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1.
Circ Res ; 131(7): 620-636, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36052698

RESUMO

BACKGROUND: Heart failure is the leading cause of mortality, morbidity, and health care expenditures worldwide. Numerous studies have implicated GSK-3 (glycogen synthase kinase-3) as a promising therapeutic target for cardiovascular diseases. GSK-3 isoforms seem to play overlapping, unique and even opposing functions in the heart. Previously, we have shown that of the 2 isoforms of GSK-3, cardiac fibroblast GSK-3ß acts as a negative regulator of myocardial fibrosis in the ischemic heart. However, the role of cardiac fibroblast-GSK-3α in the pathogenesis of cardiac diseases is completely unknown. METHODS: To define the role of cardiac fibroblast-GSK-3α in myocardial fibrosis and heart failure, GSK-3α was deleted from fibroblasts or myofibroblasts with tamoxifen-inducible Tcf21- or Postn-promoter-driven Cre recombinase. Control and GSK-3α KO mice were subjected to cardiac injury and heart parameters were evaluated. The fibroblast kinome mapping was carried out to delineate molecular mechanism followed by in vivo and in vitro analysis. RESULTS: Fibroblast-specific GSK-3α deletion restricted fibrotic remodeling and preserved function of the injured heart. We observed reductions in cell migration, collagen gel contraction, α-SMA protein levels, and expression of ECM genes in TGFß1-treated KO fibroblasts, indicating that GSK-3α is required for myofibroblast transformation. Surprisingly, GSK-3α deletion did not affect SMAD3 activation, suggesting the profibrotic role of GSK-3α is SMAD3 independent. The molecular studies confirmed decreased ERK signaling in GSK-3α-KO CFs. Conversely, adenovirus-mediated expression of a constitutively active form of GSK-3α (Ad-GSK-3αS21A) in fibroblasts increased ERK activation and expression of fibrogenic proteins. Importantly, this effect was abolished by ERK inhibition. CONCLUSIONS: GSK-3α-mediated MEK-ERK activation is a critical profibrotic signaling circuit in the injured heart, which operates independently of the canonical TGF-ß1-SMAD3 pathway. Therefore, strategies to inhibit the GSK-3α-MEK-ERK signaling circuit could prevent adverse fibrosis in diseased hearts.


Assuntos
Cardiomiopatias , Insuficiência Cardíaca , Animais , Cardiomiopatias/metabolismo , Colágeno/metabolismo , Fibroblastos/metabolismo , Fibrose , Quinase 3 da Glicogênio Sintase/metabolismo , Quinase 3 da Glicogênio Sintase/farmacologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Insuficiência Cardíaca/metabolismo , Sistema de Sinalização das MAP Quinases , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/farmacologia , Miofibroblastos/metabolismo , Tamoxifeno/farmacologia , Fator de Crescimento Transformador beta1/metabolismo
2.
Sci Transl Med ; 14(663): eabo5959, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36130016

RESUMO

ESR1 (estrogen receptor 1) hotspot mutations are major contributors to therapeutic resistance in estrogen receptor-positive (ER+) breast cancer. Such mutations confer estrogen independence to ERα, providing a selective advantage in the presence of estrogen-depleting aromatase inhibitors. In addition, ESR1 mutations reduce the potency of tamoxifen and fulvestrant, therapies that bind ERα directly. These limitations, together with additional liabilities, inspired the development of the next generation of ERα-targeted therapeutics, of which giredestrant is a high-potential candidate. Here, we generated Esr1 mutant-expressing mammary gland models and leveraged patient-derived xenografts (PDXs) to investigate the biological properties of the ESR1 mutations and their sensitivity to giredestrant in vivo. In the mouse mammary gland, Esr1 mutations promote hypersensitivity to progesterone, triggering pregnancy-like tissue remodeling and profoundly elevated proliferation. These effects were driven by an altered progesterone transcriptional response and underpinned by gained sites of ERα-PR (progesterone receptor) cobinding at the promoter regions of pro-proliferation genes. PDX experiments showed that the mutant ERα-PR proliferative program is also relevant in human cancer cells. Giredestrant suppressed the mutant ERα-PR proliferation in the mammary gland more so than the standard-of-care agents, tamoxifen and fulvestrant. Giredestrant was also efficacious against the progesterone-stimulated growth of ESR1 mutant PDX models. In addition, giredestrant demonstrated activity against a molecularly characterized ESR1 mutant tumor from a patient enrolled in a phase 1 clinical trial. Together, these data suggest that mutant ERα can collaborate with PR to drive protumorigenic proliferation but remain sensitive to inhibition by giredestrant.


