RESUMEN
Therapeutic failures in cancer therapy are often associated with metabolic plasticity. The use of metabolic modulators as anti-cancer agents has been effective in correcting metabolic alterations; however, molecular events behind metabolic switch are still largely unexplored. Herein, we characterize the molecular and functional events that follow prolonged oxidative phosphorylation inhibition by phenformin in order to study how melanoma cells adapt to this specific metabolic pressure. We show that melanoma cells cultured up to 3 months with high doses of phenformin (R-cells) are less viable and migrate and invade less than parental (S-) cells. Microarray analysis of R-melanoma cells reveals a switch in the energy production strategy accompanied by the modulation of several immunological-associated genes. R-cells display low oxygen consumption rate and high basal extracellular acidification rate. When treated with vemurafenib, R-cell viability, growth and extracellular signal-regulated kinase activation decrease. Finally, phenformin withdrawal reverts R-cells phenotype. In summary, our study provides an in vitro model of on-off metabolic switch in melanoma and reveals interesting molecular signatures controlling metabolic reprogramming in this tumour.
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Reprogramación Celular/inmunología , Hipoglucemiantes/uso terapéutico , Melanoma/genética , Fenformina/uso terapéutico , Humanos , Hipoglucemiantes/farmacología , Fenformina/farmacologíaRESUMEN
BACKGROUND: Chronic, degenerative diseases are often characterized by inflammation and aberrant angiogenesis. For these pathologies, including rheumatoid arthritis, cardiovascular and autoimmune diseases, cancer, diabetes, and obesity, current therapies have limited efficacy. OBJECTIVES: The validation of novel (chemo)preventive and interceptive approaches, and the use of new or repurposed agents, alone or in combination with registered drugs, are urgently required. RESULTS: Phytochemicals (triterpenoids, flavonoids, retinoids) and their derivatives, nonsteroidal anti-inflammatory drugs (aspirin) as well as biguanides (metformin and phenformin) originally developed from phytochemical backbones, are multi-target agents showing antiangiogenic and anti-anti-inflammatory proprieties. Many of them target AMPK and metabolic pathways such as the mTOR axis. We summarize the beneficial effects of several compounds in conferring protection and supporting therapy, and as a paradigm, we present data on terpenoids & biquanides on beer hop xanthohumol and hydroxytryrosol from olive mill waste waters. CONCLUSIONS: These molecules could be employed for combinatorial chemoprevention and interception approaches or chemoprevention/therapy regimens for cancer and other chronic complex diseases.
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Suplementos Dietéticos , Reposicionamiento de Medicamentos , Neoplasias/tratamiento farmacológico , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedad Crónica , HumanosRESUMEN
This corrects the article DOI: 10.1038/ncomms14797.
RESUMEN
Deregulation of autophagy is proposed to play a key pathogenic role in hepatocellular carcinoma (HCC), the most common primary malignancy of the liver and the third leading cause of cancer death. Autophagy is an evolutionarily conserved catabolic process activated to degrade and recycle cell's components. Under stress conditions, such as oxidative stress and nutrient deprivation, autophagy is an essential survival pathway that operates in harmony with other stress response pathways. These include the redox-sensitive transcription complex Nrf2-Keap1 that controls groups of genes with roles in detoxification and antioxidant processes, intermediary metabolism, and cell cycle regulation. Recently, a functional association between a dysfunctional autophagy and Nrf2 pathway activation has been identified in HCC. This appears to occur through the physical interaction of the autophagy adaptor p62 with the Nrf2 inhibitor Keap1, thus leading to increased stabilization and transcriptional activity of Nrf2, a key event in reprogramming metabolic and stress response pathways of proliferating hepatocarcinoma cells. These emerging molecular mechanisms and the therapeutic perspective of targeting Nrf2-p62 interaction in HCC are discussed in this paper along with the prognostic value of autophagy in this type of cancer.
