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1.
Cancers (Basel) ; 16(13)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39001506

RESUMO

The field of healthcare is increasingly adopting a humanistic perspective in the physician-patient relationship. One of the more salient aspects being studied is the communication between the two. This study serves a dual purpose. Our initial aim was to study how a cancer diagnosis is disclosed to patients by different physicians (GPs/other specialists/oncologists). Secondly, we set out to study how the way in which oncologists normally communicate with their patients impacts variables such as a patient's anxiety, depression, coping mechanisms, and perception of both their health and their quality of life. A total of 177 patients answered a battery of questionnaires on sociodemographic and disease data: the SPIKES protocol, the EORTCQLQ-COMU26, and the ADAF screening questionnaire. The analyses recorded medium or high scores for some of the steps in the SPIKES protocol when delivering the diagnosis, and significant differences were observed for some of them among different physicians. The level of a cancer patient's satisfaction with the communication by oncologists was related to their levels of anxiety, depression, vulnerability, and perception of their health and quality of life. Better communication strategies are called for among all healthcare professionals to facilitate the task of breaking bad news to their patients.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38806657

RESUMO

Despite extensive research and improvements in understanding colorectal cancer (CRC), its metastatic form continues to pose a substantial challenge, primarily owing to limited therapeutic options and a poor prognosis. This Review addresses the emerging focus on metastatic CRC (mCRC), which has historically been under-studied compared with primary CRC despite its lethality. We delve into two crucial aspects: the molecular and cellular determinants facilitating CRC metastasis and the principles guiding the evolution of metastatic disease. Initially, we examine the genetic alterations integral to CRC metastasis, connecting them to clinically marked characteristics of advanced CRC. Subsequently, we scrutinize the role of cellular heterogeneity and plasticity in metastatic spread and therapy resistance. Finally, we explore how the tumour microenvironment influences metastatic disease, emphasizing the effect of stromal gene programmes and the immune context. The ongoing research in these fields holds immense importance, as its future implications are projected to revolutionize the treatment of patients with mCRC, hopefully offering a promising outlook for their survival.

3.
Nature ; 611(7936): 603-613, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36352230

RESUMO

Around 30-40% of patients with colorectal cancer (CRC) undergoing curative resection of the primary tumour will develop metastases in the subsequent years1. Therapies to prevent disease relapse remain an unmet medical need. Here we uncover the identity and features of the residual tumour cells responsible for CRC relapse. An analysis of single-cell transcriptomes of samples from patients with CRC revealed that the majority of genes associated with a poor prognosis are expressed by a unique tumour cell population that we named high-relapse cells (HRCs). We established a human-like mouse model of microsatellite-stable CRC that undergoes metastatic relapse after surgical resection of the primary tumour. Residual HRCs occult in mouse livers after primary CRC surgery gave rise to multiple cell types over time, including LGR5+ stem-like tumour cells2-4, and caused overt metastatic disease. Using Emp1 (encoding epithelial membrane protein 1) as a marker gene for HRCs, we tracked and selectively eliminated this cell population. Genetic ablation of EMP1high cells prevented metastatic recurrence and mice remained disease-free after surgery. We also found that HRC-rich micrometastases were infiltrated with T cells, yet became progressively immune-excluded during outgrowth. Treatment with neoadjuvant immunotherapy eliminated residual metastatic cells and prevented mice from relapsing after surgery. Together, our findings reveal the cell-state dynamics of residual disease in CRC and anticipate that therapies targeting HRCs may help to avoid metastatic relapse.


Assuntos
Neoplasias Colorretais , Metástase Neoplásica , Proteínas de Neoplasias , Recidiva Local de Neoplasia , Neoplasia Residual , Receptores de Superfície Celular , Animais , Humanos , Camundongos , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Progressão da Doença , Proteínas de Neoplasias/deficiência , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/prevenção & controle , Recidiva Local de Neoplasia/terapia , Neoplasia Residual/genética , Neoplasia Residual/patologia , Receptores de Superfície Celular/deficiência , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Metástase Neoplásica/genética , Metástase Neoplásica/patologia , Metástase Neoplásica/prevenção & controle , Metástase Neoplásica/terapia , Modelos Animais de Doenças , Linfócitos T/citologia , Linfócitos T/imunologia , Linfócitos do Interstício Tumoral/citologia , Linfócitos do Interstício Tumoral/imunologia , Terapia Neoadjuvante , Imunoterapia
4.
Nat Cancer ; 3(9): 1052-1070, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35773527

