevivência Celular/fisiologia , Citoplasma/metabolismo , Fumarato de Dimetilo/farmacologia , Modelos Animais de Doenças , Receptor alfa de Estrogênio/antagonistas & inibidores , Feminino , Humanos , Células MCF-7 , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/patologia , Camundongos , NF-kappa B/antagonistas & inibidores , Estresse Oxidativo/fisiologia , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Tamoxifeno/farmacologia
11.
Oncogene ; 39(12): 2493-2508, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31996784

RESUMO

Early studies indicated that estrogen receptor α (ERα) might impact the progression of hepatocellular carcinoma (HCC). However, the detailed mechanisms, especially its linkage to the gelsolin (GSN)-mediated cell invasion, remain unclear. Here we found that ERα could decrease HCC cell invasion via suppressing the circular RNA-SMG1.72 (circRNA-SMG1.72) expression via transcriptional regulation through directly binding to the 5' promoter region of its host gene SMG1, We showed that ERα-suppressed circ-SMG1.72 could sponge and inhibit the expression of the microRNA (miRNA, miR), miR-141-3p, which could then result in increasing the GSN messenger RNA translation via reduced miR binding to its 3' untranslated region (3'UTR). The preclinical study using an in vivo mouse model with orthotopic xenografts of HCC cells confirmed the in vitro data, and the human HCC clinical sample survey and tissue staining also confirmed the linkage of ERα/miR-141-3p/GSN signaling to the HCC progression. Together, our findings suggest that ERα can suppress HCC cell invasion via altering the ERα/circRNA-SMG1.72/miR-141-3p/GSN signaling, and targeting this newly identified signaling with small molecules may help in the development of novel therapies to better suppress the HCC progression.


Assuntos
Carcinoma Hepatocelular/metabolismo , Receptor alfa de Estrogênio/metabolismo , Gelsolina/metabolismo , Neoplasias Hepáticas/metabolismo , MicroRNAs/metabolismo , Invasividade Neoplásica , Proteínas Serina-Treonina Quinases/metabolismo , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Receptor alfa de Estrogênio/antagonistas & inibidores , Gelsolina/antagonistas & inibidores , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , MicroRNAs/antagonistas & inibidores , Invasividade Neoplásica/prevenção & controle , RNA Circular/efeitos dos fármacos , RNA Neoplásico/efeitos dos fármacos , RNA Neoplásico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Taxa de Sobrevida
12.
Eur J Med Chem ; 187: 111967, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31865016

RESUMO

Proteolysis-targeting chimera (PROTAC) could selectively degrade target protein and may become a promising strategy for treating estrogen receptor α (ERα) positive breast cancers. Here, we designed penetrated peptide-based PROTACs by constructing an N-terminal lactam cyclic to improve proteolytic stability and cell penetration. We used a lactam cyclic peptide as ERα binding ligand, 6-aminocaproic acid as a linker, and a hydroxylated pentapeptide structure for recruiting E3 ligase to obtain heterobifunctional compounds. The resulting optimized compound I-6 selectively recruited ERα to the E3 ligase complex for promoting the degradation of ERα. Compound I-6 possessed strong effect on MCF-7 cell toxicity (IC50 ∼9.7 µM) and significantly enhanced activities in inducing ERα degradation. Meanwhile, I-6 performed much stronger potency in inhibition of tumors growth than tamoxifen. This work is a successful template to construct PROTACs based on cell-permeable peptides, which could extend the chemical space of PROTACs.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Peptídeos Penetradores de Células/farmacologia , Receptor alfa de Estrogênio/antagonistas & inibidores , Proteólise/efeitos dos fármacos , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Peptídeos Penetradores de Células/síntese química , Peptídeos Penetradores de Células/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade
13.
Cancer Lett ; 469: 78-88, 2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-31629931