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Autofagia/fisiología , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Factor 2 Relacionado con NF-E2/fisiología , Estrés Oxidativo , Proteínas de Unión al ARN/fisiología , Animales , Carcinoma Hepatocelular/etiología , Cloroquina/farmacología , Humanos , Hidroxicloroquina/farmacología , Neoplasias Hepáticas/etiologíaRESUMEN
The docking protein p140Cap negatively regulates tumour cell features. Its relevance on breast cancer patient survival, as well as its ability to counteract relevant cancer signalling pathways, are not fully understood. Here we report that in patients with ERBB2-amplified breast cancer, a p140Cap-positive status associates with a significantly lower probability of developing a distant event, and a clear difference in survival. p140Cap dampens ERBB2-positive tumour cell progression, impairing tumour onset and growth in the NeuT mouse model, and counteracting epithelial mesenchymal transition, resulting in decreased metastasis formation. One major mechanism is the ability of p140Cap to interfere with ERBB2-dependent activation of Rac GTPase-controlled circuitries. Our findings point to a specific role of p140Cap in curbing the aggressiveness of ERBB2-amplified breast cancers and suggest that, due to its ability to impinge on specific molecular pathways, p140Cap may represent a predictive biomarker of response to targeted anti-ERBB2 therapies.
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Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Neoplasias de la Mama/metabolismo , Receptor ErbB-2/metabolismo , Proteínas de Unión al GTP rac/metabolismo , Proteínas Adaptadoras del Transporte Vesicular/genética , Animales , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Progresión de la Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones Endogámicos BALB C , Ratones Transgénicos , Metástasis de la Neoplasia , Neoplasias Experimentales/genética , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología , Receptor ErbB-2/genética , Proteínas de Unión al GTP rac/genéticaRESUMEN
Melanoma is the most dangerous and treatment-resistant skin cancer. Tumor resistance and recurrence are due to the persistence in the patient of aggressive cells with stem cell features, the cancer stem cells (CSC). Recent evidences have shown that CSC display a distinct metabolic profile as compared to tumor bulk population: a promising anti-tumor strategy is therefore to target specific metabolic pathways driving CSC behavior. Biguanides (metformin and phenformin) are anti-diabetic drugs able to perturb cellular metabolism and displaying anti-cancer activity. However, their ability to target the CSC compartment in melanoma is not known. Here we show that phenformin, but not metformin, strongly reduces melanoma cell viability, growth and invasion in both 2D and 3D (spheroids) models. While phenformin decreases melanoma CSC markers expression and the levels of the pro-survival factor MITF, MITF overexpression fails to prevent phenformin effects. Phenformin significantly reduces cell viability in melanoma by targeting both CSC (ALDHhigh) and non-CSC cells and by significantly reducing the number of viable cells in ALDHhigh and ALDHlow-derived spheroids. Consistently, phenformin reduces melanoma cell viability and growth independently from SOX2 levels. Our results show that phenformin is able to affect both CSC and non-CSC melanoma cell viability and growth and suggests its potential use as anti-cancer therapy in melanoma.
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Metabolismo Energético/efectos de los fármacos , Melanoma/tratamiento farmacológico , Células Madre Neoplásicas/efectos de los fármacos , Fenformina/farmacología , Neoplasias Cutáneas/tratamiento farmacológico , Aldehído Deshidrogenasa/metabolismo , Antineoplásicos/farmacología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Regulación Neoplásica de la Expresión Génica , Humanos , Melanoma/genética , Melanoma/metabolismo , Melanoma/patología , Metformina/farmacología , Factor de Transcripción Asociado a Microftalmía/genética , Factor de Transcripción Asociado a Microftalmía/metabolismo , Invasividad Neoplásica , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Fenotipo , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología , Esferoides Celulares , Factores de Tiempo , TransfecciónRESUMEN
Angiogenesis, a process characterized by the formation of new blood vessels from pre-existing ones, is a crucial step in tumor growth and dissemination. Recently, increased attention has been addressed to the ability of flavonoids to prevent cancer by suppressing angiogenesis, strategy that we named "angioprevention". Several natural compounds exert their anti-tumor properties by activating 5' adenosine monophosphate-activated protein kinase (AMPK), a key regulator of metabolism in cancer cells. Drugs with angiopreventive activities, in particular metformin, regulate AMPK in endothelial cells. Here we investigated the involvement of AMPK in the anti-angiogenic effects of xanthohumol (XN), the major prenylated flavonoid of the hop plant, and mechanisms of action. The anti-angiogenic activity of XN was more potent than epigallocatechin-3-gallate (EGCG). Treatment of endothelial cells with XN led to increased AMPK phosphorylation and activity. Functional studies using biochemical approaches confirmed that AMPK mediates XN anti-angiogenic activity. AMPK activation by XN was mediated by CAMMKß, but not LKB1. Analysis of the downstream mechanisms showed that XN-induced AMPK activation reduced nitric oxide (NO) levels in endothelial cells by decreasing eNOS phosphorylation. Finally, AKT pathway was inactivated by XN as part of its anti-angiogenic activity, but independently from AMPK, suggesting that these two signaling pathways proceed autonomously. Our study dissects the molecular mechanism by which XN exerts its potent anti-angiogenic activity, pointing out AMPK as a crucial signal transducer.