Assuntos
Neoplasias da Mama , Receptor alfa de Estrogênio , Animais , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carbolinas , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Estrogênios , Feminino , Fulvestranto/farmacologia , Fulvestranto/uso terapêutico , Humanos , Camundongos , Mutação/genética , Progesterona/farmacologia , Receptores de Estrogênio/genética , Receptores de Progesterona/genética , Receptores de Progesterona/uso terapêutico , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico
3.
Biochem Biophys Res Commun ; 627: 200-206, 2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36049358

RESUMO

Breast cancer is a prevalent female malignancy and tamoxifen remains the first-line treatment for breast cancer, but tamoxifen resistance is a frequent clinical problem. Circular RNAs (circRNAs) are a bunch of noncoding RNAs with circular structures and play crucial roles in cancer development. Here, we aimed to explore the unreported function of circMET in the modulation of tamoxifen resistance of breast cancer cells. The expression of circMET was upregulated in tamoxifen-resistant breast cancer cells. The depletion of circMET significantly reduced the cell viability and proliferation in tamoxifen-resistant breast cancer cells and the co-treatment of tamoxifen promoted the effect. Mechanically, the luciferase activity of circMET and was repressed by miR-204-5p and AHR 3'UTR in the cells. The expression of miR-204-5p was elevated by circMET knockdown. The expression of AHR was downregulated by miR-204-5p or circMET depletion, while the miR-204-5p inhibitor reversed the effect of circMET depletion in cells. The overexpression of circMET enhanced the cell viability and proliferation of MCF7-Re and T47D-Re cells but miR-204-5p or AHR depletion blocked the phenotype. Clinically, the expression of circMET and AHR has enhanced in tamoxifen-resistant samples compared with tamoxifen sensitive samples, but miR-204-5p presented a revered expression in the samples. Consequently, we concluded that circular RNA circMET contributed to tamoxifen resistance of breast cancer cells by targeting miR-204-5p/AHR signaling.


Assuntos
MicroRNAs , Neoplasias , Animais , Linhagem Celular Tumoral , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias/genética , RNA Circular/genética , Tamoxifeno/farmacologia
4.
Cells ; 11(17)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36078139

RESUMO

Breast carcinoma is one of the most common malignant tumors in women. In cases of hormone-sensitive cells, tamoxifen as an anti-estrogenic substance is a first line medication in the adjuvant setting. The spectrum of autologous breast reconstructions ranges from fat infiltrations to complex microsurgical procedures. The influence of adipose-derived stem cells (ASC) on the tumor bed and a possibly increased recurrence rate as a result are critically discussed. In addition, there is currently no conclusive recommendation regarding tamoxifen-treated patients and autologous fat infiltrations. The aim of the present study was to investigate the effect of tamoxifen on the gene expression of a variety of genes involved in tumorigenesis, cell growth and transformation. Mammary epithelial cell line and mammary carcinoma cell lines were treated with tamoxifen in vitro as well as co-cultured with ASC. Gene expression was quantified by PCR arrays and showed increased expression in the mammary carcinoma cell lines with increasing time of treatment and concentration of tamoxifen. The data presented can be considered as an addition to the controversial discussion on the relationship between ASC and breast carcinoma cells. Further studies are needed to quantify the in vivo interaction of ASC and mammary carcinoma cells and to conclusively assess the impact of tamoxifen in reconstructive cases with fat grafting.


Assuntos
Neoplasias da Mama , Carcinoma , Tecido Adiposo/transplante , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Carcinoma/tratamento farmacológico , Transformação Celular Neoplásica , Feminino , Humanos , Células MCF-7 , Células-Tronco , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico
5.
Molecules ; 27(17)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36080141

RESUMO

The Heck cross-coupling reaction is a well-established chemical tool for the synthesis of unsaturated compounds by formation of a new C-C bond. In this study, 1,3-diarylpropene derivatives, designed as structural analogues of stilbenoids and dihydrostilbenoids, were synthesised by the palladium-catalysed reactions of 2-amidoiodobenzene derivatives with either estragole or eugenol. The products were obtained with high (E) stereoselectivity but as two regioisomers. The ratios of isomers were found to be dependent on the nature of the allylbenzene partner and were rationalised by electronic effects exercising a determining influence in the ß-hydride elimination step. In addition, the cytotoxic effects of all the Heck reaction products were evaluated against MCF-7 and MDA-MB-231 human breast cancer cells, with unpromising results. Among all, compound 7d exhibited weak cytotoxic activity towards MCF-7 cell lines with IC50 values of 47.92 µM in comparison with tamoxifen and was considered to have general toxicity (SI value < 2).