RESUMO

Selective estrogen receptor modulators (SERMs) are a class of structurally diverse compounds, which have been extensively used to treat hormone-responsive cancers due to their unique partially agonistic and antagonistic properties toward estrogen receptors. Our previous studies have identified a three-dimensional SERM, oxabicycloheptene sulfonate (OBHS), as an estrogen receptor α (ERα) ligand, which is effective for the prevention and treatment of estrogen-dependent endometriosis in vivo. Here, using genome-wide ChIP-seq and RNA-seq analysis, we report that OBHS rapidly induces genome-wide ERα occupancy and acts as a partial agonist and antagonist for ERα. Interestingly, OBHS downregulates the homologous recombination and repair (HRR) modules, resulting in increased DNA damage, apoptosis and cell cycle arrest, inducing synthetic lethality with poly (ADP-ribose) polymerase (PARP) inhibitor olaparib through ERα antagonism. Mechanistically, OBHS impairs the RNA polymerase II (Pol II) loading at the promoters of estrogen-responsive HRR genes. Furthermore, combination therapy of OBHS with olaparib significantly reduces the tumour burden and delays the progression of breast cancer in vivo. Together, our studies not only characterise a novel SERM which uniquely targets the homologous recombination and repair programmes through ERα antagonism but also propose a synthetic lethal strategy by combining OBHS with PARP inhibitor olaparib for ERα-responsive cancers.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/tratamento farmacológico , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Antagonistas do Receptor de Estrogênio/farmacologia , Reparo de DNA por Recombinação/efeitos dos fármacos , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Ácidos Sulfônicos/farmacologia , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Apoptose/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Chlorocebus aethiops , Sequenciamento de Cromatina por Imunoprecipitação , Antagonistas do Receptor de Estrogênio/uso terapêutico , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Camundongos , Estrutura Molecular , Ftalazinas/farmacologia , Ftalazinas/uso terapêutico , Piperazinas/farmacologia , Piperazinas/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Regiões Promotoras Genéticas/genética , RNA Polimerase II/antagonistas & inibidores , RNA Polimerase II/metabolismo , RNA-Seq , Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Relação Estrutura-Atividade , Ácidos Sulfônicos/uso terapêutico , Mutações Sintéticas Letais/efeitos dos fármacos , Células Vero , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Breast Cancer Res Treat ; 179(1): 67-77, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31562570

RESUMO

PURPOSE: Fulvestrant is a selective estrogen receptor downregulator (SERD) that is approved for first- or second-line use as a single agent or in combination with cyclin dependent kinase or phosphatidylinositol 3-kinase inhibitors for the treatment of metastatic breast cancer. Fulvestrant exhibits exceptionally effective antitumor activity in preclinical models of breast cancer, a success that has been attributed to its robust SERD activity despite modest receptor downregulation in patient tumors. By modeling human exposures in animal models we probe the absolute need for SERD activity. METHODS: Three xenograft models of endocrine therapy-resistant breast cancer were used to evaluate the efficacy of fulvestrant administered in doses historically used in preclinical studies in the field or by using a dose regimen intended to model clinical exposure levels. Pharmacokinetic and pharmacodynamic analyses were conducted to evaluate plasma exposure and intratumoral ER downregulation. RESULTS: A clinically relevant 25 mg/kg dose of fulvestrant exhibited antitumor efficacy comparable to the historically used 200 mg/kg dose, but at this lower dose it did not result in robust ER downregulation. Further, the antitumor efficacy of the lower dose of fulvestrant was comparable to that observed for other oral SERDs currently in development. CONCLUSION: The use of clinically unachievable exposure levels of fulvestrant as a benchmark in preclinical development of SERDs may negatively impact the selection of those molecules that are advanced for clinical development. Further, these studies suggest that antagonist efficacy, as opposed to SERD activity, is likely to be the primary driver of clinical response.


