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1.
Bioinformatics ; 39(1)2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36629453

RESUMO

MOTIVATION: Nowadays, epigenetic gene regulations are studied in each part of the biology, from embryonic development to diseases such as cancers and neurodegenerative disorders. Currently, to quantify and compare CpG methylation levels of a specific region of interest, the most accessible technique is the bisulfite sequencing PCR (BSP). However, no existing user-friendly tool is able to analyze data from all approaches of BSP. Therefore, the most convenient way to process results from the direct sequencing of PCR products (direct-BSP) is to manually analyze the chromatogram traces, which is a repetitive and prone to error task. RESULTS: Here, we implement a new R-based tool, called ABSP for analysis of bisulfite sequencing PCR, providing a complete analytic process of both direct-BSP and cloning-BSP data. It uses the raw sequencing trace files (.ab1) as input to compute and compare CpG methylation percentages. It is fully automated and includes a user-friendly interface as a built-in R shiny app, quality control steps and generates publication-ready graphics. AVAILABILITY AND IMPLEMENTATION: The ABSP tool and associated data are available on GitHub at https://github.com/ABSP-methylation-tool/ABSP. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Metilação de DNA , Sulfitos , Análise de Sequência de DNA/métodos , Reação em Cadeia da Polimerase/métodos , Software
2.
Int J Mol Sci ; 24(3)2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36768643

RESUMO

Polycomb group (PcG) proteins are highly conserved proteins assembled into two major types of complexes, PRC1 and PRC2, involved in the epigenetic silencing of a wide range of gene expression programs regulating cell fate and tissue development. The crucial role of PRC1 and PRC2 in the fundamental cellular processes and their involvement in human pathologies such as cancer attracted intense attention over the last few decades. Here, we review recent advancements regarding PRC1 and PRC2 function using the zebrafish model. We point out that the unique characteristics of the zebrafish model provide an exceptional opportunity to increase our knowledge of the role of the PRC1 and PRC2 complexes in tissue development, in the maintenance of organ integrity and in pathology.


Assuntos
Proteínas de Drosophila , Peixe-Zebra , Animais , Humanos , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas do Grupo Polycomb/genética , Proteínas do Grupo Polycomb/metabolismo , Epigênese Genética , Proteínas de Drosophila/metabolismo , Complexo Repressor Polycomb 1/metabolismo
3.
Int J Mol Sci ; 23(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36555673

RESUMO

Prostate cancer is a major public health concern and one of the most prevalent forms of cancer worldwide. The definition of altered signaling pathways implicated in this complex disease is thus essential. In this context, abnormal expression of the receptor of Macrophage Colony-Stimulating Factor-1 (M-CSF or CSF-1) has been described in prostate cancer cells. Yet, outcomes of this expression remain unknown. Using mouse and human prostate cancer cell lines, this study has investigated the functionality of the wild-type CSF-1 receptor in prostate tumor cells and identified molecular mechanisms underlying its ligand-induced activation. Here, we showed that upon CSF-1 binding, the receptor autophosphorylates and activates multiple signaling pathways in prostate tumor cells. Biological experiments demonstrated that the CSF-1R/CSF-1 axis conferred significant advantages in cell growth and cell invasion in vitro. Mouse xenograft experiments showed that CSF-1R expression promoted the aggressiveness of prostate tumor cells. In particular, we demonstrated that the ligand-activated CSF-1R increased the expression of spp1 transcript encoding for osteopontin, a key player in cancer development and metastasis. Therefore, this study highlights that the CSF-1 receptor is fully functional in a prostate cancer cell and may be a potential therapeutic target for the treatment of prostate cancer.


