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1.
Cell Death Dis ; 14(2): 133, 2023 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-36797240

RESUMO

Polo-like kinase 4 (Plk4), the major regulator of centriole biogenesis, has emerged as a putative therapeutic target in cancer due to its abnormal expression in human carcinomas, leading to centrosome number deregulation, mitotic defects and chromosomal instability. Moreover, Plk4 deregulation promotes tumor growth and metastasis in mouse models and is significantly associated with poor patient prognosis. Here, we further investigate the role of Plk4 in carcinogenesis and show that its overexpression significantly potentiates resistance to cell death by anoikis of nontumorigenic p53 knock-out (p53KO) mammary epithelial cells. Importantly, this effect is independent of Plk4's role in centrosome biogenesis, suggesting that this kinase has additional cellular functions. Interestingly, the Plk4-induced anoikis resistance is associated with the induction of a stable hybrid epithelial-mesenchymal phenotype and is partially dependent on P-cadherin upregulation. Furthermore, we found that the conditioned media of Plk4-induced p53KO mammary epithelial cells also induces anoikis resistance of breast cancer cells in a paracrine way, being also partially dependent on soluble P-cadherin secretion. Our work shows, for the first time, that high expression levels of Plk4 induce anoikis resistance of both mammary epithelial cells with p53KO background, as well as of breast cancer cells exposed to their secretome, which is partially mediated through P-cadherin upregulation. These results reinforce the idea that Plk4, independently of its role in centrosome biogenesis, functions as an oncogene, by impacting the tumor microenvironment to promote malignancy.


Assuntos
Neoplasias da Mama , Proteína Supressora de Tumor p53 , Animais , Feminino , Humanos , Camundongos , Anoikis , Neoplasias da Mama/genética , Células Epiteliais , Fenótipo , Proteínas Serina-Treonina Quinases/genética , Microambiente Tumoral , Proteína Supressora de Tumor p53/genética , Transição Epitelial-Mesenquimal
2.
Dis Model Mech ; 16(2)2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36808468

RESUMO

Alterations in the expression or function of cell adhesion molecules have been implicated in all steps of tumor progression. Among those, P-cadherin is highly enriched in basal-like breast carcinomas, playing a central role in cancer cell self-renewal, collective cell migration and invasion. To establish a clinically relevant platform for functional exploration of P-cadherin effectors in vivo, we generated a humanized P-cadherin Drosophila model. We report that actin nucleators, Mrtf and Srf, are main P-cadherin effectors in fly. We validated these findings in a human mammary epithelial cell line with conditional activation of the SRC oncogene. We show that, prior to promoting malignant phenotypes, SRC induces a transient increase in P-cadherin expression, which correlates with MRTF-A accumulation, its nuclear translocation and the upregulation of SRF target genes. Moreover, knocking down P-cadherin, or preventing F-actin polymerization, impairs SRF transcriptional activity. Furthermore, blocking MRTF-A nuclear translocation hampers proliferation, self-renewal and invasion. Thus, in addition to sustaining malignant phenotypes, P-cadherin can also play a major role in the early stages of breast carcinogenesis by promoting a transient boost of MRTF-A-SRF signaling through actin regulation.


Assuntos
Actinas , Transativadores , Humanos , Actinas/metabolismo , Transativadores/metabolismo , Transdução de Sinais , Caderinas , Células Epiteliais/metabolismo , Fator de Resposta Sérica/genética , Fator de Resposta Sérica/metabolismo
3.
Methods Mol Biol ; 2572: 155-166, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36161415

RESUMO

The chick embryo chorioallantoic membrane (CAM), an extensively vascularized extraembryonic membrane, has been widely used to study several aspects of tumor development including tumor-induced angiogenesis, tumor cell proliferation, and metastasis. Based on the tumor cell/CAM system, we focused here on the identification and quantification of cancer stem cells. We validated the CAM model as a suitable model to evaluate stem cell activity in a given mixed cell population.


