RESUMEN
Cancer cells encounter metabolic stresses such as hypoxia and nutrient limitations because they grow and divide more quickly than their normal counterparts. In response to glucose restriction, we found that nuclear translocation of the glycolic enzyme, pyruvate kinase M2 (PKM2), helped cancer cells survive under the metabolic stress. Restriction of glucose stimulated AMPK activation and resulted in co-translocation of AMPK and PKM2 through Ran-mediated nuclear transport. Nuclear PKM2 subsequently bound to Oct4 and promoted the expression of cancer stemness-related genes, which might enrich the cancer stem cell population under the metabolic stress. Nuclear PKM2 was also capable of promoting cancer metastasis in an orthotopic xenograft model. In summary, we found that cytosolic AMPK helped PKM2 carry out its nonmetabolic functions in the nucleus under glucose restriction and that nuclear PKM2 promoted cancer stemness and metastasis. These findings suggested a potential new targeting pathway for cancer therapy in the future.
Asunto(s)
Adaptación Fisiológica/fisiología , Adenilato Quinasa/metabolismo , Proteínas Portadoras/metabolismo , Proteínas de la Membrana/metabolismo , Células Madre Neoplásicas/metabolismo , Estrés Fisiológico/fisiología , Hormonas Tiroideas/metabolismo , Transporte Activo de Núcleo Celular/fisiología , Animales , Línea Celular Tumoral , Núcleo Celular/metabolismo , Xenoinjertos , Humanos , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Proteínas de Unión a Hormona TiroideRESUMEN
Apigenin (4',5,7-trihydroxyflavone), a flavonoid commonly found in fruits and vegetables, has anticancer properties in various malignant cancer cells. However, the molecular basis of the anticancer effect remains to be elucidated. In this study, we investigated the cellular mechanisms underlying the induction of cell cycle arrest by apigenin. Our results showed that apigenin at the nonapoptotic induction concentration inhibited cell proliferation and induced cell cycle arrest at the G2/M phase in the MDA-MB-231 breast cancer cell line. Immunoblot analysis indicated that apigenin suppressed the expression of cyclin A, cyclin B, and cyclin-dependent kinase-1 (CDK1), which control the G2-to-M phase transition in the cell cycle. In addition, apigenin upregulated p21WAF1/CIP1 and increased the interaction of p21WAF1/CIP1 with proliferating cell nuclear antigen (PCNA), which inhibits cell cycle progression. Furthermore, apigenin significantly inhibited histone deacetylase (HDAC) activity and induced histone H3 acetylation. The subsequent chromatin immunoprecipitation (ChIP) assay indicated that apigenin increased acetylation of histone H3 in the p21WAF1/CIP1 promoter region, resulting in the increase of p21WAF1/CIP1 transcription. In a tumor xenograft model, apigenin effectively delayed tumor growth. In these apigenin-treated tumors, we also observed reductions in the levels of cyclin A and cyclin B and increases in the levels of p21WAF1/CIP1 and acetylated histone H3. These findings demonstrate for the first time that apigenin can be used in breast cancer prevention and treatment through epigenetic regulation. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 434-444, 2017.
Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apigenina/farmacología , Puntos de Control del Ciclo Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Fase G2/efectos de los fármacos , Histonas/metabolismo , Acetilación , Animales , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Epigénesis Genética/efectos de los fármacos , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Histona Desacetilasas/análisis , Histona Desacetilasas/metabolismo , Humanos , Ratones , Ratones Endogámicos BALB C , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Glutaminolysis that catabolizes glutamine to glutamate plays a critical role in cancer progression. Glutaminase 2 (GLS2) has been reported as a tumor suppressor. Recent studies implied that GLS2 may display its multifunction besides classical metabolic feature by different localizations and potential protein binding domains. Here, we showed that GLS2 expression correlates inversely with stage, vascular invasion, tumor size and poor prognosis in human hepatocellular carcinoma (HCC) tissues. We found that GLS2 significantly represses cell migration, invasion and metastasis of HCC through downregulation of Snail in vitro and in vivo. Moreover, our results demonstrated that GLS2 interacts with Dicer and stabilizes Dicer protein to facilitate miR-34a maturation and subsequently represses Snail expression in a glutaminase activity independent manner. Our findings indicate that non-glutaminolysis function of GLS2 inhibits migration and invasion of HCC cells by repressing the epithelial-mesenchymal transition via the Dicer-miR-34a-Snail axis.