Assuntos
Antineoplásicos Hormonais/farmacocinética , Neoplasias da Mama/tratamento farmacológico , Antagonistas do Receptor de Estrogênio/farmacocinética , Fulvestranto/farmacocinética , Administração Oral , Animais , Antineoplásicos Hormonais/administração & dosagem , Relação Dose-Resposta a Droga , Antagonistas do Receptor de Estrogênio/administração & dosagem , Receptor alfa de Estrogênio/antagonistas & inibidores , Feminino , Fulvestranto/administração & dosagem , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
15.
J Invest Dermatol ; 140(3): 593-601.e7, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31476316

RESUMO

Systemic sclerosis primarily affects women. This sex bias raises the question on the role female hormones could play in the development of fibrosis, which is largely unknown. Our aim was to evaluate the effects of estrogens in the development of experimental dermal fibrosis, in the mouse models of bleomycin-induced dermal fibrosis and tight skin (Tsk-1) mice, and on the activation of dermal fibroblasts by transforming growth factor-ß (TGF-ß). Estrogen inhibition, obtained through gene inactivation for the estrogen receptor-αknockout or treatment with tamoxifen, exacerbated skin fibrosis in the bleomycin model and in the Tsk-1 mice. In the dermal fibroblasts, treatment with 17-ß-estradiol significantly decreased the stimulatory effects of TGF-ß on collagen synthesis and myofibroblast differentiation, decreased the activation of canonical TGF-ß signaling, and markedly reduced the expression of the TGF-ß target genes. Tamoxifen reversed the inhibitory effects of estrogens by restoring Smad2/3 phosphorylation and TGF-ß-induced collagen synthesis. Our results demonstrate a beneficial effect of estrogens in dermal fibrosis. Estrogens reduce the TGF-ß-dependent activation of dermal fibroblasts, and estrogen inhibition leads to a more severe experimental dermal fibrosis. These findings are consistent with the prominent development of systemic sclerosis in postmenopausal women and the greater severity of the disease in men.


Assuntos
Receptor alfa de Estrogênio/antagonistas & inibidores , Estrogênios/metabolismo , Escleroderma Sistêmico/patologia , Pele/patologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Biópsia , Bleomicina/toxicidade , Células Cultivadas , Colágeno/biossíntese , Modelos Animais de Doenças , Antagonistas de Estrogênios/administração & dosagem , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Estrogênios/administração & dosagem , Feminino , Fibroblastos , Humanos , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Cultura Primária de Células , Escleroderma Sistêmico/diagnóstico , Índice de Gravidade de Doença , Fatores Sexuais , Transdução de Sinais/efeitos dos fármacos , Pele/efeitos dos fármacos , Tamoxifeno/administração & dosagem
16.
Gut ; 69(1): 158-167, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30833451

RESUMO

OBJECTIVE: Hepatitis D virus (HDV) is a circular RNA virus coinfecting hepatocytes with hepatitis B virus. Chronic hepatitis D results in severe liver disease and an increased risk of liver cancer. Efficient therapeutic approaches against HDV are absent. DESIGN: Here, we combined an RNAi loss-of-function and small molecule screen to uncover host-dependency factors for HDV infection. RESULTS: Functional screening unravelled the hypoxia-inducible factor (HIF)-signalling and insulin-resistance pathways, RNA polymerase II, glycosaminoglycan biosynthesis and the pyrimidine metabolism as virus-hepatocyte dependency networks. Validation studies in primary human hepatocytes identified the carbamoyl-phosphatesynthetase 2, aspartate transcarbamylase and dihydroorotase (CAD) enzyme and estrogen receptor alpha (encoded by ESR1) as key host factors for HDV life cycle. Mechanistic studies revealed that the two host factors are required for viral replication. Inhibition studies using N-(phosphonoacetyl)-L-aspartic acid and fulvestrant, specific CAD and ESR1 inhibitors, respectively, uncovered their impact as antiviral targets. CONCLUSION: The discovery of HDV host-dependency factors elucidates the pathogenesis of viral disease biology and opens therapeutic strategies for HDV cure.