Assuntos
Membrana Corioalantoide , Neoplasias , Animais , Embrião de Galinha , Galinhas , Humanos , Neovascularização Patológica , Células-Tronco
4.
Biology (Basel) ; 11(7)2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-36101425

RESUMO

Transitions between epithelial and mesenchymal cellular states (EMT/MET) contribute to cancer progression. We hypothesize that EMT followed by MET promotes cell population heterogeneity, favouring tumour growth. We developed an EMT model by on and off exposure of epithelial EpH4 cells (E-cells) to TGFß1 that mimics phenotypic EMT (M-cells) and MET. We aimed at understanding whether phenotypic MET is accompanied by molecular and functional reversion back to epithelia by using RNA sequencing, immunofluorescence (IF), proliferation, wound healing, focus formation and mamosphere formation assays as well as cell xenografts in nude mice. Phenotypic reverted epithelial cells (RE-cells) obtained after MET induction presented epithelial morphologies and proliferation rates resembling E cells. However, the RE transcriptomic profile and IF staining of epithelial and mesenchymal markers revealed a uniquely heterogeneous mixture of cell subpopulations with a high self-renewal ability. RE cell heterogeneity was stably maintained for long periods after TGFß1 removal both in vitro and in large tumours derived from the nude mice. Overall, we show that phenotypic reverted epithelial cells (RE cells) do not return to the molecular and functional epithelial state and present mesenchymal features related to aggressiveness and cellular heterogeneity that favour tumour growth in vivo. This work strengthens epithelial cell reprogramming and cellular heterogeneity fostered by inflammatory cues as a tumour growth-promoting factor in vivo.

5.
Cells ; 11(6)2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35326385

RESUMO

Breast cancer is the most common malignancy affecting women worldwide. Importantly, there have been significant improvements in prevention, early diagnosis, and treatment options, which resulted in a significant decrease in breast cancer mortality rates. Nevertheless, the high rates of incidence combined with therapy resistance result in cancer relapse and metastasis, which still contributes to unacceptably high mortality of breast cancer patients. In this context, a small subpopulation of highly tumourigenic cancer cells within the tumour bulk, commonly designated as breast cancer stem cells (BCSCs), have been suggested as key elements in therapy resistance, which are responsible for breast cancer relapses and distant metastasis. Thus, improvements in BCSC-targeting therapies are crucial to tackling the metastatic progression and might allow therapy resistance to be overcome. However, the design of effective and specific BCSC-targeting therapies has been challenging since there is a lack of specific biomarkers for BCSCs, and the most common clinical approaches are designed for commonly altered BCSCs signalling pathways. Therefore, the search for a new class of BCSC biomarkers, such as the expression of membrane proteins with cancer stem cell potential, is an area of clinical relevance, once membrane proteins are accessible on the cell surface and easily recognized by specific antibodies. Here, we discuss the significance of BCSC membrane biomarkers as potential prognostic and therapeutic targets, reviewing the CSC-targeting therapies under clinical trials for breast cancer.


Assuntos
Neoplasias da Mama , Biomarcadores/metabolismo , Neoplasias da Mama/patologia , Feminino , Humanos , Proteínas de Membrana/metabolismo , Recidiva Local de Neoplasia/metabolismo , Células-Tronco Neoplásicas/patologia
6.
Mater Today Bio ; 13: 100219, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35243294

RESUMO

Organ-on-a-chip models have emerged as a powerful tool to model cancer metastasis and to decipher specific crosstalk between cancer cells and relevant regulators of this particular niche. Recently, the sympathetic nervous system (SNS) was proposed as an important modulator of breast cancer bone metastasis. However, epidemiological studies concerning the benefits of the SNS targeting drugs on breast cancer survival and recurrence remain controversial. Thus, the role of SNS signaling over bone metastatic cancer cellular processes still requires further clarification. Herein, we present a novel humanized organ-on-a-chip model recapitulating neuro-breast cancer crosstalk in a bone metastatic context. We developed and validated an innovative three-dimensional printing based multi-compartment microfluidic platform, allowing both selective and dynamic multicellular paracrine signaling between sympathetic neurons, bone tropic breast cancer cells and osteoclasts. The selective multicellular crosstalk in combination with biochemical, microscopic and proteomic profiling show that synergistic paracrine signaling from sympathetic neurons and osteoclasts increase breast cancer aggressiveness demonstrated by augmented levels of pro-inflammatory cytokines (e.g. interleukin-6 and macrophage inflammatory protein 1α). Overall, this work introduced a novel and versatile platform that could potentially be used to unravel new mechanisms involved in intracellular communication at the bone metastatic niche.