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Inhibidores de la Angiogénesis/farmacología , Endotelio Vascular/fisiología , Flavonoides/farmacología , Humulus , Neoplasias/tratamiento farmacológico , Neovascularización Patológica/tratamiento farmacológico , Propiofenonas/farmacología , Proteínas Quinasas/metabolismo , Quinasas de la Proteína-Quinasa Activada por el AMP , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Endotelio Vascular/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana , Humanos , Óxido Nítrico Sintasa de Tipo III/metabolismo , Fosforilación , Prenilación , Transducción de SeñalRESUMEN
Metformin can induce breast cancer (BC) cell apoptosis and reduce BC local and metastatic growth in preclinical models. Since Metformin is frequently used along with Aspirin or beta-blockers, we investigated the effect of Metformin, Aspirin and the beta-blocker Atenolol in several BC models. In vitro, Aspirin synergized with Metformin in inducing apoptosis of triple negative and endocrine-sensitive BC cells, and in activating AMPK in BC and in white adipose tissue (WAT) progenitors known to cooperate to BC progression. Both Aspirin and Atenolol added to the inhibitory effect of Metformin against complex I of the respiratory chain. In both immune-deficient and immune-competent preclinical models, Atenolol increased Metformin activity against angiogenesis, local and metastatic growth of HER2+ and triple negative BC. Aspirin increased the activity of Metformin only in immune-competent HER2+ BC models. Both Aspirin and Atenolol, when added to Metformin, significantly reduced the endothelial cell component of tumor vessels, whereas pericytes were reduced by the addition of Atenolol but not by the addition of Aspirin. Our data indicate that the addition of Aspirin or of Atenolol to Metformin might be beneficial for BC control, and that this activity is likely due to effects on both BC and microenvironment cells.
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Antineoplásicos/farmacología , Aspirina/farmacología , Atenolol/farmacología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Metformina/farmacología , Microambiente Tumoral/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/metabolismo , Tejido Adiposo Blanco/efectos de los fármacos , Tejido Adiposo Blanco/metabolismo , Animales , Apoptosis/efectos de los fármacos , Biomarcadores de Tumor , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Modelos Animales de Enfermedad , Sinergismo Farmacológico , Complejo I de Transporte de Electrón/metabolismo , Femenino , Humanos , NAD/metabolismo , Metástasis de la Neoplasia , Células Madre/efectos de los fármacos , Células Madre/metabolismo , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/metabolismo , Neoplasias de la Mama Triple Negativas/patología , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Squamous Cell Carcinoma-derived Stem-like Cells (SCC-SC) originate from alterations in keratinocyte stem cells (KSC) gene expression and sustain tumor development, invasion and recurrence. Since survivin, a KSC marker, is highly expressed in SCC-SC, we evaluate its role in SCC-SC cell growth and SCC models. Survivin silencing by siRNA decreases clonal growth of SCC keratinocytes and viability of total, rapidly adhering (RAD) and non-RAD (NRAD) cells from primary SCC. Similarly, survivin silencing reduces the expression of stem cell markers (OCT4, NOTCH1, CD133, ß1-integrin), while it increases the level of differentiation markers (K10, involucrin). Moreover, survivin silencing improves the malignant phenotype of SCC 3D-reconstruct, as demonstrated by reduced epidermal thickness, lower Ki-67 positive cell number, and decreased expression of MMP9 and psoriasin. Furthermore, survivin depletion by siRNA in Ras(G12V)-IκBα-derived tumors leads to smaller tumor formation characterized by lower mitotic index and reduced expression of the tumor-associated marker HIF1α, VEGF and CD51. Therefore, our results indicate survivin as a key gene in regulating SCC cancer stem cell formation and cSCC development.
