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1.
J Immunother Cancer ; 9(10)2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34663639

RESUMO

BACKGROUND: Breast cancer (BC) progression to metastatic disease is the leading cause of death in women worldwide. Metastasis is driven by cancer stem cells (CSCs) and signals from their microenvironment. Interleukin (IL) 30 promotes BC progression, and its expression correlates with disease recurrence and mortality. Whether it acts by regulating BCSCs is unknown and could have significant therapeutic implications. METHODS: Human (h) and murine (m) BCSCs were tested for their production of and response to IL30 by using flow cytometry, confocal microscopy, proliferation and sphere-formation assays, and PCR array. Immunocompetent mice were used to investigate the role of BCSC-derived IL30 on tumor development and host outcome. TCGA PanCancer and Oncomine databases provided gene expression data from 1084 and 75 hBC samples, respectively, and immunostaining unveiled the BCSC microenvironment. RESULTS: hBCSCs constitutively expressed IL30 as a membrane-anchored glycoprotein. Blocking IL30 hindered their proliferation and self-renewal efficiency, which were boosted by IL30 overexpression. IL30 regulation of immunity gene expression in human and murine BCSCs shared a significant induction of IL23 and CXCL10. Both immunoregulatory mediators stimulated BCSC proliferation and self-renewal, while their selective blockade dramatically hindered IL30-dependent BCSC proliferation and mammosphere formation. Orthotopic implantation of IL30-overexpressing mBCSCs, in syngeneic mice, gave rise to poorly differentiated and highly proliferating MYC+KLF4+LAG3+ tumors, which expressed CXCL10 and IL23, and were infiltrated by myeloid-derived cells, Foxp3+ T regulatory cells and NKp46+RORγt+ type 3 innate lymphoid cells, resulting in increased metastasis and reduced survival. In tumor tissues from patients with BC, expression of IL30 overlapped with that of CXCL10 and IL23, and ranked beyond the 95th percentile in a Triple-Negative enriched BC collection from the Oncomine Platform. CIBERSORTx highlighted a defective dendritic cell, CD4+ T and γδ T lymphocyte content and a prominent LAG3 expression in IL30high versus IL30low human BC samples from the TCGA PanCancer collection. CONCLUSIONS: Constitutive expression of membrane-bound IL30 regulates BCSC viability by juxtacrine signals and via second-level mediators, mainly CXCL10 and IL23. Their autocrine loops mediate much of the CSC growth factor activity of IL30, while their paracrine effect contributes to IL30 shaping of immune contexture. IL30-related immune subversion, which also emerged from computational analyses, strongly suggests that targeting IL30 can restrain the BCSC compartment and counteract BC progression.

2.
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.
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.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32982967

RESUMO

Thyroid tumors are extremely heterogeneous varying from almost benign tumors with good prognosis as papillary or follicular tumors, to the undifferentiated ones with severe prognosis. Recently, several models of thyroid carcinogenesis have been described, mostly hypothesizing a major role of the thyroid cancer stem cell (TCSC) population in both cancer initiation and metastasis formation. However, the cellular origin of TCSC is still incompletely understood. Here, we review the principal epigenetic mechanisms relevant to TCSC origin and maintenance in both well-differentiated and anaplastic thyroid tumors. Specifically, we describe the alterations in DNA methylation, histone modifiers, and microRNAs (miRNAs) involved in TCSC survival, focusing on the potential of targeting aberrant epigenetic modifications for developing novel therapeutic approaches. Moreover, we discuss the bidirectional relationship between TCSCs and immune cells. The cells of innate and adaptive response can promote the TCSC-driven tumorigenesis, and conversely, TCSCs may favor the expansion of immune cells with protumorigenic functions. Finally, we evaluate the role of the tumor microenvironment and the complex cross-talk of chemokines, hormones, and cytokines in regulating thyroid tumor initiation, progression, and therapy refractoriness. The re-education of the stromal cells can be an effective strategy to fight thyroid cancer. Dissecting the genetic and epigenetic landscape of TCSCs and their interactions with tumor microenvironment cells is urgently needed to select more appropriate treatment and improve the outcome of patients affected by advanced differentiated and undifferentiated thyroid cancers.