7.
Acta Med Port ; 35(2): 135-143, 2022 Feb 01.
Artigo em Português | MEDLINE | ID: mdl-35225777

RESUMO

Repairing damage and errors that occur in the DNA molecule is essential to maintain the integrity of the genome and cell viability. Deficits in DNA repair mechanisms lead to an increased risk of genetic instability and contribute to neoplastic transformation. Poly (ADP-ribose) polymerases (PARP) are a group of enzymes that play a key role in signalling and repairing DNA errors. The inhibition of its activity is a therapeutic strategy that takes advantage of the mechanism of synthetic lethality and that can be used in the treatment of tumours with specific defects in DNA repair pathways, namely in tumours with mutations in the tumour suppressor genes BRCA1 and BRCA2. There are several PARP inhibitors (iPARP), already approved by the USA Food and Drug Administration and the European Medicines Agency used in the treatment of breast, ovarian, pancreatic and prostate cancer. However, as with other target therapies, despite being well tolerated and widely used in the clinical practice, iPARP resistance is common and can be developed through various molecular mechanisms. In this article, we intend to make an updated review on iPARP and its main role in tumour cells, highlighting the several resistance mechanisms that have been recently revealed, as well as the current clinical applications and toxicity associated with this target therapy.


A reparação dos danos que ocorrem na molécula de ADN é fundamental para manter a integridade do genoma e a viabilidade celular. Défices nos mecanismos de reparação desta molécula cursam com um aumento do risco para instabilidade genética e contribuem para a transformação neoplásica. As poly (ADP-ribose) polymerases (PARP) são um grupo de enzimas que apresentam um papel chave na sinalização e reparação dos erros no ADN. A inibição da sua atividade é uma estratégia terapêutica que tira partido do mecanismo de letalidade sintética e que pode ser usada no tratamento de tumores com defeitos específicos nas vias de reparação de ADN, nomeadamente em tumores com mutações nos genes supressores tumorais BRCA1 e BRCA2. Existem vários inibidores das PARP (iPARP) já aprovados pela Food and Drug Administration dos Estados Unidos da América e pela Agência Europeia do Medicamento e utilizados no tratamento do cancro da mama, ovário, pâncreas e próstata. No entanto, tal como acontece com outras terapias alvo, a resistência aos iPARP é comum apesar de bem tolerados e amplamente utilizados na prática clínica, e pode desenvolver-se através de vários mecanismos moleculares. Neste artigo, pretendemos realizar uma revisão atualizada sobre os iPARP e o seu principal modo de ação em células tumorais, dando a conhecer os vários mecanismos de resistência que têm sido recentemente revelados, assim como as atuais aplicações clínicas e a toxicidade associada a esta terapia alvo.


Assuntos
Neoplasias Ovarianas , Inibidores de Poli(ADP-Ribose) Polimerases , Reparo do DNA , Genes BRCA2 , Humanos , Masculino , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Poli(ADP-Ribose) Polimerases/uso terapêutico
8.
J Neurooncol ; 156(3): 453-464, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35066764

RESUMO

PURPOSE: Glioblastoma is the most common primary malignant brain tumor in the adult, whose grim prognosis largely relates to the absence of effective treatment targets. Given its success in other cancers, immunotherapy has been trialed in glioblastoma and failed to demonstrate the expected benefit. Importantly, these disappointing results highlight the importance of understanding the unique and transforming biology of glioblastoma and its microenvironment. Our goal was to evaluate and characterize the expression of PD-L1 through immunohistochemistry in a large glioblastoma cohort. We further studied PD-L1 expression-associated prognosis and its correlation to systemic and neuropathological parameters. METHODS: A series of 352 glioblastoma specimens (313 initial resection, 39 matched recurrences) was collected, with a detailed characterization of tumor neuropathological characteristics, including the presence, density and location of tumor infiltrating lymphocytes (TIL). Two hematological markers, absolute lymphocyte count and neutrophil-lymphocyte ratio (NLR), were used to analyze and correlate with systemic inflammation and immunosuppression. Immunohistochemistry was performed to evaluate PD-L1 expression. RESULTS: Membranous PD-L1 expression was identified in 31% (98/313) of newly diagnosed and 46% (18/39) of matched recurrent tumors. TIL were found in 26% (82/313) of primary tumors and both density and location were found to be significantly associated with PD-L1 expression (p < 0.001). Interestingly, PD-L1 expressing tumors had more frequently areas with sarcomatous differentiation (p < 0.001) and were significantly associated with lower lymphocyte count (p = 0.018) and higher NLR ratio (p = 0.004) upon diagnosis. Importantly, PD-L1 expression was an independent poor prognostic marker in our cohort. CONCLUSION: Taken together, our data points to a putative role for PD-L1 expression in glioblastoma biology, which correlates to poor patient overall survival, as well as with a general systemic inflammatory status and immunosuppression.


