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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
3.
ACS Appl Mater Interfaces ; 13(14): 15959-15972, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33797220

RESUMO

Cancer stem cells (CSCs) are the tumor cell subpopulation responsible for resistance to chemotherapy, tumor recurrence, and metastasis. An efficient therapy must act on low proliferating quiescent-CSCs (q-CSCs). We here investigate the effect of magnetic hyperthermia (MHT) in combination with local chemotherapy as a dual therapy to inhibit patient-derived colorectal qCR-CSCs. We apply iron oxide nanocubes as MHT heat mediators, coated with a thermoresponsive polymer (TR-Cubes) and loaded with DOXO (TR-DOXO) as a chemotherapeutic agent. The thermoresponsive polymer releases DOXO only at a temperature above 44 °C. In colony-forming assays, the cells exposed to TR-Cubes with MHT reveal that qCR-CSCs struggle to survive the heat damage and, with a due delay, restart the division of dormant cells. The eradication of qCR-CSCs with a complete stop of the colony formation was achieved only with TR-DOXO when exposed to MHT. The in vivo tumor formation study confirms the combined effects of MHT with heat-mediated drug release: only the group of animals that received the CR-CSCs pretreated, in vitro, with TR-DOXO and MHT lacked the formation of tumor even after several months. For DOXO-resistant CR-CSCs cells, the same results were shown, in vitro, when choosing the drug oxaliplatin rather than DOXO and applying MHT. These findings emphasize the potential of our nanoplatforms as an effective patient-personalized cancer treatment against qCR-CSCs.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Neoplasias Colorretais/patologia , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos , Hipertermia Induzida , Nanopartículas de Magnetita/química , Células-Tronco Neoplásicas/patologia , Terapia Combinada , Humanos
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
6.
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.
Oncogene ; 39(5): 987-1003, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31591478

RESUMO

Despite intense research and clinical efforts, patients affected by advanced colorectal cancer (CRC) have still a poor prognosis. The discovery of colorectal (CR) cancer stem cell (CSC) as the cell compartment responsible for tumor initiation and propagation may provide new opportunities for the development of new therapeutic strategies. Given the reduced sensitivity of CR-CSCs to chemotherapy and the ability of bone morphogenetic proteins (BMP) to promote colonic stem cell differentiation, we aimed to investigate whether an enhanced variant of BMP7 (BMP7v) could sensitize to chemotherapy-resistant CRC cells and tumors. Thirty-five primary human cultures enriched in CR-CSCs, including four from chemoresistant metastatic lesions, were used for in vitro studies and to generate CR-CSC-based mouse avatars to evaluate tumor growth and progression upon treatment with BMP7v alone or in combination with standard therapy or PI3K inhibitors. BMP7v treatment promotes CR-CSC differentiation and recapitulates the cell differentiation-related gene expression profile by suppressing Wnt pathway activity and reducing mesenchymal traits and survival of CR-CSCs. Moreover, in CR-CSC-based mouse avatars, BMP7v exerts an antiangiogenic effect and sensitizes tumor cells to standard chemotherapy regardless of the mutational, MSI, and CMS profiles. Of note, tumor harboring PIK3CA mutations were affected to a lower extent by the combination of BMP7v and chemotherapy. However, the addition of a PI3K inhibitor to the BMP7v-based combination potentiates PIK3CA-mutant tumor drug response and reduces the metastatic lesion size. These data suggest that BMP7v treatment may represent a useful antiangiogenic and prodifferentiation agent, which renders CSCs sensitive to both standard and targeted therapies.


Assuntos
Proteína Morfogenética Óssea 7/genética , Proteína Morfogenética Óssea 7/farmacologia , Neoplasias Colorretais/patologia , Mutação , Animais , Antineoplásicos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Humanos , Camundongos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Epigenomics ; 11(6): 587-604, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31066579

RESUMO

Aim: To investigate the genome-wide methylation of genetically characterized colorectal cancer stem cell (CR-CSC) lines. Materials & methods: Eight CR-CSC lines were isolated from primary colorectal cancer (CRC) tissues, cultured and characterized for aneuploidy, mutational status of CRC-related genes and microsatellite instability (MSI). Genome-wide DNA methylation was assessed by MethylationEPIC microarray. Results: We describe a distinctive methylation pattern that is maintained following in vivo passages in immune-compromised mice. We identified an epigenetic CR-CSC signature associated with MSI. We noticed that the preponderance of the differentially methylated positions do not reside at CpG islands, but spread to shelf and open sea regions. Conclusion: Given that CRCs with MSI-high status have a lower metastatic potential, the identification of a MSI-related methylation signature could provide new insights and possible targets into metastatic CRC.