Assuntos
Metástase Neoplásica/patologia , Células-Tronco Neoplásicas/patologia , Neoplasias da Glândula Tireoide/patologia , Metilação de DNA , Histonas/genética , Histonas/metabolismo , Humanos , MicroRNAs/genética , Metástase Neoplásica/genética , Células-Tronco Neoplásicas/metabolismo , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Microambiente Tumoral
6.
Cancers (Basel) ; 12(6)2020 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-32486505

RESUMO

Although improvement in early diagnosis and treatment ameliorated life expectancy of cancer patients, metastatic disease still lacks effective therapeutic approaches. Resistance to anticancer therapies stems from the refractoriness of a subpopulation of cancer cells-termed cancer stem cells (CSCs)-which is endowed with tumor initiation and metastasis formation potential. CSCs are heterogeneous and diverge by phenotypic, functional and metabolic perspectives. Intrinsic as well as extrinsic stimuli dictated by the tumor microenvironment (TME)have critical roles in determining cell metabolic reprogramming from glycolytic toward an oxidative phenotype and vice versa, allowing cancer cells to thrive in adverse milieus. Crosstalk between cancer cells and the surrounding microenvironment occurs through the interchange of metabolites, miRNAs and exosomes that drive cancer cells metabolic adaptation. Herein, we identify the metabolic nodes of CSCs and discuss the latest advances in targeting metabolic demands of both CSCs and stromal cells with the scope of improving current therapies and preventing cancer progression.

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
9.
Cancer Immunol Res ; 7(5): 841-852, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30940644

RESUMO

Immune checkpoint blockade therapy has changed prognoses for many melanoma patients. However, immune responses that correlate with clinical progression of the disease are still poorly understood. To identify immune responses correlating with melanoma clinical evolution, we analyzed serum cytokines as well as circulating NK and T-cell subpopulations from melanoma patients. The patients' immune profiles suggested that melanoma progression leads to changes in peripheral blood NK and T-cell subsets. Stage IV melanoma was characterized by an increased frequency of CCR7+CD56bright NK cells as well as high serum concentrations of the CCR7 ligand CCL19. CCR7 expression and CCL19 secretion were also observed in melanoma cell lines. The CCR7+ melanoma cell subpopulation coexpressed PD-L1 and Galectin-9 and had stemness properties. Analysis of melanoma-derived cancer stem cells (CSC) showed high CCR7 expression; these CSCs were efficiently recognized and killed by NK cells. An accumulation of CCR7+, PD-L1+, and Galectin-9+ melanoma cells in melanoma metastases was demonstrated ex vivo Altogether, our data identify biomarkers that may mark a CCR7-driven metastatic melanoma pathway.


Assuntos
Células Matadoras Naturais/imunologia , Melanoma/imunologia , Antígeno B7-H1/imunologia , Linhagem Celular , Quimiocina CCL19/imunologia , Técnicas de Cocultura , Citocinas/sangue , Feminino , Galectinas/imunologia , Humanos , Masculino , Melanoma/sangue , Melanoma/patologia , Células-Tronco Neoplásicas/imunologia , Receptores CCR7/imunologia
10.
Front Cell Dev Biol ; 7: 16, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30834247