Assuntos
Antígeno B7-H1 , Glioblastoma , Adulto , Antígeno B7-H1/metabolismo , Glioblastoma/imunologia , Glioblastoma/patologia , Humanos , Prognóstico
9.
Mol Oncol ; 16(14): 2611-2631, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34919784

RESUMO

Glioblastoma (GBM) is the most common and malignant primary brain tumor in adults. The prognosis of patients is very poor, with a median overall survival of ~ 15 months after diagnosis. Cadherin-3 (also known as P-cadherin), a cell-cell adhesion molecule encoded by the CDH3 gene, is deregulated in several cancer types, but its relevance in GBM is unknown. In this study, we investigated the functional roles, the associated molecular signatures, and the prognostic value of CDH3/P-cadherin in this highly malignant brain tumor. CDH3/P-cadherin mRNA and protein levels were evaluated in human glioma samples. Knockdown and overexpression models of P-cadherin in GBM were used to evaluate its functional role in vitro and in vivo. CDH3-associated gene signatures were identified by enrichment analyses and correlations. The impact of CDH3 in the survival of GBM patients was assessed in independent cohorts using both univariable and multivariable models. We found that P-cadherin protein is expressed in a subset of gliomas, with an increased percentage of positive samples in grade IV tumors. Concordantly, CDH3 mRNA levels in glioma samples from The Cancer Genome Atlas (TCGA) database are increased in high-grade gliomas. P-cadherin displays oncogenic functions in multiple knockdown and overexpression GBM cell models by affecting cell viability, cell cycle, cell invasion, migration, and neurosphere formation capacity. Genes that were positively correlated with CDH3 are enriched for oncogenic pathways commonly activated in GBM. In vivo, GBM cells expressing high levels of P-cadherin generate larger subcutaneous tumors and cause shorter survival of mice in an orthotopic intracranial model. Concomitantly, high CDH3 expression is predictive of shorter overall survival of GBM patients in independent cohorts. Together, our results show that CDH3/P-cadherin expression is associated with aggressiveness features of GBM and poor patient prognosis, suggesting that it may be a novel therapeutic target for this deadly brain tumor.


Assuntos
Neoplasias Encefálicas , Caderinas , Glioblastoma , Glioma , Adulto , Animais , Biomarcadores , Neoplasias Encefálicas/genética , Caderinas/genética , Carcinogênese/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioma/genética , Humanos , Camundongos , Prognóstico , RNA Mensageiro/genética
10.
Biomedicines ; 9(10)2021 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-34680444

RESUMO

Cadherins are calcium-binding proteins with a pivotal role in cell adhesion and tissue homeostasis. The cadherin-dependent mechanisms of cell adhesion and migration are exploited by cancer cells, contributing to tumor invasiveness and dissemination. In particular, cadherin switch is a hallmark of epithelial to mesenchymal transition, a complex development process vastly described in the progression of most epithelial cancers. This is characterized by drastic changes in cell polarity, adhesion, and motility, which lead from an E-cadherin positive differentiated epithelial state into a dedifferentiated mesenchymal-like state, prone to metastization and defined by N-cadherin expression. Although vastly explored in epithelial cancers, how these mechanisms contribute to the pathogenesis of other non-epithelial tumor types is poorly understood. Herein, the current knowledge on cadherin expression in normal development in parallel to tumor pathogenesis is reviewed, focusing on epithelial to mesenchymal transition. Emphasis is taken in the unascertained cadherin expression in CNS tumors, particularly in gliomas, where the potential contribution of an epithelial-to-mesenchymal-like process to glioma genesis and how this may be associated with changes in cadherin expression is discussed.

