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1.
Bull Cancer ; 111(4): 356-362, 2024 Apr.
Artigo em Francês | MEDLINE | ID: mdl-38453587

RESUMO

INTRODUCTION: Evaluating the benefits and risks of prolonged hormonal treatment with aromatase inhibitors (AIs) for treating hormone-dependent breast cancer. METHODS: A systematic review and meta-analysis was conducted. Studies reporting on randomized clinical trials concerning prolongating hormonal therapy with AIs as compared to a placebo or no prolongation, after an initial five years of hormonal therapy, were eligible. RESULTS: Seven clinical trials were included. Prolonged AI therapy was associated with a statistically significant improvement in disease-free survival (RR=0.70, 95% CI 0.60 to 0.80). A statistically significant increase was observed for osteoporosis (RR=1.17, 95% CI 1.03 to 1.33), hot flushes/flashes (RR=1.27, 95% CI 1.08 to 1.49), myalgia (RR=1.23, 95% CI 1.09 to 1.39), fractures (RR=1.26, 95% CI 1.09 to 1.45) and arthralgia (RR=1.17, 95% CI 1.10 to 1.25). However, no statistically significant association was observed between prolonged AI therapy and overall survival, cardiovascular events, and bone pain. DISCUSSION: Prolonged AI therapy has significant benefits in terms of disease-free survival in women with hormone-dependent breast cancer. However, adverse effects and a lack of evidence for a benefit on overall survival must be considered in the decision-making process regarding adjuvant hormone therapy extension.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Neoplasias da Mama/tratamento farmacológico , Inibidores da Aromatase/efeitos adversos , Terapia Combinada , Quimioterapia Adjuvante/efeitos adversos , Adjuvantes Imunológicos/uso terapêutico , Hormônios/uso terapêutico , Antineoplásicos Hormonais/efeitos adversos , Tamoxifeno/efeitos adversos
2.
Protein Sci ; 33(4): e4940, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38511482

RESUMO

Estrogen receptor α is commonly used in synthetic biology to control the activity of genome editing tools. The activating ligands, estrogens, however, interfere with various cellular processes, thereby limiting the applicability of this receptor. Altering its ligand preference to chemicals of choice solves this hurdle but requires adaptation of unspecified ligand-interacting residues. Here, we provide a solution by combining rational protein design with multi-site-directed mutagenesis and directed evolution of stably integrated variants in Saccharomyces cerevisiae. This method yielded an estrogen receptor variant, named TERRA, that lost its estrogen responsiveness and became activated by tamoxifen, an anti-estrogenic drug used for breast cancer treatment. This tamoxifen preference of TERRA was maintained in mammalian cells and mice, even when fused to Cre recombinase, expanding the mammalian synthetic biology toolbox. Not only is our platform transferable to engineer ligand preference of any steroid receptor, it can also profile drug-resistance landscapes for steroid receptor-targeted therapies.


Assuntos
Estradiol , Receptor alfa de Estrogênio , Animais , Camundongos , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/química , Receptor alfa de Estrogênio/metabolismo , Estradiol/química , Estradiol/metabolismo , Ligantes , Tamoxifeno/farmacologia , Tamoxifeno/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/química , Receptores de Estrogênio/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Mamíferos
3.
J Nanobiotechnology ; 22(1): 122, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504208

RESUMO

Endocrine therapy is standard for hormone receptor-positive (HR+) breast cancer treatment. However, current strategies targeting estrogen signaling pay little attention to estradiol metabolism in the liver and is usually challenged by treatment failure. In a previous study, we demonstrated that the natural compound naringenin (NAR) inhibited HR+ breast cancer growth by activating estrogen sulfotransferase (EST) expression in the liver. Nevertheless, the poor water solubility, low bio-barrier permeability, and non-specific distribution limited its clinical application, particularly for oral administration. Here, a novel nano endocrine drug NAR-cell penetrating peptide-galactose nanoparticles (NCG) is reported. We demonstrated that NCG presented specific liver targeting and increased intestinal barrier permeability in both cell and zebrafish xenotransplantation models. Furthermore, NCG showed liver targeting and enterohepatic circulation in mouse breast cancer xenografts following oral administration. Notably, the cancer inhibition efficacy of NCG was superior to that of both NAR and the positive control tamoxifen, and was accompanied by increased hepatic EST expression and reduced estradiol levels in the liver, blood, and tumor tissue. Moreover, few side effects were observed after NCG treatment. Our findings reveal NCG as a promising candidate for endocrine therapy and highlight hepatic EST targeting as a novel therapeutic strategy for HR+ breast cancer.


