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1.
J Endocrinol Invest ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38900374

RESUMO

BACKGROUND: Thyroid cancer is the most common endocrine malignancy. Current therapies are successful, however some patients progress to therapeutically refractive disease. The immunotherapeutic potential of the CXCL8-chemokine/CXCR2-chemokine-receptor system is currently being explored in numerous human cancers. This study aimed to evaluate if the targeting of CXCR2 by its selective antagonist, AZD5069, could modulate CXCL8-mediated pro-tumorigenic effects in thyroid-cancer (TC) cells in vitro. METHODS: Normal human primary thyroid cells (NHT) and TC cell lines TPC-1 (RET/PTC), BCPAP, 8505C and 8305C (BRAFV600e) were treated with AZD5069 (100 pM-10 µM) over a time-course. Viability and proliferation were assessed by WST-1 and crystal violet assays. CXCL8 and CXCR2 mRNA were evaluated by RT-PCR. CXCL8-protein concentrations were measured in cell culture supernatants by ELISA. CXCR2 on cell surface was evaluated by flow-cytometry. Cell-migration was assessed by trans-well-migration chamber-system. RESULTS: AZD5069 exerted negligible effects on cell proliferation or viability. AZD5069 significantly reduced CXCR2, (but not CXCL8) mRNAs in all cell types. CXCR2 was reduced on the membrane of some TC cell lines. A significant reduction of the CXCL8 secretion was found in TPC-1 cells (basal-secretion) and NHT (TNFα-induced secretion). AZD5069 significantly reduced basal and CXCL8-induced migration in NHT and different TC cells. CONCLUSIONS: Our findings confirm the involvement of the CXCL8/CXCR2-axis in promoting pro-tumorigenic effects in TC cells, further demonstrating its immunotherapeutic significance in human cancer.

2.
Cancers (Basel) ; 16(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38730605

RESUMO

Rhabdomyosarcoma is a pediatric cancer associated with aggressiveness and a tendency to develop metastases. Fusion-negative rhabdomyosarcoma (FN-RMS) is the most commonly occurring subtype of RMS, where metastatic disease can hinder treatment success and decrease survival rates. RMS-derived exosomes were previously demonstrated to be enriched with miRNAs, including miR-1246, possibly contributing to disease aggressiveness. We aimed to decipher the functional impact of exosomal miR-1246 on recipient cells and its role in promoting aggressiveness. Treatment of normal fibroblasts with FN-RMS-derived exosomes resulted in a significant uptake of miR-1246 paired with an increase in cell proliferation, migration, and invasion. In turn, delivery of miR-1246-mimic lipoplexes promoted fibroblast proliferation, migration, and invasion in a similar manner. Conversely, when silencing miR-1246 in FN-RMS cells, the resulting derived exosomes demonstrated reversed effects on recipient cells' phenotype. Delivery of exosomal miR-1246 targets GSK3ß and promotes ß-catenin nuclear accumulation, suggesting a deregulation of the Wnt pathway, known to be important in tumor progression. Finally, a pilot clinical study highlighted, for the first time, the presence of high exosomal miR-1246 levels in RMS patients' sera. Altogether, our results demonstrate that exosomal miR-1246 has the potential to alter the tumor microenvironment of FN-RMS cells, suggesting its potential role in promoting oncogenesis.

3.
Cancers (Basel) ; 14(24)2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36551531

RESUMO

The oncogenic transcription factor ZNF217 orchestrates several molecular signaling networks to reprogram integrated circuits governing hallmark capabilities within cancer cells. High levels of ZNF217 expression provide advantages to a specific subset of cancer cells to reprogram tumor progression, drug resistance and cancer cell plasticity. ZNF217 expression level, thus, provides a powerful biomarker of poor prognosis and a predictive biomarker for anticancer therapies. Cancer epigenetic mechanisms are well known to support the acquisition of hallmark characteristics during oncogenesis. However, the complex interactions between ZNF217 and epigenetic processes have been poorly appreciated. Deregulated DNA methylation status at ZNF217 locus or an intricate cross-talk between ZNF217 and noncoding RNA networks could explain aberrant ZNF217 expression levels in a cancer cell context. On the other hand, the ZNF217 protein controls gene expression signatures and molecular signaling for tumor progression by tuning DNA methylation status at key promoters by interfering with noncoding RNAs or by refining the epitranscriptome. Altogether, this review focuses on the recent advances in the understanding of ZNF217 collaboration with epigenetics processes to orchestrate oncogenesis. We also discuss the exciting burgeoning translational medicine and candidate therapeutic strategies emerging from those recent findings connecting ZNF217 to epigenetic deregulation in cancer.