RESUMO

Colorectal cancer (CRC) patient-derived organoids predict responses to chemotherapy. Here we used them to investigate relapse after treatment. Patient-derived organoids expand from highly proliferative LGR5+ tumor cells; however, we discovered that lack of optimal growth conditions specifies a latent LGR5+ cell state. This cell population expressed the gene MEX3A, is chemoresistant and regenerated the organoid culture after treatment. In CRC mouse models, Mex3a+ cells contributed marginally to metastatic outgrowth; however, after chemotherapy, Mex3a+ cells produced large cell clones that regenerated the disease. Lineage-tracing analysis showed that persister Mex3a+ cells downregulate the WNT/stem cell gene program immediately after chemotherapy and adopt a transient state reminiscent to that of YAP+ fetal intestinal progenitors. In contrast, Mex3a-deficient cells differentiated toward a goblet cell-like phenotype and were unable to resist chemotherapy. Our findings reveal that adaptation of cancer stem cells to suboptimal niche environments protects them from chemotherapy and identify a candidate cell of origin of relapse after treatment in CRC.


Assuntos
Neoplasias Colorretais , Organoides , Animais , Diferenciação Celular , Neoplasias Colorretais/tratamento farmacológico , Camundongos , Células-Tronco Neoplásicas , Recidiva
5.
Nat Cancer ; 3(4): 418-436, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35469014

RESUMO

Patient-derived organoids (PDOs) recapitulate tumor architecture, contain cancer stem cells and have predictive value supporting personalized medicine. Here we describe a large-scale functional screen of dual-targeting bispecific antibodies (bAbs) on a heterogeneous colorectal cancer PDO biobank and paired healthy colonic mucosa samples. More than 500 therapeutic bAbs generated against Wingless-related integration site (WNT) and receptor tyrosine kinase (RTK) targets were functionally evaluated by high-content imaging to capture the complexity of PDO responses. Our drug discovery strategy resulted in the generation of MCLA-158, a bAb that specifically triggers epidermal growth factor receptor degradation in leucine-rich repeat-containing G-protein-coupled receptor 5-positive (LGR5+) cancer stem cells but shows minimal toxicity toward healthy LGR5+ colon stem cells. MCLA-158 exhibits therapeutic properties such as growth inhibition of KRAS-mutant colorectal cancers, blockade of metastasis initiation and suppression of tumor outgrowth in preclinical models for several epithelial cancer types.


Assuntos
Anticorpos Biespecíficos , Neoplasias Epiteliais e Glandulares , Anticorpos Biespecíficos/farmacologia , Receptores ErbB/metabolismo , Humanos , Imidazóis , Neoplasias Epiteliais e Glandulares/metabolismo , Células-Tronco Neoplásicas/metabolismo , Organoides , Pirazinas , Receptores Acoplados a Proteínas G/metabolismo
6.
Nat Rev Cancer ; 22(1): 25-44, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34671117

RESUMO

Transforming growth factor-ß (TGFß) signalling controls multiple cell fate decisions during development and tissue homeostasis; hence, dysregulation of this pathway can drive several diseases, including cancer. Here we discuss the influence that TGFß exerts on the composition and behaviour of different cell populations present in the tumour immune microenvironment, and the context-dependent functions of this cytokine in suppressing or promoting cancer. During homeostasis, TGFß controls inflammatory responses triggered by exposure to the outside milieu in barrier tissues. Lack of TGFß exacerbates inflammation, leading to tissue damage and cellular transformation. In contrast, as tumours progress, they leverage TGFß to drive an unrestrained wound-healing programme in cancer-associated fibroblasts, as well as to suppress the adaptive immune system and the innate immune system. In consonance with this key role in reprogramming the tumour microenvironment, emerging data demonstrate that TGFß-inhibitory therapies can restore cancer immunity. Indeed, this approach can synergize with other immunotherapies - including immune checkpoint blockade - to unleash robust antitumour immune responses in preclinical cancer models. Despite initial challenges in clinical translation, these findings have sparked the development of multiple therapeutic strategies that inhibit the TGFß pathway, many of which are currently in clinical evaluation.