Assuntos
Neoplasias da Mama , Flavanonas , Nanopartículas , Humanos , Camundongos , Animais , Feminino , Neoplasias da Mama/patologia , Peixe-Zebra/metabolismo , Receptores de Estrogênio/metabolismo , Estrogênios/metabolismo , Estrogênios/uso terapêutico , Tamoxifeno/farmacologia , Estradiol/farmacologia , Fígado/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-38460447

RESUMO

Human serum albumin (HSA) is known to undergo modifications by glucose during diabetes. This process produces glycated HSA that can have altered binding to some drugs. In this study, high-performance affinity microcolumns and competition studies were used to see how glycation affects the binding by two thiazolidinedione-class drugs (i.e., pioglitazone and rosiglitazone) at specific regions of HSA. These regions included Sudlow sites I and II, the tamoxifen and digitoxin sites, and a drug-binding site located in subdomain IB. At Sudlow site II, the association equilibrium constants (or binding constants) for pioglitazone and rosiglitazone with normal HSA were 1.7 × 105 M-1 and 2.0 × 105 M-1 at pH 7.4 and 37 °C, with values that changed by up to 5.7-fold for glycated HSA. Sudlow site I of normal HSA had binding constants for pioglitazone and rosiglitazone of 3.4 × 105 M-1 and 4.6 × 105 M-1, with these values changing by up to 1.5-fold for glycated HSA. Rosiglitazone was found to also bind a second region that had a positive allosteric effect on Sudlow site I for all the tested preparations of HSA (binding affinity, 1.1-3.2 × 105 M-1; coupling constant for Sudlow site I, 1.20-1.34). Both drugs had a strong positive allosteric effect on the tamoxifen site of HSA (coupling constants, 13.7-19.9 for pioglitazone and 3.7-11.5 for rosiglitazone). Rosiglitazone also had weak interactions at a site in subdomain IB, with a binding constant of 1.4 × 103 M-1 for normal HSA and a value that was altered by up to 6.8-fold with glycated HSA. Neither of the tested drugs had any significant binding at the digitoxin site. The results were used to produce affinity maps that described binding by these thiazolidinediones with HSA and the effects of glycation on these interactions during diabetes.


Assuntos
Diabetes Mellitus , Albumina Sérica Humana , Humanos , Albumina Sérica Humana/química , Hipoglicemiantes/química , Reação de Maillard , Rosiglitazona , Pioglitazona , Ligação Proteica , Albumina Sérica/química , Tamoxifeno , Digitoxina , Cromatografia de Afinidade/métodos , Sítios de Ligação
5.
Clin Transl Sci ; 17(3): e13761, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38476074

RESUMO

Tamoxifen, a selective estrogen receptor modulator, is used to treat hormone receptor-positive breast cancer. Tamoxifen acts as a prodrug, with its primary therapeutic effect mediated by its principal metabolite, endoxifen. However, tamoxifen has complex pharmacokinetics involving several drug-metabolizing enzymes and transporters influencing its disposition. Genes encoding enzymes involved in tamoxifen disposition exhibit genetic polymorphisms which vary widely across world populations. This review highlights the lack of data on tamoxifen pharmacogenetics among African populations. Gaps in data are described in this study with the purpose that future research can address this dearth of research on the pharmacogenetics of tamoxifen among African breast cancer patients. Initiatives such as the African Pharmacogenomics Network (APN) are crucial in promoting comprehensive pharmacogenetics studies to pinpoint important variants in pharmacogenes that could be used to reduce toxicity and improve efficacy.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Farmacogenética , Citocromo P-450 CYP2D6/genética , Tamoxifeno , Polimorfismo Genético
6.
J Ovarian Res ; 17(1): 66, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504307

RESUMO

BACKGROUND: Quiescin sulfhydryl oxidase 2 (QSOX2) is a flavin adenine dinucleotide-dependent sulfhydryl oxidase that is known to be involved in protein folding, cell growth regulation, and redox state modification through oxidative activities. Earlier studies demonstrated the tissue and cellular localization of QSOX2 in the male reproductive tract, as well as the highly-regulated mechanism of QSOX2 protein synthesis and expression through the coordinated action of testosterone and epididymal-enriched amino acid, glutamate. However, the presence and the functions of QSOX2 in female reproduction are unknown. In this study, we applied the Cre-loxP gene manipulation system to generate the heterozygous and homozygous Qsox2 knockout mice and examined its effects on ovarian function. RESULTS: We demonstrated that QSOX2 was detected in the follicle-supporting cells (granulosa and cumulus cells) of ovarian follicles of all stages but was absent in the corpus luteum, suggesting its supportive role in folliculogenesis. In comparison with reproductive organogenesis in wild-type mice, there was no difference in testicular and epididymal structure in male Qsox2 knockout; however, Qsox2 knockout disrupted the regular ovulation process in female mice as a drastic decrease in the formation of the corpus luteum was detected, and no pregnancy was achieved when mating males with homozygous Qsox2 knockout females. RNAseq analyses further revealed that Qsox2 knockout altered critical signaling pathways and genes that are responsible for maintaining ovarian functions. CONCLUSION: Our data demonstrated for the first time that Qsox2 is critical for ovarian function in mice.