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Carcinogénesis/genética , Carcinoma de Células Escamosas/genética , Regulación Neoplásica de la Expresión Génica , Proteínas Inhibidoras de la Apoptosis/genética , Queratinocitos/metabolismo , Células Madre Neoplásicas/metabolismo , Neoplasias Cutáneas/genética , Antígeno AC133 , Animales , Antígenos CD/genética , Antígenos CD/metabolismo , Carcinogénesis/metabolismo , Carcinogénesis/patología , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Técnicas de Cultivo de Célula , Proliferación Celular , Supervivencia Celular , Glicoproteínas/genética , Glicoproteínas/metabolismo , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Proteínas Inhibidoras de la Apoptosis/antagonistas & inhibidores , Proteínas Inhibidoras de la Apoptosis/metabolismo , Integrina alfaV/genética , Integrina alfaV/metabolismo , Integrina beta1/genética , Integrina beta1/metabolismo , Queratinocitos/patología , Ratones , Ratones SCID , Trasplante de Neoplasias , Células Madre Neoplásicas/patología , Factor 3 de Transcripción de Unión a Octámeros/genética , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Péptidos/genética , Péptidos/metabolismo , Cultivo Primario de Células , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Receptor Notch1/genética , Receptor Notch1/metabolismo , Transducción de Señal , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología , Survivin , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismoRESUMEN
Tumor cells able to recapitulate tumor heterogeneity have been tracked, isolated and characterized in different tumor types, and are commonly named Cancer Stem Cells or Cancer Initiating Cells (CSC/CIC). CSC/CIC are disseminated in the tumor mass and are resistant to anti-cancer therapies and adverse conditions. They are able to divide into another stem cell and a "proliferating" cancer cell. They appear to be responsible for disease recurrence and metastatic dissemination even after apparent eradication of the primary tumor. The modulation of CSC/CIC activities by the tumor microenvironment (TUMIC) is still poorly known. CSC/CIC may mutually interact with the TUMIC in a special and unique manner depending on the TUMIC cells or proteins encountered. The TUMIC consists of extracellular matrix components as well as cellular players among which endothelial, stromal and immune cells, providing and responding to signals to/from the CSC/CIC. This interplay can contribute to the mechanisms through which CSC/CIC may reside in a dormant state in a tissue for years, later giving rise to tumor recurrence or metastasis in patients. Different TUMIC components, including the connective tissue, can differentially activate CIC/CSC in different areas of a tumor and contribute to the generation of cancer heterogeneity. Here, we review possible networking activities between the different components of the tumor microenvironment and CSC/CIC, with a focus on its role in tumor heterogeneity and progression. We also summarize novel therapeutic options that could target both CSC/CIC and the microenvironment to elude resistance mechanisms activated by CSC/CIC, responsible for disease recurrence and metastases.
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Diferenciación Celular/fisiología , Matriz Extracelular/metabolismo , Neoplasias/patología , Células Madre Neoplásicas/citología , Microambiente Tumoral/fisiología , Animales , Humanos , Metástasis de la Neoplasia/patologíaRESUMEN
Antimetabolites are a class of effective anticancer drugs interfering in essential biochemical processes. 5-Fluorouracil (5-FU) and its prodrug Capecitabine are widely used in the treatment of several solid tumors (gastro-intestinal, gynecological, head and neck, breast carcinomas). Therapy with fluoropyrimidines is associated with a wide range of adverse effects, including diarrhea, dehydration, abdominal pain, nausea, stomatitis, and hand-foot syndrome. Among the 5-FU side effects, increasing attention is given to cardiovascular toxicities induced at different levels and intensities. Since the mechanisms related to 5-FU-induced cardiotoxicity are still unclear, we examined the effects of 5-FU on primary cell cultures of human cardiomyocytes and endothelial cells, which represent two key components of the cardiovascular system. We analyzed at the cellular and molecular level 5-FU effects on cell proliferation, cell cycle, survival and induction of apoptosis, in an experimental cardioncology approach. We observed autophagic features at the ultrastructural and molecular levels, in particular in 5-FU exposed cardiomyocytes. Reactive oxygen species (ROS) elevation characterized the endothelial response. These responses were prevented by a ROS scavenger. We found induction of a senescent phenotype on both cell types treated with 5-FU. In vivo, in a xenograft model of colon cancer, we showed that 5-FU treatment induced ultrastructural changes in the endothelium of various organs. Taken together, our data suggest that 5-FU can affect, both at the cellular and molecular levels, two key cell types of the cardiovascular system, potentially explaining some manifestations of 5-FU-induced cardiovascular toxicity.