4.
Front Pharmacol ; 13: 951833, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36046820

RESUMO

Diabetic retinopathy (DR), one of the most common complications of diabetes mellitus, is characterized by degeneration of retinal neurons and neoangiogenesis. Until today, the pharmacological approaches for DR are limited and focused on counteracting the end-stage of this neurodegenerative disease, therefore efforts should be carried out to discover novel pharmacological targets useful to prevent DR development. Hyperglycemia is a major risk factor for endothelial dysfunction and vascular complication, which subsequently may trigger neurodegeneration. We previously demonstrated that, in the rat retina, hyperglycemia activates a new molecular cascade implicating, up-stream, protein kinase C ßII (PKC ßII), which in turn leads to a higher expression of vascular endothelial growth factor (VEGF), via the mRNA-binding Hu-antigen R (HuR) protein. VEGF is a pivotal mediator of neovascularization and a well-known vasopermeability factor. Blocking the increase of VEGF via modulation of this cascade can thus represent a new pharmacological option to prevent DR progression. To this aim, proper in vitro models are crucial for drug discovery, as they allow to better identify promising effective molecules. Considering that endothelial cells are key elements in DR and that hyperglycemia triggers the PKCßII/HuR/VEGF pathway, we set up two distinct in vitro models applying two different stimuli. Namely, human umbilical vein endothelial cells were exposed to phorbol 12-myristate 13-acetate, which mimics diacylglycerol whose synthesis is triggered by diabetic hyperglycemia, while human retinal endothelial cells were treated with high glucose for different times. After selecting the optimal experimental conditions able to determine an increased VEGF production, in search of molecules useful to prevent DR development, we investigated the capability of troxerutin, an antioxidant flavonoid, to counteract not only the rise of VEGF but also the activation of the PKCßII/HuR cascade in both in vitro models. The results show the capability of troxerutin to hinder the hyperglycemia-induced increase in VEGF in both models through PKCßII/HuR pathway modulation. Further, these data confirm the key engagement of this cascade as an early event triggered by hyperglycemia to promote VEGF expression. Finally, the present findings also suggest the potential use of troxerutin as a preventive treatment during the early phases of DR.

5.
Front Oncol ; 12: 971174, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36033507

RESUMO

Rhabdomyosarcoma (RMS) is a soft tissue sarcoma of skeletal muscle differentiation, with a predominant occurrence in children and adolescents. One of the major challenges facing treatment success is the presence of metastatic disease at the time of diagnosis, commonly associated with the more aggressive fusion-positive subtype. Non-coding RNA (ncRNA) can regulate gene transcription and translation, and their dysregulation has been associated with cancer development and progression. MicroRNA (miRNA) are short non-coding nucleic acid sequences involved in the regulation of gene expression that act by targeting messenger RNA (mRNA), and their aberrant expression has been associated with both RMS initiation and progression. Other ncRNA including long non-coding RNA (lncRNA), circular RNA (circRNA) and ribosomal RNA (rRNA) have also been associated with RMS revealing important mechanistic roles in RMS biology, but these studies are still limited and require further investigation. In this review, we discuss the established roles of ncRNA in RMS differentiation, growth and progression, highlighting their potential use in RMS prognosis, as therapeutic agents or as targets of treatment.

6.
Bioscience ; 72(4): 372-386, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35370478

RESUMO

Ecosystem management and governance of cross-scale dependent systems require integrating knowledge about ecological connectivity in its multiple forms and scales. Although scientists, managers, and policymakers are increasingly recognizing the importance of connectivity, governmental organizations may not be currently equipped to manage ecosystems with strong cross-boundary dependencies. Managing the different aspects of connectivity requires building social connectivity to increase the flow of information, as well as the capacity to coordinate planning, funding, and actions among both formal and informal governance bodies. We use estuaries in particular the San Francisco Estuary, in California, in the United States, as examples of cross-scale dependent systems affected by many intertwined aspects of connectivity. We describe the different types of estuarine connectivity observed in both natural and human-affected states and discuss the human dimensions of restoring beneficial physical and ecological processes. Finally, we provide recommendations for policy, practice, and research on how to restore functional connectivity to estuaries.

