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1.
Nat Commun ; 12(1): 5006, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34408135

RESUMO

Obesity is a strong risk factor for cancer progression, posing obesity-related cancer as one of the leading causes of death. Nevertheless, the molecular mechanisms that endow cancer cells with metastatic properties in patients affected by obesity remain unexplored.Here, we show that IL-6 and HGF, secreted by tumor neighboring visceral adipose stromal cells (V-ASCs), expand the metastatic colorectal (CR) cancer cell compartment (CD44v6 + ), which in turn secretes neurotrophins such as NGF and NT-3, and recruits adipose stem cells within tumor mass. Visceral adipose-derived factors promote vasculogenesis and the onset of metastatic dissemination by activation of STAT3, which inhibits miR-200a and enhances ZEB2 expression, effectively reprogramming CRC cells into a highly metastatic phenotype. Notably, obesity-associated tumor microenvironment provokes a transition in the transcriptomic expression profile of cells derived from the epithelial consensus molecular subtype (CMS2) CRC patients towards a mesenchymal subtype (CMS4). STAT3 pathway inhibition reduces ZEB2 expression and abrogates the metastatic growth sustained by adipose-released proteins. Together, our data suggest that targeting adipose factors in colorectal cancer patients with obesity may represent a therapeutic strategy for preventing metastatic disease.


Assuntos
Tecido Adiposo/citologia , Reprogramação Celular , Neoplasias do Colo/fisiopatologia , Células-Tronco Neoplásicas/citologia , Nicho de Células-Tronco , Tecido Adiposo/metabolismo , Animais , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Fator de Crescimento de Hepatócito/genética , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Masculino , Camundongos , Camundongos SCID , MicroRNAs/genética , MicroRNAs/metabolismo , Metástase Neoplásica , Células-Tronco/citologia , Células-Tronco/metabolismo , Homeobox 2 de Ligação a E-box com Dedos de Zinco/genética , Homeobox 2 de Ligação a E-box com Dedos de Zinco/metabolismo
2.
Cancers (Basel) ; 13(16)2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34439086

RESUMO

Colorectal cancer (CRC) mortality is mainly caused by patient refractoriness to common anti-cancer therapies and consequent metastasis formation. Besides, the notorious toxic side effects of chemotherapy are a concurrent obstacle to be tackled. Thus, new treatment approaches are needed to effectively improve patient outcomes. Compelling evidence demonstrated that cancer stem cells (CSCs) are responsible for treatment failure and relapse. New natural treatment approaches showed capabilities to selectively target the CSC subpopulation by rendering them targetable by standard cytotoxic compounds. Herein we show the anti-cancer properties of the polymethoxyflavones and prenylflavonoids extracted from Citrus sinensis and Humulus lupulus, respectively. The natural biofunctional fractions, singularly and in combination, reduced the cell viability of CRC stem cells (CR-CSCs) and synergized with 5-fluorouracil and oxaliplatin (FOX) chemotherapy. These phenomena were accompanied by a reduced S and G2/M phase of the cell cycle and upregulation of cell death-related genes. Notably, both phytoextracts in combination with FOX thwarted stemness features in CR-CSCs as demonstrated by the impaired clonogenic potential and decreased Wnt pathway activation. Extracts lowered the expression of CD44v6 and affected the expansion of metastatic CR-CSCs in patients refractory to chemotherapy. Together, this study highlights the importance of polymethoxyflavones and prenylflavonoids as natural remedies to aid oncological therapies.

3.
iScience ; 24(6): 102664, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34169240

RESUMO

Limited therapeutic options are available for advanced colorectal cancer (CRC). Herein, we report that exposure to a neo-synthetic bis(indolyl)thiazole alkaloid analog, nortopsentin 234 (NORA234), leads to an initial reduction of proliferative and clonogenic potential of CRC sphere cells (CR-CSphCs), followed by an adaptive response selecting the CR-CSphC-resistant compartment. Cells spared by the treatment with NORA234 express high levels of CD44v6, associated with a constitutive activation of Wnt pathway. In CR-CSphC-based organoids, NORA234 causes a genotoxic stress paralleled by G2-M cell cycle arrest and activation of CHK1, driving the DNA damage repair of CR-CSphCs, regardless of the mutational background, microsatellite stability, and consensus molecular subtype. Synergistic combination of NORA234 and CHK1 (rabusertib) targeting is synthetic lethal inducing death of both CD44v6-negative and CD44v6-positive CRC stem cell fractions, aside from Wnt pathway activity. These data could provide a rational basis to develop an effective strategy for the treatment of patients with CRC.