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Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Fluorouracilo/farmacología , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Autofagia/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Senescencia Celular/efectos de los fármacos , Células Endoteliales/ultraestructura , Humanos , Miocitos Cardíacos/ultraestructuraRESUMEN
The human white adipose tissue (WAT) contains progenitors with cooperative roles in breast cancer (BC) angiogenesis, local and metastatic progression. The biguanide Metformin (Met), commonly used for Type 2 diabetes, might have activity against BC and was found to inhibit angiogenesis in vivo. We studied Met and another biguanide, phenformin (Phe), in vitro and in vivo in BC models. In vitro, biguanides activated AMPK, inhibited Complex 1 of the respiratory chain and induced apoptosis of BC and WAT endothelial cells. In coculture, biguanides inhibited the production of several angiogenic proteins. In vivo, biguanides inhibited local and metastatic growth of triple negative and HER2+ BC in immune-competent and immune-deficient mice orthotopically injected with BC. Biguanides inhibited local and metastatic BC growth in a genetically engineered murine model model of HER2+ BC. In vivo, biguanides increased pimonidazole binding (but not HIF-1 expression) of WAT progenitors, reduced tumor microvessel density and altered the vascular pericyte/endothelial cell ratio, so that cancer vessels displayed a dysplastic phenotype. Phe was significantly more active than Met both in vitro and in vivo. Considering their safety profile, biguanides deserve to be further investigated for BC prevention in high-risk subjects, in combination with chemo and/or targeted therapy and/or as post-therapy consolidation or maintenance therapy for the prevention of BC recurrence.
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Neoplasias de la Mama/tratamiento farmacológico , Metformina/farmacología , Neovascularización Patológica/prevención & control , Fenformina/farmacología , Microambiente Tumoral , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/irrigación sanguínea , Neoplasias de la Mama/patología , Línea Celular Tumoral , Complejo I de Transporte de Electrón/antagonistas & inhibidores , Femenino , Humanos , Ratones , Metástasis de la Neoplasia , Fosforilación , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
CD271 is the low-affinity neurotrophin (p75NTR) receptor that belongs to the tumor necrosis factor receptor superfamily. Because in human epidermis, CD271 is predominantly expressed in transit-amplifying (TA) cells, we evaluated the role of this receptor in keratinocyte differentiation and in the transition from keratinocyte stem cells (KSCs) to progeny. Calcium induced an upregulation of CD271 in subconfluent keratinocytes, which was prevented by CD271 small interfering RNA. Furthermore, CD271 overexpression provoked the switch of KSCs to TA cells, whereas silencing CD271 induced TA cells to revert to a KSC phenotype, as shown by the expression of ß1-integrin and by the increased clonogenic ability. CD271(+) keratinocytes sorted from freshly isolated TA cells expressed more survivin and keratin 15 (K15) compared with CD271(-) cells and displayed a higher proliferative capacity. Early differentiation markers and K15 were more expressed in the skin equivalent generated from CD271(+) TA than from those derived from CD271(-) TA cells. By contrast, late differentiation markers were more expressed in skin equivalents from CD271(-) than in reconstructs from CD271(+) TA cells. Finally, skin equivalents originated from CD271(-) TA cells displayed a psoriatic phenotype. These results indicate that CD271 is critical for keratinocyte differentiation and regulates the transition from KSCs to TA cells.
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Diferenciación Celular/fisiología , Células Epidérmicas , Queratinocitos/citología , Proteínas del Tejido Nervioso/metabolismo , Receptores de Factor de Crecimiento Nervioso/metabolismo , Células Madre/citología , Calcio/farmacología , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Epidermis/efectos de los fármacos , Epidermis/metabolismo , Humanos , Técnicas In Vitro , Proteínas Inhibidoras de la Apoptosis/metabolismo , Queratina-15/metabolismo , Queratinocitos/efectos de los fármacos , Queratinocitos/metabolismo , Proteínas del Tejido Nervioso/deficiencia , Proteínas del Tejido Nervioso/genética , Fenotipo , Psoriasis/patología , ARN Interferente Pequeño/farmacología , Receptores de Factor de Crecimiento Nervioso/deficiencia , Receptores de Factor de Crecimiento Nervioso/genética , Células Madre/efectos de los fármacos , Células Madre/metabolismo , SurvivinRESUMEN
It is widely accepted that the tumor microenvironment (TUMIC) plays a major role in cancer and is indispensable for tumor progression. The TUMIC involves many "players" going well beyond the malignant-transformed cells, including stromal, immune, and endothelial cells (ECs). The non-malignant cells can acquire tumor-promoting functions during carcinogenesis. In particular, these cells can "orchestrate" the "symphony" of the angiogenic switch, permitting the creation of new blood vessels that allows rapid expansion and progression toward malignancy. Considerable attention within the context of tumor angiogenesis should focus not only on the ECs, representing a fundamental unit, but also on immune cells and on the inflammatory tumor infiltrate. Immune cells infiltrating tumors typically show a tumor-induced polarization associated with attenuation of anti-tumor functions and generation of pro-tumor activities, among these angiogenesis. Here, we propose a scenario suggesting that the angiogenic switch is an immune switch arising from the pro-angiogenic polarization of immune cells. This view links immunity, inflammation, and angiogenesis to tumor progression. Here, we review the data in the literature and seek to identify the "conductors" of this "orchestra." We also suggest that interrupting the immune â inflammation â angiogenesis â tumor progression process can delay or prevent tumor insurgence and malignant disease.