Assuntos
Neoplasias , Fator de Crescimento Transformador beta , Humanos , Evasão da Resposta Imune , Imunoterapia , Neoplasias/patologia , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/uso terapêutico , Microambiente Tumoral
7.
Cell Stem Cell ; 26(6): 845-861.e12, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32396863

RESUMO

Colorectal cancers (CRCs) are composed of an amalgam of cells with distinct genotypes and phenotypes. Here, we reveal a previously unappreciated heterogeneity in the biosynthetic capacities of CRC cells. We discover that the majority of ribosomal DNA transcription and protein synthesis in CRCs occurs in a limited subset of tumor cells that localize in defined niches. The rest of the tumor cells undergo an irreversible loss of their biosynthetic capacities as a consequence of differentiation. Cancer cells within the biosynthetic domains are characterized by elevated levels of the RNA polymerase I subunit A (POLR1A). Genetic ablation of POLR1A-high cell population imposes an irreversible growth arrest on CRCs. We show that elevated biosynthesis defines stemness in both LGR5+ and LGR5- tumor cells. Therefore, a common architecture in CRCs is a simple cell hierarchy based on the differential capacity to transcribe ribosomal DNA and synthesize proteins.


Assuntos
Neoplasias Colorretais , Células-Tronco Neoplásicas , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , DNA Ribossômico , Humanos , Receptores Acoplados a Proteínas G
8.
J Cell Physiol ; 233(2): 849-855, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28063221

RESUMO

Currently, a liver biopsy remains the only reliable way to precisely diagnose non-alcoholic fatty liver disease (NAFLD) and establish the severity of liver injury, presence of fibrosis, and architecture remodeling. However, the cost and the intrinsic invasive procedure of a liver biopsy rules it out as a gold standard diagnostic test, and the imaging test are not the best choice due to the price, and currently is being refined. The lack of a biomarker of NAFLD pushes to develop this new line of research. The aim of the present systematic review is to clarify and update all the NAFLD biomarkers described in the literature until recently. We highlight α-ketoglutarate and CK18-F as currently the best potential biomarker of NAFLD. However, due to methodological differences, we propose the implementation of international, multicenter, multiethnic studies with larger population size, and biopsy proven NAFLD diagnosis to analyze and compare α-ketoglutarate and CK18-F as potential biomarkers of the silent evolution of NAFLD.


Assuntos
Queratina-18/sangue , Ácidos Cetoglutáricos/sangue , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/sangue , Animais , Biomarcadores/sangue , Biópsia , Humanos , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Valor Preditivo dos Testes , Prognóstico , Reprodutibilidade dos Testes
9.
EMBO Mol Med ; 9(7): 869-879, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28468934

RESUMO

The analysis of stem cell hierarchies in human cancers has been hampered by the impossibility of identifying or tracking tumor cell populations in an intact environment. To overcome this limitation, we devised a strategy based on editing the genomes of patient-derived tumor organoids using CRISPR/Cas9 technology to integrate reporter cassettes at desired marker genes. As proof of concept, we engineered human colorectal cancer (CRC) organoids that carry EGFP and lineage-tracing cassettes knocked in the LGR5 locus. Analysis of LGR5-EGFP+ cells isolated from organoid-derived xenografts demonstrated that these cells express a gene program similar to that of normal intestinal stem cells and that they propagate the disease to recipient mice very efficiently. Lineage-tracing experiments showed that LGR5+ CRC cells self-renew and generate progeny over long time periods that undergo differentiation toward mucosecreting- and absorptive-like phenotypes. These genetic experiments confirm that human CRCs adopt a hierarchical organization reminiscent of that of the normal colonic epithelium. The strategy described herein may have broad applications to study cell heterogeneity in human tumors.