RESUMO

Notwithstanding cancer patients benefit from a plethora of therapeutic alternatives, drug resistance remains a critical hurdle. Indeed, the high mortality rate is associated with metastatic disease, which is mostly incurable due to the refractoriness of metastatic cells to current treatments. Increasing data demonstrate that tumors contain a small subpopulation of cancer stem cells (CSCs) able to establish primary tumor and metastasis. CSCs are endowed with multiple treatment resistance capabilities comprising a highly efficient DNA damage repair machinery, the activation of survival pathways, enhanced cellular plasticity, immune evasion and the adaptation to a hostile microenvironment. Due to the presence of distinct cell populations within a tumor, cancer research has to face the major challenge of targeting the intra-tumoral as well as inter-tumoral heterogeneity. Thus, targeting molecular drivers operating in CSCs, in combination with standard treatments, may improve cancer patients' outcomes, yielding long-lasting responses. Here, we report a comprehensive overview on the most significant therapeutic advances that have changed the known paradigms of cancer treatment with a particular emphasis on newly developed compounds that selectively affect the CSC population. Specifically, we are focusing on innovative therapeutic approaches including differentiation therapy, anti-angiogenic compounds, immunotherapy and inhibition of epigenetic enzymes and microenvironmental cues.

11.
Int J Cancer ; 144(2): 366-371, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30151914

RESUMO

Patient-derived xenograft (PDX) models have become an important asset in translational cancer research. However, to provide a robust preclinical platform, PDXs need to accommodate the tumor heterogeneity that is observed in patients. Colorectal cancer (CRC) can be stratified into four consensus molecular subtypes (CMS) with distinct biological and clinical features. Surprisingly, using a set of CRC patients, we revealed the partial representation of tumor heterogeneity in PDX models. The epithelial subtypes, the largest subgroups of CRC subtype, were very ineffective in establishing PDXs, indicating the need for further optimization to develop an effective personalized therapeutic approach to CRC. Moreover, we showed that tumor cell proliferation was associated with successful PDX establishment and able to distinguish patient with poor clinical outcomes within CMS2 group.


Assuntos
Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Xenoenxertos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Animais , Humanos , Camundongos
12.
BMC Cancer ; 18(1): 1176, 2018 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-30482160

RESUMO

BACKGROUND: It has been proposed that mesenchymal stromal cells (MSCs) promote tumor progression by interacting with tumor cells and other stroma cells in the complex network of the tumor microenvironment. We characterized MSCs isolated and expanded from tumor tissues of pediatric patients diagnosed with neuroblastomas (NB-MSCs) to define interactions with the tumor microenvironment. METHODS: Specimens were obtained from 7 pediatric patients diagnosed with neuroblastoma (NB). Morphology, immunophenotype, differentiation capacity, proliferative growth, expression of stemness and neural differentiation markers were evaluated. Moreover, the ability of cells to modulate the immune response, i.e. inhibition of phytohemagglutinin (PHA) activated peripheral blood mononuclear cells (PBMCs) and natural killer (NK) cytotoxic function, was examined. Gene expression profiles, known to be related to tumor cell stemness, Wnt pathway activation, epithelial-mesenchymal transition (EMT) and tumor metastasis were also evaluated. Healthy donor bone marrow-derived MSCs (BM-MSC) were employed as controls. RESULTS: NB-MSCs presented the typical MSC morphology and phenotype. They showed a proliferative capacity superimposable to BM-MSCs. Stemness marker expression (Sox2, Nanog, Oct3/4) was comparable to BM-MSCs. NB-MSC in vitro osteogenic and chondrogenic differentiation was similar to BM-MSCs, but NB-MSCs lacked adipogenic differentiation capacity. NB-MSCs reached senescence phases at a median passage of P7 (range, P5-P13). NB-MSCs exhibited greater immunosuppressive capacity on activated T lymphocytes at a 1:2 (MSC: PBMC) ratio compared with BM-MSCs (p = 0.018). NK cytotoxic activity was not influenced by co-culture, either with BM-MSCs or NB-MSCs. Flow-cytometry cell cycle analysis showed that NB-MSCs had an increased number of cells in the G0-G1 phase compared to BM-MSCs. Transcriptomic profiling results indicated that NB-MSCs were enriched with EMT genes compared to BM-MSCs. CONCLUSIONS: We characterized the biological features, the immunomodulatory capacity and the gene expression profile of NB-MSCs. The NB-MSC gene expression profile and their functional properties suggest a potential role in promoting tumor escape, invasiveness and metastatic traits of NB cancer cells. A better understanding of the complex mechanisms underlying the interactions between NB cells and NB-derived MSCs should shed new light on potential novel therapeutic approaches.