Assuntos
Osteopontina , Neoplasias da Próstata , Receptor de Fator Estimulador de Colônias de Macrófagos , Animais , Humanos , Masculino , Camundongos , Ligantes , Fator Estimulador de Colônias de Macrófagos/metabolismo , Osteopontina/genética , Neoplasias da Próstata/metabolismo , Receptor de Fator Estimulador de Colônias de Macrófagos/genética , Receptor de Fator Estimulador de Colônias de Macrófagos/metabolismo
4.
Cell Mol Life Sci ; 76(23): 4673-4687, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31338555

RESUMO

Cancer cells exhibit hallmarks in terms of proliferation, resistance to cell death, angiogenesis, invasion, metastasis, and genomic instability. Despite the progress in cancer research and the comprehension of tumorigenesis mechanisms, cancer remains a major issue in public health. A better understanding of the molecular factors associated with the appearance or progression of cancer may allow the development of therapeutic alternatives. Increasing data highlight the role of long non-coding RNAs in many diseases, including cancer. The long non-coding RNA H19 was the first discovered riboregulator, and it has been shown to be involved at multiple steps of tumorigenesis. Indeed, this lncRNA exert its action at various molecular scales. Understanding the role of H19 in cancer progression may allow to set up therapeutic strategies to prevent tumor expansion and metastatic dissemination. In this review, we will summarize the overexpression of the long non-coding RNA H19 in several types of cancer and the multiple implications of the long non-coding RNA H19 in the different hallmarks that define human cancer.


Assuntos
Neoplasias/patologia , RNA Longo não Codificante/metabolismo , Apoptose/genética , Carcinogênese/genética , Transição Epitelial-Mesenquimal , Humanos , MicroRNAs/metabolismo , Neoplasias/irrigação sanguínea , Neoplasias/genética , Neovascularização Patológica , Interferência de RNA , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/genética , Proteína Supressora de Tumor p53/metabolismo
5.
Vet Pathol ; 57(4): 507-519, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32351171

RESUMO

Accumulating data highlight the role of neurotrophins and their receptors in human breast cancer. This family includes nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), both synthetized as proneurotrophins (proNGF and proBDNF). (pro)NGF and (pro)BDNF initiate their biological effects by binding to both their specific receptors TrkA and TrkB, respectively, and the common receptor p75NTR. Currently, no data are available about their expression and potential role in canine mammary tumors. The aim of this study was to investigate expression of proNGF and BDNF as well as their receptors TrkA, TrkB, and p75NTR in canine mammary carcinomas, and to correlate them with clinicopathological parameters (grade, histological type, lymph node status, recurrence, and distant metastasis) and survival. Immunohistochemistry was performed on serial sections of 96 canine mammary carcinomas with antibodies against proNGF, BDNF, TrkA, TrkB, and p75NTR. Of the 96 carcinomas, proNGF expression was detected in 71 (74%), BDNF in 79 (82%), TrkA in 94 (98%), TrkB in 35 (37%), and p75NTR in 44 (46%). No association was observed between proNGF, BDNF, or TrkA expression and either clinicopathological parameters or survival. TrkB and p75NTR expression were associated with favorable clinicopathological parameters as well as better overall survival.


Assuntos
Doenças do Cão/patologia , Neoplasias Mamárias Animais , Fatores de Crescimento Neural/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Cães , Imuno-Histoquímica/veterinária , Linfonodos/patologia , Neoplasias Mamárias Animais/diagnóstico , Neoplasias Mamárias Animais/metabolismo , Neoplasias Mamárias Animais/patologia , Gradação de Tumores , Metástase Neoplásica/patologia , Recidiva Local de Neoplasia/veterinária , Fator de Crescimento Neural/metabolismo , Prognóstico , Receptor de Fator de Crescimento Neural/metabolismo , Receptor trkA/metabolismo , Receptor trkB/metabolismo
6.
Proteomics ; 19(21-22): e1800454, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31430054

RESUMO

Many solid cancers are hierarchically organized with a small number of cancer stem cells (CSCs) able to regrow a tumor, while their progeny lacks this feature. Breast CSC is known to contribute to therapy resistance. The study of those cells is usually based on their cell-surface markers like CD44high /CD24low/neg or their aldehyde dehydrogenase (ALDH) activity. However, these markers cannot be used to track the dynamics of CSC. Here, a transcriptomic analysis is performed to identify segregating gene expression in CSCs and non-CSCs, sorted by Aldefluor assay. It is observed that among ALDH-associated genes, only ALDH1A1 isoform is increased in CSCs. A CSC reporter system is then developed by using a far red-fluorescent protein (mNeptune) under the control of ALDH1A1 promoter. mNeptune-positive cells exhibit higher sphere-forming capacity, tumor formation, and increased resistance to anticancer therapies. These results indicate that the reporter identifies cells with stemness characteristics. Moreover, live tracking of cells in a microfluidic system reveals a higher extravasation potential of CSCs. Live tracking of non-CSCs under irradiation treatment show, for the first time, live reprogramming of non-CSCs into CSCs. Therefore, the reporter will allow for cell tracking to better understand the implication of CSCs in breast cancer development and recurrence.