Assuntos
Antineoplásicos , Neoplasias da Mama , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Células MCF-7 , Paládio/química , Paládio/farmacologia , Relação Estrutura-Atividade , Tamoxifeno/farmacologia
6.
Dis Model Mech ; 15(9)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35929478

RESUMO

Melanoma heterogeneity and plasticity underlie therapy resistance. Some tumour cells possess innate resistance, while others reprogramme during drug exposure and survive to form persister cells, a source of potential cancer cells for recurrent disease. Tracing individual melanoma cell populations through tumour regression and into recurrent disease remains largely unexplored, in part, because complex animal models are required for live imaging of cell populations over time. Here, we applied tamoxifen-inducible creERt2/loxP lineage tracing to a zebrafish model of MITF-dependent melanoma regression and recurrence to image and trace cell populations in vivo through disease stages. Using this strategy, we show that melanoma persister cells at the minimal residual disease site originate from the primary tumour. Next, we fate mapped rare MITF-independent persister cells and demonstrate that these cells directly contribute to progressive disease. Multiplex immunohistochemistry confirmed that MITF-independent persister cells give rise to Mitfa+ cells in recurrent disease. Taken together, our work reveals a direct contribution of persister cell populations to recurrent disease, and provides a resource for lineage-tracing methodology in adult zebrafish cancer models.


Assuntos
Melanoma , Peixe-Zebra , Animais , Melanoma/patologia , Fator de Transcrição Associado à Microftalmia/genética , Tamoxifeno/farmacologia , Proteínas de Peixe-Zebra
7.
Life Sci Alliance ; 5(11)2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35961777

RESUMO

The developmental origins of lymphatic endothelial cells (LECs) have been under intense research after a century-long debate. Although previously thought to be of solely venous endothelial origin, additional sources of LECs were recently identified in multiple tissues in mice. Here, we investigated the regional differences in the origin(s) of the dermal lymphatic vasculature by lineage tracing using the pan-endothelial Cdh5-CreER T2 line. Tamoxifen-induced labeling of blood ECs at E9.5, before initiation of lymphatic development, traced most of the dermal LECs but with lower efficiency in the lumbar compared with the cervical skin. By contrast, when used at E9.5 but not at E11.5, 4-hydroxytamoxifen, the active metabolite of tamoxifen that provides a tighter window of Cre activity, revealed low labeling frequency of LECs, and lymphvasculogenic clusters in the lumbar skin in particular. Temporally restricted lineage tracing thus reveals contribution of LECs of Cdh5-lineage-independent origin to dermal lymphatic vasculature. Our results further highlight Cre induction strategy as a critical parameter in defining the temporal window for stage-specific lineage tracing during early developmental stages of rapid tissue differentiation.


Assuntos
Células Endoteliais , Vasos Linfáticos , Animais , Células Endoteliais/metabolismo , Vasos Linfáticos/metabolismo , Camundongos , Pele/metabolismo , Tamoxifeno/farmacologia
8.
J Med Life ; 15(6): 835-844, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35928368

RESUMO

Tamoxifen is one of the most used drugs for breast cancer. This study aimed to investigate the effect of the Tamoxifen mechanism on the epithelial-mesenchymal transition (EMT) pathway among breast cancer patients due to its resistance to breast cancer cells. We selected the appropriate datasets from the GEO database using continuous and integrated bioinformatics analysis. We examined the signaling pathways, gene ontology, and protein association of genes after classifying the gene expression profile. Finally, we confirmed the candidate genes using the GEPIA database. Two groups were defined for gene expression profiles. The first group in which the expression profile of genes increased after Tamoxifen was evaluated using the expression profile of genes that decreased in the EMT pathway. The second group was the opposite of the first group. 253 genes in the first group and 302 genes in the second group were shared. The genes in the first group were involved in various pathways of cell death, focal adhesion, and cellular aging. The second group was more involved in different phases of the cell cycle. Finally, MYLK, SOCS3, and STAT5B proteins from the first group and BIRC5, PLK1, and RAPGAP1 proteins from the second group were selected as candidate proteins in connection with the effect of Tamoxifen on the EMT pathway. We evaluated Tamoxifen's effect on the EMT pathway more accurately. However, for a closer look at Tamoxifen, more studies need to be done on target genes and proteins to clarify their role.