8.
EFORT Open Rev ; 6(11): 1040-1051, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34909223

RESUMO

Total hip arthroplasty is performed more frequently in younger patients nowadays, making long-term bone stock preservation an important topic. A mechanism for late implant failure is periprosthetic bone loss, caused by stress shielding around the hip stem due to different load distribution. Short stems are designed to keep the physical loading in the proximal part of the femur to reduce stress shielding. The aim of this review is to give more insight into how short and anatomic stems behave and whether they succeed in preservation of proximal bone stock.A systematic literature search was performed to find all published studies on bone mineral density in short and anatomic hip stems. Results on periprosthetic femoral bone mineral density, measured with dual-energy X-ray absorptiometry (DEXA), were compiled and analysed per Gruen zone in percentual change.A total of 29 studies were included. In short stems, Gruen 1 showed bone loss of 5% after one year (n = 855) and 5% after two years (n = 266). Gruen 7 showed bone loss of 10% after one year and -11% after two years. In anatomic stems, Gruen 1 showed bone loss of 8% after one year (n = 731) and 11% after two years (n = 227). Gruen 7 showed bone loss of 14% after one year and 15% after two years.Short stems are capable of preserving proximal bone stock and have slightly less proximal bone loss in the first years, compared to anatomic stems. Cite this article: EFORT Open Rev 2021;6:1040-1051. DOI: 10.1302/2058-5241.6.210030.

9.
Front Oncol ; 11: 647269, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34277402

RESUMO

Oncogene alternative splicing events can create distinct functional transcripts that offer new candidate prognostic biomarkers for breast cancer. ZNF217 is a well-established oncogene but its exon 4-skipping isoform (ZNF217-ΔE4) has never been investigated in terms of clinical or biological relevance. Using in silico RNA-seq and RT-qPCR analyses, we demonstrated for the first time the existence of ZNF217-ΔE4 transcripts in primary breast tumors, and a positive correlation between ZNF217-ΔE4 mRNA levels and those of the wild-type oncogene (ZNF217-WT). A pilot retrospective analysis revealed that, in the Luminal subclass, the combination of the two ZNF217 variants (the ZNF217-ΔE4-WT gene-expression signature) provided more information than the mRNA expression levels of each isoform alone. Ectopic overexpression of ZNF217-ΔE4 in breast cancer cells promoted an aggressive phenotype and an increase in ZNF217-WT expression levels that was inversely correlated with DNA methylation of the ZNF217 gene. This study provides new insights into the possible role of the ZNF217-ΔE4 splice variant in breast cancer and suggests a close interplay between the ZNF217-WT and ZNF217-ΔE4 isoforms. Our data suggest that a dual signature combining the expression levels of these two isoforms may serve as a novel prognostic biomarker allowing better stratification of breast cancers with good prognosis and aiding clinicians in therapeutic decisions.

11.
Front Oncol ; 10: 712, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32670863

RESUMO

It is of utmost importance to decipher the role of chronic exposure to low doses of environmental carcinogens on breast cancer progression. The early-transformed triple-negative human mammary MCF10AT1 cells were chronically (60 days) exposed to low doses (10-10 M) of Benzo[a]pyrene (B[a]P), a genotoxic agent, and/or Bisphenol A (BPA), an endocrine disruptor. Our study revealed that exposed MCF10AT1 cells developed, in a time-dependent manner, an acquired phenotype characterized by an increase in cancerous properties (anchorage independent growth and stem-like phenotype). Co-exposure of MCF10AT1 cells to B[a]P and BPA led to a significantly greater aggressive phenotype compared to B[a]P or BPA alone. This study provided new insights into the existence of a functional interplay between the aryl hydrocarbon receptor (AhR) and the G protein-coupled receptor 30 (GPR30) by which chronic and low-dose exposure of B[a]P and/or BPA fosters the progression of MCF10AT1 cells into a more aggressive substage. Experiments using AhR or GPR30 antagonists, siRNA strategies, and RNAseq analysis led us to propose a model in which AhR signaling plays a "driver role" in the AhR/GPR30 cross-talk in mediating long-term and low-dose exposure of B[a]P and/or BPA. Retrospective analysis of two independent breast cancer cohorts revealed that the AhR/GPR30 mRNA expression signature resulted in poor breast cancer prognosis, in particular in the ER-negative and the triple-negative subtypes. Finally, the study identified targeting AhR and/or GPR30 with specific antagonists as a strategy capable of inhibiting carcinogenesis associated with chronic exposure to low doses of B[a]P and BPA in MCF10AT1 cells. Altogether, our results indicate that the engagement of both AhR and GPR30 functions, in particular in an ER-negative/triple-negative context of breast cells, favors tumor progression and leads to poor prognosis.

