RESUMO
Extracellular matrix (ECM) is a major component of the tumor environment, promoting the establishment of a pro-invasive behavior. Such environment is supported by both tumor- and stromal-derived metabolites, particularly lactate. In prostate cancer (PCa), cancer-associated fibroblasts (CAFs) are major contributors of secreted lactate, able to impact on metabolic and transcriptional regulation in cancer cells. Here, we describe a mechanism by which CAF-secreted lactate promotes in PCa cells the expression of genes coding for the collagen family. Lactate-exploiting PCa cells rely on increased α-ketoglutarate (α-KG) which activates the α-KG-dependent collagen prolyl-4-hydroxylase (P4HA1) to support collagen hydroxylation. De novo synthetized collagen plays a signaling role by activating discoidin domain receptor 1 (DDR1), supporting stem-like and invasive features of PCa cells. Inhibition of lactate-induced collagen hydroxylation and DDR1 activation reduces the metastatic colonization of PCa cells. Overall, these results provide a new understanding of the link between collagen remodeling/signaling and the nutrient environment exploited by PCa.
Assuntos
Colágeno , Matriz Extracelular , Ácido Láctico , Metástase Neoplásica , Neoplasias da Próstata , Masculino , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/genética , Humanos , Matriz Extracelular/metabolismo , Colágeno/metabolismo , Ácido Láctico/metabolismo , Linhagem Celular Tumoral , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Transdução de Sinais , Regulação Neoplásica da Expressão Gênica , Animais , Camundongos , Microambiente Tumoral , Ácidos Cetoglutáricos/metabolismo , HidroxilaçãoRESUMO
Triple-negative breast cancer (TNBC) has limited therapeutic options, is highly metastatic and characterized by early recurrence. Lipid metabolism is generally deregulated in TNBC and might reveal vulnerabilities to be targeted or used as biomarkers with clinical value. Ferroptosis is a type of cell death caused by iron-dependent lipid peroxidation which is facilitated by the presence of polyunsaturated fatty acids (PUFA). Here we identify fatty acid desaturases 1 and 2 (FADS1/2), which are responsible for PUFA biosynthesis, to be highly expressed in a subset of TNBC with a poorer prognosis. Lipidomic analysis, coupled with functional metabolic assays, showed that FADS1/2 high-expressing TNBC are susceptible to ferroptosis-inducing agents and that targeting FADS1/2 by both genetic interference and pharmacological approach renders those tumors ferroptosis-resistant while unbalancing PUFA/MUFA ratio by the supplementation of exogenous PUFA sensitizes resistant tumors to ferroptosis induction. Last, inhibiting lipid droplet (LD) formation and turnover suppresses the buffering capacity of LD and potentiates iron-dependent cell death. These findings have been validated in vitro and in vivo in mouse- and human-derived clinically relevant models and in a retrospective cohort of TNBC patients.
Assuntos
Dessaturase de Ácido Graxo Delta-5 , Ácidos Graxos Dessaturases , Ferroptose , Metabolismo dos Lipídeos , Neoplasias de Mama Triplo Negativas , Animais , Feminino , Humanos , Camundongos , Linhagem Celular Tumoral , Ácidos Graxos Dessaturases/metabolismo , Ácidos Graxos Dessaturases/genética , Ferroptose/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genéticaRESUMO
Targeting aromatase deprives ER+ breast cancers of estrogens and is an effective therapeutic approach for these tumors. However, drug resistance is an unmet clinical need. Lipidomic analysis of long-term estrogen-deprived (LTED) ER+ breast cancer cells, a model of aromatase inhibitor resistance, revealed enhanced intracellular lipid storage. Functional metabolic analysis showed that lipid droplets together with peroxisomes, which we showed to be enriched and active in the LTED cells, controlled redox homeostasis and conferred metabolic adaptability to the resistant tumors. This reprogramming was controlled by acetyl-CoA-carboxylase-1 (ACC1), whose targeting selectively impaired LTED survival. However, the addition of branched- and very long-chain fatty acids reverted ACC1 inhibition, a process that was mediated by peroxisome function and redox homeostasis. The therapeutic relevance of these findings was validated in aromatase inhibitor-treated patient-derived samples. Last, targeting ACC1 reduced tumor growth of resistant patient-derived xenografts, thus identifying a targetable hub to combat the acquisition of estrogen independence in ER+ breast cancers.
Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Inibidores da Aromatase/farmacologia , Inibidores da Aromatase/uso terapêutico , Peroxissomos/metabolismo , Peroxissomos/patologia , Acetil-CoA Carboxilase , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/patologia , Linhagem Celular Tumoral , Estrogênios/metabolismo , Resistencia a Medicamentos AntineoplásicosRESUMO
BACKGROUND AND AIMS: Cancer cells reprogram their metabolic pathways to support bioenergetic and biosynthetic needs and to maintain their redox balance. In several human tumors, the Keap1-Nrf2 system controls proliferation and metabolic reprogramming by regulating the pentose phosphate pathway (PPP). However, whether this metabolic reprogramming also occurs in normal proliferating cells is unclear. APPROACH AND RESULTS: To define the metabolic phenotype in normal proliferating hepatocytes, we induced cell proliferation in the liver by 3 distinct stimuli: liver regeneration by partial hepatectomy and hepatic hyperplasia induced by 2 direct mitogens: lead nitrate (LN) or triiodothyronine. Following LN treatment, well-established features of cancer metabolic reprogramming, including enhanced glycolysis, oxidative PPP, nucleic acid synthesis, NAD + /NADH synthesis, and altered amino acid content, as well as downregulated oxidative phosphorylation, occurred in normal proliferating hepatocytes displaying Nrf2 activation. Genetic deletion of Nrf2 blunted LN-induced PPP activation and suppressed hepatocyte proliferation. Moreover, Nrf2 activation and following metabolic reprogramming did not occur when hepatocyte proliferation was induced by partial hepatectomy or triiodothyronine. CONCLUSIONS: Many metabolic changes in cancer cells are shared by proliferating normal hepatocytes in response to a hostile environment. Nrf2 activation is essential for bridging metabolic changes with crucial components of cancer metabolic reprogramming, including the activation of oxidative PPP. Our study demonstrates that matured hepatocytes exposed to LN undergo cancer-like metabolic reprogramming and offers a rapid and useful in vivo model to study the molecular alterations underpinning the differences/similarities of metabolic changes in normal and neoplastic hepatocytes.
Assuntos
Fator 2 Relacionado a NF-E2 , Neoplasias , Animais , Humanos , Ratos , Proliferação de Células , Hepatócitos/metabolismo , Hiperplasia , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Reprogramação Metabólica , Neoplasias/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Tri-Iodotironina/genética , Tri-Iodotironina/metabolismoRESUMO
Resistance to endocrine treatments and CDK4/6 inhibitors is considered a near-inevitability in most patients with estrogen receptor positive breast cancers (ER + BC). By genomic and metabolomics analyses of patients' tumours, metastasis-derived patient-derived xenografts (PDX) and isogenic cell lines we demonstrate that a fraction of metastatic ER + BC is highly reliant on oxidative phosphorylation (OXPHOS). Treatment by the OXPHOS inhibitor IACS-010759 strongly inhibits tumour growth in multiple endocrine and palbociclib resistant PDX. Mutations in the PIK3CA/AKT1 genes are significantly associated with response to IACS-010759. At the metabolic level, in vivo response to IACS-010759 is associated with decreased levels of metabolites of the glutathione, glycogen and pentose phosphate pathways in treated tumours. In vitro, endocrine and palbociclib resistant cells show increased OXPHOS dependency and increased ROS levels upon IACS-010759 treatment. Finally, in ER + BC patients, high expression of OXPHOS associated genes predict poor prognosis. In conclusion, these results identify OXPHOS as a promising target for treatment resistant ER + BC patients.