11.
Bone Res ; 9(1): 9, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33547275

RESUMO

The vast majority of patients with advanced breast cancer present skeletal complications that severely compromise their quality of life. Breast cancer cells are characterized by a strong tropism to the bone niche. After engraftment and colonization of bone, breast cancer cells interact with native bone cells to hinder the normal bone remodeling process and establish an osteolytic "metastatic vicious cycle". The sympathetic nervous system has emerged in recent years as an important modulator of breast cancer progression and metastasis, potentiating and accelerating the onset of the vicious cycle and leading to extensive bone degradation. Furthermore, sympathetic neurotransmitters and their cognate receptors have been shown to promote several hallmarks of breast cancer, such as proliferation, angiogenesis, immune escape, and invasion of the extracellular matrix. In this review, we assembled the current knowledge concerning the complex interactions that take place in the tumor microenvironment, with a special emphasis on sympathetic modulation of breast cancer cells and stromal cells. Notably, the differential action of epinephrine and norepinephrine, through either α- or ß-adrenergic receptors, on breast cancer progression prompts careful consideration when designing new therapeutic options. In addition, the contribution of sympathetic innervation to the formation of bone metastatic foci is highlighted. In particular, we address the remarkable ability of adrenergic signaling to condition the native bone remodeling process and modulate the bone vasculature, driving breast cancer cell engraftment in the bone niche. Finally, clinical perspectives and developments on the use of ß-adrenergic receptor inhibitors for breast cancer management and treatment are discussed.

12.
Cells ; 9(11)2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-33182375

RESUMO

Brain metastases remain an unmet clinical need in breast oncology, being frequently found in HER2-overexpressing and triple-negative carcinomas. These tumors were reported to be highly cancer stem-like cell-enriched, suggesting that brain metastases probably arise by the seeding of cancer cells with stem features. Accordingly, we found that brain-tropic breast cancer cells show increased stem cell activity and tumorigenic capacity in the chick embryo choriallantoic membrane when compared to the parental cell line. These observations were supported by a significant increase in their stem cell frequency and by the enrichment for the breast cancer stem cell (BCSC) phenotype CD44+CD24-/low. Based on this data, the expression of BCSC markers (CD44, CD49f, P-cadherin, EpCAM, and ALDH1) was determined and found to be significantly enriched in breast cancer brain metastases when compared to primary tumors. Therefore, a brain (BR)-BCSC signature was defined (3-5 BCSC markers), which showed to be associated with decreased brain metastases-free and overall survival. Interestingly, this signature significantly predicted a worse prognosis in lymph node-positive patients, acting as an independent prognostic factor. Thus, an enrichment of a BCSC signature was found in brain metastases, which can be used as a new prognostic factor in clinically challenging breast cancer patients.


Assuntos
Neoplasias Encefálicas/patologia , Neoplasias da Mama/patologia , Linfonodos/patologia , Células-Tronco Neoplásicas/patologia , Animais , Biomarcadores Tumorais/metabolismo , Carcinogênese/patologia , Linhagem Celular Tumoral , Embrião de Galinha , Membrana Corioalantoide/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Camundongos , Análise Multivariada , Prognóstico , Modelos de Riscos Proporcionais
13.
Biochim Biophys Acta Mol Basis Dis ; 1866(12): 165964, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920119