Assuntos
Neoplasias da Mama , Resistencia a Medicamentos Antineoplásicos , Transição Epitelial-Mesenquimal , Tamoxifeno , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Resistencia a Medicamentos Antineoplásicos/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico
9.
Cell Rep ; 40(8): 111248, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36001977

RESUMO

Voltage-gated sodium channels (NaV) in nociceptive neurons initiate action potentials required for transmission of aberrant painful stimuli observed in osteoarthritis (OA). Targeting NaV subtypes with drugs to produce analgesic effects for OA pain management is a developing therapeutic area. Previously, we determined the receptor site for the tamoxifen analog N-desmethyltamoxifen (ND-Tam) within a prokaryotic NaV. Here, we report the pharmacology of ND-Tam against eukaryotic NaVs natively expressed in nociceptive neurons. ND-Tam and analogs occupy two conserved intracellular receptor sites in domains II and IV of NaV1.7 to block ion entry using a "bind and plug" mechanism. We find that ND-Tam inhibition of the sodium current is state dependent, conferring a potent frequency- and voltage-dependent block of hyperexcitable nociceptive neuron action potentials implicated in OA pain. When evaluated using a mouse OA pain model, ND-Tam has long-lasting efficacy, which supports the potential of repurposing ND-Tam analogs as NaV antagonists for OA pain management.


Assuntos
Tamoxifeno , Canais de Sódio Disparados por Voltagem , Potenciais de Ação , Gânglios Espinais , Humanos , Nociceptores , Dor/tratamento farmacológico , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico
10.
PLoS One ; 17(8): e0273513, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36006984

RESUMO

Glycosylation is one of the most important post-translational modifications of cell surface proteins involved in the proliferation, metastasis and treatment resistance of cancer cells. However, little is known about the role of glycosylation as the mechanism of breast cancer cell resistance to endocrine therapy. Herein, we aimed to identify the glycan profiles of tamoxifen-resistant human breast cancer cells, and their potential as predictive biomarkers for endocrine therapy. We established tamoxifen-resistant cells from estrogen receptor-positive human breast cancer cell lines, and their membrane-associated proteins were subjected to lectin microarray analysis. To confirm differential lectin binding to cellular glycoproteins, we performed lectin blotting analyses after electrophoretic separation of the glycoproteins. Mass spectrometry of the tryptic peptides of the lectin-bound glycoproteins was further conducted to identify glycoproteins binding to the above lectins. Finally, expression of the glycans that were recognized by a lectin was investigated using clinical samples from patients who received tamoxifen treatment after curative surgery. Lectin microarray analysis revealed that the membrane fractions of tamoxifen-resistant breast cancer cells showed increased binding to Wisteria floribunda agglutinin (WFA) compared to tamoxifen-sensitive cells. Glycoproteins seemed to be responsible for the differential WFA binding and the results of mass spectrometry revealed several membrane glycoproteins, such as CD166 and integrin beta-1, as candidates contributing to increased WFA binding. In clinical samples, strong WFA staining was more frequently observed in patients who had developed distant metastasis during tamoxifen treatment compared with non-relapsed patients. Therefore, glycans recognized by WFA are potentially useful as predictive markers to identify the tamoxifen-resistant and relapse-prone subset of estrogen receptor-positive breast cancer patients.


Assuntos
Neoplasias da Mama , Tamoxifeno , Antígenos de Neoplasias , Biomarcadores , Neoplasias da Mama/tratamento farmacológico , Feminino , Glicoproteínas/metabolismo , Humanos , Recidiva Local de Neoplasia , Lectinas de Plantas/metabolismo , Polissacarídeos/metabolismo , Receptores de Estrogênio , Receptores de N-Acetilglucosamina/metabolismo , Tamoxifeno/farmacologia
11.
Chem Biol Interact ; 365: 110091, 2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-35944649