Assuntos
Neoplasias da Mama , Animais , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Fosforilação Oxidativa , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Receptores de Estrogênio/metabolismo , Modelos Animais de DoençasRESUMO
OBJECTIVE: Pancreatic ductal adenocarcinoma (PDAC) is an aggressive disease with limited therapeutic options. However, metabolic adaptation to the harsh PDAC environment can expose liabilities useful for therapy. Targeting the key metabolic regulator mechanistic target of rapamycin complex 1 (mTORC1) and its downstream pathway shows efficacy only in subsets of patients but gene modifiers maximising response remain to be identified. DESIGN: Three independent cohorts of PDAC patients were studied to correlate PI3K-C2γ protein abundance with disease outcome. Mechanisms were then studied in mouse (KPC mice) and cellular models of PDAC, in presence or absence of PI3K-C2γ (WT or KO). PI3K-C2γ-dependent metabolic rewiring and its impact on mTORC1 regulation were assessed in conditions of limiting glutamine availability. Finally, effects of a combination therapy targeting mTORC1 and glutamine metabolism were studied in WT and KO PDAC cells and preclinical models. RESULTS: PI3K-C2γ expression was reduced in about 30% of PDAC cases and was associated with an aggressive phenotype. Similarly, loss of PI3K-C2γ in KPC mice enhanced tumour development and progression. The increased aggressiveness of tumours lacking PI3K-C2γ correlated with hyperactivation of mTORC1 pathway and glutamine metabolism rewiring to support lipid synthesis. PI3K-C2γ-KO tumours failed to adapt to metabolic stress induced by glutamine depletion, resulting in cell death. CONCLUSION: Loss of PI3K-C2γ prevents mTOR inactivation and triggers tumour vulnerability to RAD001 (mTOR inhibitor) and BPTES/CB-839 (glutaminase inhibitors). Therefore, these results might open the way to personalised treatments in PDAC with PI3K-C2γ loss.
Assuntos
Carcinoma Ductal Pancreático , Everolimo , Lipídeos , Lisossomos , Inibidores de MTOR , Neoplasias Pancreáticas , Fosfatidilinositol 3-Quinases , Animais , Camundongos , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Glutamina/metabolismo , Lipídeos/biossíntese , Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Nutrientes , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Everolimo/uso terapêutico , Inibidores de MTOR/uso terapêutico , Glutaminase , Neoplasias PancreáticasRESUMO
Major advances have been made in precision medicine of breast cancer patients with a series of molecular targeted therapies now in clinical use or in late clinical development. These new therapeutic measures need to be integrated with local treatments, particularly with radiation therapy in both curative and advanced settings. Although a synergistic effect could be obtained between targeted therapies and irradiation, potential safety concerns should be carefully considered. At present, scarce evidence exists due to a lack of quality assurance on radiation therapy in pivotal trials of new drugs and missing reports on safety in case of concurrent radiation therapy, commonly administered with heterogenous doses and fractionations, especially in advanced disease. A major contribution for effectively combining radiation and targeted therapies in breast cancer could derive from clinically relevant preclinical studies. This review integrates preclinical and clinical evidence on how targeted agents and radiation therapy could be combined to help physicians in their daily clinical practice and to improve the clinical management of patients.
Assuntos
Antineoplásicos , Neoplasias da Mama , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/radioterapia , Terapia Combinada , Feminino , Humanos , Terapia de Alvo MolecularRESUMO
Lactate is an abundant oncometabolite in the tumor environment. In prostate cancer, cancer-associated fibroblasts (CAF) are major contributors of secreted lactate, which can be taken up by cancer cells to sustain mitochondrial metabolism. However, how lactate impacts transcriptional regulation in tumors has yet to be fully elucidated. Here, we describe a mechanism by which CAF-secreted lactate is able to increase the expression of genes involved in lipid metabolism in prostate cancer cells. This regulation enhanced intracellular lipid accumulation in lipid droplets (LD) and provided acetyl moieties for histone acetylation, establishing a regulatory loop between metabolites and epigenetic modification. Inhibition of this loop by targeting the bromodomain and extraterminal protein family of histone acetylation readers suppressed the expression of perilipin 2 (PLIN2), a crucial component of LDs, disrupting lactate-dependent lipid metabolic rewiring. Inhibition of this CAF-induced metabolic-epigenetic regulatory loop in vivo reduced growth and metastasis of prostate cancer cells, demonstrating its translational relevance as a therapeutic target in prostate cancer. Clinically, PLIN2 expression was elevated in tumors with a higher Gleason grade and in castration-resistant prostate cancer compared with primary prostate cancer. Overall, these findings show that lactate has both a metabolic and an epigenetic role in promoting prostate cancer progression. SIGNIFICANCE: This work shows that stromal-derived lactate induces accumulation of lipid droplets, stimulates epigenetic rewiring, and fosters metastatic potential in prostate cancer.