RESUMO

Successful metastatic spreading relies on cancer cells with stem-like properties, glycolytic metabolism and increased antioxidant protection, allowing them to escape anoikis and to survive in circulation. The expression of P-cadherin, a poor prognostic factor in breast cancer, is associated with hypoxic, glycolytic and acidosis biomarkers. In agreement, P-cadherin-enriched breast cancer cell populations presents a glycolytic and an acid-resistance phenotype. Our aim was to evaluate whether P-cadherin expression controls the glycolytic and oxidative phosphorylation fluxes of matrix-detached breast cancer cells, acting as an antioxidant and enhancing their survival in anchorage-independent conditions. By using matrix-detached breast cancer cells, we concluded that P-cadherin increases glucose-6-phosphate dehydrogenase expression, up-regulating the carbon flux through the pentose phosphate pathway, while inhibiting pyruvate oxidation to acetyl-coA via pyruvate dehydrogenase kinase-4 (PDK-4) activation. Accordingly, P-cadherin expression conferred increased sensitivity to dichloroacetate (DCA), a PDK inhibitor. P-cadherin expression also regulates oxidative stress in matrix-detached breast cancer cells, through the control of antioxidant systems, such as catalase and superoxide dismutases (SOD)1 and 2, providing these cells with an increased resistance to doxorubicin-induced anoikis. Importantly, this association was validated in primary invasive breast carcinomas, where an enrichment of SOD2 was found in P-cadherin-overexpressing breast carcinomas. In conclusion, we propose that P-cadherin up-regulates carbon flux through the pentose phosphate pathway and decreases oxidative stress in matrix-detached breast cancer cells. These metabolic remodeling and antioxidant roles of P-cadherin can promote the survival of breast cancer cells in circulation and in metastatic sites, being a possible player in breast cancer therapeutic resistance to pro-oxidant-based interventions.


Assuntos
Anoikis , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Caderinas/metabolismo , Matriz Extracelular/metabolismo , Estresse Oxidativo , Feminino , Humanos , Via de Pentose Fosfato , Espécies Reativas de Oxigênio/metabolismo , Células Tumorais Cultivadas
14.
Int J Mol Sci ; 22(1)2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-33396951

RESUMO

The high plasticity of cancer stem-like cells (CSCs) allows them to differentiate and proliferate, specifically when xenotransplanted subcutaneously into immunocompromised mice. CSCs are highly tumorigenic, even when inoculated in small numbers. Thus, in vivo limiting dilution assays (LDA) in mice are the current gold standard method to evaluate CSC enrichment and activity. The chick embryo chorioallantoic membrane (CAM) is a low cost, naturally immune-incompetent and reproducible model widely used to evaluate the spontaneous growth of human tumor cells. Here, we established a CAM-LDA assay able to rapidly reproduce tumor specificities-in particular, the ability of the small population of CSCs to form tumors. We used a panel of organotropic metastatic breast cancer cells, which show an enrichment in a stem cell gene signature, enhanced CD44+/CD24-/low cell surface expression and increased mammosphere-forming efficiency (MFE). The size of CAM-xenografted tumors correlate with the number of inoculated cancer cells, following mice xenograft growth pattern. CAM and mice tumors are histologically comparable, displaying both breast CSC markers CD44 and CD49f. Therefore, we propose a new tool for studying CSC prevalence and function-the chick CAM-LDA-a model with easy handling, accessibility, rapid growth and the absence of ethical and regulatory constraints.


Assuntos
Neoplasias da Mama/patologia , Membrana Corioalantoide , Células-Tronco Neoplásicas/patologia , Animais , Apoptose , Neoplasias da Mama/metabolismo , Movimento Celular , Proliferação de Células , Embrião de Galinha , Feminino , Humanos , Receptores de Hialuronatos/metabolismo , Camundongos , Camundongos Nus , Células-Tronco Neoplásicas/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Cell Commun Signal ; 17(1): 155, 2019 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-31767037

RESUMO

BACKGROUND: E-cadherin has been awarded a key role in the aetiology of both sporadic and hereditary forms of gastric cancer. In this study, we aimed to identify molecular interactors that influence the expression and function of E-cadherin associated to cancer. METHODS: A data mining approach was used to predict stomach-specific candidate genes, uncovering S100P as a key candidate. The role of S100P was evaluated through in vitro functional assays and its expression was studied in a gastric cancer tissue microarray (TMA). RESULTS: S100P was found to contribute to a cancer pathway dependent on the context of E-cadherin function. In particular, we demonstrated that S100P acts as an E-cadherin positive regulator in a wild-type E-cadherin context, and its inhibition results in decreased E-cadherin expression and function. In contrast, S100P is likely to be a pro-survival factor in gastric cancer cells with loss of functional E-cadherin, contributing to an oncogenic molecular program. Moreover, expression analysis in a gastric cancer TMA revealed that S100P expression impacts negatively among patients bearing Ecad- tumours, despite not being significantly associated with overall survival on its own. CONCLUSIONS: We propose that S100P has a dual role in gastric cancer, acting as an oncogenic factor in the context of E-cadherin loss and as a tumour suppressor in a functional E-cadherin setting. The discovery of antagonist effects of S100P in different E-cadherin contexts will aid in the stratification of gastric cancer patients who may benefit from S100P-targeted therapies.