RESUMO

Estrogen receptor α (ERα) plays a key role in the adaptive response of liver metabolism to energy demands, especially in controlling lipid metabolism. Tamoxifen (TMX), a main drug for the treatment of ER-positive breast cancer in clinical, is a selective ER modulator (SERM). However, accordingly, the long-term use of TMX would lead to nonalcoholic fatty liver (NAFLD) in clinical, which had no definite treatment up to now. Fatostatin (Fato), an inhibitor of sterol-regulatory element binding protein 2 (SREBP2), was reported as a synergistic inhibitor of ER-positive breast cancer with TMX, but the hepatic lipid regulation of this combination is still unknown. Herein, we aimed to explore the effect and mechanism of Fato against TMX-induced NAFLD. The results identified that hepatic cholesterol content increase was the main reason for TMX-induced NAFLD. It was caused by the upregulation of circulating cholesterol uptake mediated by low density lipoprotein receptor (LDLR) in liver, which resulted from the activation of SREBP2. Meanwhile, Fato could inhibit activation of SREBP2-LDLR pathway, alleviating TMX-induced hepatic cholesterol accumulation. In summary, these results provided a new insight into the mechanism of TMX-induced NAFLD. Moreover, it supported the combination of Fato and TMX for the treatment of ER-positive breast cancer to reduce the adverse effect of TMX in clinical.


Assuntos
Neoplasias da Mama , Hepatopatia Gordurosa não Alcoólica , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Colesterol/metabolismo , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Fígado , Hepatopatia Gordurosa não Alcoólica/metabolismo , Piridinas , Receptores de LDL/metabolismo , Moduladores Seletivos de Receptor Estrogênico/metabolismo , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Tamoxifeno/farmacologia , Tiazóis
12.
Theranostics ; 12(13): 5761-5775, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35966598

RESUMO

Rationale: Approximately 30-40% of estrogen receptor (ER)-positive breast cancer (BC) cases recur after tamoxifen therapy. Thus, additional studies on the mechanisms underlying tamoxifen resistance and more specific prognostic biomarkers are required. In this study, we investigated the role of the SET domain containing 1A (SETD1A), a histone H3-lysine 4 (H3K4) methyltransferase, in the development of tamoxifen resistance in BC. Methods: The relationship between tamoxifen resistance and SETD1A protein level was investigated using resistant cell lines derived from the parent BC cells. Biochemical and molecular assays, such as RNA-sequencing, reverse transcription-quantitative polymerase chain reaction, chromatin-immunoprecipitation, and protein-binding assays, were used to identify the SETD1A target gene in tamoxifen-resistant BC cells. Additionally, the role of SETD1A in cancer stem cells (CSCs) was investigated using CSCs isolated from tamoxifen-resistant BC cells. Comprehensive transcriptome analysis and immunofluorescence staining using clinical datasets and tissue microarray were performed to determine the correlation between the expression of the SETD1A-SRY-box transcription factor 2 (SOX2) pair and recurrence in tamoxifen-treated patients with BC. Results: SETD1A was expressed at higher levels in tamoxifen-resistant BC cells than in primary BC cells. Notably, SETD1A-depleted tamoxifen-resistant MCF-7 cells showed restored sensitivity to tamoxifen, whereas SETD1A overexpression in MCF-7 cells resulted in decreased sensitivity. SETD1A is recruited to the SOX2 gene via its interaction with SOX2, thereby enhancing the expression of SOX2 genes in tamoxifen-resistant BC cells. The growth of tamoxifen-resistant cells and CSCs was effectively suppressed by SETD1A knockdown. In addition, high levels of SETD1A and SOX2 were significantly correlated with a low survival rate in patients with ER-positive tamoxifen-resistant BC. Conclusion: Our findings provide the first evidence of the critical role of the SETD1A-SOX2 axis in tamoxifen-resistant BC cells, implying that SETD1A may serve as a molecular target and prognostic indicator of a therapeutic response in patients with tamoxifen-resistant BC.


Assuntos
Neoplasias da Mama , Tamoxifeno , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Resistencia a Medicamentos Antineoplásicos , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Feminino , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Células MCF-7 , Fatores de Transcrição SOXB1/genética , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico
13.
J Bone Miner Res ; 37(9): 1750-1760, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35789113

