RESUMO
The incidence of keratinocyte cancer (basal cell and squamous cell carcinomas of the skin) is 17-fold lower in Singapore than the UK1-3, despite Singapore receiving 2-3 times more ultraviolet (UV) radiation4,5. Aging skin contains somatic mutant clones from which such cancers develop6,7. We hypothesized that differences in keratinocyte cancer incidence may be reflected in the normal skin mutational landscape. Here we show that, compared to Singapore, aging facial skin from populations in the UK has a fourfold greater mutational burden, a predominant UV mutational signature, increased copy number aberrations and increased mutant TP53 selection. These features are shared by keratinocyte cancers from high-incidence and low-incidence populations8-13. In Singaporean skin, most mutations result from cell-intrinsic processes; mutant NOTCH1 and NOTCH2 are more strongly selected than in the UK. Aging skin in a high-incidence country has multiple features convergent with cancer that are not found in a low-risk country. These differences may reflect germline variation in UV-protective genes.
Assuntos
Carcinoma de Células Escamosas , Neoplasias Cutâneas , Humanos , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Carcinoma de Células Escamosas/genética , Queratinócitos , Raios Ultravioleta/efeitos adversos , MutaçãoRESUMO
Resection of infiltrated tumor-draining lymph nodes (TDLNs) is a standard practice for the treatment of several cancers including breast cancer and melanoma. However, many randomized prospective trials have failed to show convincing clinical benefits associated with LN removal and the role of TDLNs in cancer dissemination is poorly understood. Here, we found in a well-characterized spontaneous mouse model of uveal melanoma that the growth of the primary tumor was accompanied by increased lymphangiogenesis and cancer cell colonization in the LNs draining the eyes. But, unexpectedly, early resection of the TDLNs increased the growth of the primary tumor and associated blood vessels as well as promoted cancer cell survival and dissemination. These effects were accompanied by increased tumor cell proliferation and expression of phosphorylated AKT. Topical application of a broad anti-inflammatory agent, Tobradex, or an oral treatment with cyclooxygenase-2 specific inhibitor, Celecoxib, reversed tumor progression observed after complete lymphadenectomy. Our study confirms the importance of tumor homeostasis in cancer progression by showing the enhancing effects of TDLN removal on tumor growth and cancer cell dissemination, and suggests that TDLN resection may only be beneficial if used in combination with anti-inflammatory drugs such as Tobradex and Celecoxib.
Assuntos
Movimento Celular , Proliferação de Células , Excisão de Linfonodo/efeitos adversos , Melanoma/cirurgia , Neoplasias Experimentais/cirurgia , Neoplasias Uveais/cirurgia , Animais , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase 2/farmacologia , Progressão da Doença , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Melanoma/genética , Melanoma/metabolismo , Melanoma/secundário , Camundongos , Camundongos Transgênicos , Neoplasias Experimentais/genética , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Neovascularização Patológica , Fenótipo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-ret/genética , Fatores de Tempo , Carga Tumoral , Neoplasias Uveais/genética , Neoplasias Uveais/metabolismo , Neoplasias Uveais/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismoRESUMO
Hepatocellular carcinoma (HCC) is associated with high mortality and the current therapy for advanced HCC, Sorafenib, offers limited survival benefits. Here we assessed whether combining the TLR3 agonist: lysine-stabilized polyinosinic-polycytidylic-acid (poly-ICLC) with Sorafenib could enhance tumor control in HCC. Combinatorial therapy with poly-ICLC and Sorafenib increased apoptosis and reduced proliferation of HCC cell lines in vitro, in association with impaired phosphorylation of AKT, MEK and ERK. In vivo, the combinatorial treatment enhanced control of tumor growth in two mouse models: one transplanted with Hepa 1-6 cells, and the other with liver tumors induced using the Sleeping beauty transposon. Tumor cell apoptosis and host immune responses in the tumor microenvironment were enhanced. Particularly, the activation of local NK cells, T cells, macrophages and dendritic cells was enhanced. Decreased expression of the inhibitory signaling molecules PD-1 and PD-L1 was observed in tumor-infiltrating CD8+ T cells and tumor cells, respectively. Tumor infiltration by monocytic-myeloid derived suppressor cells (Mo-MDSC) was also reduced indicating the reversion of the immunosuppressive tumor microenvironment. Our data demonstrated that the combinatorial therapy with poly-ICLC and Sorafenib enhances tumor control and local immune response hence providing a rationale for future clinical studies.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboximetilcelulose Sódica/análogos & derivados , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Niacinamida/análogos & derivados , Compostos de Fenilureia/administração & dosagem , Poli I-C/química , Polilisina/análogos & derivados , Receptor 3 Toll-Like/agonistas , Animais , Apoptose , Linfócitos T CD8-Positivos/citologia , Carboximetilcelulose Sódica/química , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Progressão da Doença , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Sistema Imunitário , Imunossupressores/química , MAP Quinase Quinase Quinases/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos SCID , Niacinamida/administração & dosagem , Niacinamida/química , Compostos de Fenilureia/química , Fosforilação , Polilisina/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , SorafenibeRESUMO
The infiltration of T lymphocytes within tumors is associated with better outcomes in cancer patients, yet current understanding of factors that influence T-lymphocyte infiltration into tumors remains incomplete. In our study, Temozolomide (TMZ), a chemotherapeutic drug used to treat metastatic melanoma, induced T-cell infiltration into transplanted melanoma and into genitourinary (GU) tumors in mice developing spontaneous melanoma. In contrast, TMZ treatment did not increase T-cell infiltration into cutaneous tumors, despite similar increases in the expression of the (C-X-C) chemokines CXCL9 and CXCL10 in all sites after TMZ exposure. Our findings reveal that the matrix architecture of the GU tumor stroma, and its ability to present CXCL9 and CXCL10 after TMZ treatment played a key role in favouring T-cell infiltration. We subsequently demonstrate that modifications of these key elements by combined collagenase and TMZ treatment induced T-cell infiltration into skin tumors. T cells accumulating within GU tumors after TMZ treatment exhibited T helper type-1 effector and cytolytic functional phenotypes, which are important for control of tumor growth. Our findings highlight the importance of the interaction between tumor stroma and chemokines in influencing T-cell migration into tumors, thereby impacting immune control of tumor growth. This knowledge will aid the development of strategies to promote T-cell infiltration into cancerous lesions and has the potential to markedly improve treatment outcomes.
Assuntos
Imunoterapia/métodos , Macrófagos/imunologia , Melanoma/terapia , Evasão Tumoral , Microambiente Tumoral , Neoplasias Uveais/terapia , Animais , Comunicação Celular , Humanos , Macrófagos/metabolismo , Melanoma/imunologia , Melanoma/metabolismo , Melanoma/patologia , Fenótipo , Transdução de Sinais , Neoplasias Uveais/imunologia , Neoplasias Uveais/metabolismo , Neoplasias Uveais/patologiaRESUMO
Surgical resection of tumors is often followed by regrowth at the primary site and metastases may emerge rapidly following removal of the primary tumor. Macrophages are important drivers of tumor growth, and here we investigated their involvement in postoperative relapse as well as explore macrophage depletion as an adjuvant to surgical resection. RETAAD mice develop spontaneous metastatic melanoma that begins in the eye. Removal of the eyes as early as 1 week of age did not prevent the development of metastases; rather, surgery led to increased proliferation of tumor cells locally and in distant metastases. Surgery-induced increase in tumor cell proliferation correlated with increased macrophage density within the tumor. Moreover, macrophages stimulate tumor sphere formation from tumor cells of post-surgical but not control mice. Macrophage depletion with a diet containing the CSF-1R specific kinase inhibitor Ki20227 following surgery significantly reduced postoperative tumor recurrence and abrogated enhanced metastatic outgrowth. Our results confirm that tumor cells disseminate early, and show that macrophages contribute both to post-surgical tumor relapse and growth of metastases, likely through stimulating a population of tumor-initiating cells. Thus macrophage depletion warrants exploration as an adjuvant to surgical resection.
Assuntos
Macrófagos/patologia , Melanoma Experimental/patologia , Melanoma Experimental/cirurgia , Animais , Processos de Crescimento Celular/fisiologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Humanos , Macrófagos/metabolismo , Masculino , Melanoma Experimental/metabolismo , Camundongos , Camundongos Transgênicos , Recidiva Local de Neoplasia/prevenção & controle , Proteínas Proto-Oncogênicas c-ret/genética , Procedimentos Cirúrgicos Operatórios/métodosRESUMO
M2 macrophages promote tumor growth and metastasis, but their interactions with specific tumor cell populations are poorly characterized. Using a mouse model of spontaneous melanoma, we showed that CD34- but not CD34+ tumor-initiating cells (TICs) depend on M2 macrophages for survival and proliferation. Tumor-associated macrophages (TAMs) and macrophage-conditioned media protected CD34- TICs from chemotherapy in vitro. In vivo, while inhibition of CD115 suppressed the macrophage-dependent CD34- TIC population, chemotherapy accelerated its development. The ability of TICs to respond to TAMs was acquired during melanoma progression and immediately preceded a surge in metastatic outgrowth. TAM-derived transforming growth factor-ß (TGFß) and polyamines produced via the Arginase pathway were critical for stimulation of TICs and synergized to promote their growth.