Assuntos
Caderinas/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Gástricas/metabolismo , Caderinas/genética , Proteínas de Ligação ao Cálcio/genética , Humanos , Proteínas de Neoplasias/genética , Transdução de Sinais/genética , Neoplasias Gástricas/patologia , Células Tumorais Cultivadas
16.
J Biotechnol ; 300: 70-77, 2019 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-31150679

RESUMO

Adeno-associated viral vectors (AAV) for gene therapy applications are gaining momentum, with more therapies moving into later stages of clinical development and towards market approval, namely for cancer therapy. The development of cytotoxic vectors is often hampered by side effects arising when non-target cells are infected, and their production can be hindered by toxic effects of the transgene on the producing cell lines. In this study, we evaluated the potential of rAAV-mediated delivery of short hairpin RNAs (shRNA) to target basal-like breast cancer genetic vulnerabilities. Our results show that by optimizing the stoichiometry of the plasmids upon transfection and time of harvest, it is possible to increase the viral titers and quality. All rAAV-shRNA vectors obtained efficiently transduced the BLBC cell lines MDA-MB-468 and HCC1954. In MDA-MB-468, transduction with rAAV-shRNA vector targeting PSMA2 was associated with significant decrease in cell viability and apoptosis induction. Importantly, rAAV2-PSMA2 also slowed tumor growth in a BLBC mouse xenograft model, thus potentially representing a therapeutic strategy against this type of cancer.


Assuntos
Neoplasias da Mama/genética , Dependovirus/genética , Neoplasia de Células Basais/genética , RNA Interferente Pequeno/genética , Animais , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Técnicas de Silenciamento de Genes , Técnicas de Transferência de Genes/normas , Terapia Genética , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Células HEK293 , Humanos , Camundongos , Camundongos Nus , Neoplasia de Células Basais/patologia , Neoplasia de Células Basais/terapia , Plasmídeos , Complexo de Endopeptidases do Proteassoma/genética , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/farmacologia , Fatores de Tempo , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Adv Exp Med Biol ; 1139: 83-103, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31134496

RESUMO

In the last 20 years, the conventional view of breast cancer as a homogeneous collection of highly proliferating malignant cells was totally replaced by a model of increased complexity, which points out that breast carcinomas are tissues composed of multiple populations of transformed cells. A large diversity of host cells and structural components of the extracellular matrix constitute the mammary tumour microenvironment, which supports its growth and progression, where individual cancer cells evolve with cumulative phenotypic and genetic heterogeneity. Moreover, contributing to this heterogeneity, it has been demonstrated that breast cancers can exhibit a hierarchical organization composed of tumour cells displaying divergent lineage biomarkers and where, at the apex of this hierarchy, some neoplastic cells are able to self-renew and to aberrantly differentiate. Breast cancer stem cells (BCSCs), as they were entitled, not only drive tumourigenesis, but also mediate metastasis and contribute to therapy resistance.Recently, adding more complexity to the system, it has been demonstrated that BCSCs maintain high levels of plasticity, being able to change between mesenchymal-like and epithelial-like states in a process regulated by the tumour microenvironment. These stem cell state transitions play a fundamental role in the process of tumour metastasis, as well as in the resistance to putative therapeutic strategies to target these cells. In this chapter, it will be mainly discussed the emerging knowledge regarding the contribution of BCSCs to tumour heterogeneity, their plasticity, and the role that this plasticity can play in the establishment of distant metastasis. A major focus will also be given to potential clinical implications of these discoveries in breast cancer recurrence and to possible BCSC targeted therapeutics by the use of specific biomarkers.