RESUMO

Estrogen is known to regulate bone metabolism in both women and men, but substantial gaps remain in our knowledge of estrogen and estrogen receptor alpha (ERα) regulation of adult bone metabolism. Studies using global ERα-knockout mice were confounded by high circulating sex-steroid levels, and osteocyte/osteoblast-specific ERα deletion may be confounded by ERα effects on growth versus the adult skeleton. Thus, we developed mice expressing the tamoxifen-inducible CreERT2 in osteocytes using the 8-kilobase (kb) Dmp1 promoter (Dmp1CreERT2 ). These mice were crossed with ERαfl//fl mice to create ERαΔOcy mice, permitting inducible osteocyte-specific ERα deletion in adulthood. After intermittent tamoxifen treatment of adult 4-month-old mice for 1 month, female, but not male, ERαΔOcy mice exhibited reduced spine bone volume fraction (BV/TV (-20.1%, p = 0.004) accompanied by decreased trabecular bone formation rate (-18.9%, p = 0.0496) and serum P1NP levels (-38.9%, p = 0.014). Periosteal (+65.6%, p = 0.004) and endocortical (+64.1%, p = 0.003) expansion were higher in ERαΔOcy mice compared to control (Dmp1CreERT2 ) mice at the tibial diaphysis, reflecting the known effects of estrogen to inhibit periosteal apposition and promote endocortical formation. Increases in Sost (2.1-fold, p = 0.001) messenger RNA (mRNA) levels were observed in trabecular bone at the spine in ERαΔOcy mice, consistent with previous reports that estrogen deficiency is associated with increased circulating sclerostin as well as bone SOST mRNA levels in humans. Further, the biological consequences of increased Sost expression were reflected in significant overall downregulation in panels of osteoblast and Wnt target genes in osteocyte-enriched bones from ERαΔOcy mice. These findings thus establish that osteocytic ERα is critical for estrogen action in female, but not male, adult bone metabolism. Moreover, the reduction in bone formation accompanied by increased Sost, decreased osteoblast, and decreased Wnt target gene expression in ERαΔOcy mice provides a direct link in vivo between ERα and Wnt signaling. © 2022 American Society for Bone and Mineral Research (ASBMR).


Assuntos
Receptor alfa de Estrogênio , Osteócitos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Animais , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Estrogênios/metabolismo , Estrogênios/farmacologia , Feminino , Humanos , Lactente , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Masculino , Camundongos , Camundongos Knockout , Osteoblastos/metabolismo , Osteócitos/metabolismo , RNA Mensageiro/metabolismo , Tamoxifeno/farmacologia
14.
Steroids ; 186: 109075, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35792153

RESUMO

3,3-bis(4-hydroxyphenyl)-7-methyl-1,3,dihydro-2H-indol-2-one (BHPI) is a biomodulator of Estrogen Receptor alpha (ERα) that targets ERα positive cancer cells by activating the unfolded protein response (UPR). BHPI induces strong and sustained activation of this pathway, eventually resulting in necrotic cell death. While much is known about how BHPI triggers the UPR leading to necrotic cell death, it is not known how BHPI binds to its putative molecular target, ERα. In an effort to identify the binding site of BHPI on ERα, molecular docking studies in AutoDock Vina were utilized. Unexpectedly, BHPI was found to dock more frequently and with significantly better binding affinity to a newly described surface pocket on the ERα ligand-binding domain, compared to the ligand-binding pocket. This work uncovers a novel binding site for small molecules on ERα that is not targeted by classical ligands, such as estrogen and tamoxifen, and may allow for the design of additional anti-cancer drugs that work in distinct ways.


Assuntos
Receptor alfa de Estrogênio , Tamoxifeno , Sítios de Ligação , Receptor alfa de Estrogênio/metabolismo , Ligantes , Simulação de Acoplamento Molecular , Ligação Proteica , Tamoxifeno/farmacologia
15.
Cell Biol Int ; 46(10): 1661-1671, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35819094

RESUMO

The interaction of cancer cells with their tumor microenvironment determines key events in the progression of the disease, therapeutic efficacy, and the development of drug resistance. Here, we presented evidence that tamoxifen support breast cancer growth during nutrition deprivation by modulating mitochondrial dynamics through AMPK and MAPK signaling. Tamoxifen enhances mitochondrial fusion under nutrition-deprived conditions by suppressing Drp1 ser616 phosphorylation and upregulating Mfn1 levels. Tamoxifen-induced mitochondrial fusion is mediated by the activation of AMPK as evident by the pharmacological inhibition of AMPK reverse mitochondrial fusion. Interestingly, JNK activation by tamoxifen controls the mitochondrial fusion morphology by downregulating Mfn2. Collectively, tamoxifen support cell growth by enhancing mitochondrial fusion by regulating stress kinase signaling under nutrition deprivation condition.