Assuntos
Fibroblastos Associados a Câncer/metabolismo , Células-Tronco Mesenquimais/metabolismo , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Microambiente Tumoral , Biomarcadores Tumorais , Células da Medula Óssea/metabolismo , Fibroblastos Associados a Câncer/patologia , Ciclo Celular , Diferenciação Celular/genética , Separação Celular/métodos , Células Cultivadas , Pré-Escolar , Técnicas de Cocultura , Feminino , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Imunofenotipagem/métodos , Lactente , Masculino , Mutação , Neuroblastoma/epidemiologia , Neuroblastoma/terapia , Vigilância da População , Sistema de Registros , Transdução de Sinais , Microambiente Tumoral/genética
13.
Nat Commun ; 9(1): 3921, 2018 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-30237396

RESUMO

The original version of this Article contained an error in the spelling of the author Miriam Gaggianesi, which was incorrectly given as Miriam Giaggianesi. Furthermore, the affiliation details for Gabriella Gaudioso, Valentina Vaira, and Silvano Bosari incorrectly omitted 'Division of Pathology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, 20122, Italy'. Finally, the affiliation details for Alice Turdo, Miriam Gaggianesi, Aurora Chinnici and Elisa Lipari were incorrectly given as 'Dipartimento di Biotecnologie Mediche e Medicina Legale Sezione di Biochimica Medica, Facoltà di Medicina e Chirurgia, Policlinico "P.Giaccone", Università di Palermo, Palermo, 90127, Italy'. The correct affiliation is 'Department of Surgical, Oncological and Stomatological Sciences, University of Palermo, Palermo, 90127, Italy'. These errors have now been corrected in both the PDF and HTML versions of the Article.

14.
Cell Death Dis ; 9(8): 821, 2018 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-30050081

RESUMO

Mir-205 plays an important role in epithelial biogenesis and in mammary gland development but its role in cancer still remains controversial depending on the specific cellular context and target genes. We have previously reported that miR-205-5p is upregulated in breast cancer stem cells targeting ERBB pathway and leading to targeted therapy resistance. Here we show that miR-205-5p regulates tumorigenic properties of breast cancer cells, as well as epithelial to mesenchymal transition. Silencing this miRNA in breast cancer results in reduced tumor growth and metastatic spreading in mouse models. Moreover, we show that miR-205-5p knock-down can be obtained with the use of specific locked nucleic acids oligonucleotides in vivo suggesting a future potential use of this approach in therapy.


Assuntos
MicroRNAs/metabolismo , Oligonucleotídeos/metabolismo , Animais , Antagomirs/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Metástase Neoplásica , Transplante Heterólogo
15.
Nat Commun ; 9(1): 1024, 2018 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-29523784

RESUMO

Breast cancer consists of highly heterogeneous tumors, whose cell of origin and driver oncogenes are difficult to be uniquely defined. Here we report that MYC acts as tumor reprogramming factor in mammary epithelial cells by inducing an alternative epigenetic program, which triggers loss of cell identity and activation of oncogenic pathways. Overexpression of MYC induces transcriptional repression of lineage-specifying transcription factors, causing decommissioning of luminal-specific enhancers. MYC-driven dedifferentiation supports the onset of a stem cell-like state by inducing the activation of de novo enhancers, which drive the transcriptional activation of oncogenic pathways. Furthermore, we demonstrate that the MYC-driven epigenetic reprogramming favors the formation and maintenance of tumor-initiating cells endowed with metastatic capacity. This study supports the notion that MYC-driven tumor initiation relies on cell reprogramming, which is mediated by the activation of MYC-dependent oncogenic enhancers, thus establishing a therapeutic rational for treating basal-like breast cancers.