4.
Cell Death Dis ; 12(4): 316, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33767160

RESUMO

The prognosis of locally advanced colorectal cancer (CRC) is currently unsatisfactory. This is mainly due to drug resistance, recurrence, and subsequent metastatic dissemination, which are sustained by the cancer stem cell (CSC) population. The main driver of the CSC gene expression program is Wnt signaling, and previous reports indicate that Wnt3a can activate p38 MAPK. Besides, p38 was shown to feed into the canonical Wnt/ß-catenin pathway. Here we show that patient-derived locally advanced CRC stem cells (CRC-SCs) are characterized by increased expression of p38α and are "addicted" to its kinase activity. Of note, we found that stage III CRC patients with high p38α levels display reduced disease-free and progression-free survival. Extensive molecular analysis in patient-derived CRC-SC tumorspheres and APCMin/+ mice intestinal organoids revealed that p38α acts as a ß-catenin chromatin-associated kinase required for the regulation of a signaling platform involved in tumor proliferation, metastatic dissemination, and chemoresistance in these CRC model systems. In particular, the p38α kinase inhibitor ralimetinib, which has already entered clinical trials, promoted sensitization of patient-derived CRC-SCs to chemotherapeutic agents commonly used for CRC treatment and showed a synthetic lethality effect when used in combination with the MEK1 inhibitor trametinib. Taken together, these results suggest that p38α may be targeted in CSCs to devise new personalized CRC treatment strategies.


Assuntos
Cromatina/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Células-Tronco Neoplásicas/metabolismo , Organoides/metabolismo , Processamento de Proteína Pós-Traducional/genética , beta Catenina/metabolismo , Neoplasias Colorretais/genética , Humanos , Prognóstico
5.
Gut ; 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33436496

RESUMO

OBJECTIVE: Cancer stem cells are responsible for tumour spreading and relapse. Human epidermal growth factor receptor 2 (HER2) expression is a negative prognostic factor in colorectal cancer (CRC) and a potential target in tumours carrying the gene amplification. Our aim was to define the expression of HER2 in colorectal cancer stem cells (CR-CSCs) and its possible role as therapeutic target in CRC resistant to anti- epidermal growth factor receptor (EGFR) therapy. DESIGN: A collection of primary sphere cell cultures obtained from 60 CRC specimens was used to generate CR-CSC mouse avatars to preclinically validate therapeutic options. We also made use of the ChIP-seq analysis for transcriptional evaluation of HER2 activation and global RNA-seq to identify the mechanisms underlying therapy resistance. RESULTS: Here we show that in CD44v6-positive CR-CSCs, high HER2 expression levels are associated with an activation of the phosphatidylinositol 3-kinase (PI3K)/AKT pathway, which promotes the acetylation at the regulatory elements of the Erbb2 gene. HER2 targeting in combination with phosphatidylinositol 3-kinase (PI3K) and mitogen-activated protein kinase kinase (MEK) inhibitors induces CR-CSC death and regression of tumour xenografts, including those carrying Kras and Pik3ca mutation. Requirement for the triple targeting is due to the presence of cancer-associated fibroblasts, which release cytokines able to confer CR-CSC resistance to PI3K/AKT inhibitors. In contrast, targeting of PI3K/AKT as monotherapy is sufficient to kill liver-disseminating CR-CSCs in a model of adjuvant therapy. CONCLUSIONS: While PI3K targeting kills liver-colonising CR-CSCs, the concomitant inhibition of PI3K, HER2 and MEK is required to induce regression of tumours resistant to anti-EGFR therapies. These data may provide a rationale for designing clinical trials in the adjuvant and metastatic setting.

7.
Stem Cell Res Ther ; 8(1): 236, 2017 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-29058626

RESUMO

BACKGROUND: The use of stem cells, including mesenchymal stem cells (MSCs), for regenerative medicine is gaining interest for the clinical benefits so far obtained in patients. This study investigates the use of adipose autologous tissue in combination with platelet-rich plasma (PRP) to improve the clinical outcome of patients affected by systemic sclerosis (SSc). METHODS: Adipose-derived mesenchymal stem cells (AD-MSCs) and PRPs were purified from healthy donors and SSc patients. The multilineage differentiation potential of AD-MSCs and their genotypic-phenotypic features were investigated. A cytokine production profile was evaluated on AD-MSCs and PRPs from both healthy subjects and SSc patients. The adipose tissue-derived cell fraction, the so-called stromal vascular fraction (SVF), was coinjected with PRP in the perioral area of SSc patients. RESULTS: Histopathological and phenotypical analysis of adipose tissue from SSc patients revealed a disorganization of its distinct architecture coupled with an altered cell composition. Although AD-MSCs derived from SSc patients showed high multipotency, they failed to sustain a terminally differentiated progeny. Furthermore, SVFs derived from SSc patients differed from healthy donors in their MSC-like traits coupled with an aberrant cytokine production profile. Finally, the administration of PRP in combination with autologous SVF improved buccal's rhyme, skin elasticity and vascularization for all of the SSc patients enrolled in this study. CONCLUSIONS: This innovative regenerative therapy could be exploited for the treatment of chronic connective tissue diseases, including SSc.