Assuntos
Dinâmica Mitocondrial , Tamoxifeno , Proteínas Quinases Ativadas por AMP/metabolismo , Humanos , Dinâmica Mitocondrial/fisiologia , Fosforilação , Transdução de Sinais , Tamoxifeno/farmacologia
16.
Adv Sci (Weinh) ; 9(25): e2201701, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35843886

RESUMO

Estrogen receptor alpha (ER-α) action is critical for hormone-dependent breast cancer, and ER-α dysregulation can lead to the emergence of resistance to endocrine therapy. Here, it is found that TRIM4 is downregulated in tamoxifen (TAM)-resistant breast cancer cells, while the loss of TRIM4 is associated with an unfavorable prognosis. In vitro and in vivo experiments confirm that TRIM4 increased ER-α expression and the sensitivity of breast cancer cells to TAM. Mechanistically, TRIM4 is found to target SET, and TRIM4-SET interactions are mediated by the RING and B-box domains of TRIM4 and the carboxyl terminus of SET. Moreover, it is determined that TRIM4 catalyzed the K48-linked polyubiquitination of SET (K150 and K172), promoting its proteasomal degradation and disassociation from p53 and PP2A. Once released, p53 and PP2A are able to further promote ESR1 gene transcription and enhance mRNA stability. Moreover, univariate and multivariate Cox proportional hazards regression analyses confirm that TRIM4 expression is an independent predictor of overall survival and recurrence-free survival outcomes in patients with ER-α positive breast cancer. Taken together, the data highlights a previously undiscovered mechanism and suggest that TRIM4 is a valuable biomarker that can be analyzed to predict response to endocrine therapy in breast cancer patients.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/genética , Proteínas de Ligação a DNA , Receptor alfa de Estrogênio , Feminino , Chaperonas de Histonas , Humanos , Tamoxifeno/farmacologia , Proteínas com Motivo Tripartido , Proteína Supressora de Tumor p53 , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
17.
Int J Mol Sci ; 23(15)2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35897675

RESUMO

Approximately 75% of diagnosed breast cancer tumors are estrogen-receptor-positive tumors and are associated with a better prognosis due to response to hormonal therapies. However, around 40% of patients relapse after hormonal therapies. Genomic analysis of gene expression profiles in primary breast cancers and tamoxifen-resistant cell lines suggested the potential role of miR-489 in the regulation of estrogen signaling and development of tamoxifen resistance. Our in vitro analysis showed that loss of miR-489 expression promoted tamoxifen resistance, while overexpression of miR-489 in tamoxifen-resistant cells restored tamoxifen sensitivity. Mechanistically, we found that miR-489 is an estrogen-regulated miRNA that negatively regulates estrogen receptor signaling by using at least the following two mechanisms: (i) modulation of the ER phosphorylation status by inhibiting MAPK and AKT kinase activities; (ii) regulation of nuclear-to-cytosol translocation of estrogen receptor α (ERα) by decreasing p38 expression and consequently ER phosphorylation. In addition, miR-489 can break the positive feed-forward loop between the estrogen-Erα axis and p38 MAPK in breast cancer cells, which is necessary for its function as a transcription factor. Overall, our study unveiled the underlying molecular mechanism by which miR-489 regulates an estrogen signaling pathway through a negative feedback loop and uncovered its role in both the development of and overcoming of tamoxifen resistance in breast cancers.


Assuntos
Neoplasias da Mama , MicroRNAs , Antineoplásicos Hormonais/farmacologia , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Receptor alfa de Estrogênio/metabolismo , Estrogênios/farmacologia , Retroalimentação , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/metabolismo , Recidiva Local de Neoplasia/genética , Transdução de Sinais , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico
18.
Front Immunol ; 13: 918636, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35874787

RESUMO

Current genetic tools designed to target macrophages in vivo often target cells from all myeloid lineages. Therefore, we sought to generate a novel transgenic mouse which has a tamoxifen inducible Cre-recombinase under the control of the human CD68 promoter (hCD68-CreERT2). To test the efficiency and specificity of the of Cre-recombinase activity we crossed the hCD68-CreERT2 mice with a loxP-flanked STOP cassette red fluorescent protein variant (tdTomato) mouse. We established that orally dosing mice with 2 mg of tamoxifen for 5 consecutive days followed by a 5-day induction period resulted in robust expression of tdTomato in CD11b+ F4/80+ tissue resident macrophages. Using this induction protocol, we demonstrated tdTomato expression within peritoneal, liver and spleen macrophages and blood Ly6Clow monocytes. Importantly there was limited or no inducible tdTomato expression within other myeloid cells (neutrophils, monocytes, dendritic cells and eosinophils), T cells (CD4+ and CD8+) and B cells (CD19+). We also demonstrated that the level of tdTomato expression can be used as a marker to identify different populations of peritoneal and liver macrophages. We next assessed the longevity of tdTomato expression in peritoneal macrophages, liver and splenic macrophages and demonstrated high levels of tdTomato expression as long as 6 weeks after the last tamoxifen dose. Importantly, hCD68-CreERT2 expression is more restricted than that of LysM-Cre which has significant expression in major myeloid cell types (monocytes and neutrophils). To demonstrate the utility of this novel macrophage-specific Cre driver line we demonstrated tdTomato expression in recruited CD11b+CD64+F4/80+ monocyte-derived macrophages within the atherosclerotic lesions of AAV8-mPCSK9 treated mice, with limited expression in recruited neutrophils. In developing this new hCD68-CreERT2 mouse we have a tool that allows us to target tissue resident macrophages, with the advantage of not targeting other myeloid cells namely neutrophils and inflammatory monocytes.