Assuntos
Células da Granulosa , Oxirredutases , Tamoxifeno , Feminino , Camundongos , Masculino , Animais , Células da Granulosa/metabolismo , Tamoxifeno/farmacologia , Tamoxifeno/metabolismo , Ovário , Ovulação , Camundongos Knockout
7.
JAMA Netw Open ; 7(3): e242082, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38477918

RESUMO

Importance: Few oncology studies have assessed the effectiveness of adjuvant ovarian function suppression (OFS) in observational settings for premenopausal hormone receptor-positive breast cancer. Target trial emulation is increasingly used for estimating treatment outcomes in observational cohorts. Objectives: To describe hormone therapy and OFS treatment patterns (aim 1), examine the association between adding OFS to tamoxifen (TAM) or aromatase inhibitor (AI) and survival (aim 2), and examine the association between duration of hormone treatment (TAM or AI) plus OFS (H-OFS) and survival (aim 3). Design, Setting, and Participants: This population-based cohort study included all premenopausal, early-stage breast cancer diagnoses between 2010 and 2020 in Alberta, Canada. Target trial emulation was conducted. Eligibility criteria were directly modeled after the Suppression of Ovarian Function Trial (SOFT) and Tamoxifen and Exemestane Trial (TEXT). Participants were followed up for a maximum of 5 years. Data were analyzed from July 2022 through March 2023. Exposures: For aim 2, exposures were receiving the following baseline treatments for 2 years: AI + OFS (AI-OFS), TAM + OFS (T-OFS), and TAM alone. For aim 3, exposures were a 2-year or greater and a less than 2-year duration of H-OFS. Main Outcomes and Measures: Recurrence-free survival was the primary outcome of interest. Marginal structural Cox models with inverse probability treatment and censoring weights were used to estimate hazard ratios (HRs), adjusted for baseline and time-varying confounding variables. Results: Among 3434 female patients with premenopausal, early-stage breast cancer diagnoses (median [IQR] age, 45 [40-48] years), 2647 individuals satisfied SOFT and TEXT eligibility criteria. There were 2260 patients who initiated TAM, 232 patients who initiated T-OFS, and 155 patients who initiated AI-OFS; 192 patients received H-OFS for 2 or more years, and 195 patients received H-OFS for less than 2 years. The 5-year recurrence risks were not significantly lower in AI-OFS vs TAM (HR, 0.76; 95% CI, 0.38-1.33) or T-OFS vs TAM (HR, 0.87; 95% CI, 0.50-1.45) groups. Patients receiving H-OFS for 2 or more years had significantly better 5-year recurrence-free survival compared with those receiving H-OFS for less than 2 years (HR, 0.69; 95% CI, 0.54-0.90). Conclusions and Relevance: This study found no significant reductions in recurrence risk for AI-OFS and T-OFS compared with TAM alone. H-OFS duration for at least 2 years was associated with significantly improved recurrence-free survival.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Pessoa de Meia-Idade , Estudos de Coortes , Adjuvantes Imunológicos , Tamoxifeno , Alberta , Inibidores da Aromatase , Hormônios
8.
Front Endocrinol (Lausanne) ; 15: 1254213, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481446

RESUMO

The role of simultaneous neoadjuvant endocrine therapy in chemotherapy in HR+HER2- breast cancer continues to be controversial. This systematic review and meta-analysis was conducted to further evaluate the effectiveness and safety of this strategy for HR+HER2- breast cancer patients. Trials in which HR+HER2- breast cancer patients were randomly assigned to either single or simultaneous endocrine-assisted neoadjuvant chemotherapy were eligible for inclusion. The prime endpoint was the pathological complete response (pCR) rate. The clinical response (complete clinical response: CR, partial response: PR) and safety were secondary endpoints. A random effect model was used for statistical analysis. A total of 690 patients from five trials were included. PCR rate was 10.43% in the concomitant endocrine group and 7.83% in control group (OR=1.37, 95%CI 0.72-2.60, P=0.34). The CR rate was 15.50% for the concomitant endocrine group and 10.26% for the control group. (OR=1.61, 95%CI 0.99-2.61, P=0.05). ORR (CR+PR) was significantly higher in the simultaneous endocrine group compared to the control group (79.53% (272/342) vs. 70.09% (239/341) , OR=1.70, 95%CI 1.19-2.43, P=0.004) and the meta-analysis approach showed no heterogeneity (I2 = 0%, P=0.54) . Tamoxifen concurrent with chemotherapy could increase the frequency of adverse events, whereas aromatase inhibitors (AIs) would not. Our findings provide evidence for the efficacy and safety of concurrent neoadjuvant endocrine therapy (AIs) with chemotherapy as an available option to achieve a higher clinical response rate for HR+HER2- breast cancer patients compared with chemotherapy alone with low toxicity. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022340725.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Terapia Neoadjuvante , Tamoxifeno/uso terapêutico , Terapia Combinada , Inibidores da Aromatase/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
Biol Direct ; 19(1): 21, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459605