RESUMEN
The biguanide metformin is used in type 2 diabetes management and has gained significant attention as a potential cancer preventive agent. Angioprevention represents a mechanism of chemoprevention, yet conflicting data concerning the antiangiogenic action of metformin have emerged. Here, we clarify some of the contradictory effects of metformin on endothelial cells and angiogenesis, using in vitro and in vivo assays combined with transcriptomic and protein array approaches. Metformin inhibits formation of capillary-like networks by endothelial cells; this effect is partially dependent on the energy sensor adenosine-monophosphate-activated protein kinase (AMPK) as shown by small interfering RNA knockdown. Gene expression profiling of human umbilical vein endothelial cells revealed a paradoxical modulation of several angiogenesis-associated genes and proteins by metformin, with short-term induction of vascular endothelial growth factor (VEGF), cyclooxygenase 2 and CXC chemokine receptor 4 at the messenger RNA level and downregulation of ADAMTS1. Antibody array analysis shows an essentially opposite regulation of numerous angiogenesis-associated proteins in endothelial and breast cancer cells including interleukin-8, angiogenin and TIMP-1, as well as selective regulation of angiopioetin-1, -2, endoglin and others. Endothelial cell production of the cytochrome P450 member CYP1B1 is upregulated by tumor cell supernatants in an AMPK-dependent manner, metformin blocks this effect. Metformin inhibits VEGF-dependent activation of extracellular signal-regulated kinase 1/2, and the inhibition of AMPK activity abrogates this event. Metformin hinders angiogenesis in matrigel pellets in vivo, prevents the microvessel density increase observed in obese mice on a high-fat diet, downregulating the number of white adipose tissue endothelial precursor cells. Our data show that metformin has an antiangiogenic activity in vitro and in vivo associated with a contradictory short-term enhancement of pro-angiogenic mediators, as well as with a differential regulation in endothelial and breast cancer cells.
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Inhibidores de la Angiogénesis/farmacología , Células Endoteliales/efectos de los fármacos , Metformina/farmacología , Neovascularización Fisiológica/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/metabolismo , Tejido Adiposo/citología , Tejido Adiposo/efectos de los fármacos , Animales , Antineoplásicos/farmacología , Hidrocarburo de Aril Hidroxilasas/genética , Hidrocarburo de Aril Hidroxilasas/metabolismo , Análisis por Conglomerados , Citocromo P-450 CYP1B1 , Modelos Animales de Enfermedad , Células Endoteliales/citología , Células Endoteliales/metabolismo , Activación Enzimática/efectos de los fármacos , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana , Humanos , Masculino , Ratones , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología , Neovascularización Patológica/tratamiento farmacológico , Neovascularización Patológica/genética , Neovascularización Patológica/metabolismo , Neovascularización Fisiológica/genética , Células Madre/citología , Células Madre/efectos de los fármacos , Células Madre/metabolismo , Factor A de Crecimiento Endotelial Vascular/farmacologíaRESUMEN
In human epidermis, keratinocyte stem cells (KSC) are characterized by high levels of ß1-integrin, resulting in the rapid adhesion to type IV collagen. Since epithelial tumors originate from KSC, we evaluated the features of rapidly adhering (RAD) keratinocytes derived from primary human squamous cell carcinoma of the skin (cSCC). RAD cells expressed higher levels of survivin, a KSC marker, as compared to non-rapidly adhering (NRAD) cells. Moreover, RAD cells proliferated to a greater extent and were more efficient in forming colonies than NRAD cells. RAD cells also migrated significantly better than NRAD cells. When seeded in a silicone chamber and grafted onto the back skin of NOD SCID mice, RAD cells formed tumors 2-4 fold bigger than those derived from NRAD cells. In tumors derived from RAD cells, the mitotic index was significantly higher than in those derived from NRAD cells, while Ki-67 and survivin expression were more pronounced in RAD tumors. This study suggests that SCC RAD stem cells play a critical role in the formation and development of epithelial tumors.