Assuntos
Família Aldeído Desidrogenase 1/genética , Neoplasias da Mama/genética , Rastreamento de Células , Perfilação da Expressão Gênica , Genes Reporter , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Retinal Desidrogenase/genética , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Reprogramação Celular/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genoma Humano , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos Endogâmicos NOD , Camundongos SCID , Células-Tronco Neoplásicas/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Reprodutibilidade dos Testes
7.
Vet Pathol ; 56(3): 377-388, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30558511

RESUMO

CD44+/CD24- phenotype has been used to identify human and canine mammary cancer stem-like cells. In canine mammary tumors, CD44+/CD24- phenotype has been associated with high grade and lymph node infiltration. However, several studies have reported opposing results regarding the clinical significance of phenotypic groups formed by the combination of CD44 and CD24 in both human and canine mammary tumors. So far, no study has investigated the correlation between these phenotypes and survival in dogs. The aim of this study was to investigate the expression and distribution of CD44 and CD24 in canine mammary carcinomas and to correlate them with histological diagnosis and survival in a well-characterized cohort. Immunohistochemistry was performed in 96 mammary carcinomas with antibodies against CD44 and CD24. Expression of CD44+ and CD44+/CD24- phenotype was detected in 75 of 96 (78%) and 63 of 96 (65.6%) carcinomas, respectively. Their expression was associated with tumor type, occurring more often in tubular complex carcinomas than in solid carcinomas. CD44+/CD24- phenotype was associated with a better overall survival ( P = .001). CD24+ expression was detected in 52 of 96 tumors (54%) and CD44-/CD24+ phenotype in 39 of 96 tumors (40.6%). Both were associated with poor clinicopathological parameters (high grade, and emboli). No correlation with overall survival was observed. CD44+/CD24- expression was associated with a better prognosis and occurred at high frequency and high level, indicating that this phenotype is not suitable to detect cancer stem cells in canine mammary carcinomas. Although further studies are needed, our results suggest that CD24 may constitute a valuable marker of poor prognosis for canine mammary carcinomas.


Assuntos
Antígeno CD24/metabolismo , Doenças do Cão/diagnóstico , Receptores de Hialuronatos/metabolismo , Neoplasias Mamárias Animais/diagnóstico , Animais , Doenças do Cão/metabolismo , Doenças do Cão/mortalidade , Doenças do Cão/patologia , Cães , Feminino , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/patologia , Neoplasias Mamárias Animais/metabolismo , Neoplasias Mamárias Animais/mortalidade , Neoplasias Mamárias Animais/patologia , Prognóstico
8.
Cell Mol Life Sci ; 73(9): 1859-70, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26883804

RESUMO

Cancer stem cells (CSCs), are thought to be at the origin of tumor development and resistance to therapies. Thus, a better understanding of the molecular mechanisms involved in the control of CSC stemness is essential to the design of more effective therapies for cancer patients. Cancer cell stemness and the subsequent expansion of CSCs are regulated by micro-environmental signals including neurotrophins. Over the years, the roles of neurotrophins in tumor development have been well established and regularly reviewed. Especially, nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) are reported to stimulate tumor cell proliferation, survival, migration and/or invasion, and favors tumor angiogenesis. More recently, neurotrophins have been reported to regulate CSCs. This review briefly presents neurotrophins and their receptors, summarizes their roles in different cancers, and discusses the emerging evidence of neurotrophins-induced enrichment of CSCs as well as the involved signaling pathways.