12.
Sci Rep ; 10(1): 6813, 2020 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-32321959

RESUMO

Consecutive adults scheduled to undergo abdominal CT with oral contrast were asked to choose between 1000 ml water only or positive oral contrast (50 ml Télébrix-Gastro diluted in 950 ml water). Two abdominal radiologists independently reviewed each scan for image quality of the abdomen, the diagnostic confidence per system (gastrointestinalsystem/organs/peritoneum/retroperitoneum/lymph nodes) and overall diagnostic confidence to address the clinical question (not able/partial able/fully able). Radiation exposure was extracted from dose reports. Differences between both groups were evaluated by Student's t-test, Mann-Whitney-U-test or chi-square-test. Of the 320participants, 233chose water only. All baseline characteristics, image quality of the abdomen and the diagnostic confidence of the organs were comparable between groups and both observers. Diagnostic confidence in the water only group was more commonly scored as less than good by observer1. The results were as follows: the gastrointestinal system(18/233vs1/87; p = 0.031), peritoneum (21/233vs1/87; p = 0.012), retroperitoneum (11/233vs0/87; p = 0.040) and lymph nodes (11/233vs0/87; p = 0.040). These structures were scored as comparable between both groups by observer2. The diagnostic confidence to address the clinical question could be partially addressed in 6/233 vs 0/87 patients (p = 0.259). The water only group showed a tendency towards less radiation exposure. In summary, most scan ratings were comparable between positive contrast and water only, but slightly favored positive oral contrast for one reader for some abdominal structures. Therefore, water only can replace positive oral contrast in the majority of the outpatients scheduled to undergo an abdominal CT.


Assuntos
Abdome/diagnóstico por imagem , Meios de Contraste/administração & dosagem , Tomografia Computadorizada por Raios X , Água/administração & dosagem , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Especificidade de Órgãos , Estudos Prospectivos , Exposição à Radiação
13.
Infect Dis Poverty ; 9(1): 3, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31931879

RESUMO

BACKGROUND: Social Innovation in health initiatives have the potential to address unmet community health needs. For sustainable change to occur, we need to understand how and why a given intervention is effective. Bringing together communities, innovators, researchers, and policy makers is a powerful way to address this knowledge gap but differing priorities and epistemological backgrounds can make collaboration challenging. MAIN TEXT: To overcome these barriers, stakeholders will need to design policies and work in ways that provide an enabling environment for innovative products and services. Inherently about people, the incorporation of community engagement approaches is necessary for both the development of social innovations and accompanying research methodologies. Whilst the 'appropriate' level of participation is linked to intended outcomes, researchers have a role to play in better understanding how to harness the power of community engagement and to ensure that community perspectives form part of the evidence base that informs policy and practice. CONCLUSIONS: To effectively operate at the intersection between policy, social innovation, and research, all collaborators need to enter the process with the mindset of learners, rather than experts. Methods - quantitative and qualitative - must be selected according to research questions. The fields of implementation research, community-based participatory research, and realist research, amongst others, have much to offer. So do other sectors, notably education and business. In all this, researchers must assume the mantel of responsibility for research and not transfer the onus to communities under the guise of participation. By leveraging the expertise and knowledge of different ecosystem actors, we can design responsive health systems that integrate innovative approaches in ways that are greater than the sum of their parts.


Assuntos
Pesquisa Participativa Baseada na Comunidade/organização & administração , Atenção à Saúde/organização & administração , Política de Saúde , Inovação Organizacional , Pesquisa Qualitativa , Participação da Comunidade
14.
Disabil Rehabil ; 42(22): 3189-3198, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-30950658