Assuntos
Neoplasias do Colo/genética , Metilação de DNA , Instabilidade de Microssatélites , Células-Tronco Neoplásicas/patologia , Animais , Neoplasias do Colo/patologia , Ilhas de CpG/genética , Resistencia a Medicamentos Antineoplásicos/genética , Epigênese Genética , Xenoenxertos , Humanos , Camundongos
9.
Mol Cancer ; 18(1): 70, 2019 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-30927908

RESUMO

In the last decades, the role of the microenvironment in tumor progression and therapeutic outcome has gained increasing attention. Cancer-associated fibroblasts (CAFs) have emerged as key players among stromal cells, owing to their abundance in most solid tumors and their diverse tumor-restraining/promoting roles. The interplay between tumor cells and neighboring CAFs takes place by both paracrine signals (cytokines, exosomes and metabolites) or by the multifaceted functions of the surrounding extracellular matrix. Here, we dissect the most recent identified mechanisms underlying CAF-mediated control of tumor progression and therapy resistance, which include induction of the epithelial-to-mesenchymal transition (EMT), activation of survival pathways or stemness-related programs and metabolic reprogramming in tumor cells. Importantly, the recently unveiled heterogeneity in CAFs claims tailored therapeutic efforts aimed at eradicating the specific subset facilitating tumor progression, therapy resistance and relapse. However, despite the large amount of pre-clinical data, much effort is still needed to translate CAF-directed anti-cancer strategies from the bench to the clinic.


Assuntos
Fibroblastos Associados a Câncer/metabolismo , Resistencia a Medicamentos Antineoplásicos , Neoplasias/metabolismo , Antineoplásicos/farmacologia , Fibroblastos Associados a Câncer/efeitos dos fármacos , Progressão da Doença , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/tratamento farmacológico , Comunicação Parácrina , Transdução de Sinais , Microambiente Tumoral
10.
Gut ; 67(5): 903-917, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28389531

RESUMO

OBJECTIVE: Cancer stem cells (CSCs) are responsible for tumour formation and spreading, and their targeting is required for tumour eradication. There are limited therapeutic options for advanced colorectal cancer (CRC), particularly for tumours carrying RAS-activating mutations. The aim of this study was to identify novel CSC-targeting strategies. DESIGN: To discover potential therapeutics to be clinically investigated as single agent, we performed a screening with a panel of FDA-approved or investigational drugs on primary CRC cells enriched for CSCs (CRC-SCs) isolated from 27 patients. Candidate predictive biomarkers of efficacy were identified by integrating genomic, reverse-phase protein microarray (RPPA) and cytogenetic analyses, and validated by immunostainings. DNA replication stress (RS) was increased by employing DNA replication-perturbing or polyploidising agents. RESULTS: The drug-library screening led to the identification of LY2606368 as a potent anti-CSC agent acting in vitro and in vivo in tumour cells from a considerable number of patients (∼36%). By inhibiting checkpoint kinase (CHK)1, LY2606368 affected DNA replication in most CRC-SCs, including RAS-mutated ones, forcing them into premature, lethal mitoses. Parallel genomic, RPPA and cytogenetic analyses indicated that CRC-SCs sensitive to LY2606368 displayed signs of ongoing RS response, including the phosphorylation of RPA32 and ataxia telangiectasia mutated serine/threonine kinase (ATM). This was associated with mutation(s) in TP53 and hyperdiploidy, and made these CRC-SCs exquisitely dependent on CHK1 function. Accordingly, experimental increase of RS sensitised resistant CRC-SCs to LY2606368. CONCLUSIONS: LY2606368 selectively eliminates replication-stressed, p53-deficient and hyperdiploid CRC-SCs independently of RAS mutational status. These results provide a strong rationale for biomarker-driven clinical trials with LY2606368 in patients with CRC.