RESUMO

BACKGROUND: Mammalian enabled (MENA) protein is a member of the enabled/vasodilator stimulated phosphoprotein (Ena/VASP) protein family, which regulates cytoplasmic actin network assembly. It plays a significant role in breast cancer invasion, migration, and resistance against targeted therapy and chemotherapy. However, its role in the efficacy of endocrine therapy for the hormone receptor-positive (HR+) breast cancer patients is not known. This study investigated the role of MENA in the resistance against tamoxifen therapy in patients with HR+ breast cancer and the underlying mechanisms. METHODS: MENA expression levels in the clinical HR+ breast cancer samples (n = 119) were estimated using immunohistochemistry (IHC) to determine its association with the clinicopathological features, tamoxifen resistance, and survival outcomes. Western blotting (WB) and quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) analysis was performed to estimate the MENA protein and mRNA levels in the tamoxifen-sensitive and -resistant HR+ breast cancer cell lines. Furthermore, CCK8, colony formation, and the transwell invasion and migration assays were used to analyze the effects of MENA knockdown on the biological behavior and tamoxifen sensitivity of the HR+ breast cancer cell lines. Xenograft tumor experiments were performed in the nude mice to determine the tumor growth rates and tamoxifen sensitivity of the control and MENA knockdown HR+ breast cancer cells in the presence and absence of tamoxifen treatment. Furthermore, we estimated the growth rates of organoids derived from the HR+ breast cancer patients (n = 10) with high and low MENA expression levels when treated with tamoxifen. RESULTS: HR+ breast cancer patients with low MENA expression demonstrated tamoxifen resistance and poorer prognosis compared to those with high MENA expression. Univariate and multivariate Cox regression analysis demonstrated that MENA expression was an independent predictor of tamoxifen resistance in patients with HR+ breast cancer. MENA knockdown HR+ breast cancer cells showed significantly reduced tamoxifen sensitivity in the in vitro experiments and the in vivo xenograft tumor mouse model compared with the corresponding controls. Furthermore, MENA knockdown increased the in vitro invasion and migration of the HR+ breast cancer cells. HR+ breast cancer organoids with low MENA expression demonstrated reduced tamoxifen sensitivity than those with higher MENA expression. Mechanistically, P-AKT levels were significantly upregulated in the MENA-knockdown HR + breast cancer cells treated with or without 4-OHT compared with the corresponding controls. CONCLUSIONS: This study demonstrated that downregulation of MENA promoted tamoxifen resistance in the HR+ breast cancer tissues and cells by enhancing the AKT signaling pathway. Therefore, MENA is a promising prediction biomarker for determining tamoxifen sensitivity in patients with HR+ breast cancer.


Assuntos
Neoplasias da Mama , Animais , Feminino , Humanos , Camundongos , Antineoplásicos Hormonais/farmacologia , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Mamíferos/metabolismo , Camundongos Nus , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico
10.
Biotechnol J ; 19(2): e2300560, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38403459

RESUMO

Tamoxifen (TAM) resistance is finally developed in over 40% of patients with estrogen receptor α-positive breast cancer (ERα+ -BC), documenting that discovering new molecular subtype is needed to confer perception to the heterogeneity of ERα+ -BC. We obtained representative gene sets subtyping ERα+ -BC using gene set variation analysis (GSVA), non-negative matrix factorization (NMF), and COX regression methods on the basis of METABRIC, TCGA, and GEO databases. Furthermore, the risk score of ERα+ -BC subtyping was established using least absolute shrinkage and selection operator (LASSO) regression on the basis of genes in the representative gene sets, thereby generating the two subtypes of ERα+ -BC. We further found that minichromosome maintenance complex component 2 (MCM2) functioned as the hub gene subtyping ERα+ -BC using GO, KEGG, and MCODE. MCM2 expression was capable for specifically predicting 1-year overall survival (OS) of ERα+ -BC and correlated with T stage, AJCC stage, and tamoxifen (TAM) sensitivity of ERα+ -BC. The downregulation of MCM2 expression inhibited proliferation, migration, and invasion of TAM-resistant cells and promoted G0/G1 arrest. Altogether, tamoxifen resistance entails that MCM2 is a hub gene subtyping ERα+ -BC, providing a novel dimension for discovering a potential target of TAM-resistant BC.