Assuntos
Metabolismo dos Lipídeos , Neoplasias da Próstata , Epigênese Genética , Humanos , Ácido Láctico/metabolismo , Metabolismo dos Lipídeos/genética , Masculino , Próstata/patologia , Neoplasias da Próstata/patologiaRESUMO
Vascular endothelial growth factor receptor 2 (VEGFR2) activating mutations are emerging as important oncogenic driver events. Understanding the biological implications of such mutations may help to pinpoint novel therapeutic targets. Here we show that activated VEGFR2 via the pro-oncogenic R1051Q mutation induces relevant metabolic changes in melanoma cells. The expression of VEGFR2R1051Q leads to higher energy metabolism and ATP production compared to control cells expressing VEGFR2WT. Furthermore, activated VEGFR2R1051Q augments the dependence on glutamine (Gln) of melanoma cells, thus increasing Gln uptake and their sensitivity to Gln deprivation and to inhibitors of glutaminase, the enzyme initiating Gln metabolism by cells. Overall, these results highlight Gln addiction as a metabolic vulnerability of tumors harboring the activating VEGFR2R1051Q mutation and suggest novel therapeutic approaches for those patients harboring activating mutations of VEGFR2.
Assuntos
Metabolismo Energético , Mutação com Ganho de Função , Glutamina/metabolismo , Melanoma/metabolismo , Neoplasias Cutâneas/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Trifosfato de Adenosina/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Metabolismo Energético/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Glutaminase/antagonistas & inibidores , Glutaminase/metabolismo , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/patologia , Transdução de Sinais , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genéticaRESUMO
Lipid metabolic reprogramming is an established trait of cancer metabolism that guides response and resistance to antitumoral therapies. Enhanced lipogenesis, increased lipid content (either free or stored into lipid droplets), and lipid-dependent catabolism sustain therapy desensitization and the emergence of a resistant phenotype of tumor cells exposed to chemotherapy or targeted therapies. Aberrant lipid metabolism, therefore, has emerged as a potential metabolic vulnerability of therapy-resistant cancers that could be exploited for therapeutic interventions or for identifying tumors more likely to respond to further lines of therapies. This review gathers recent findings on the role of aberrant lipid metabolism in influencing antitumoral therapy response and in sustaining the emergence of resistance.
Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Antineoplásicos/uso terapêutico , Humanos , Metabolismo dos Lipídeos/genética , Terapia de Alvo Molecular/métodos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Efeito Warburg em Oncologia/efeitos dos fármacosRESUMO
The majority of breast cancers express the estrogen receptor (ER) and are dependent on estrogen for their growth and survival. Endocrine therapy (ET) is the standard of care for these tumors. However, a superior outcome is achieved in a subset of ER positive (ER+)/human epidermal growth factor receptor 2 negative (HER2-) metastatic breast cancer patients when ET is administrated in combination with a cyclin-dependent kinases 4 and 6 (CDK4/6) inhibitor, such as palbociclib. Moreover, CDK4/6 inhibitors are currently being tested in ER+/HER2+ breast cancer and reported encouraging results. Despite the clinical advances of a combinatorial therapy using ET plus CDK4/6 inhibitors, potential limitations (i.e., resistance) could emerge and the metabolic adaptations underlying such resistance warrant further elucidation. Here we investigate the glucose-dependent catabolism in a series of isogenic ER+ breast cancer cell lines sensitive to palbociclib and in their derivatives with acquired resistance to the drug. Importantly, ER+/HER2- and ER+/HER2+ cell lines show a different degree of glucose dependency. While ER+/HER2- breast cancer cells are characterized by enhanced aerobic glycolysis at the time of palbociclib sensitivity, ER+/HER2+ cells enhance their glycolytic catabolism at resistance. This metabolic phenotype was shown to have prognostic value and was targeted with multiple approaches offering a series of potential scenarios that could be of clinical relevance.
Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Glucose/metabolismo , Piperazinas/uso terapêutico , Piridinas/uso terapêutico , Antineoplásicos/farmacologia , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Feminino , Humanos , Piperazinas/farmacologia , Piridinas/farmacologia , TransfecçãoRESUMO
Endo-, phyto- and synthetic cannabinoids have been proposed as promising anti-cancer agents able to impair cancer cells' behavior without affecting their non-transformed counterparts. However, cancer outcome depends not only on cancer cells' activity, but also on the stromal cells, which coevolve with cancer cells to sustain tumor progression. Here, we show for the first time that cannabinoid treatment impairs the activation and the reactivity of cancer-associated fibroblasts (CAFs), the most represented stromal component of prostate tumor microenvironment. Using prostate cancer-derived CAFs, we demonstrated that WIN 55-212.2 mesylate, a synthetic full agonist of cannabinoid receptors (CBs) 1 and 2, downregulates α-smooth muscle actin and matrix metalloprotease-2 expression, and it inhibits CAF migration, essential features to ensure the activated and reactive CAF phenotype. Furthermore, by impairing stromal reactivity, WIN 55-212.2 mesylate also negatively affects CAF-mediated cancer cells' invasiveness. Using selective antagonists of CBs, we proved that CAFs response to WIN 55-212.2 mesylate is mainly mediated by CB2. Finally, we suggest that endocannabinoids self-sustain both prostate tumor cells migration and CAFs phenotype by an autocrine loop. Overall, our data strongly support the use of cannabinoids as anti-tumor agents in prostate cancer, since they are able to simultaneously strike both cancer and stromal cells.
Assuntos
Fibroblastos Associados a Câncer/efeitos dos fármacos , Fibroblastos Associados a Câncer/metabolismo , Canabinoides/farmacologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Androgênios/metabolismo , Benzoxazinas/farmacologia , Biomarcadores , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Progressão da Doença , Humanos , Masculino , Morfolinas/farmacologia , Naftalenos/farmacologia , Fenótipo , Receptor CB2 de Canabinoide/metabolismo , Microambiente Tumoral/efeitos dos fármacosRESUMO
Metabolic reprogramming as well as the flexible utilisation of fuel sources by tumour cells has been considered not only intrinsic to malignant cells but also sustained by resident and/or recruited stromal cells. The complexity of tumour-stroma cross-talk is experienced by neoplastic cells through profound changes in the own metabolic machinery. In such context, mitochondria are dynamic organelles that receive, orchestrate and exchange a multiplicity of stromal cues within the tumour cells to finely regulate key metabolic and signalling pathways, allowing malignant cells to adapt and thrive in an ever-changing environment. In this review, we focus on how tumour mitochondria are coached by stromal metabolic supply and how this re-education sustains tumour malignant traits.
Assuntos
Transição Epitelial-Mesenquimal , Mitocôndrias/metabolismo , Neoplasias/metabolismo , Células Estromais/metabolismo , Humanos , Neoplasias/patologiaRESUMO
Endocrine therapy (ET) is the standard of care for estrogen receptor-positive (ER+) breast cancers. Despite its efficacy, â¼40% of women relapse with ET-resistant (ETR) disease. A global transcription analysis in ETR cells reveals a downregulation of the neutral and basic amino acid transporter SLC6A14 governed by enhanced miR-23b-3p expression, resulting in impaired amino acid metabolism. This altered amino acid metabolism in ETR cells is supported by the activation of autophagy and the enhanced import of acidic amino acids (aspartate and glutamate) mediated by the SLC1A2 transporter. The clinical significance of these findings is validated by multiple orthogonal approaches in a large cohort of ET-treated patients, in patient-derived xenografts, and in in vivo experiments. Targeting these amino acid metabolic dependencies resensitizes ETR cells to therapy and impairs the aggressive features of ETR cells, offering predictive biomarkers and potential targetable pathways to be exploited to combat or delay ETR in ER+ breast cancers.