Assuntos
Antineoplásicos/farmacologia , Quinase 1 do Ponto de Checagem/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Pirazinas/farmacologia , Pirazóis/farmacologia , Linhagem Celular Tumoral , Quinase 1 do Ponto de Checagem/genética , Neoplasias Colorretais/genética , Replicação do DNA/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Mutação , Células-Tronco Neoplásicas/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Proteína Supressora de Tumor p53/genética
11.
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
12.
Front Immunol ; 8: 878, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28798748

RESUMO

Cancer can be considered an aberrant organ with a hierarchical composition of different cell populations. The tumor microenvironment, including the immune cells and related cytokines, is crucial during all the steps of tumor development. In particular, type I and II interferons (IFNs) are involved in a plethora of mechanisms that regulate immune responses in cancer, thus balancing immune escape versus immune surveillance. IFNs are involved in both the direct and indirect regulation of cancer cell proliferation and metastatic potential. The mutational background of genes involved in IFNs signaling could serve as a prognostic biomarker and a powerful tool to screen cancer patients eligible for checkpoint blocking therapies. We herewith describe the latest findings regarding the contribution of IFNs in colorectal cancer and melanoma by researching their dual role as either tumor promoter or suppressor, in diverse tumor types, and microenvironmental context. We are reporting the most innovative and promising approaches of IFN-based therapies that have achieved considerable outcomes in clinical oncology practice and explain the possible mechanisms responsible for their failure.

13.
Cancer Res ; 77(12): 3268-3279, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28400477

RESUMO

The tumor microenvironment supplies proinflammatory cytokines favoring a permissive milieu for cancer cell growth and invasive behavior. Here we show how breast cancer progression is facilitated by IL4 secreted by adipose tissue and estrogen receptor-positive and triple-negative breast cancer cell types. Blocking autocrine and paracrine IL4 signaling with the IL4Rα antagonist IL4DM compromised breast cancer cell proliferation, invasion, and tumor growth by downregulating MAPK pathway activity. IL4DM reduced numbers of CD44+/CD24- cancer stem-like cells and elevated expression of the dual specificity phosphatase DUSP4 by inhibiting NF-κB. Enforced expression of DUSP4 drove conversion of metastatic cells to nonmetastatic cells. Mechanistically, RNAi-mediated attenuation of DUSP4 activated the ERK and p38 MAPK pathways, increased stem-like properties, and spawned metastatic capacity. Targeting IL4 signaling sensitized breast cancer cells to anticancer therapy and strengthened immune responses by enhancing the number of IFNγ-positive CTLs. Our results showed the role of IL4 in promoting breast cancer aggressiveness and how its targeting may improve the efficacy of current therapies. Cancer Res; 77(12); 3268-79. ©2017 AACR.


Assuntos
Neoplasias da Mama/patologia , Fosfatases de Especificidade Dupla/metabolismo , Interleucina-4/metabolismo , Fosfatases da Proteína Quinase Ativada por Mitógeno/metabolismo , Microambiente Tumoral , Western Blotting , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Citometria de Fluxo , Xenoenxertos , Humanos
15.
Oncotarget ; 7(40): 65504-65513, 2016 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-27602767

RESUMO

Radiotherapy is based on the induction of lethal DNA damage, primarily DNA double-strand breaks (DSB). Efficient DSB repair via Non-Homologous End Joining or Homologous Recombination can therefore undermine the efficacy of radiotherapy. By suppressing DNA-DSB repair with hyperthermia (HT) and DNA-PKcs inhibitor NU7441 (DNA-PKcsi), we aim to enhance the effect of radiation.The sensitizing effect of HT for 1 hour at 42°C and DNA-PKcsi [1 µM] to radiation treatment was investigated in cervical and breast cancer cells, primary breast cancer sphere cells (BCSCs) enriched for cancer stem cells, and in an in vivo human tumor model. A significant radio-enhancement effect was observed for all cell types when DNA-PKcsi and HT were applied separately, and when both were combined, HT and DNA-PKcsi enhanced radio-sensitivity to an even greater extent. Strikingly, combined treatment resulted in significantly lower survival rates, 2 to 2.5 fold increase in apoptosis, more residual DNA-DSB 6 h post treatment and a G2-phase arrest. In addition, tumor growth analysis in vivo showed significant reduction in tumor growth and elevated caspase-3 activity when radiation was combined with HT and DNA-PKcsi compared to radiation alone. Importantly, no toxic side effects of HT or DNA-PKcsi were found.In conclusion, inhibiting DNA-DSB repair using HT and DNA-PKcsi before radiotherapy leads to enhanced cytotoxicity in cancer cells. This effect was even noticed in the more radio-resistant BCSCs, which are clearly sensitized by combined treatment. Therefore, the addition of HT and DNA-PKcsi to conventional radiotherapy is promising and might contribute to more efficient tumor control and patient outcome.