Assuntos
Células-Tronco Neoplásicas/metabolismo , Fatores de Crescimento Neural/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Transição Epitelial-Mesenquimal , Humanos , Células-Tronco Neoplásicas/citologia , Receptores de Fator de Crescimento Neural/metabolismo , Transdução de Sinais
9.
Int J Mol Sci ; 18(11)2017 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-29099749

RESUMO

Breast cancer is one of the most common causes of cancer related deaths in women. Despite the progress in early detection and use of new therapeutic targets associated with development of novel therapeutic options, breast cancer remains a major problem in public health. Indeed, even if the survival rate has improved for breast cancer patients, the number of recurrences within five years and the five-year relative survival rate in patients with metastasis remain dramatic. Thus, the discovery of new molecular actors involved in breast progression is essential to improve the management of this disease. Numerous data indicate that long non-coding RNA are implicated in breast cancer development. The oncofetal lncRNA H19 was the first RNA identified as a riboregulator. Studying of this lncRNA revealed its implication in both normal development and diseases. In this review, we summarize the different mechanisms of action of H19 in human breast cancer.


Assuntos
Neoplasias da Mama/genética , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , RNA Longo não Codificante/genética , Animais , Mama/metabolismo , Mama/patologia , Neoplasias da Mama/patologia , Ciclo Celular , Feminino , Loci Gênicos , Humanos
10.
Stem Cells ; 33(2): 342-53, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25286822

RESUMO

The discovery of cancer stem cells (CSCs) fundamentally advanced our understanding of the mechanisms governing breast cancer development. However, the stimuli that control breast CSC self-renewal and differentiation have still not been fully detailed. We previously showed that nerve growth factor (NGF) and its precursor proNGF can stimulate breast cancer cell growth and invasion in an autocrine manner. In this study, we investigated the effects of NGF and proNGF on the breast CSC compartment and found that NGF or proNGF enrich for CSCs in several breast cancer cell lines. This enrichment appeared to be achieved by increasing the number of symmetric divisions of quiescent/slow-proliferating CSCs. Interestingly, in vitro NGF pretreatment of MCF-7 luminal breast cancer cells promoted epithelial to mesenchymal transition in tumors of severe combined immunodeficient mice. Furthermore, p75(NTR), the common receptor for both neurotrophins and proneurotrophins, mediated breast CSC self-renewal by regulating the expression of pluripotency transcription factors. Our data indicate, for the first time, that the NGF/proNGF/p75(NTR) axis plays a critical role in regulating breast CSC self-renewal and plasticity.


Assuntos
Comunicação Autócrina , Neoplasias da Mama/metabolismo , Proliferação de Células , Transição Epitelial-Mesenquimal , Proteínas de Neoplasias/metabolismo , Células-Tronco Neoplásicas/metabolismo , Fator de Crescimento Neural/metabolismo , Precursores de Proteínas/metabolismo , Nicho de Células-Tronco , Animais , Neoplasias da Mama/patologia , Feminino , Humanos , Camundongos , Camundongos SCID , Invasividade Neoplásica , Células-Tronco Neoplásicas/patologia , Proteínas do Tecido Nervoso/metabolismo , Receptores de Fator de Crescimento Neural/metabolismo
11.
Cell Mol Life Sci ; 71(13): 2467-81, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24481864

RESUMO

p75(NTR), the common receptor for both neurotrophins and proneurotrophins, has been widely studied because of its role in many tissues, including the nervous system. More recently, a close relationship between p75(NTR) expression and pluripotency has been described. p75(NTR) was shown to be expressed in various types of stem cells and has been used to prospectively isolate stem cells with different degrees of potency. Here, we give an overview of the current knowledge on p75(NTR) in stem cells, ranging from embryonic to adult stem cells, and cancer stem cells. In an attempt to address its potential role in the control of stem cell biology, the molecular mechanisms underlying p75(NTR) signaling in different models are also highlighted. p75(NTR)-mediated functions include survival, apoptosis, migration, and differentiation, and depend on cell type, (pro)neurotrophin binding, interacting transmembrane co-receptors expression, intracellular adaptor molecule availability, and post-translational modifications, such as regulated proteolytic processing. It is therefore conceivable that p75(NTR) can modulate cell-fate decisions through its highly ramified signaling pathways. Thus, elucidating the potential implications of p75(NTR) activity as well as the underlying molecular mechanisms of p75(NTR) will shed new light on the biology of both normal and cancer stem cells.