Assuntos
Integrases , Tamoxifeno , Animais , Humanos , Integrases/genética , Macrófagos/metabolismo , Camundongos , Camundongos Transgênicos , Tamoxifeno/farmacologia
19.
Asian Pac J Cancer Prev ; 23(7): 2341-2350, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35901340

RESUMO

BACKGROUND: Tamoxifen is the drug of choice for treating breast cancer, particularly the estrogen receptor-positive luminal A subtype. However, the increased occurrence of Tamoxifen resistance highlights the need to develop an agent to enhance the effectiveness of this drug. OBJECTIVE: Although glycyrrhizic acid (GA) is known to exhibit cytotoxic effects on Michigan Cancer Foundation-7 cells, the specific gene targets and pathways it employs to overcome Tamoxifen resistance are incompletely understood. Therefore, the goal of the present research is to discover the potential targets and pathways of GA by using a bioinformatics approach. METHODS: Differentially expressed genes (DEGs) were identified in the Gene Expression Omnibus NCBI database using microarray data from GSE67916 and GSE85871. Further analyses were performed on these DEGs by using DAVID v6.8, STRING-DB v11.0, and Cytoscape v3.8.0. Analysis of gene alterations was performed using cBioPortal for target validation, and the relevant interaction process was examined via the molecular docking method. RESULTS: Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses identified the PI3K-AKT signaling as the potential target mechanism. Construction of the protein-protein interaction network and analysis of hub genes identified the top 25 hub genes. Genetic alterations were observed in six potential target genes, such as CDK2, MDM2, NF1, SMAD3, PTPN11, and CALM1. Molecular docking analysis demonstrated that the docking score of GA is lower than that of the native ligand of p53. More importantly, 3n the PI3K-AKT signaling pathway is a potential target for overcoming Tamoxifen resistance in breast cancer. CONCLUSION: MDM2 may be a potential gene target of GA and the PI3K-AKT signaling may be a prospective mechanism for overcoming Tamoxifen resistance in breast cancer cells. Additional research is required to validate the findings of this study.


Assuntos
Neoplasias da Mama , Biologia Computacional , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Biologia Computacional/métodos , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Ácido Glicirrízico/farmacologia , Humanos , Simulação de Acoplamento Molecular , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Tamoxifeno/farmacologia
20.
J Biomed Opt ; 27(7)2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35831923

RESUMO

SIGNIFICANCE: Imaging needles consist of highly miniaturized focusing optics encased within a hypodermic needle. The needles may be inserted tens of millimeters into tissue and have the potential to visualize diseased cells well beyond the penetration depth of optical techniques applied externally. Multimodal imaging needles acquire multiple types of optical signals to differentiate cell types. However, their use has not previously been demonstrated with live cells. AIM: We demonstrate the ability of a multimodal imaging needle to differentiate cell types through simultaneous optical coherence tomography (OCT) and fluorescence imaging. APPROACH: We characterize the performance of a multimodal imaging needle. This is paired with a fluorescent analog of the therapeutic drug, tamoxifen, which enables cell-specific fluorescent labeling of estrogen receptor-positive (ER+) breast cancer cells. We perform simultaneous OCT and fluorescence in situ imaging on MCF-7 ER+ breast cancer cells and MDA-MB-231 ER- cells. Images are compared against unlabeled control samples and correlated with standard confocal microscopy images. RESULTS: We establish the feasibility of imaging live cells with these miniaturized imaging probes by showing clear differentiation between cancerous cells. CONCLUSIONS: Imaging needles have the potential to aid in the detection of specific cancer cells within solid tissue.


Assuntos
Neoplasias da Mama , Tomografia de Coerência Óptica , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Feminino , Humanos , Imagem Multimodal , Agulhas , Tamoxifeno/farmacologia , Tomografia de Coerência Óptica/métodos
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