Assuntos
Neoplasias da Mama/terapia , Cromonas/farmacologia , Proteína Quinase Ativada por DNA/antagonistas & inibidores , Hipertermia Induzida , Morfolinas/farmacologia , Células-Tronco Neoplásicas/efeitos da radiação , Radiossensibilizantes/farmacologia , Neoplasias do Colo do Útero/terapia , Animais , Neoplasias da Mama/patologia , Quebras de DNA de Cadeia Dupla , Dano ao DNA , Reparo do DNA por Junção de Extremidades , Reparo do DNA , Feminino , Recombinação Homóloga , Humanos , Camundongos , Camundongos Nus , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Tolerância a Radiação , Radioterapia , Células Tumorais Cultivadas , Neoplasias do Colo do Útero/patologia
16.
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
17.
Curr Stem Cell Res Ther ; 11(5): 427-33, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26647913

RESUMO

Cancer stem cells (CSCs) are considered to be the origin of cancer and it is suggested that they are resistant to chemotherapy. Current therapies fail to eradicate CSCs and therefore selecting a resistant cell subset that is able to facilitate tumor recurrences. Betulinic acid (BetA) is a broad acting natural compound, shown to induce cell death via the inhibition of the stearoyl-CoA- desaturase (SCD- 1). This enzyme converts saturated fatty acids into unsaturated fatty acids and is over-expressed in tumor cells. Here we show that BetA induces rapid cell death in all colon CSCs tested and is able to affect the CSCs directly as shown, via the loss of clonogenic capacity. Similar results were observed with inhibition of SCD-1, suggesting that SCD-1 activity is indeed a vulnerable link in colon CSCs and can be considered an ideal target for therapy in colon cancer.


Assuntos
Neoplasias do Colo/patologia , Células-Tronco Neoplásicas/patologia , Triterpenos/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Células Clonais , Neoplasias do Colo/enzimologia , Neoplasias do Colo/genética , Inibidores Enzimáticos/farmacologia , Humanos , Mutação/genética , Células-Tronco Neoplásicas/efeitos dos fármacos , Triterpenos Pentacíclicos , Estearoil-CoA Dessaturase/antagonistas & inibidores , Estearoil-CoA Dessaturase/metabolismo
18.
Stem Cells ; 33(1): 35-44, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25186497

RESUMO

The cancer stem cell (CSC) model is describing tumors as a hierarchical organized system and CSCs are suggested to be responsible for cancer recurrence after therapy. The identification of specific markers of CSCs is therefore of paramount importance. Here, we show that high levels of lipid droplets (LDs) are a distinctive mark of CSCs in colorectal (CR) cancer. This increased lipid content was clearly revealed by label-free Raman spectroscopy and it directly correlates with well-accepted CR-CSC markers as CD133 and Wnt pathway activity. By xenotransplantation experiments, we have finally demonstrated that CR-CSCs overexpressing LDs retain most tumorigenic potential. A relevant conceptual advance in this work is the demonstration that a cellular organelle, the LD, is a signature of CSCs, in addition to molecular markers. A further functional characterization of LDs could lead soon to design new target therapies against CR-CSCs.