Assuntos
Marcadores Genéticos , Proteínas do Tecido Nervoso/genética , Células-Tronco Pluripotentes/metabolismo , Receptores de Fator de Crescimento Neural/genética , Pesquisa com Células-Tronco , Apoptose/genética , Diferenciação Celular/genética , Movimento Celular/genética , Humanos , Células-Tronco Neoplásicas/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores de Fator de Crescimento Neural/metabolismo , Transdução de Sinais
12.
J Biol Chem ; 287(3): 1923-31, 2012 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-22128158

RESUMO

The precursor of nerve growth factor (proNGF) has been described as a biologically active polypeptide able to induce apoptosis in neuronal cells, via the neurotrophin receptor p75(NTR) and the sortilin receptor. Herein, it is shown that proNGF is produced and secreted by breast cancer cells, stimulating their invasion. Using Western blotting and mass spectrometry, proNGF was detected in a panel of breast cancer cells as well as in their conditioned media. Immunohistochemical analysis indicated an overproduction of proNGF in breast tumors, when compared with benign and normal breast biopsies, and a relationship to lymph node invasion in ductal carcinomas. Interestingly, siRNA against proNGF induced a decrease of breast cancer cell invasion that was restored by the addition of non-cleavable proNGF. The activation of TrkA, Akt, and Src, but not the MAP kinases, was observed. In addition, the proNGF invasive effect was inhibited by the Trk pharmacological inhibitor K252a, a kinase-dead TrkA, and siRNA against TrkA sortilin, neurotensin, whereas siRNA against p75(NTR) and the MAP kinase inhibitor PD98059 had no impact. These data reveal the existence of an autocrine loop stimulated by proNGF and mediated by TrkA and sortilin, with the activation of Akt and Src, for the stimulation of breast cancer cell invasion.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Comunicação Autócrina , Neoplasias da Mama/metabolismo , Carcinoma Ductal/metabolismo , Fator de Crescimento Neural/metabolismo , Precursores de Proteínas/metabolismo , Receptor trkA/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/genética , Biópsia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carbazóis/farmacologia , Carcinoma Ductal/genética , Carcinoma Ductal/patologia , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/genética , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Alcaloides Indólicos/farmacologia , Metástase Linfática , Invasividade Neoplásica , Fator de Crescimento Neural/genética , Precursores de Proteínas/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor trkA/genética , Receptores de Fator de Crescimento Neural/genética , Receptores de Fator de Crescimento Neural/metabolismo , Quinases da Família src/genética , Quinases da Família src/metabolismo
13.
Front Oncol ; 13: 661775, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37576898

RESUMO

Head and Neck Squamous Cell Carcinoma (HNSCC) remains a cancer with a poor prognosis, with a 5-year survival rate of less than 50%. Although epidermal growth factor receptor (EGFR) is almost always overexpressed, targeted anti-EGFR therapies have modest efficacy and are mainly used in palliative care. Growth factors such as Nerve Growth Factor (NGF) and its precursor proNGF have been shown in our laboratory to play a role in tumor growth and aggressiveness. Interestingly, an interaction between Sortilin, a proNGF receptor, and EGFR has been observed. This interaction appears to interfere with the pro-oncogenic signaling of EGF and modulate the membrane expression of EGFR. The aim of this study was to characterize this interaction biologically, to assess its impact on clinical prognosis and to analyze its role in the cellular trafficking of EGFR. Using immunohistochemical staining on tumor sections from patients treated at our university center and PLA (Proximity Ligation Assay) labeling, we showed that Sortilin expression is significantly associated with reduced 5-year survival. However, when Sortilin was associated with EGFR, this association was not found. Using the Cal-27 and Cal-33 cancer cell lines, we observed that proNGF reduces the effects of EGF on cell growth by inducing the internalization of its receptor. These results therefore suggest a regulatory role for Sortilin in the degradation or renewal of EGFR on the membrane. It would be interesting in future work to show the intracellular fate of EGFR and the role of (pro)neurotrophins in these mechanisms.