Assuntos
Aspartato Carbamoiltransferase/genética , Ácido Aspártico/análogos & derivados , Carbamoil Fosfato Sintase (Glutamina-Hidrolizante)/genética , Di-Hidro-Orotase/genética , Receptor alfa de Estrogênio/metabolismo , Fulvestranto/farmacologia , Hepatite D Crônica/tratamento farmacológico , Ácido Fosfonoacéticos/análogos & derivados , Pirimidinas/biossíntese , Antivirais/farmacologia , Aspartato Carbamoiltransferase/antagonistas & inibidores , Aspartato Carbamoiltransferase/metabolismo , Ácido Aspártico/farmacologia , Carbamoil Fosfato Sintase (Glutamina-Hidrolizante)/antagonistas & inibidores , Carbamoil Fosfato Sintase (Glutamina-Hidrolizante)/metabolismo , Linhagem Celular , Di-Hidro-Orotase/antagonistas & inibidores , Di-Hidro-Orotase/metabolismo , Antagonistas do Receptor de Estrogênio/farmacologia , Receptor alfa de Estrogênio/antagonistas & inibidores , Inativação Gênica , Hepatite D Crônica/genética , Hepatite D Crônica/metabolismo , Vírus Delta da Hepatite/fisiologia , Hepatócitos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Resistência à Insulina , Estágios do Ciclo de Vida , Mutação com Perda de Função , Ácido Fosfonoacéticos/farmacologia , Interferência de RNA , RNA Interferente Pequeno/genética , RNA Viral/metabolismo , Transdução de Sinais , Replicação Viral
17.
Toxicol Appl Pharmacol ; 386: 114831, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31756431

RESUMO

The Organisation for Economic Co-operation and Development (OECD)-validated transactivation assay using the human estrogen receptor alpha (hERα) Hela9903 cell line is used for activity evaluation of hERα agonists and antagonists. Due to many advantages, this assay is broadly used as an initial screening process. However, response significantly higher from that of 17-ß estradiol (E2) was observed with phytoestrogens for concentrations commonly above 1 µM in previous studies. The main aim of this study was thus to ascertain the applicability of OECD protocol 455 for evaluation of estrogenic activity of natural flavonoids, including known phytoestrogens. The estrogenic activities of aglycones as well as of O-methylated and glycosylated flavonoids were evaluated. Supra-maximal luciferase activity was seen for most of the flavonoids tested at concentrations even below 1 µM. hERα-mediated luciferase expression was confirmed with the competition assay specified in OECD protocol 455. However, at concentrations above 1 µM, non-specific interactions were also observed. Instead of EC50 values, which could not be determined for most of the isoflavonoids tested, the concentrations corresponding to 10% (PC10) and 50% (PC50) of the maximum activity of the positive control, E2, were used for quantitative determination of estrogenic activities. Appropriate evaluation of the data obtained with the current OECD protocol 455 validated assay represents a valuable tool for initial screening of natural flavonoids for estrogenic activity.


Assuntos
Receptor alfa de Estrogênio/agonistas , Flavonoides/toxicidade , Fitoestrógenos/toxicidade , Testes de Toxicidade , Receptor alfa de Estrogênio/antagonistas & inibidores , Flavonoides/farmacologia , Células HeLa , Humanos , Luminescência , Fitoestrógenos/farmacologia , Testes de Toxicidade/métodos , Testes de Toxicidade/normas
18.
J Pharm Biomed Anal ; 178: 112884, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31606560

RESUMO

Cyto-architectural diversity of brain structures emphasizes need for analytical tools for discriminative investigation of distinctive neural structures. Glycogen is the major energy reserve in the brain. There is speculation that brain utilization of this fuel source may affect detection of hypoglycemia. To evaluate sex-specific regulation of glycogen mass and mobilization in the glucose-sensory ventromedial hypothalamic nucleus (VMN), current research coupled UHPLC-electrospray ionization mass spectrometric (LC-ESI-MS) analysis capabilities with novel derivatization protocols for high-sensitivity measurement of glucose and glycogen in small-volume neural tissue samples. This work also sought to demonstrate utility of pairing this approach with optimized Western blot methods for measurement of glycogen metabolic enzyme protein expression. Here, high-resolution micropunch dissection tools for discriminative isolation of VMN tissue were used in conjunction with newly developed glycogen analytical methods and an experimental treatment paradigm for intra-cranial hindbrain-targeted administration of estrogen receptor-alpha (ERα) or -beta (ERß) receptor antagonists to address the hypothesis that estradiol activates one or both hindbrain ER populations to exert sex-specific regulatory effects on VMN glycogen mass and hypoglycemia-associated mobilization. Outcomes validate a novel multi-analytical platform for investigation of in vivo sex-dimorphic regulation of glycogen metabolism in precisely-defined brain elements under conditions of energy balance versus imbalance. This combinatory approach will facilitate ongoing efforts to elucidate effects of acute versus chronic hypoglycemia on glycogen metabolism in characterized brain glucose-sensory loci and determine effects local glycogen mass and/or mobilization adaptions on sensory monitoring and signaling of recurring hypoglycemia in each sex.