Assuntos
Tecido Adiposo/citologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Plasma Rico em Plaquetas/fisiologia , Medicina Regenerativa/métodos , Escleroderma Sistêmico/terapia , Tecido Adiposo/imunologia , Adulto , Idoso de 80 Anos ou mais , Antígenos CD/genética , Antígenos CD/imunologia , Diferenciação Celular , Proliferação de Células , Terapia Baseada em Transplante de Células e Tecidos/métodos , Citocinas/genética , Citocinas/imunologia , Feminino , Expressão Gênica , Humanos , Masculino , Células-Tronco Mesenquimais/imunologia , Pessoa de Meia-Idade , Neovascularização Fisiológica , Cultura Primária de Células , Escleroderma Sistêmico/imunologia , Escleroderma Sistêmico/patologia , Pele/patologia
8.
Cancer Immunol Res ; 5(5): 397-407, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28351891

RESUMO

The identification of reciprocal interactions between tumor-infiltrating immune cells and the microenviroment may help us understand mechanisms of tumor growth inhibition or progression. We have assessed the frequencies of tumor-infiltrating and circulating γδ T cells and regulatory T cells (Treg) from 47 patients with squamous cell carcinoma (SCC), to determine if they correlated with progression or survival. Vδ1 T cells infiltrated SSC tissue to a greater extent than normal skin, but SCC patients and healthy subjects had similar amounts circulating. However, Vδ2 T cells were present at higher frequencies in circulation than in the tissue of either cancer patients or healthy donors. Tregs were decreased in the peripheral blood of SCC patients, but were significantly increased in the tumor compartment of these patients. Tumor-infiltrating γδ T cells preferentially showed an effector memory phenotype and made either IL17 or IFNγ depending on the tumor stage, whereas circulating γδ T cells of SCC patients preferentially made IFNγ. Different cell types in the tumor microenvironment produced chemokines that could recruit circulating γδ T cells to the tumor site and other cytokines that could reprogram γδ T cells to produce IL17. These findings suggest the possibility that γδ T cells in SCC are recruited from the periphery and their features are then affected by the tumor microenvironment. Elevated frequencies of infiltrating Vδ2 T cells and Tregs differently correlated with early and advanced tumor stages, respectively. Our results provide insights into the functions of tumor-infiltrating γδ T cells and define potential tools for tumor immunotherapy. Cancer Immunol Res; 5(5); 397-407. ©2017 AACR.


Assuntos
Carcinoma de Células Escamosas/imunologia , Linfócitos do Interstício Tumoral/imunologia , Neoplasias Cutâneas/imunologia , Subpopulações de Linfócitos T/imunologia , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Citocinas/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Cutâneas/patologia , Microambiente Tumoral
9.
Oncotarget ; 7(34): 54157-54173, 2016 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-27494839

RESUMO

P63 is a transcription factor belonging to the family of p53, essential for the development and differentiation of epithelia. In recent years, it has become clear that altered expression of the different isoforms of this gene can play an important role in carcinogenesis. The p63 gene encodes for two main isoforms known as TA and ΔN p63 with different functions. The role of these different isoforms in sustaining tumor progression and metastatic spreading however has not entirely been clarified. Here we show that breast cancer initiating cells express ΔNp63 isoform that supports a more mesenchymal phenotype associated with a higher tumorigenic and metastatic potential. On the contrary, the majority of cells within the tumor appears to express predominantly TAp63 isoform. While ΔNp63 exerts its effects by regulating a PI3K/CD44v6 pathway, TAp63 modulates this pathway in an opposite fashion. As a result, tumorigenicity and invasive capacity of breast cancer cells is a balance of the two isoforms. Finally, we found that tumor microenvironmental cytokines significantly contribute to the establishment of breast cancer cell phenotype by positively regulating ΔNp63 and CD44v6 expression.


Assuntos
Neoplasias da Mama/patologia , Receptores de Hialuronatos/fisiologia , Proteínas de Membrana/fisiologia , Fosfatidilinositol 3-Quinases/fisiologia , Idoso , Idoso de 80 Anos ou mais , Animais , Neoplasias da Mama/genética , Resistencia a Medicamentos Antineoplásicos , Transição Epitelial-Mesenquimal , Feminino , Humanos , Camundongos , Pessoa de Meia-Idade , Metástase Neoplásica , Proteínas Proto-Oncogênicas c-akt/fisiologia , Transdução de Sinais/fisiologia , Microambiente Tumoral
10.
Oncotarget ; 6(4): 2315-30, 2015 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-25537513

RESUMO

Basal-like breast cancer is an aggressive tumor subtype with a poor response to conventional therapies. Tumor formation and relapse are sustained by a cell subset of Breast Cancer Stem Cells (BrCSCs). Here we show that miR-100 inhibits maintenance and expansion of BrCSCs in basal-like cancer through Polo-like kinase1 (Plk1) down-regulation. Moreover, miR-100 favors BrCSC differentiation, converting a basal like phenotype into luminal. It induces the expression of a functional estrogen receptor (ER) and renders basal-like BrCSCs responsive to hormonal therapy. The key role played by miR-100 in breast cancer free-survival is confirmed by the analysis of a cohort of patients' tumors, which shows that low expression of miR-100 is a negative prognostic factor and is associated with gene signatures of high grade undifferentiated tumors. Our findings indicate a new possible therapeutic strategy, which could make aggressive breast cancers responsive to standard treatments.


Assuntos
Neoplasias da Mama/genética , Diferenciação Celular/genética , MicroRNAs/genética , Células-Tronco Neoplásicas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Células MCF-7 , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Prognóstico , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tamoxifeno/farmacologia , Transplante Heterólogo
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