Assuntos
Técnicas de Cultura de Células/métodos , Neoplasias Colorretais/fisiopatologia , Células-Tronco Neoplásicas/fisiologia , Organoides , Animais , Diferenciação Celular , Proliferação de Células , Feminino , Edição de Genes/métodos , Técnicas de Introdução de Genes , Genes Reporter , Proteínas de Fluorescência Verde/análise , Proteínas de Fluorescência Verde/genética , Xenoenxertos , Humanos , Camundongos SCID , Receptores Acoplados a Proteínas G/genética , Coloração e Rotulagem/métodos
10.
Innovations (Phila) ; 10(5): 342-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26536078

RESUMO

OBJECTIVE: Paraplegia remains the most feared and a devastating complication after descending and thoracoabdominal aneurysm operative repair (DTA and TAAAR). Neuromonitoring, particularly use of motor-evoked potentials (MEPs), for this surgery has gained popularity. However, ambiguity remains regarding its use and benefit. We systematically reviewed the literature to assess the benefit and applicability of neuromonitoring in DTA and TAAAR. METHODS: Electronic searches were performed on 4 major databases from inception until February 2014 to identify relevant studies. Eligibility decisions, method quality, data extraction, and analysis were performed according to predefined clinical criteria and end points. RESULTS: Among the studies matching our inclusion criteria, 1297 patients had MEP monitoring during DTA and TAAAR. In-hospital mortality was low (6.9% ± 3.6). Immediate neurological deficit was low (3.5% ± 2.6). In one third of patients (30.4% ± 14.2), the MEPs dropped below threshold, which were 30.4% and 29.4% with threshold levels of 75% and 50%, respectively. A range of surgical techniques were applied after reduction in MEPs. Most patients whose MEPs dropped and remained below threshold had immediate permanent neurological deficit (92.0% ± 23.6). Somatosensory-evoked potentials were reported in one third of papers with little association between loss of somatosensory-evoked potentials and permanent neurological deficit (16.7% ± 28.9%). CONCLUSIONS: We demonstrate that MEPs are useful at predicting paraplegia in patients who lose their MEPs and do not regain them intraoperatively. To date, there is no consensus regarding the applicability and use of MEPs. Current evidence does not mandate or support MEP use.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Monitorização Neurofisiológica Intraoperatória , Aneurisma da Aorta Torácica/fisiopatologia , Humanos , Monitorização Neurofisiológica Intraoperatória/métodos , Paraplegia/etiologia
11.
Nat Genet ; 47(4): 320-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25706628

RESUMO

Recent molecular classifications of colorectal cancer (CRC) based on global gene expression profiles have defined subtypes displaying resistance to therapy and poor prognosis. Upon evaluation of these classification systems, we discovered that their predictive power arises from genes expressed by stromal cells rather than epithelial tumor cells. Bioinformatic and immunohistochemical analyses identify stromal markers that associate robustly with disease relapse across the various classifications. Functional studies indicate that cancer-associated fibroblasts (CAFs) increase the frequency of tumor-initiating cells, an effect that is dramatically enhanced by transforming growth factor (TGF)-ß signaling. Likewise, we find that all poor-prognosis CRC subtypes share a gene program induced by TGF-ß in tumor stromal cells. Using patient-derived tumor organoids and xenografts, we show that the use of TGF-ß signaling inhibitors to block the cross-talk between cancer cells and the microenvironment halts disease progression.


Assuntos
Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Fibroblastos/metabolismo , Células-Tronco Neoplásicas/metabolismo , Animais , Análise por Conglomerados , Neoplasias Colorretais/classificação , Neoplasias Colorretais/patologia , Fibroblastos/patologia , Regulação Neoplásica da Expressão Gênica , Células HT29 , Humanos , Camundongos , Camundongos Nus , Análise em Microsséries , Invasividade Neoplásica , Metástase Neoplásica , Células-Tronco Neoplásicas/patologia , Prognóstico , Células Estromais/metabolismo , Células Estromais/patologia , Transcriptoma
12.
EMBO Rep ; 15(11): 1210-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25296644

RESUMO

Activating mutations in Wnt and EGFR/Ras signaling pathways are common in colorectal cancer (CRC). Remarkably, clonal co-activation of these pathways in the adult Drosophila midgut induces "tumor-like" overgrowths. Here, we show that, in these clones and in CRC cell lines, Dpp/TGF-ß acts as a tumor suppressor. Moreover, we discover that the Iroquois/IRX-family-protein Mirror downregulates the transcription of core components of the Dpp pathway, reducing its tumor suppressor activity. We also show that this genetic interaction is conserved in human CRC cells, where the Iro/IRX proteins IRX3 and IRX5 diminish the response to TGF-ß. IRX3 and IRX5 are upregulated in human adenomas, and their levels correlate inversely with the gene expression signature of response to TGF-ß. In addition, Irx5 expression confers a growth advantage in the presence of TGF-ß, but is selected against in its absence. Together, our results identify a set of Iro/IRX proteins as conserved negative regulators of Dpp/TGF-ß activity. We propose that during the characteristic adenoma-to-carcinoma transition of human CRC, the activity of IRX proteins could reduce the sensitivity to the cytostatic effect of TGF-ß, conferring a growth advantage to tumor cells prior to the acquisition of mutations in TGF-ß pathway components.