Asunto(s)
Carcinoma Hepatocelular/enzimología , Movimiento Celular , ARN Helicasas DEAD-box/metabolismo , Glutaminasa/metabolismo , Neoplasias Hepáticas/enzimología , Ribonucleasa III/metabolismo , Factores de Transcripción de la Familia Snail/metabolismo , Animales , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/secundario , ARN Helicasas DEAD-box/genética , Regulación hacia Abajo , Transición Epitelial-Mesenquimal , Femenino , Regulación Neoplásica de la Expresión Génica , Glutaminasa/genética , Células HEK293 , Células Hep G2 , Humanos , Estimación de Kaplan-Meier , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Masculino , Ratones Endogámicos NOD , Ratones SCID , MicroARNs/genética , MicroARNs/metabolismo , Invasividad Neoplásica , Estadificación de Neoplasias , Estabilidad Proteica , Interferencia de ARN , Ribonucleasa III/genética , Transducción de Señal , Factores de Transcripción de la Familia Snail/genética , Factores de Tiempo , Transfección , Carga TumoralRESUMEN
Angiopoietin-like protein 1 (ANGPTL1) has been shown to act as a tumor suppressor by inhibiting angiogenesis, cancer invasion, and metastasis. However, little is known about the effects of ANGPTL1 on sorafenib resistance and cancer stem cell properties in hepatocellular carcinoma (HCC) and the mechanism underlying these effects. Here, we show that ANGPTL1 expression positively correlates with sorafenib sensitivity in HCC cells and human HCC tissues. ANGPTL1 significantly decreases epithelial-mesenchymal transition (EMT)-driven sorafenib resistance, cancer stemness, and tumor growth of HCC cells by repressing Slug expression. ANGPTL1 directly interacts with and inactivates MET receptor, which contributes to Slug suppression through inhibition of the extracellular receptor kinase/protein kinase B (ERK/AKT)-dependent early growth response protein 1 (Egr-1) pathway. ANGPTL1 expression inversely correlates with Slug expression, poor sorafenib responsiveness, and poor clinical outcomes in HCC patients. CONCLUSION: ANGPTL1 inhibits sorafenib resistance and cancer stemness in HCC cells by repressing EMT through inhibition of the MET receptor-AKT/ERK-Egr-1-Slug signaling cascade. ANGPTL1 may serve as a novel MET receptor inhibitor for advanced HCC therapy. (Hepatology 2016;64:1637-1651).
Asunto(s)
Angiopoyetinas/fisiología , Antineoplásicos/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Resistencia a Antineoplásicos , Neoplasias Hepáticas/tratamiento farmacológico , Niacinamida/análogos & derivados , Compuestos de Fenilurea/uso terapéutico , Proteínas Proto-Oncogénicas c-met/fisiología , Proteína 1 Similar a la Angiopoyetina , Proteínas Similares a la Angiopoyetina , Animales , Femenino , Humanos , Masculino , Ratones , Persona de Mediana Edad , Células Madre Neoplásicas , Niacinamida/uso terapéutico , SorafenibRESUMEN
Hepatocellular carcinoma (HCC) relies on angiogenesis for growth and metastasis. Leukocyte cell-derived chemotaxin 2 (LECT2) is a cytokine and preferentially expressed in the liver. Previous studies have found that LECT2 targets to both immune and tumor cells to suppress HCC development and vascular invasion. Although LECT2 did not affect HCC cells growth in vitro, it still suppressed HCC xenografts growth in immune-deficient mice, suggesting other cells such as stroma cells may also be targeted by LECT2. Here, we sought to determine the role of LECT2 in tumor angiogenesis in HCC patients. We found that LECT2 expression inhibited tumor growth via angiogenesis in the HCC xenograft model. Specifically, we demonstrated that recombinant human LECT2 protein selectively suppressed vascular endothelial growth factor (VEGF)165-induced endothelial cell proliferation, migration, and tube formation in vitro and in vivo. Mechanistically, LECT2 reduced VEGF receptor 2 tyrosine phosphorylation and its downstream extracellular signal-regulated kinase and AKT phosphorylation. Furthermore, LECT2 gene expression correlated negatively with angiogenesis in HCC patients. Taken together, our findings demonstrate that LECT2 inhibits VEGF165-induced HCC angiogenesis through directly binding to VEGFR2 and has broad applications in treating VEGF-mediated solid tumors.