Asunto(s)
Carcinoma de Células Escamosas/patología , Neoplasias Cutáneas/patología , Células Madre/patología , Células 3T3 , Animales , Carcinogénesis/patología , Carcinoma de Células Escamosas/metabolismo , Diferenciación Celular/fisiología , Proliferación Celular , Células Cultivadas , Epidermis/metabolismo , Epidermis/patología , Humanos , Proteínas Inhibidoras de la Apoptosis/metabolismo , Integrina beta1/metabolismo , Queratinocitos/metabolismo , Queratinocitos/patología , Ratones , Ratones SCID , Proteínas Represoras/metabolismo , Neoplasias Cutáneas/metabolismo , Células Madre/metabolismo , SurvivinRESUMEN
Epidermal fatty acid-binding protein (E-FABP) is a lipid carrier, originally discovered in human epidermis. We show that E-FABP is almost exclusively expressed in postmitotic (PM) keratinocytes, corresponding to its localization in the highest suprabasal layers, while it is barely expressed in keratinocyte stem cells (KSC) and transit amplifying (TA) keratinocytes. Transfection of normal human keratinocytes with recombinant (r) E-FABP induces overexpression of K10 and involucrin. On the other hand, E-FABP inhibition by siRNA downregulates K10 and involucrin expression in normal keratinocytes through NF-κB and JNK signalling pathways. E-FABP is highly expressed in psoriatic epidermis, and it is mainly localized in stratum spinosum. Psoriatic PM keratinocytes overexpress E-FABP as compared to the same population in normal epidermis. E-FABP inhibition in psoriatic keratinocytes markedly reduces differentiation, while it upregulates psoriatic markers such as survivin and K16. However, under high-calcium conditions, E-FABP silencing downregulates K10 and involucrin, while survivin and K16 expression is completely abolished. These data strongly indicate that E-FABP plays an important role in keratinocyte differentiation. Moreover, E-FABP modulates differentiation in psoriatic keratinocytes.
Asunto(s)
Proteínas de Unión a Ácidos Grasos/metabolismo , Queratinocitos/citología , Queratinocitos/fisiología , Psoriasis/metabolismo , Psoriasis/patología , Diferenciación Celular/fisiología , Células Cultivadas , Proteínas de Unión a Ácidos Grasos/antagonistas & inhibidores , Proteínas de Unión a Ácidos Grasos/genética , Humanos , Queratina-10/metabolismo , Queratinocitos/patología , Precursores de Proteínas/metabolismo , ARN Interferente Pequeño/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismoRESUMEN
Although the concept of cancer stem cells (CSCs) is well-accepted for many tumors, the existence of such cells in human melanoma has been the subject of debate. In this study, we demonstrate the existence of human melanoma cells that fulfill the criteria for CSCs (self-renewal and differentiation) by serially xenotransplanting cells into nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice. These cells possess high aldehyde dehydrogenase (ALDH) activity with ALDH1A1 and ALDH1A3 being the predominant ALDH isozymes. ALDH-positive melanoma cells are more tumorigenic than ALDH-negative cells in both NOD/SCID mice and NSG mice. Biological analyses of the ALDH-positive melanoma cells reveal the ALDH isozymes to be key molecules regulating the function of these cells. Silencing ALDH1A by siRNA or shRNA leads to cell cycle arrest, apoptosis, decreased cell viability in vitro, and reduced tumorigenesis in vivo. ALDH-positive melanoma cells are more resistant to chemotherapeutic agents and silencing ALDH1A by siRNA sensitizes melanoma cells to drug-induced cell death. Furthermore, we, for the first time, examined the molecular signatures of ALDH-positive CSCs from patient-derived tumor specimens. The signatures of melanoma CSCs include retinoic acid (RA)-driven target genes with RA response elements and genes associated with stem cell function. These findings implicate that ALDH isozymes are not only biomarkers of CSCs but also attractive therapeutic targets for human melanoma. Further investigation of these isozymes and genes will enhance our understanding of the molecular mechanisms governing CSCs and reveal new molecular targets for therapeutic intervention of cancer.