14.
Neoplasia ; 46: 100949, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37956532

RESUMO

Triple negative breast cancer (TNBC) is an aggressive malignancy for which chemotherapy remains the standard treatment. However, between 3 and 5 years after chemotherapy, about half patients will relapse and it is essential to identify vulnerabilities of cancer cells surviving neoadujuvant therapy. In this study, we established persistent TNBC cell models after treating MDA-MB-231 and SUM159-PT TNBC cell lines with epirubicin and cyclophosphamide, and then with paclitaxel, for a total of 18 weeks. The resulting chemo-persistent cell lines were more proliferative, both in vitro and in xenografted mice. Interestingly, MDA-MB-231 persistent cells became less sensitive to chemotherapeutic drugs, whereas SUM159-PT persistent cells kept similar sensitivity compared to control cells. The reduced sensitivity to chemotherapy in MDA-MB-231 persistent cells was found to be associated with an increased oxidative phosphorylation (OXPHOS) and modified levels of tricarboxylic acid cycle (TCA) intermediates. Integration of data from proteomics and metabolomics demonstrated TCA cycle among the most upregulated pathways in MDA-MB-231 persistent cells. The absence of glucose and pyruvate impeded OXPHOS in persistent cells, while the absence of glutamine did not. In contrast, OXPHOS was not modified in control cells independently of TCA substrates, indicating that MDA-MB-231 persistent cells evolved towards a more pyruvate dependent profile. Finally, the inhibition of pyruvate entry into mitochondria with UK-5099 reduced OXPHOS and re-sensitized persistent cells to therapeutic agents. Together, these findings suggest that targeting mitochondrial pyruvate metabolism may help to overcome mitochondrial adaptation of chemo-persistent TNBC.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Neoplasias de Mama Triplo Negativas/patologia , Linhagem Celular Tumoral , Paclitaxel/farmacologia , Mitocôndrias/metabolismo , Piruvatos , Proliferação de Células
15.
Exp Hematol Oncol ; 12(1): 104, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38072918

RESUMO

BACKGROUND: Triple-Negative Breast Cancer is particularly aggressive, and its metastasis to the brain has a significant psychological impact on patients' quality of life, in addition to reducing survival. The development of brain metastases is particularly harmful in triple-negative breast cancer (TNBC). To date, the mechanisms that induce brain metastasis in TNBC are poorly understood. METHODS: Using a human blood-brain barrier (BBB) in vitro model, an in vitro 3D organotypic extracellular matrix, an ex vivo mouse brain slices co-culture and in an in vivo xenograft experiment, key step of brain metastasis were recapitulated to study TNBC behaviors. RESULTS: In this study, we demonstrated for the first time the involvement of the precursor of Nerve Growth Factor (proNGF) in the development of brain metastasis. More importantly, our results showed that proNGF acts through TrkA independent of its phosphorylation to induce brain metastasis in TNBC. In addition, we found that proNGF induces BBB transmigration through the TrkA/EphA2 signaling complex. More importantly, our results showed that combinatorial inhibition of TrkA and EphA2 decreased TBNC brain metastasis in a preclinical model. CONCLUSIONS: These disruptive findings provide new insights into the mechanisms underlying brain metastasis with proNGF as a driver of brain metastasis of TNBC and identify TrkA/EphA2 complex as a potential therapeutic target.

16.
Glycobiology ; 22(6): 806-16, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22301273

RESUMO

We have recently established and characterized cellular clones deriving from MDA-MB-231 breast cancer cells that express the human G(D3) synthase (GD3S), the enzyme that controls the biosynthesis of b- and c-series gangliosides. The GD3S positive clones show a proliferative phenotype in the absence of serum or growth factors and an increased tumor growth in severe immunodeficient mice. This phenotype results from the constitutive activation of the receptor tyrosine kinase c-Met in spite of the absence of ligand and subsequent activation of mitogen-activated protein kinase/extracellular signal-regulated kinase and phosphoinositide 3-kinase/Akt pathways. Here, we show by mass spectrometry analysis of total glycosphingolipids that G(D3) and G(D2) are the main gangliosides expressed by the GD3S positive clones. Moreover, G(D2) colocalized with c-Met at the plasma membrane and small interfering RNA silencing of the G(M2)/G(D2) synthase efficiently reduced the expression of G(D2) as well as c-Met phosphorylation and reversed the proliferative phenotype. Competition assays using anti-G(D2) monoclonal antibodies also inhibit proliferation and c-Met phosphorylation of GD3S positive clones in serum-free conditions. Altogether, these results demonstrate the involvement of the disialoganglioside G(D2) in MDA-MB-231 cell proliferation via the constitutive activation of c-Met. The accumulation of G(D2) in c-Met expressing cells could therefore reinforce the tumorigenicity and aggressiveness of breast cancer tumors.