RESUMO

Purpose: A stroke is a sudden event which may leave individuals and their families ill-prepared to deal with the resultant disability. Several contextual factors can influence the recovery process. These factors, internal and external, exist interactively in the lived experiences of the survivors. The limited availability of rehabilitation centres that are located in urban centres meant that recovery predominately occurred outside of the biomedical health and instead relied upon the resources available to individuals and their families.Methods: A qualitative approach with data from in-depth interviews and observations were used to identify contextual factors that shaped recovery following stroke in a community. Twenty-seven individuals with stroke were drawn from a health and demographic surveillance system in Malaysia.Results: Hope and optimism, coping strategies, motivation and support from family and friends, and the use of alternative and complementary medicine shaped the process of recovery within a context where infrastructure is extremely limited.Conclusion: The identification of factors that facilitate the recovery process provides a background in which health care providers can utilise to improve their understanding of the stroke experience. Such understanding could be instrumental in aiding health professionals to offer the most effective help to their clients.Implications for rehabilitationIdentification of contextual factors provides a background for the understanding of the stroke experience.Incorporation of religion into rehabilitation could support and maintain hope in recovery for the survivors and aid acceptance.A collaboration of healthcare professionals with traditional medicine therapists may prove beneficial for the rehabilitation of stroke survivors in Malaysia.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Adaptação Psicológica , Humanos , Malásia , Pesquisa Qualitativa , Sobreviventes
15.
Disabil Rehabil ; 42(1): 102-113, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30183424

RESUMO

Purpose: Stroke is an abrupt event that often leaves survivors with long term disabilities, causing role changes, and financial strains on households. The profound impact of stroke on survivors may lead to a decline in quality of life due to the physical, psychological, and social difficulties they experience. Taking Malaysia as an example, this study aimed to explore the impact of stroke on survivors and how health services influence their recovery in low and middle-income countries (LMIC).Method: An ethnographic approach with data obtained primarily through in-depth interviews was used. Twenty-seven participants identified as having suffered a stroke were drawn from a health and demographic surveillance system in Malaysia.Results: The physical and social disruption of the lives of stroke survivors was intensified by the resultant financial constraints placed upon individuals, families and households, compounded by inadequate support from the health, and welfare systems. Despite the disruption to their lives, most participants were, at least in part, able to reestablish their lives through various factors that include a strong family support and active coping strategies.Conclusion: In LMIC, recovery can be shaped by the family unit and through active coping strategies especially those in relation to spirituality.Implications for rehabilitationThe impact of stroke on survivors and lack of specialized stroke care compromise the recovery process and quality of life for stroke survivors in low and middle-income countries.Support from the family and reinforcement of religious coping were judged to successfully aid recovery.Physical and emotional impairments as well as psychosocial wellbeing of survivors in the context of environmental factors need to be addressed.


Assuntos
Adaptação Psicológica , Pessoas com Deficiência , Qualidade de Vida , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Países em Desenvolvimento , Pessoas com Deficiência/psicologia , Pessoas com Deficiência/reabilitação , Status Econômico , Feminino , Humanos , Malásia/epidemiologia , Masculino , Pessoa de Meia-Idade , Avaliação das Necessidades , Estresse Psicológico/fisiopatologia , Acidente Vascular Cerebral/economia , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/psicologia , Reabilitação do Acidente Vascular Cerebral/métodos , Reabilitação do Acidente Vascular Cerebral/normas
16.
J Fish Biol ; 96(2): 527-532, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31583703

RESUMO

Temperature and sea level are predicted to rise with climate change, bringing an urgency to evaluating future viability of native fish. Lamprey are confronted with widespread habitat degradation, migratory barriers, and episodes of environmental change projected to be commonplace in the future. In California, range contraction likely shifted lamprey rearing downstream, but the extent and physiological constraints that restrict estuarine rearing are unclear. We used a single-season occupancy model to describe juvenile lamprey estuarine distribution and found occupancy was regionally variable and constrained by temperature. Habitat and hydrology providing thermal refugia may be critical for future persistence.


Assuntos
Distribuição Animal , Lampreias/fisiologia , Refúgio de Vida Selvagem , Temperatura , Animais , California , Ecossistema , Estações do Ano
17.
South Afr J HIV Med ; 20(1): 949, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31392036