Assuntos
Neoplasias da Mama , Tamoxifeno , Humanos , Feminino , Tamoxifeno/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Componente 2 do Complexo de Manutenção de Minicromossomo/genética , Componente 2 do Complexo de Manutenção de Minicromossomo/metabolismo , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Células MCF-7
11.
Invest Ophthalmol Vis Sci ; 65(2): 32, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38386333

RESUMO

Purpose: Animal models of ocular hypertension (OH) have been developed to understand the pathogenesis of glaucoma and facilitate drug discovery. However, many of these models are fraught with issues, including severe intraocular inflammation and technical challenges. Lysophosphatidic acid (LPA) is implicated in trabecular meshwork fibrosis and increased resistance of aqueous outflow, factors that contribute to high intraocular pressure (IOP) in human open-angle glaucoma. We aimed to elevate IOP by increasing expression of the LPA-producing enzyme autotaxin (ATX) in mouse eyes. Methods: Tamoxifen-inducible ATX transgenic mice were developed. Tamoxifen was administered to six- to eight-week-old mice via eye drops to achieve ATX overexpression in the eye. IOP and retinal thickness were measured over time, and retinal flat-mount were evaluated to count retinal ganglion cells (RGCs) loss after three months. Results: Persistent elevation of ATX expression in mouse eyes was confirmed through immunohistochemistry and LysoPLD activity measurement. ATX Tg mice exhibited significantly increased IOP for nearly two months following tamoxifen treatment, with no anterior segment changes or inflammation. Immunohistochemical analysis revealed enhanced expression of extracellular matrix near the angle after two weeks and three months of ATX induction. This correlated with reduced outflow facility, indicating that sustained ATX overexpression induces angle fibrosis, elevating IOP. Although inner retinal layer thickness remained stable, peripheral retina showed a notable reduction in RGC cell count. Conclusions: These findings confirm the successful creation of an open-angle OH mouse model, in which ATX expression in the eye prompts fibrosis near the angle and maintains elevated IOP over extended periods.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Hipertensão Ocular , Humanos , Animais , Camundongos , Modelos Animais de Doenças , Biomarcadores , Inflamação , Fibrose , Tamoxifeno
12.
World J Surg Oncol ; 22(1): 60, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383372

RESUMO

BACKGROUND: Radiation therapy is often indicated as part of the treatment for breast cancer and is therefore used frequently worldwide. Vasculopathy is a general term used to describe any condition that affects blood vessels. We present a case report of a patient who presented with vasculopathy as a rare late side effect of radiation therapy to the breast. CASE PRESENTATION: This 66-year-old woman was initially treated with breast-conserving surgery for early-stage receptor-positive left breast carcinoma. She received postoperative radiation therapy and hormonal treatment with tamoxifen. She developed sudden spontaneous painless ecchymosis spread over the whole irradiated area 1.5 years after finishing her radiation therapy. Tumor relapse was excluded. There was no associated vasculitis. The cause was presumed to be multifactorial. She had a history of smoking and was known to have hyperlipidemia. She had undergone several surgical treatments at the left breast one year after her initial breast-conserving treatment and was taking tamoxifen. Anti-inflammatory medicine and treatments increasing local blood flow were prescribed. The ecchymosis resolved completely within one month. CONCLUSIONS: Vasculopathy can occur as a rare late side effect of radiation therapy. It can be reversible. Prevention begins with carefully treating precipitating factors.


Assuntos
Neoplasias da Mama , Doenças Vasculares , Humanos , Feminino , Idoso , Equimose/tratamento farmacológico , Equimose/cirurgia , Recidiva Local de Neoplasia/cirurgia , Neoplasias da Mama/patologia , Tamoxifeno/uso terapêutico , Mastectomia Segmentar , Doenças Vasculares/cirurgia
13.
Nat Commun ; 15(1): 1689, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402222

RESUMO

Point-of-care sensors, which are low-cost and user-friendly, play a crucial role in precision medicine by providing quick results for individuals. Here, we transform the conventional glucometer into a 4-hydroxytamoxifen therapeutic biosensor in which 4-hydroxytamoxifen modulates the electrical signal generated by glucose oxidation. To encode the 4-hydroxytamoxifen signal within glucose oxidation, we introduce the ligand-binding domain of estrogen receptor-alpha into pyrroloquinoline quinone-dependent glucose dehydrogenase by constructing and screening a comprehensive protein insertion library. In addition to obtaining 4-hydroxytamoxifen regulatable engineered proteins, these results unveil the significance of both secondary and quaternary protein structures in propagation of conformational signals. By constructing an effective bioelectrochemical interface, we detect 4-hydroxytamoxifen in human blood samples as changes in the electrical signal and use this to develop an electrochemical algorithm to decode the 4-hydroxytamoxifen signal from glucose. To meet the miniaturization and signal amplification requirements for point-of-care use, we harness power from glucose oxidation to create a self-powered sensor. We also amplify the 4-hydroxytamoxifen signal using an organic electrochemical transistor, resulting in milliampere-level signals. Our work demonstrates a broad interdisciplinary approach to create a biosensor that capitalizes on recent innovations in protein engineering, electrochemical sensing, and electrical engineering.