Assuntos
Neoplasias da Mama/metabolismo , Gangliosídeos/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Sialiltransferases/genética , Anticorpos Monoclonais/farmacologia , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Membrana Celular/química , Membrana Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Gangliosídeos/análise , Humanos , Espectrometria de Massas , Fenótipo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Interferência de RNA , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/farmacologia , Sialiltransferases/metabolismo , Células Tumorais Cultivadas
17.
Molecules ; 17(8): 9559-72, 2012 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-22885356

RESUMO

Glycosphingolipids from the ganglio-series are usually classified in four series according to the presence of 0 to 3 sialic acid residues linked to lactosylceramide. The transfer of sialic acid is catalyzed in the Golgi apparatus by specific sialyltransferases that show high specificity toward glycolipid substrates. ST8Sia I (EC 2.4.99.8, SAT-II, SIAT 8a) is the key enzyme controlling the biosynthesis of b- and c-series gangliosides. ST8Sia I is expressed at early developmental stages whereas in adult human tissues, ST8Sia I transcripts are essentially detected in brain. ST8Sia I together with b- and c-series gangliosides are also over-expressed in neuroectoderm-derived malignant tumors such as melanoma, glioblastoma, neuroblastoma and in estrogen receptor (ER) negative breast cancer, where they play a role in cell proliferation, migration, adhesion and angiogenesis. We have stably expressed ST8Sia I in MCF-7 breast cancer cells and analyzed the glycosphingolipid composition of wild type (WT) and GD3S+ clones. As shown by mass spectrometry, MCF-7 expressed a complex pattern of neutral and sialylated glycosphingolipids from globo- and ganglio-series. WT MCF-7 cells exhibited classical monosialylated gangliosides including G(M3), G(M2), and G(M1a). In parallel, the expression of ST8Sia I in MCF-7 GD3S+ clones resulted in a dramatic change in ganglioside composition, with the expression of b- and c-series gangliosides as well as unusual tetra- and pentasialylated lactosylceramide derivatives G(Q3) (II(3)Neu5Ac(4)-Gg(2)Cer) and G(P3) (II(3)Neu5Ac(5)-Gg(2)Cer). This indicates that ST8Sia I is able to act as an oligosialyltransferase in a cellular context.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Gangliosídeos/metabolismo , Expressão Gênica , Sialiltransferases/genética , Sialiltransferases/metabolismo , Feminino , Gangliosídeos/biossíntese , Glicoesfingolipídeos/metabolismo , Humanos , Células MCF-7 , Metilação
18.
J Exp Clin Cancer Res ; 41(1): 110, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35346305

RESUMO

BACKGROUND: CD44 is a multifunctional membrane glycoprotein. Through its heparan sulfate chain, CD44 presents growth factors to their receptors. We have shown that CD44 and Tropomyosin kinase A (TrkA) form a complex following nerve growth factor (NGF) induction. Our study aimed to understand how CD44 and TrkA interact and the consequences of inhibiting this interaction regarding the pro-tumoral effect of NGF in breast cancer. METHODS: After determining which CD44 isoforms (variants) are involved in forming the TrkA/CD44 complex using proximity ligation assays, we investigated the molecular determinants of this interaction. By molecular modeling, we isolated the amino acids involved and confirmed their involvement using mutations. A CD44v3 mimetic peptide was then synthesized to block the TrkA/CD44v3 interaction. The effects of this peptide on the growth, migration and invasion of xenografted triple-negative breast cancer cells were assessed. Finally, we investigated the correlations between the expression of the TrkA/CD44v3 complex in tumors and histo-pronostic parameters. RESULTS: We demonstrated that isoform v3 (CD44v3), but not v6, binds to TrkA in response to NGF stimulation. The final 10 amino acids of exon v3 and the TrkA H112 residue are necessary for the association of CD44v3 with TrkA. Functionally, the CD44v3 mimetic peptide impairs not only NGF-induced RhoA activation, clonogenicity, and migration/invasion of breast cancer cells in vitro but also tumor growth and metastasis in a xenograft mouse model. We also detected TrkA/CD44v3 only in cancerous cells, not in normal adjacent tissues. CONCLUSION: Collectively, our results suggest that blocking the CD44v3/TrkA interaction can be a new therapeutic option for triple-negative breast cancers.