Assuntos
Encéfalo/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Glicogênio/metabolismo , Hipoglicemia/diagnóstico , Animais , Estradiol/metabolismo , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor beta de Estrogênio/antagonistas & inibidores , Feminino , Masculino , Microdissecção/métodos , Ratos , Ratos Sprague-Dawley , Fatores Sexuais , Espectrometria de Massas por Ionização por Electrospray/métodos
19.
Molecules ; 24(21)2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31683895

RESUMO

Based upon hydrophobic feedback approaches, we designed and synthesized novel sulfur-containing ERα modulators (4 and 5) as breast cancer therapeutic drug candidates. The tetrahydrothiepine derivative 5a showed the highest binding affinity toward ERα because of its high hydrophobicity, and it acted as an agonist toward MCF-7 cell proliferation. The corresponding alkylamino derivative 5d maintained high binding affinity to ERα and potently inhibited MCF-7 cell proliferation (IC50: 0.09 µM). Docking simulation studies of compound 5d with the ERα BD revealed that the large hydrophobic moiety of compound 5d fit well into the hydrophobic pocket of the ERα LBD and that the sulfur atom of compound 5d formed a sulfur-π interaction with the amino acid residue His524 of the ERα LBD. These interactions play important roles for the binding affinity of compound 5d to the ERα LBD.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Antagonistas de Estrogênios/farmacologia , Moduladores de Receptor Estrogênico/farmacologia , Receptor alfa de Estrogênio/antagonistas & inibidores , Antineoplásicos/farmacologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Antagonistas de Estrogênios/síntese química , Moduladores de Receptor Estrogênico/síntese química , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Células MCF-7 , Relação Estrutura-Atividade , Enxofre/química
20.
Cell Chem Biol ; 26(12): 1692-1702.e5, 2019 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-31706983

RESUMO

Estrogen exerts extensive and diverse effects throughout the body of women. In addition to the classical nuclear estrogen receptors (ERα and ERß), the G protein-coupled estrogen receptor GPER is an important mediator of estrogen action. Existing ER-targeted therapeutic agents act as GPER agonists. Here, we report the identification of a small molecule, named AB-1, with the previously unidentified activity of high selectivity for binding classical ERs over GPER. AB-1 also possesses a unique functional activity profile as an agonist of transcriptional activity but an antagonist of rapid signaling through ERα. Our results define a class of small molecules that discriminate between the classical ERs and GPER, as well as between modes of signaling within the classical ERs. Such an activity profile, if developed into an ER antagonist, could represent an opportunity for the development of first-in-class nuclear hormone receptor-targeted therapeutics for breast cancer exhibiting reduced acquired and de novo resistance.


Assuntos
Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Ligantes , Transdução de Sinais , Animais , Proliferação de Células/efeitos dos fármacos , Estradiol/farmacologia , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor beta de Estrogênio/antagonistas & inibidores , Feminino , Proteína Forkhead Box O3/genética , Proteína Forkhead Box O3/metabolismo , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos C57BL , Ligação Proteica , Receptores Estrogênicos/genética , Receptores Estrogênicos/metabolismo , Receptores Acoplados a Proteínas-G/agonistas , Receptores Acoplados a Proteínas-G/genética , Receptores Acoplados a Proteínas-G/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transcrição Genética/efeitos dos fármacos , Útero/efeitos dos fármacos , Útero/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...