Assuntos
Sistemas de Transporte de Aminoácidos/metabolismo , Ácido Aspártico/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Transportador 2 de Aminoácido Excitatório/metabolismo , Ácido Glutâmico/metabolismo , Sistemas de Transporte de Aminoácidos/genética , Sistemas de Transporte de Aminoácidos Neutros/genética , Animais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Transportador 2 de Aminoácido Excitatório/genética , Feminino , Fator de Transcrição GATA2/genética , Fator de Transcrição GATA2/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , MicroRNAs/genética , MicroRNAs/metabolismo , Metástase Neoplásica , Prognóstico , Transcriptoma/genética , Transplante HeterólogoRESUMO
Integrins, following binding to proteins of the extracellular matrix (ECM) including collagen, laminin and fibronectin (FN), are able to transduce molecular signals inside the cells and to regulate several biological functions such as migration, proliferation and differentiation. Besides activation of adaptor molecules and kinases, integrins transactivate Receptor Tyrosine Kinases (RTK). In particular, adhesion to the ECM may promote RTK activation in the absence of growth factors. The Colony-Stimulating Factor-1 Receptor (CSF-1R) is a RTK that supports the survival, proliferation, and motility of monocytes/macrophages, which are essential components of innate immunity and cancer development. Macrophage interaction with FN is recognized as an important aspect of host defense and wound repair. The aim of the present study was to investigate on a possible cross-talk between FN-elicited signals and CSF-1R in macrophages. FN induced migration in BAC1.2F5 and J774 murine macrophage cell lines and in human primary macrophages. Adhesion to FN determined phosphorylation of the Focal Adhesion Kinase (FAK) and Src Family Kinases (SFK) and activation of the SFK/FAK complex, as witnessed by paxillin phosphorylation. SFK activity was necessary for FAK activation and macrophage migration. Moreover, FN-induced migration was dependent on FAK in either murine macrophage cell lines or human primary macrophages. FN also induced FAK-dependent/ligand-independent CSF-1R phosphorylation, as well as the interaction between CSF-1R and ß1. CSF-1R activity was necessary for FN-induced macrophage migration. Indeed, genetic or pharmacological inhibition of CSF-1R prevented FN-induced macrophage migration. Our results identified a new SFK-FAK/CSF-1R signaling pathway that mediates FN-induced migration of macrophages.
Assuntos
Movimento Celular , Fibronectinas/farmacologia , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Macrófagos/citologia , Receptor de Fator Estimulador de Colônias de Macrófagos/metabolismo , Transdução de Sinais , Quinases da Família src/metabolismo , Animais , Movimento Celular/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Ativação Enzimática/efeitos dos fármacos , Proteína-Tirosina Quinases de Adesão Focal/antagonistas & inibidores , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/enzimologia , Camundongos , Modelos Biológicos , Células NIH 3T3 , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacosRESUMO
Aromatase inhibitors (AI) have become the first-line endocrine treatment of choice for postmenopausal estrogen receptor-positive (ER(+)) breast cancer patients, but resistance remains a major challenge. Metabolic reprogramming is a hallmark of cancer and may contribute to drug resistance. Here, we investigated the link between altered breast cancer metabolism and AI resistance using AI-resistant and sensitive breast cancer cells, patient tumor samples, and AI-sensitive human xenografts. We found that long-term estrogen deprivation (LTED), a model of AI resistance, was associated with increased glycolysis dependency. Targeting the glycolysis-priming enzyme hexokinase-2 (HK2) in combination with the AI, letrozole, synergistically reduced cell viability in AI-sensitive models. Conversely, MCF7-LTED cells, which displayed a high degree of metabolic plasticity, switched to oxidative phosphorylation when glycolysis was impaired. This effect was ER dependent as breast cancer cells with undetectable levels of ER failed to exhibit metabolic plasticity. MCF7-LTED cells were also more motile than their parental counterparts and assumed amoeboid-like invasive abilities upon glycolysis inhibition with 2-deoxyglucose (2-DG). Mechanistic investigations further revealed an important role for miR-155 in metabolic reprogramming. Suppression of miR-155 resulted in sensitization of MCF7-LTED cells to metformin treatment and impairment of 2-DG-induced motility. Notably, high baseline miR-155 expression correlated with poor response to AI therapy in a cohort of ER(+) breast cancers treated with neoadjuvant anastrozole. These findings suggest that miR-155 represents a biomarker potentially capable of identifying the subset of breast cancers most likely to adapt to and relapse on AI therapy.