Assuntos
Adenocarcinoma/metabolismo , Carcinogênese/metabolismo , Neoplasias Colorretais/metabolismo , Proteínas de Homeodomínio/metabolismo , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Carcinogênese/genética , Linhagem Celular Tumoral , Células Cultivadas , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Proteínas de Homeodomínio/genética , Humanos , Mucosa Intestinal/metabolismo , Fatores de Transcrição/genética , Fator de Crescimento Transformador beta/genética , Regulação para Cima
13.
Nat Cell Biol ; 16(7): 695-707, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24952462

RESUMO

Aberrant activation of WNT signalling and loss of BMP signals represent the two main alterations leading to the initiation of colorectal cancer (CRC). Here we screen for genes required for maintaining the tumour stem cell phenotype and identify the zinc-finger transcription factor GATA6 as a key regulator of the WNT and BMP pathways in CRC. GATA6 directly drives the expression of LGR5 in adenoma stem cells whereas it restricts BMP signalling to differentiated tumour cells. Genetic deletion of Gata6 from mouse colon adenomas increases the levels of BMP factors, which signal to block self-renewal of tumour stem cells. In human tumours, GATA6 competes with ß-catenin/TCF4 for binding to a distal regulatory region of the BMP4 locus that has been linked to increased susceptibility to development of CRC. Hence, GATA6 creates an environment permissive for CRC initiation by lowering the threshold of BMP signalling required for tumour stem cell expansion.


Assuntos
Adenoma , Receptores de Proteínas Morfogenéticas Ósseas/genética , Neoplasias Colorretais/fisiopatologia , Fator de Transcrição GATA6/metabolismo , Regulação Neoplásica da Expressão Gênica , Células-Tronco/citologia , Células-Tronco/metabolismo , Adenoma/patologia , Animais , Antineoplásicos/farmacologia , Receptores de Proteínas Morfogenéticas Ósseas/metabolismo , Proliferação de Células , Feminino , Imunofluorescência , Fator de Transcrição GATA6/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Camundongos , Pirazóis/farmacologia , Pirimidinas/farmacologia , Células-Tronco/efeitos dos fármacos , Proteínas Wnt/metabolismo
14.
Aorta (Stamford) ; 2(1): 10-21, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26798710

RESUMO

UNLABELLED: Background : It is widely accepted that aortic valve disease is surgically managed with aortic valve replacement (AVR) using different available prostheses. The long-term survival, durability of the valve, and freedom from reoperation after AVR are well established in published literature. Over the past two decades, aortic valve repair (AVr) has evolved into an accepted surgical option for patients with aortic valve disease. We review and analyze the published literature on AVr. Methods : A systematic review of the current literature was performed through three electronic databases from inception to August 2013 to identify all relevant studies relating to aortic valve repair. Articles selected were chosen by two reviewers. Articles were excluded if they contained a pediatric population or if the patient number was less than 50. RESULTS: Twenty-four studies conformed to the inclusion criteria for inclusion in the systematic review. In total, 4986 patients underwent aortic valve repair. 7 studies represented bicuspid aortic valve (BAV) repair, 5 studies represented cusp prolapse, and 3 studies represented valve repair with root dilation or aneurysm. Overall weighted in-hospital mortality for all studies was low (1.46% ± 1.21). Preoperative aortic insufficiency (AI) ≥ 2+ did not correlate to reoperation for valve failure (Pearson's Rs 0.2705, P = 0.2585). AI at discharge was reported in 9 studies with a mean AI ≥ 2+ in 6.1% of patients. Weighted average percentage for valve reoperation following BAV repair was 10.23% ± 3.2. Weighted average reoperation following cusp prolapse repair was 3.83 ± 1.96. Weighted average reoperation in aortic valve sparing procedures with root replacement was 4.25% ± 2.46. Although there are limitations and complications of prosthetic valves, especially for younger individuals, there is ample published literature that confers strong evidence for AVR. On the contrary, aortic valve repair may be a useful option for selected patients, but there is lack of uniformity in data and absence of compelling supporting evidence. An international multi-center study comparing and assessing the results between AVR & AVr is the next step required. Currently, higher levels of evidence do not exist for aortic valve repair.