Assuntos
Neoplasias da Mama/metabolismo , Epigênese Genética , Células-Tronco Neoplásicas/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/fisiopatologia , Carcinogênese , Linhagem Celular Tumoral , Reprogramação Celular , Elementos Facilitadores Genéticos , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos SCID , Células-Tronco Neoplásicas/citologia
16.
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.

17.
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
18.
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
19.
Sci Rep ; 7: 43013, 2017 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-28220839

RESUMO

Combined MAPK/PI3K pathway inhibition represents an attractive, albeit toxic, therapeutic strategy in oncology. Since PTEN lies at the intersection of these two pathways, we investigated whether PTEN status determines the functional response to combined pathway inhibition. PTEN (gene, mRNA, and protein) status was extensively characterized in a panel of cancer cell lines and combined MEK/mTOR inhibition displayed highly synergistic pharmacologic interactions almost exclusively in PTEN-loss models. Genetic manipulation of PTEN status confirmed a mechanistic role for PTEN in determining the functional outcome of combined pathway blockade. Proteomic analysis showed greater phosphoproteomic profile modification(s) in response to combined MEK/mTOR inhibition in PTEN-loss contexts and identified JAK1/STAT3 activation as a potential mediator of synergistic interactions. Overall, our results show that PTEN-loss is a crucial determinant of synergistic interactions between MAPK and PI3K pathway inhibitors, potentially exploitable for the selection of cancer patients at the highest chance of benefit from combined therapeutic strategies.


Assuntos
MAP Quinase Quinase Quinases/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Linhagem Celular Tumoral , Sinergismo Farmacológico , Everolimo/farmacologia , Feminino , Humanos , Janus Quinase 1/genética , Janus Quinase 1/metabolismo , MAP Quinase Quinase Quinases/antagonistas & inibidores , Camundongos , Camundongos Nus , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , PTEN Fosfo-Hidrolase/antagonistas & inibidores , PTEN Fosfo-Hidrolase/genética , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Piridonas/farmacologia , Pirimidinonas/farmacologia , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Serina-Treonina Quinases TOR/antagonistas & inibidores
20.
Oncotarget ; 8(12): 19507-19521, 2017 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-28061479

RESUMO

Breast cancer remains one of the leading causes of cancer mortality among women. It has been proved that the onset of cancer depends on a very small pool of tumor cells with a phenotype similar to that of normal adult stem cells. Cancer stem cells (CSC) possess self-renewal and multilineage differentiation potential as well as a robust ability to sustain tumorigenesis. Evidence suggests that CSCs contribute to chemotherapy resistance and to survival under hypoxic conditions. Interestingly, hypoxia in turn regulates self-renewal in CSCs and these effects may be primarily mediated by hypoxic inducible factors (HIFs). Recently, microRNAs (miRNAs) have emerged as critical players in the maintenance of pluripotency and self-renewal in normal and cancer stem cells. Here, we demonstrate that miR-24 is upregulated in breast CSCs and that its overexpression increases the number of mammospheres and the expression of stem cell markers. MiR-24 also induces apoptosis resistance through the regulation of BimL expression. Moreover, we identify a new miR-24 target, FIH1, which promotes HIFα degradation: miR-24 increases under hypoxic conditions, causing downregulation of FIH1 and upregulation of HIF1α. In conclusion, miR-24 hampers chemotherapy-induced apoptosis in breast CSCs and increases cell resistance to hypoxic conditions through an FIH1-HIFα pathway.


Assuntos
Neoplasias da Mama/patologia , Hipóxia Celular/genética , Autorrenovação Celular/genética , Resistencia a Medicamentos Antineoplásicos/genética , Oxigenases de Função Mista/metabolismo , Células-Tronco Neoplásicas/patologia , Proteínas Repressoras/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cisplatino/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , MicroRNAs/genética , Oxigenases de Função Mista/genética , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Proteínas Repressoras/genética , Células Tumorais Cultivadas
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