Assuntos
Técnicas Biossensoriais , Sistemas Automatizados de Assistência Junto ao Leito , Tamoxifeno/análogos & derivados , Humanos , Glucose , Técnicas Biossensoriais/métodos , Engenharia de Proteínas , Técnicas Eletroquímicas
14.
Cell Death Dis ; 15(2): 147, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360722

RESUMO

Tamoxifen (TAM) is the frontline therapy for estrogen receptor-positive (ER+) breast cancer in premenopausal women that interrupts ER signaling. As tumors with elevated heterogeneity, amounts of ER-negative (ER-) cells are present in ER+ breast cancer that cannot be directly killed by TAM. Despite complete remissions have been achieved in clinical practice, the mechanism underlying the elimination of ER- cells during TAM treatment remains an open issue. Herein, we deciphered the elimination of ER- cells in TAM treatment from the perspective of the bystander effect. Markable reductions were observed in tumorigenesis of ER- breast cancer cells by applying both supernatants from TAM-treated ER+ cells and a transwell co-culture system, validating the presence of a TAM-induced bystander effect. The major antitumor protein derived from ER+ cells, peptidyl-prolyl cis-trans isomerase B (PPIB), is the mediator of the TAM-induced bystander effect identified by quantitative proteomics. The attenuation of ER- cells was attributed to activated BiP/eIF2α/CHOP axis and promoted endoplasmic reticulum stress (ERS)-induced apoptosis, which can also be triggered by PPIB independently. Altogether, our study revealed a novel TAM-induced bystander effect in TAM treatment of ER+ breast cancer, raising the possibility of developing PPIB as a synergistic antitumor agent or even substitute endocrine therapy.


Assuntos
Neoplasias da Mama , Efeito Espectador , Peptidilprolil Isomerase , Tamoxifeno , Feminino , Humanos , Antineoplásicos Hormonais/farmacologia , Apoptose , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Isoenzimas , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico
15.
Front Biosci (Landmark Ed) ; 29(2): 81, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38420813

RESUMO

BACKGROUND: Previous clinical studies have suggested that Toll-like receptor (TLR)2 had predictive function for endocrine resistance in HER2-positive breast cancer (BCa). Nevertheless, it remains unclear whether TLR2 would relate to development of endocrine therapy resistance in triple-positive breast cancer (TPBC). METHODS: Bioinformatic analysis of TLR2 was carried out through a database. Ten tumor tissues were obtained from TPBC patients who underwent surgery, with five patients displaying primary resistance to tamoxifen (TAM) with the remaining 5 being sensitive. Different levels of proteins were identified through mass spectrometry analysis and confirmed through reverse transcription polymerase chain reaction (RT-PCR) and western blot. TAM-resistant cell lines (BT474-TAM) were established by continuous exposure to TAM, and TAM resistance was assessed via IC50. Additionally, TLR2 mRNA was analyzed through western blot and RT-PCR in BT474, BT474-TAM, MCF-7, and MCF10A cells. Furthermore, TLR2-specific interference sequences were utilized to downregulate TLR2 expression in BT474-TAM cells to elucidate its role in TAM resistance. RESULTS: TLR2 had a correlation with decreased relapse-free survival in BCa patients from the GSE1456-GPL96 cohort, and it was involved in cancer development predominantly mediated by MAPK and PI3K pathways. TLR2 protein expression ranked in the top 5 proteins within the TAM-resistant group, and was 1.9 times greater than that in the sensitive group. Additionally, TLR2 mRNA and protein expression increased significantly in the established TAM-resistant BT474/TAM cell lines. The sensitivity of TAM was restored upon TLR2 downregulation in BT474/TAM cells. CONCLUSIONS: TLR2 might have a therapeutic value as it was involved in the TAM resistance in TPBC, with potential to be a marker for primary endocrine resistance.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Receptor 2 Toll-Like/uso terapêutico , Antineoplásicos Hormonais/farmacologia , Antineoplásicos Hormonais/uso terapêutico , Fosfatidilinositol 3-Quinases/metabolismo , Linhagem Celular Tumoral , Transdução de Sinais , Proliferação de Células , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/genética , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico , RNA Mensageiro/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica
16.
Breast Cancer Res ; 26(1): 33, 2024 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409088

RESUMO

INTRODUCTION: Estrogen receptor (ER) positive patients compromise about 70% of breast cancers. Tamoxifen, an antagonist of ERα66 (the classic ER), is the most effective and the standard first-line drug. However, its efficacy is limited by the development of acquired resistance. METHODS: A specific inhibitor of Hsp70-Bim protein-protein interaction (PPI), S1g-2, together with an inhibitor of Hsp70-Bag3 PPI, MKT-077 and an ATP-competitive inhibitor VER155008, were used as chemical tools. Cell viability assays, co-immunoprecipitation and gene knockdown were used to investigate the role of Hsp70 in tamoxifen resistance. A xenograft model was established in which tamoxifen-resistant breast cancer (MCF-7/TAM-R) cells maintained in the presence of 5 µM tamoxifen were subcutaneously inoculated. The anti-tumor efficiency of S1g-2 was measured after a daily injection of 0.8 mg/kg for 14 days. RESULTS: It was revealed that Hsp70-Bim PPI protects ERα-positive breast cancer from tamoxifen-induced apoptosis through binding and stabilizing ERα36, rather than ERα66, resulting in sustained EGFR mRNA and protein expression. Disruption of Hsp70-Bim PPI and downregulation of ERα36 expression in tumor samples are consistent with the in vitro functions of S1g-2, resulting in about a three-fold reduction in tumor volume. CONCLUSIONS: The in vivo activity and safety of S1g-2 illustrated that it is a potential strategy for Hsp70-Bim disruption to overcome tamoxifen-resistant ER-positive breast cancer.