Asunto(s)
Inhibidores de la Angiogénesis/administración & dosificación , Carcinoma Hepatocelular/tratamiento farmacológico , Péptidos y Proteínas de Señalización Intercelular/administración & dosificación , Neoplasias Hepáticas/tratamiento farmacológico , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Inhibidores de la Angiogénesis/farmacología , Animales , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Humanos , Péptidos y Proteínas de Señalización Intercelular/farmacología , Neoplasias Hepáticas/metabolismo , Ratones , Fosforilación/efectos de los fármacos , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/farmacología , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Paclitaxel is a standard-of-care chemotherapy for breast cancer, despite the increasing recognition of its poor effectiveness in the treatment of patients with advanced disease. Here, we report that adenovirus-type 5 E1A-mediated elevation of the miRNA-processing enzyme Dicer is sufficient to enhance paclitaxel sensitization and reduce cancer stem-like cell properties in this setting. Elevating Dicer expression increased levels of the AXL kinase targeting miRNA miR-494, thereby repressing AXL expression to increase paclitaxel sensitivity. We found that Dicer expression was regulated at the transcription level by E1A, through activation of an MAPK14/CEBPα pathway. Our findings define a mechanism of E1A-mediated chemosensitization for paclitaxel, which is based upon the suppression of breast cancer stem-like cells, with potential implications for the diagnosis and treatment of breast cancer patients. Cancer Res; 76(13); 3916-28. ©2016 AACR.
Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/tratamiento farmacológico , ARN Helicasas DEAD-box/metabolismo , Células Madre Neoplásicas/efectos de los fármacos , Paclitaxel/farmacología , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Ribonucleasa III/metabolismo , Adenoviridae/genética , Proteínas E1A de Adenovirus/metabolismo , Animales , Antineoplásicos Fitogénicos/farmacología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Femenino , Humanos , Ratones , Ratones Endogámicos NOD , Ratones SCID , MicroARNs/genética , Proteína Quinasa 14 Activada por Mitógenos/metabolismo , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto , Tirosina Quinasa del Receptor AxlRESUMEN
Therapy with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (EGFR-TKIs, such as gefitinib or erlotinib) significantly prolongs survival time for patients with tumors harboring an activated mutation on EGFR; however, up to 40% of lung cancer patients exhibit acquired resistance to EGFR-TKIs with an unknown mechanism. FOXO3a, a transcription factor of the forkhead family, triggers apoptosis, but the mechanistic details involved in EGFR-TKI resistance and cancer stemness remain largely unclear. Here, we observed that a high level of FOXO3a was correlated with EGFR mutation-independent EGFR-TKI sensitivity, the suppression of cancer stemness, and better progression-free survival in lung cancer patients. The suppression of FOXO3a obviously increased gefitinib resistance and enhanced the stem-like properties of lung cancer cells; consistent overexpression of FOXO3a in gefitinib-resistant lung cancer cells reduced these effects. Moreover, we identified that miR-155 targeted the 3'UTR of FOXO3a and was transcriptionally regulated by NF-κB, leading to repressed FOXO3a expression and increased gefitinib resistance, as well as enhanced cancer stemness of lung cancer in vitro and in vivo. Our findings indicate that FOXO3a is a significant factor in EGFR mutation-independent gefitinib resistance and the stemness of lung cancer, and suggest that targeting the NF-κB/miR-155/FOXO3a pathway has potential therapeutic value in lung cancer with the acquisition of resistance to EGFR-TKIs.