15.
Bio Protoc ; 4(9)2014 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-29104885

RESUMO

We sought to understand the mechanisms behind the potent effect of stromal TGF-beta program on the capacity of colorectal cancer (CRC) cells to initiate metastasis. We discovered that mice subcutaneous tumors and metastases generated in the context of a TGF-beta activated microenvironment displayed prominent accumulation of p-STAT3 in CRC cells compared with those derived from control cells. STAT3 signaling depended on GP130 as shown by strong reduction of epithelial p STAT3 levels upon GP130 shRNA-mediated knockdown in CRC cells.

16.
Cancer Cell ; 22(5): 571-84, 2012 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-23153532

RESUMO

A large proportion of colorectal cancers (CRCs) display mutational inactivation of the TGF-ß pathway, yet, paradoxically, they are characterized by elevated TGF-ß production. Here, we unveil a prometastatic program induced by TGF-ß in the microenvironment that associates with a high risk of CRC relapse upon treatment. The activity of TGF-ß on stromal cells increases the efficiency of organ colonization by CRC cells, whereas mice treated with a pharmacological inhibitor of TGFBR1 are resilient to metastasis formation. Secretion of IL11 by TGF-ß-stimulated cancer-associated fibroblasts (CAFs) triggers GP130/STAT3 signaling in tumor cells. This crosstalk confers a survival advantage to metastatic cells. The dependency on the TGF-ß stromal program for metastasis initiation could be exploited to improve the diagnosis and treatment of CRC.


Assuntos
Neoplasias Colorretais/patologia , Fator de Crescimento Transformador beta/fisiologia , Animais , Neoplasias Colorretais/tratamento farmacológico , Receptor gp130 de Citocina/genética , Receptor gp130 de Citocina/metabolismo , Receptor gp130 de Citocina/fisiologia , Células HT29 , Humanos , Interleucina-11/genética , Interleucina-11/metabolismo , Interleucina-11/fisiologia , Camundongos , Metástase Neoplásica/tratamento farmacológico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/antagonistas & inibidores , Recidiva , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/fisiologia , Transdução de Sinais , Células Estromais/metabolismo , Células Estromais/patologia , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Células Tumorais Cultivadas , Microambiente Tumoral
17.
Cell Stem Cell ; 8(5): 511-24, 2011 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-21419747

RESUMO

A frequent complication in colorectal cancer (CRC) is regeneration of the tumor after therapy. Here, we report that a gene signature specific for adult intestinal stem cells (ISCs) predicts disease relapse in CRC patients. ISCs are marked by high expression of the EphB2 receptor, which becomes gradually silenced as cells differentiate. Using EphB2 and the ISC marker Lgr5, we have FACS-purified and profiled mouse ISCs, crypt proliferative progenitors, and late transient amplifying cells to define a gene program specific for normal ISCs. Furthermore, we discovered that ISC-specific genes identify a stem-like cell population positioned at the bottom of tumor structures reminiscent of crypts. EphB2 sorted ISC-like tumor cells display robust tumor-initiating capacity in immunodeficient mice as well as long-term self-renewal potential. Taken together, our data suggest that the ISC program defines a cancer stem cell niche within colorectal tumors and plays a central role in CRC relapse.


Assuntos
Células-Tronco Adultas/metabolismo , Neoplasias do Colo/diagnóstico , Intestinos/patologia , Células-Tronco Neoplásicas/metabolismo , Receptor EphB3/metabolismo , Células-Tronco Adultas/patologia , Animais , Diferenciação Celular , Separação Celular , Extensões da Superfície Celular/patologia , Células Cultivadas , Neoplasias do Colo/patologia , Neoplasias do Colo/fisiopatologia , Citometria de Fluxo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Camundongos , Camundongos Knockout , Recidiva Local de Neoplasia , Células-Tronco Neoplásicas/patologia , Prognóstico , Receptor EphB3/genética , Receptores Acoplados a Proteínas G/metabolismo , Nicho de Células-Tronco
18.
Nat Genet ; 39(11): 1376-83, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17906625