Assuntos
Neoplasias Colorretais/patologia , Células-Tronco Neoplásicas/patologia , Análise Espectral Raman/métodos , Animais , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/metabolismo , Humanos , Gotículas Lipídicas , Camundongos , Células-Tronco Neoplásicas/metabolismo , Via de Sinalização Wnt
19.
Semin Cancer Biol ; 23(6 Pt B): 522-32, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24012661

RESUMO

The mutual and interdependent interaction between tumor and its microenvironment is a crucial topic in cancer research. Recently, it was reported that targeting stromal events could improve efficacies of current therapeutics and prevent metastatic spreading. Tumor microenvironment is a "complex network" of different cell types, soluble factors, signaling molecules and extracellular matrix components, which orchestrate the fate of tumor progression. As by definition, cancer stem cells (CSCs) are proposed to be the unique cell type able to maintain tumor mass and survive outside the primary tumor at metastatic sites. Being exposed to environmental stressors, including reactive oxygen species (ROS), CSCs have developed a GSH-dependent antioxidant system to improve ROS defense capability and acquire a malignant phenotype. Nevertheless, tumor progression is dependent on extracellular matrix remodeling, fibroblasts and macrophages activation in response to oxidative stress, as well as epithelial mesenchymal transition (EMT)-inducing signals and endothelial and perivascular cells recruitment. Besides providing a survival advantage by inducing de novo angiogenesis, tumor-associated vessels contribute to successful dissemination by facilitating tumor cells entry into the circulatory system and driving the formation of pre-metastatic niche. In this review, we focus on the synergistic effect of hypoxia inducible factors (HIFs) and vascular endothelial growth factors (VEGFs) in the successful outgrowth of metastasis, integrating therefore many of the emerging models and theories in the field.


Assuntos
Neoplasias/metabolismo , Neoplasias/patologia , Microambiente Tumoral , Animais , Movimento Celular , Sobrevivência Celular , Transição Epitelial-Mesenquimal , Humanos , Hipóxia/metabolismo , Metástase Neoplásica , Neoplasias/terapia , Células-Tronco Neoplásicas/metabolismo , Neovascularização Patológica/metabolismo , Oxirredução , Transdução de Sinais , Nicho de Células-Tronco
20.
J Immunol ; 190(5): 2381-90, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23345327

RESUMO

Tumor cell populations have been recently proposed to be composed of two compartments: tumor-initiating cells characterized by a slow and asymmetrical growth, and the "differentiated" cancer cells with a fast and symmetrical growth. Cancer stem cells or cancer-initiating cells (CICs) play a crucial role in tumor recurrence. The resistance of CICs to drugs and irradiation often allows them to survive traditional therapy. NK cells are potent cytotoxic lymphocytes that can recognize tumor cells. In this study, we have analyzed the NK cell recognition of tumor target cells derived from the two cancer cell compartments of colon adenocarcinoma lesions. Our data demonstrate that freshly purified allogeneic NK cells can recognize and kill colorectal carcinoma-derived CICs whereas the non-CIC counterpart of the tumors (differentiated tumor cells), either autologous or allogeneic, is less susceptible to NK cells. This difference in the NK cell susceptibility correlates with higher expression on CICs of ligands for NKp30 and NKp44 in the natural cytotoxicity receptor (NCR) group of activating NK receptors. In contrast, CICs express lower levels of MHC class I, known to inhibit NK recognition, on their surface than do the "differentiated" tumor cells. These data have been validated by confocal microscopy where NCR ligands and MHC class I molecule membrane distribution have been analyzed. Moreover, NK cell receptor blockade in cytotoxicity assays demonstrates that NCRs play a major role in the recognition of CIC targets. This study strengthens the idea that biology-based therapy harnessing NK cells could be an attractive opportunity in solid tumors.


Assuntos
Adenocarcinoma/imunologia , Neoplasias do Colo/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Células Matadoras Naturais/imunologia , Receptor 2 Desencadeador da Citotoxicidade Natural/imunologia , Receptor 3 Desencadeador da Citotoxicidade Natural/imunologia , Células-Tronco Neoplásicas/imunologia , Adenocarcinoma/genética , Adenocarcinoma/patologia , Animais , Linhagem da Célula/imunologia , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Citotoxicidade Imunológica , Expressão Gênica , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Células Matadoras Naturais/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Microscopia Confocal , Receptor 2 Desencadeador da Citotoxicidade Natural/genética , Receptor 3 Desencadeador da Citotoxicidade Natural/genética , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/transplante , Especificidade de Órgãos , Células Tumorais Cultivadas
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