Assuntos
Neoplasias da Mama , Tamoxifeno , Humanos , Feminino , Tamoxifeno/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Proteína 11 Semelhante a Bcl-2/genética , Proteína 11 Semelhante a Bcl-2/metabolismo , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Regulação Neoplásica da Expressão Gênica
17.
PLoS One ; 19(2): e0297080, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38408073

RESUMO

BACKGROUND: Hair loss/thinning is a common side effect of tamoxifen in estrogen receptor (ER) positive breast cancer therapy. Some nutraceuticals known to promote hair growth are avoided during breast cancer therapy for fear of phytoestrogenic activity. However, not all botanical ingredients have similarities to estrogens, and in fact, no information exists as to the true interaction of these ingredients with tamoxifen. Therefore, this study sought to ascertain the effect of nutraceuticals (+/- estrogen/tamoxifen), on proliferation of breast cancer cells and the relative expression of ERα/ß. METHODS: Kelp, Astaxanthin, Saw Palmetto, Tocotrienols, Maca, Horsetail, Resveratrol, Curcumin and Ashwagandha were assessed on proliferation of MCF7, T47D and BT483 breast cancer cell lines +/- 17ß-estradiol and tamoxifen. Each extract was analysed by high performance liquid chromatography (HPLC) prior to use. Cellular ERα and ERß expression was assessed by qRT-PCR and western blot. Changes in the cellular localisation of ERα:ERß and their ratio following incubation with the nutraceuticals was confirmed by immunocytochemistry. RESULTS: Estradiol stimulated DNA synthesis in three different breast cancer cell lines: MCF7, T47D and BT483, which was inhibited by tamoxifen; this was mirrored by a specific ERa agonist in T47D and BT483 cells. Overall, nutraceuticals did not interfere with tamoxifen inhibition of estrogen; some even induced further inhibition when combined with tamoxifen. The ERα:ERß ratio was higher at mRNA and protein level in all cell lines. However, incubation with nutraceuticals induced a shift to higher ERß expression and a localization of ERs around the nuclear periphery. CONCLUSIONS: As ERα is the key driver of estrogen-dependent breast cancer, if nutraceuticals have a higher affinity for ERß they may offer a protective effect, particularly if they synergize and augment the actions of tamoxifen. Since ERß is the predominant ER in the hair follicle, further studies confirming whether nutraceuticals can shift the ratio towards ERß in hair follicle cells would support a role for them in hair growth. Although more research is needed to assess safety and efficacy, this promising data suggests the potential of nutraceuticals as adjuvant therapy for hair loss in breast cancer patients receiving endocrine therapy.


Assuntos
Neoplasias da Mama , Tamoxifeno , Humanos , Feminino , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico , Neoplasias da Mama/genética , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Estradiol/farmacologia , Estrogênios/farmacologia , Células MCF-7 , Suplementos Nutricionais , Alopecia/tratamento farmacológico , Cabelo/metabolismo , Linhagem Celular Tumoral , Proliferação de Células
18.
Mol Biol Rep ; 51(1): 241, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300337

RESUMO

BACKGROUND: A growing number of studies has indicated that the expression of Breast Cancer Susceptibility Genes 1 (BRCA1) and BRCA2 contribute to the resistance to DNA-damaging chemotherapies. Tamoxifen induces tumor cell death by suppressing estrogen receptor (ER) signaling and inducing DNA damage, and BRCA1 upregulation causes Tamoxifen chemoresistance in breast cancer cells. Consequently, this research study aimed to investigate the possible therapeutic effect of Human Umbilical Cord Mesenchymal Stem Cells Conditioned Medium (UCMSCs-CM) on sensitizing breast cancer cells to Tamoxifen by regulating BRCA1 and BRCA2 expression in vivo. METHODS: Forty female mice, 4-8 weeks old, with weight of 150 g, were used for this study. Mouse 4T1 breast tumor models were established and then treated with UCMSCs-CM and Tamoxifen alone or in combination. After 10 days, the tumor masses were collected and the expression levels of BRCA1 and BRCA2 were evaluated using qRT-PCR assay. RESULTS: The results obtained from qRT-PCR assay illustrated that UCMSCs-CM, either alone or in combination with Tamoxifen, significantly downregulated the mRNA expression levels of BRCA1 in breast cancer mouse models. However, both UCMSCs-CM and Tamoxifen indicated no statistically significant impact on BRCA2 mRNA expression compared to controls. CONCLUSION: Our findings evidenced that UCMSCs-CM could be considered as a potential therapeutic option to modulate Tamoxifen chemosensitivity by regulating BRCA1 in breast cancer.