Assuntos
Arginase/metabolismo , Macrófagos/imunologia , Melanoma/imunologia , Melanoma/metabolismo , Células-Tronco Neoplásicas/imunologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Proliferação de Células/fisiologia , Sobrevivência Celular/fisiologia , Modelos Animais de Doenças , Feminino , Masculino , Melanoma/patologia , Camundongos , Camundongos Mutantes , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Transdução de Sinais/imunologiaRESUMO
The immune system has multiple, complex, and sometimes opposing roles during cancer progression. While immune-compromised individuals have a higher incidence of cancers, inflammation is also associated with increased risk of disease progression. It is becoming apparent that simple measures of immune responses in the blood are of limited use in cancer. Instead, the importance of the exact identity and functional characteristics of tumor-infiltrating immune cells is increasingly recognized. This realization has led to recent studies that have revealed a critical role for chemokine expression in the tumor microenvironment and suggested a therapeutic potential of manipulating intratumoral expression of chemokines to alter the local immune milieu.
Assuntos
Biomarcadores Tumorais/imunologia , Quimiocinas/imunologia , Neoplasias/diagnóstico , Neoplasias/imunologia , Animais , Movimento Celular/imunologia , Modelos Animais de Doenças , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Imunidade , Vigilância Imunológica , Camundongos , Camundongos Transgênicos , Neoplasias/genética , Prognóstico , Microambiente TumoralRESUMO
Neural stem cells (NSCs) are self-renewing multipotent cells that undergo symmetric and asymmetric cell division during development of the nervous system. The behavior of NSCs is tightly regulated by intrinsic processes such as transcriptional and post-transcriptional control, as well as the stem cell niche factors that activate ligand-receptor-mediated signaling pathways. However, the role of these niche factors that regulate NSC behavior is not clearly understood. We identified chondroitin sulfate proteoglycan, apolipoprotein E (ApoE) and cystatin C as factors derived from the mouse neurosphere conditioned medium. Here, we show that ApoE is an autocrine/paracrine factor that regulates NSC survival. Stimulation of NSC survival is mediated by ApoE receptor interaction and the downstream extracellular signal-regulated kinase/mitogen-activated protein kinase signaling pathway. In addition, ApoE also enhanced neurosphere formation of mouse embryonic stem cell-derived NSCs. Finally, in vitro differentiation studies with ApoE knock-out NSCs suggest a role for ApoE in oligodendrogenesis.
Assuntos
Apolipoproteínas E/farmacologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Transdução de Sinais/fisiologia , Animais , Apolipoproteínas E/deficiência , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Embrião de Mamíferos , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Humanos , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oligodendroglia/fisiologia , Prosencéfalo/citologia , Ligação Proteica/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacosRESUMO
Understanding how autocrine/paracrine factors regulate neural stem cell (NSC) survival and growth is fundamental to the utilization of these cells for therapeutic applications and as cellular models for the brain. In vitro, NSCs can be propagated along with neural progenitors (NPs) as neurospheres (nsphs). The nsph conditioned medium (nsph-CM) contains cell-secreted factors that can regulate NSC behavior. However, the identity and exact function of these factors within the nsph-CM has remained elusive. We analyzed the nsph-CM by mass spectrometry and identified DSD-1-proteoglycan, a chondroitin sulfate proteoglycan (CSPG), apolipoprotein E (ApoE) and cystatin C as components of the nsph-CM. Using clonal assays we show that CSPG and ApoE are responsible for the ability of the nsph-CM to stimulate nsph formation whereas cystatin C is not involved. Clonal nsphs generated in the presence of CSPG show more than four-fold increase in NSCs. Thus CSPG specifically enhances the survival of NSCs. CSPG also stimulates the survival of embryonic stem cell (ESC)-derived NSCs, and thus may be involved in the developmental transition of ESCs to NSCs. In addition to its role in NSC survival, CSPG maintains the three dimensional structure of nsphs. Lastly, CSPG's effects on NSC survival may be mediated by enhanced signaling via EGFR, JAK/STAT3 and PI3K/Akt pathways.
Assuntos
Proteoglicanas de Sulfatos de Condroitina/metabolismo , Receptores ErbB/metabolismo , Neurônios/citologia , Células-Tronco/citologia , Animais , Apolipoproteínas E/metabolismo , Proliferação de Células , Sobrevivência Celular , Meios de Cultivo Condicionados/farmacologia , Cistatina C/metabolismo , Células-Tronco Embrionárias/citologia , Imuno-Histoquímica/métodos , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/citologia , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de SinaisRESUMO
Neuregulins (NRG) play important roles in the development, maintenance, and repair of the nervous system, with influences on neuronal migration, synaptogenesis, receptor subunit composition, and the proliferation/survival of oligodendrocytes and Schwann cells. However, the precise detail of how the NRGs signal through ErbB receptors, particularly at central synapses, is incomplete. The receptor kinase domain provides sites for association with adaptor proteins. In addition, evidence from recent reports suggests that ErbB2/4 receptors, through their C-terminal amino acids, can form specific associations with scaffolding proteins. The existence of such assemblies expands the range of signaling cascades available to the NRGs.