Assuntos
Neoplasias da Mama/patologia , Células-Tronco Neoplásicas/citologia , Microambiente Tumoral , Biomarcadores Tumorais , Transição Epitelial-Mesenquimal , Feminino , Humanos , Recidiva Local de Neoplasia
18.
Int J Mol Sci ; 20(8)2019 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-31010154

RESUMO

Cancer cells preferentially use aerobic glycolysis over mitochondria oxidative phosphorylation for energy production, and this metabolic reprogramming is currently recognized as a hallmark of cancer. Oncogenic signaling frequently converges with this metabolic shift, increasing cancer cells' ability to produce building blocks and energy, as well as to maintain redox homeostasis. Alterations in cell-cell and cell-extracellular matrix (ECM) adhesion promote cancer cell invasion, intravasation, anchorage-independent survival in circulation, and extravasation, as well as homing in a distant organ. Importantly, during this multi-step metastatic process, cells need to induce metabolic rewiring, in order to produce the energy needed, as well as to impair oxidative stress. Although the individual implications of adhesion molecules and metabolic reprogramming in cancer have been widely explored over the years, the crosstalk between cell adhesion molecular machinery and metabolic pathways is far from being clearly understood, in both normal and cancer contexts. This review summarizes our understanding about the influence of cell-cell and cell-matrix adhesion in the metabolic behavior of cancer cells, with a special focus concerning the role of classical cadherins, such as Epithelial (E)-cadherin and Placental (P)-cadherin.


Assuntos
Neoplasias/metabolismo , Neoplasias/patologia , Animais , Fenômenos Biomecânicos , Adesão Celular , Junções Célula-Matriz/metabolismo , Progressão da Doença , Transição Epitelial-Mesenquimal , Humanos
19.
PLoS Comput Biol ; 15(3): e1006832, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30856170

RESUMO

Centrosome amplification (CA) is a common feature of human tumours and a promising target for cancer therapy. However, CA's pan-cancer prevalence, molecular role in tumourigenesis and therapeutic value in the clinical setting are still largely unexplored. Here, we used a transcriptomic signature (CA20) to characterise the landscape of CA-associated gene expression in 9,721 tumours from The Cancer Genome Atlas (TCGA). CA20 is upregulated in cancer and associated with distinct clinical and molecular features of breast cancer, consistently with our experimental CA quantification in patient samples. Moreover, we show that CA20 upregulation is positively associated with genomic instability, alteration of specific chromosomal arms and C>T mutations, and we propose novel molecular players associated with CA in cancer. Finally, high CA20 is associated with poor prognosis and, by integrating drug sensitivity with drug perturbation profiles in cell lines, we identify candidate compounds for selectively targeting cancer cells exhibiting transcriptomic evidence for CA.


Assuntos
Neoplasias da Mama/genética , Centrossomo , Perfilação da Expressão Gênica , Atlas como Assunto , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Aberrações Cromossômicas , Feminino , Instabilidade Genômica , Humanos , Mutação , Prognóstico , Transcriptoma , Resultado do Tratamento , Regulação para Cima
20.
J Med Genet ; 56(4): 199-208, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30661051

RESUMO

CDH1 encodes E-cadherin, a key protein in adherens junctions. Given that E-cadherin is involved in major cellular processes such as embryogenesis and maintenance of tissue architecture, it is no surprise that deleterious effects arise from its loss of function. E-cadherin is recognised as a tumour suppressor gene, and it is well established that CDH1 genetic alterations cause diffuse gastric cancer and lobular breast cancer-the foremost manifestations of the hereditary diffuse gastric cancer syndrome. However, in the last decade, evidence has emerged demonstrating that CDH1 mutations can be associated with lobular breast cancer and/or several congenital abnormalities, without any personal or family history of diffuse gastric cancer. To date, no genotype-phenotype correlations have been observed. Remarkably, there are reports of mutations affecting the same nucleotide but inducing distinct clinical outcomes. In this review, we bring together a comprehensive analysis of CDH1-associated disorders and germline alterations found in each trait, providing important insights into the biological mechanisms underlying E-cadherin's pleiotropic effects. Ultimately, this knowledge will impact genetic counselling and will be relevant to the assessment of risk of cancer development or congenital malformations in CDH1 mutation carriers.


Assuntos
Antígenos CD/genética , Caderinas/genética , Diferenciação Celular/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Alelos , Neoplasias da Mama/genética , Transformação Celular Neoplásica , Fenda Labial/genética , Fissura Palatina/genética , Ectrópio/genética , Feminino , Estudos de Associação Genética/métodos , Genótipo , Humanos , Masculino , Neoplasias Gástricas/genética , Anormalidades Dentárias/genética
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