Assuntos
Neoplasias da Mama , Receptores de Hialuronatos , Fator de Crescimento Neural , Receptor trkA , Animais , Neoplasias da Mama/genética , Feminino , Humanos , Receptores de Hialuronatos/metabolismo , Camundongos , Fator de Crescimento Neural/farmacologia , Isoformas de Proteínas , Receptor trkA/metabolismo
19.
Cells ; 10(11)2021 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-34831364

RESUMO

Polycomb repressive complex 2 (PRC2) mediates histone H3K27me3 methylation and the stable transcriptional repression of a number of gene expression programs involved in the control of cellular identity during development and differentiation. Here, we report on the generation and on the characterization of a zebrafish line harboring a null allele of eed, a gene coding for an essential component of the PRC2. Homozygous eed-deficient mutants present a normal body plan development but display strong defects at the level of the digestive organs, such as reduced size of the pancreas, hepatic steatosis, and a loss of the intestinal structures, to die finally at around 10-12 days post fertilization. In addition, we found that PRC2 loss of function impairs neuronal differentiation in very specific and discrete areas of the brain and increases larval activity in locomotor assays. Our work highlights that zebrafish is a suited model to study human pathologies associated with PRC2 loss of function and H3K27me3 decrease.


Assuntos
Sistema Digestório/metabolismo , Homeostase , Neurônios/citologia , Complexo Repressor Polycomb 2/deficiência , Peixe-Zebra/metabolismo , Animais , Animais Geneticamente Modificados , Comportamento Animal , Diferenciação Celular , Regulação da Expressão Gênica no Desenvolvimento , Histonas/metabolismo , Larva/metabolismo , Fígado/metabolismo , Lisina/metabolismo , Metilação , Atividade Motora , Mutação/genética , Neurônios/metabolismo , Especificidade de Órgãos , Complexo Repressor Polycomb 2/metabolismo , Processamento de Proteína Pós-Traducional , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Nucleases dos Efetores Semelhantes a Ativadores de Transcrição/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
20.
Cancers (Basel) ; 13(8)2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33918823

RESUMO

Hypoxia is a hallmark of many solid tumors and is associated with resistance to anticancer treatments. Hypoxia-activated prodrugs (HAPs) were developed to target the hypoxic regions of these tumors. Among 2nd generation HAPs, Evofosfamide (Evo, also known as TH-302) exhibits preclinical and clinical activities against adult glioblastoma. In this study, we evaluated its potential in the field of pediatric neuro-oncology. We assessed the efficacy of Evo in vitro as a single drug, or in combination with SN38, doxorubicin, and etoposide, against three pediatric high-grade glioma (pHGG) and three diffuse intrinsic pontine glioma (DIPG) cell lines under hypoxic conditions. We also investigated radio-sensitizing effects using clonogenic assays. Evo inhibited the growth of all cell lines, mainly under hypoxia. We also highlighted a significant synergism between Evo and doxorubicin, SN38, or etoposide. Finally, Evo radio-sensitized the pHGG cell line tested, both with fractionated and single-dose irradiation schedules. Altogether, we report here the first preclinical proof of evidence about Evofosfamide efficiency against hypoxic pHGG and DIPG cells. Since such tumors are highly hypoxic, and Evo potentiates the effect of ionizing radiation and chemotherapy, it appears as a promising therapeutic strategy for children with brain tumors.

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