RESUMO

BACKGROUND: In low- and middle-income countries (LMICs), a substantial unmet need for affordable single-tablet regimen (STR) options remains. Rilpivirine (RPV, TMC278) is formulated in a low-cost STR with tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC). OBJECTIVES: Switching at Low HIV-1 RNA into Fixed Dose Combinations (SALIF) compared RPV with efavirenz (EFV), both as STRs with TDF and FTC, in maintaining virologic suppression. METHODS: SALIF was a phase 3b, randomised, open-label, non-inferiority study in virologically suppressed adults (HIV-1 RNA < 50 copies/mL) on non-nucleoside reverse transcriptase inhibitor (NNRTI)-based first-line antiretroviral therapy (ART) in Cameroon, Kenya, Senegal, South Africa, Uganda and Thailand. Patients (N = 426), stratified by NNRTI use, were randomised 1:1 to receive TDF/FTC/RPV (300/200/25 mg qd) or TDF/FTC/EFV (300/200/600 mg qd). Primary endpoint was proportion of patients with virologic suppression (HIV-1 RNA < 400 copies/mL) at week 48 (intent-to-treat, modified Food and Drug Administration Snapshot, 10% non-inferiority margin). RESULTS: Patients received TDF/FTC/RPV (n = 213) or TDF/FTC/EFV (n = 211). At week 48, virologic suppression was maintained in 200/213 (93.9%) patients in the RPV arm and 203/211 (96.2%) in the EFV arm (difference -2.3%; 95% confidence interval: -6.4, +1.8), demonstrating non-inferiority of TDF/FTC/RPV. One patient in each arm experienced virologic failure without treatment-emergent resistance. Twenty-seven patients discontinued prematurely (8.0% RPV vs. 4.7% EFV), the most frequent reasons being adverse events (3.3% vs. 0.5%, respectively), site closure (1.9% vs. 0.5%), loss to follow-up (0.9% vs. 1.4%) and consent withdrawal (0.9% vs. 1.4%). CONCLUSION: In adults with suppressed viral load on first-line NNRTI-based ART in LMICs, switching to an STR of TDF/FTC/RPV was non-inferior to TDF/FTC/EFV in maintaining high rates of viral suppression with a comparable tolerability profile.

19.
Front Pharmacol ; 10: 667, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31275146

RESUMO

Breast cancer with bone metastasis is essentially incurable with current anticancer therapies. The bone morphogenetic protein (BMP) pathway is an attractive therapeutic candidate, as it is involved in the bone turnover and in cancer cell formation and their colonization of distant organs such as the bone. We previously reported that in breast cancer cells, the ZNF217 oncogene drives BMP pathway activation, increases the metastatic growth rate in the bone, and accelerates the development of severe osteolytic lesions in mice. In the present study, we aimed at investigating the impact of the LDN-193189 compound, a potent inhibitor of the BMP type I receptor, on metastasis development in vivo. ZNF217-revLuc cells were injected into the left ventricle of nude mice (n = 16) while control mice (n = 13) were inoculated with control pcDNA6-revLuc cells. Mice from each group were treated or not with LDN-193189 for 35 days. We found that systemic LDN-193189 treatment of mice significantly enhanced metastasis development, by increasing both the number and the size of metastases. In pcDNA6-revLuc-injected mice, LDN-193189 also affected the kinetics of metastasis emergence. Altogether, these data suggest that in vivo, LDN-193189 might affect the interaction between breast cancer cells and the bone environment, favoring the emergence and development of multiple metastases. Hence, our report highlights the importance of the choice of drugs and therapeutic strategies used in the management of bone metastases.

20.
Int J Mol Sci ; 20(11)2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31195751

RESUMO

Endocrine therapies targeting oestrogen signalling have significantly improved breast cancer management. However, their efficacy is limited by intrinsic and acquired resistance to treatment, which remains a major challenge for oestrogen receptor α (ERα)-positive tumours. Though many studies using in vitro models of endocrine resistance have identified putative actors of resistance, no consensus has been reached. We demonstrated previously that oestrogen non-genomic signalling, characterized by the formation of the ERα/Src/PI3K complex, is activated in aggressive breast cancers (BC). We wondered herein whether the activation of this pathway is also involved in resistance to endocrine therapies. We studied the interactions between ERα and Src or PI3K by proximity ligation assay (PLA) in in-vitro and in-vivo endocrine therapy-resistant breast cancer models. We reveal an increase in ERα/Src and ERα/PI3K interactions in patient-derived xenografts (PDXs) with acquired resistance to tamoxifen, as well as in tamoxifen-resistant MCF-7 cells compared to parental counterparts. Moreover, no interactions were observed in breast cancer cells resistant to other endocrine therapies. Finally, the use of a peptide inhibiting the ERα-Src interaction partially restored tamoxifen sensitivity in resistant cells, suggesting that such components could constitute promising targets to circumvent resistance to tamoxifen in BC.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Estrogênios/farmacologia , Transdução de Sinais , Tamoxifeno/farmacologia , Animais , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Células MCF-7 , Camundongos Nus , Fosfatidilinositol 3-Quinases/metabolismo , Quinases da Família src/metabolismo
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