Asunto(s)
Aldehído Deshidrogenasa/genética , Transformación Celular Neoplásica/genética , Melanoma/genética , Células Madre Neoplásicas/efectos de los fármacos , Neoplasias Cutáneas/genética , Aldehído Deshidrogenasa/antagonistas & inhibidores , Familia de Aldehído Deshidrogenasa 1 , Aldehído Oxidorreductasas , Animales , Apoptosis/efectos de los fármacos , Transformación Celular Neoplásica/efectos de los fármacos , Dacarbazina/análogos & derivados , Dacarbazina/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Silenciador del Gen , Humanos , Isoenzimas/antagonistas & inhibidores , Isoenzimas/genética , Melanoma/enzimología , Melanoma/patología , Ratones , Ratones Endogámicos NOD , Ratones SCID , Trasplante de Neoplasias , Células Madre Neoplásicas/enzimología , Células Madre Neoplásicas/patología , ARN Interferente Pequeño/genética , Elementos de Respuesta , Retinal-Deshidrogenasa , Neoplasias Cutáneas/enzimología , Neoplasias Cutáneas/patología , Temozolomida , Tretinoina/química , Tretinoina/farmacologíaRESUMEN
Side population (SP) cells are identified as cells capable of excluding the fluorescent Hoechst dye and anticancer drugs, and it represents hematopoietic stem cells and chemoresistant cells from several solid tumors. In this study, we confirmed the presence of SP cells in tumors from melanoma patients. Melanoma SP cells overexpressed ATP-binding-cassette (ABC) transporters, ABCB1 and ABCB5. We generated a direct in vivo xenograft model, and demonstrated that SP cells were resistant to paclitaxel, a substrate of ABCB1, both in vitro and in vivo. However, melanoma SP cells were also resistant to temozolomide, which is not a substrate for ABC transporters, through IL-8 upregulation. In addition, gene profiling studies identified three signaling pathways (NF-κB, α6-ß4-integrin, and IL-1) as differentially upregulated in melanoma SP cells, and there was a significant increase of PCDHB11 and decrease of FUK and TBX2 in these cells. Therefore, we provide evidence that SP is an enriched source of chemoresistant cells in human melanomas, and suggest that the selected genes and signaling pathways of SP cells may be a potential target for effective melanoma therapies. To our knowledge, this is a previously unreported study to isolate SP cells from melanoma patients and to investigate the gene expression profiling of these cells.
Asunto(s)
Resistencia a Antineoplásicos/fisiología , Melanoma/patología , Melanoma/fisiopatología , Células de Población Lateral/patología , Células de Población Lateral/fisiología , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/fisiopatología , Subfamilia B de Transportador de Casetes de Unión a ATP , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/fisiología , Animales , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Colorantes , Dacarbazina/análogos & derivados , Dacarbazina/uso terapéutico , Femenino , Humanos , Técnicas In Vitro , Interleucina-8/fisiología , Melanoma/tratamiento farmacológico , Ratones , Ratones Desnudos , Paclitaxel/uso terapéutico , Neoplasias Cutáneas/tratamiento farmacológico , Temozolomida , Regulación hacia Arriba/fisiología , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Survivin belongs to the inhibitor of apoptosis (IAP) protein family, and, in addition to the antiapoptotic functions, it also regulates the cell cycle. The survivin gene generates five major isoforms with diverse and opposite functions. Survivin is highly expressed in cancer and in few normal adult tissues, including skin. It is mostly detected in the nucleus of keratinocyte stem cells (KSCs), but it is also expressed in melanocytes and fibroblasts. Survivin isoforms are differentially detected in subpopulations of human keratinocytes, exerting contrasting activities. Survivin has an important role in the regulation of cell cycle in keratinocytes, and it protects these cells from anoikis and UV-induced apoptosis. In melanoma, survivin is abundantly expressed, and its subcellular localization varies depending upon tumor thickness and invasiveness. Survivin overexpression has been shown in squamous cell carcinoma (SCC), and it is also involved in UVB-induced carcinogenesis. The presence of survivin both in the nucleus and in the cytoplasm throughout the epidermal layers of psoriatic lesions suggests the involvement of this protein in the keratinocyte alterations typical of this disease. Additional studies on the expression of survivin isoforms and their subcellular localization in relation to function will confirm the key role of survivin in the skin and will open the field to new therapeutic strategies for many cutaneous conditions.