RESUMO

The genes encoding tyrosine kinase receptors EphB2 and EphB3 are beta-catenin and Tcf4 target genes in colorectal cancer (CRC) and in normal intestinal cells. In the intestinal epithelium, EphB signaling controls the positioning of cell types along the crypt-villus axis. In CRC, EphB activity suppresses tumor progression beyond the earliest stages. Here we show that EphB receptors compartmentalize the expansion of CRC cells through a mechanism dependent on E-cadherin-mediated adhesion. We demonstrate that EphB-mediated compartmentalization restricts the spreading of EphB-expressing tumor cells into ephrin-B1-positive territories in vitro and in vivo. Our results indicate that CRC cells must silence EphB expression to avoid repulsive interactions imposed by normal ephrin-B1-expressing intestinal cells at the onset of tumorigenesis.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/prevenção & controle , Efrina-B1/metabolismo , Regulação Neoplásica da Expressão Gênica , Adenoma/metabolismo , Adenoma/patologia , Adenoma/prevenção & controle , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Progressão da Doença , Efrina-B1/antagonistas & inibidores , Efrina-B1/genética , Feminino , Genes APC/fisiologia , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Neoplasias Intestinais/metabolismo , Neoplasias Intestinais/patologia , Neoplasias Intestinais/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores da Família Eph/antagonistas & inibidores , Receptores da Família Eph/genética , Receptores da Família Eph/metabolismo , Transdução de Sinais , Frações Subcelulares , Fatores de Transcrição TCF/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição , beta Catenina/metabolismo
19.
Mol Cell Biol ; 26(22): 8418-26, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16954380

RESUMO

Inhibition of the mutationally activated Wnt cascade in colorectal cancer cell lines induces a rapid G1 arrest and subsequent differentiation. This arrest can be overcome by maintaining expression of a single Tcf4 target gene, the proto-oncogene c-Myc. Since colorectal cancer cells share many molecular characteristics with proliferative crypt progenitors, we have assessed the physiological role of c-Myc in adult crypts by conditional gene deletion. c-Myc-deficient crypts are lost within weeks and replaced by c-Myc-proficient crypts through a fission process of crypts that have escaped gene deletion. Although c-Myc(-/-) crypt cells remain in the cell cycle, they are on average much smaller than wild-type cells, cycle slower, and divide at a smaller cell size. c-Myc appears essential for crypt progenitor cells to provide the necessary biosynthetic capacity to successfully progress through the cell cycle.


Assuntos
Neoplasias Colorretais/metabolismo , Genes myc , Intestinos/patologia , Proteínas Proto-Oncogênicas c-myc/genética , Fatores de Transcrição TCF/genética , Proteínas Wnt/genética , Animais , Apoptose , Contagem de Células , Neoplasias Colorretais/patologia , Epitélio/fisiologia , Marcação de Genes , Integrases/genética , Mucosa Intestinal/metabolismo , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Mitose , Proteína 2 Semelhante ao Fator 7 de Transcrição
20.
Nature ; 435(7045): 1126-30, 2005 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-15973414

RESUMO

Most sporadic colorectal cancers are initiated by activating Wnt pathway mutations, characterized by the stabilization of beta-catenin and constitutive transcription by the beta-catenin/T cell factor-4 (Tcf-4) complex. EphB guidance receptors are Tcf4 target genes that control intestinal epithelial architecture through repulsive interactions with Ephrin-B ligands. Here we show that, although Wnt signalling remains constitutively active, most human colorectal cancers lose expression of EphB at the adenoma-carcinoma transition. Loss of EphB expression strongly correlates with degree of malignancy. Furthermore, reduction of EphB activity accelerates tumorigenesis in the colon and rectum of Apc(Min/+) mice, and results in the formation of aggressive adenocarcinomas. Our data demonstrate that loss of EphB expression represents a critical step in colorectal cancer progression.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Receptores da Família Eph/metabolismo , Adenoma/metabolismo , Adenoma/patologia , Animais , Linhagem Celular Tumoral , Progressão da Doença , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Genes APC , Genes Dominantes/genética , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Camundongos , Camundongos Transgênicos , Mutação/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores da Família Eph/deficiência , Receptores da Família Eph/genética , Transdução de Sinais , Proteínas Wnt
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