Assuntos
Neoplasias da Mama , Células-Tronco Mesenquimais , Humanos , Feminino , Animais , Camundongos , Meios de Cultivo Condicionados/farmacologia , Tamoxifeno/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Modelos Animais de Doenças , RNA Mensageiro , Proteína BRCA1/genética , Proteína BRCA2/genética
19.
Anticancer Drugs ; 35(4): 371-376, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38241197

RESUMO

To investigate the effects of tamoxifen (TAM) and toremifene (TOR) on hepatic function and serum lipid levels in breast cancer patients receiving adjuvant endocrine therapy. The clinical data of 597 early breast cancer patients treated at the First Affiliated Hospital of Nanjing Medical University between January 2016 and December 2022 were collected. All the patients received standard adjuvant endocrine therapy with TAM or TOR after chemotherapy. Hepatic function and serum lipid data of all patients before and at 6 months and 1, 2, and 3 years after the treatment were collected retrospectively and analyzed statistically. There: no negative effect on hepatic function was observed in patients treated with either TAM or TOR. The triglyceride levels in both groups increased during treatment, and the effect of TAM on improving total cholesterol levels was stronger. Total cholesterol levels were not affected by time or treatment regimen. The low-density lipoprotein cholesterol levels decreased in both groups, and the effect was similar between groups. TAM can decrease the high-density lipoprotein cholesterol levels, whereas TOR can increase the high-density lipoprotein cholesterol levels, and there was a significant difference between groups. In the postoperative adjuvant endocrine therapy, TOR and TAM will not negatively impact the hepatic function of breast cancer patients, and TOR is better than TAM in the management of serum lipids; therefore, it may be a better choice for clinical medication.


Assuntos
Neoplasias da Mama , Toremifeno , Humanos , Feminino , Toremifeno/uso terapêutico , Toremifeno/farmacologia , Tamoxifeno/farmacologia , Estudos Retrospectivos , Antineoplásicos Hormonais/efeitos adversos , Quimioterapia Adjuvante , Adjuvantes Imunológicos , Lipídeos/uso terapêutico , Colesterol , Lipoproteínas HDL/uso terapêutico
20.
Circ Genom Precis Med ; 17(1): e004305, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38288614

RESUMO

BACKGROUND: Pathogenic variants in PKP2 (plakophilin-2) cause arrhythmogenic right ventricular cardiomyopathy, a disease characterized by life-threatening arrhythmias and progressive cardiomyopathy leading to heart failure. No effective medical therapy is available to prevent or arrest the disease. We tested the hypothesis that adeno-associated virus vector-mediated delivery of the human PKP2 gene to an adult mammalian heart deficient in PKP2 can arrest disease progression and significantly prolong survival. METHODS: Experiments were performed using a PKP2-cKO (cardiac-specific, tamoxifen-activated PKP2 knockout murine model). The potential therapeutic, adeno-associated virus vector of serotype rh.74 (AAVrh.74)-PKP2a (PKP2 variant A; RP-A601) is a recombinant AAVrh.74 gene therapy viral vector encoding the human PKP2 variant A. AAVrh.74-PKP2a was delivered to adult mice by a single tail vein injection either before or after tamoxifen-activated PKP2-cKO. PKP2 expression was confirmed by molecular and histopathologic analyses. Cardiac function and disease progression were monitored by survival analyses, echocardiography, and electrocardiography. RESULTS: Consistent with prior findings, loss of PKP2 expression caused 100% mortality within 50 days after tamoxifen injection. In contrast, AAVrh.74-PKP2a-mediated PKP2a expression resulted in 100% survival for >5 months (at study termination). Echocardiographic analysis revealed that AAVrh.74-PKP2a prevented right ventricle dilation, arrested left ventricle functional decline, and mitigated arrhythmia burden. Molecular and histological analyses showed AAVrh.74-PKP2a-mediated transgene mRNA and protein expression and appropriate PKP2 localization at the cardiomyocyte intercalated disc. Importantly, the therapeutic benefit was shown in mice receiving AAVrh.74-PKP2a after disease onset. CONCLUSIONS: These preclinical data demonstrate the potential for AAVrh.74-PKP2a (RP-A601) as a therapeutic for PKP2-related arrhythmogenic right ventricular cardiomyopathy in both early and more advanced stages of the disease.


Assuntos
Displasia Arritmogênica Ventricular Direita , Adulto , Humanos , Camundongos , Animais , Displasia Arritmogênica Ventricular Direita/genética , Displasia Arritmogênica Ventricular Direita/terapia , Displasia Arritmogênica Ventricular Direita/metabolismo , Placofilinas/genética , Miócitos Cardíacos/metabolismo , Arritmias Cardíacas/genética , Arritmias Cardíacas/terapia , Arritmias Cardíacas/metabolismo , Tamoxifeno/metabolismo , Progressão da Doença , Mamíferos/metabolismo
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