Asunto(s)
Receptores ErbB/metabolismo , Proteína Forkhead Box O3/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , FN-kappa B/metabolismo , Quinazolinas/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/administración & dosificación , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo/efectos de los fármacos , Resistencia a Antineoplásicos , Receptores ErbB/genética , Femenino , Gefitinib , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Mutación , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Inhibidores de Proteínas Quinasas/administración & dosificación , Resultado del Tratamiento , Células Tumorales CultivadasRESUMEN
Angiopoietin-like protein 1 (ANGPTL1) is a potent regulator of angiogenesis. Growing evidence suggests that ANGPTL family proteins not only target endothelial cells but also affect tumor cell behavior. In a screen of 102 patients with lung cancer, we found that ANGPTL1 expression was inversely correlated with invasion, lymph node metastasis, and poor clinical outcomes. ANGPTL1 suppressed the migratory, invasive, and metastatic capabilities of lung and breast cancer cell lines in vitro and reduced metastasis in mice injected with cancer cell lines overexpressing ANGPTL1. Ectopic expression of ANGPTL1 suppressed the epithelial-to-mesenchymal transition (EMT) by reducing the expression of the zinc-finger protein SLUG. A microRNA screen revealed that ANGPTL1 suppressed SLUG by inducing expression of miR-630 in an integrin α(1)ß(1)/FAK/ERK/SP1 pathway-dependent manner. These results demonstrate that ANGPTL1 represses lung cancer cell motility by abrogating the expression of the EMT mediator SLUG.
Asunto(s)
Adenocarcinoma/metabolismo , Angiopoyetinas/fisiología , Movimiento Celular , Neoplasias Pulmonares/metabolismo , Factores de Transcripción/metabolismo , Adenocarcinoma/mortalidad , Adenocarcinoma/secundario , Proteína 1 Similar a la Angiopoyetina , Proteínas Similares a la Angiopoyetina , Angiopoyetinas/metabolismo , Animales , Secuencia de Bases , Sitios de Unión , Línea Celular Tumoral , Regulación hacia Abajo , Transición Epitelial-Mesenquimal , Femenino , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Integrina alfa1beta1/metabolismo , Estimación de Kaplan-Meier , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Metástasis Linfática , Sistema de Señalización de MAP Quinasas , Ratones , Ratones SCID , MicroARNs/genética , MicroARNs/metabolismo , Trasplante de Neoplasias , Pronóstico , Transducción de Señal , Factores de Transcripción de la Familia Snail , Factores de Transcripción/genética , TranscriptomaRESUMEN
MicroRNAs (miRNAs) influence many biological processes, including cancer. They do so by posttranscriptionally repressing target mRNAs to which they have sequence complementarity. Although it has been postulated that miRNAs can regulate other miRNAs, this has never been shown experimentally to our knowledge. Here, we demonstrate that miR-107 negatively regulates the tumor suppressor miRNA let-7 via a direct interaction. miR-107 was found to be highly expressed in malignant tissue from patients with advanced breast cancer, and its expression was inversely correlated with let-7 expression in tumors and in cancer cell lines. Ectopic expression of miR-107 in human cancer cell lines led to destabilization of mature let-7, increased expression of let-7 targets, and increased malignant phenotypes. In contrast, depletion of endogenous miR-107 dramatically increased the stability of mature let-7 and led to downregulation of let-7 targets. Accordingly, miR-107 expression increased the tumorigenic and metastatic potential of a human breast cancer cell line in mice via inhibition of let-7 and upregulation of let-7 targets. By mutating individual sites within miR-107 and let-7, we found that miR-107 directly interacts with let-7 and that the internal loop of the let-7/miR-107 duplex is critical for repression of let-7 expression. Altogether, we have identified an oncogenic role for miR-107 and provide evidence of a transregulational interaction among miRNAs in human cancer development.