RESUMEN
Pancreatic ductal adenocarcinoma (PDAC) is notorious for its poor survival and resistance to conventional therapies. PI3K signaling is implicated in both disease initiation and progression, and specific inhibitors of selected PI3K p110 isoforms for managing solid tumors are emerging. We demonstrate that increased activation of PI3K signals cooperates with oncogenic Kras to promote aggressive PDAC in vivo. The p110γ isoform is overexpressed in tumor tissue and promotes carcinogenesis via canonical AKT signaling. Its selective blockade sensitizes tumor cells to gemcitabine in vitro, and genetic ablation of p110γ protects against Kras-induced tumorigenesis. Diet/obesity was identified as a crucial means of p110 subunit up-regulation, and in the setting of a high-fat diet, p110γ ablation failed to protect against tumor development, showing increased activation of pAKT and hepatic damage. These observations suggest that a careful and judicious approach should be considered when targeting p110γ for therapy, particularly in obese patients.
Asunto(s)
Carcinogénesis/genética , Carcinoma Ductal Pancreático/genética , Fosfatidilinositol 3-Quinasa Clase Ib/genética , Enfermedad del Hígado Graso no Alcohólico/patología , Obesidad/complicaciones , Neoplasias Pancreáticas/genética , Animales , Antimetabolitos Antineoplásicos/farmacología , Antimetabolitos Antineoplásicos/uso terapéutico , Carcinogénesis/efectos de los fármacos , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/patología , Fosfatidilinositol 3-Quinasa Clase Ia/genética , Fosfatidilinositol 3-Quinasa Clase Ib/metabolismo , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Desoxicitidina/uso terapéutico , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Ácidos Grasos Omega-6/efectos adversos , Femenino , Glucosa/metabolismo , Humanos , Metabolismo de los Lípidos , Hígado/patología , Masculino , Ratones Noqueados , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Obesidad/etiología , Obesidad/metabolismo , Páncreas/patología , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/patología , Inhibidores de las Quinasa Fosfoinosítidos-3/farmacología , Inhibidores de las Quinasa Fosfoinosítidos-3/uso terapéutico , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Regulación hacia Arriba , GemcitabinaRESUMEN
Pancreatic ductal adenocarcinoma (PDAC) has extensive stromal involvement and remains one of the cancers with the highest mortality rates. Activin A has been implicated in colon cancer and its stroma but its role in the stroma of PDAC has not been elucidated. Activin A expression in cancer and stroma was assessed in human PDAC tissue microarrays (TMA). Activin A expression in human TMA is significantly higher in cancer samples, with expression in stroma correlated with shorter survival. Cultured pancreatic stellate cells (PSC) were found to secrete high levels of activin A resulting in PDAC cell migration that is abolished by anti-activin A neutralizing antibody. KPC mice treated with anti-activin A neutralizing antibody were evaluated for tumors, lesions and metastases quantified by immunohistochemistry. KPC mice with increased tumor burden express high plasma activin A. Treating KPC mice with an activin A neutralizing antibody does not reduce primary tumor size but decreases tumor metastases. From these data we conclude that PDAC patients with high activin A expression in stroma have a worse prognosis. PSCs secrete activin A, promoting increased PDAC migration. Inhibition of activin A in mice decreased metastases. Hence, stroma-rich PDAC patients might benefit from activin A inhibition.
Asunto(s)
Activinas/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Activinas/sangre , Adenocarcinoma/sangre , Adenocarcinoma/genética , Adenocarcinoma/patología , Animales , Carcinoma Ductal Pancreático/sangre , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patología , Línea Celular Tumoral , Movimiento Celular , Modelos Animales de Enfermedad , Células Epiteliales/metabolismo , Células Epiteliales/patología , Epitelio/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Metástasis de la Neoplasia , Neoplasias Pancreáticas/sangre , Neoplasias Pancreáticas/genética , Células Estrelladas Pancreáticas/metabolismo , Células Estrelladas Pancreáticas/patología , Pronóstico , Células del Estroma/metabolismo , Análisis de Supervivencia , Carga Tumoral , Regulación hacia Arriba/genéticaRESUMEN
Colorectal cancer (CRC) is the second deadliest cancer in the US due to its propensity to metastasize. Stromal cells and especially cancer-associated fibroblasts (CAF) play a critical biophysical role in cancer progression, but the precise pro-metastatic mechanisms are not clear. Activin A, a TGF-ß family member, is a strong pro-metastatic cytokine in the context of CRC. Here, we assessed the link between biophysical forces and pro-metastatic signaling by testing the hypothesis that CAF-generated mechanical forces lead to activin A release and associated downstream effects. Consistent with our hypothesis, we first determined that stromal activin A secretion increased with increasing substrate stiffness. Then we found that stromally-secreted activin A induced ligand-dependent CRC epithelial cell migration and epithelial to mesenchymal transition (EMT). In addition, serum activin A levels are significantly increased in metastatic (stage IV) CRC patients (1.558 ng/ml versus 0.4179 ng/ml, p < 0.05). We propose that increased tumor microenvironment stiffness leads to stromal cell-mediated TGF-ß family signaling relying on the induction and utilization of activin A signaling.
Asunto(s)
Activinas/sangre , Fibroblastos Asociados al Cáncer , Neoplasias Colorrectales/patología , Transducción de Señal , Microambiente Tumoral , Anciano , Anciano de 80 o más Años , Cadherinas/metabolismo , Fibroblastos Asociados al Cáncer/citología , Fibroblastos Asociados al Cáncer/metabolismo , Estudios de Casos y Controles , Línea Celular Tumoral , Movimiento Celular , Neoplasias Colorrectales/metabolismo , Transición Epitelial-Mesenquimal/efectos de los fármacos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Estadificación de Neoplasias , Factores de Transcripción de la Familia Snail/metabolismo , Factor de Crecimiento Transformador beta/farmacologíaRESUMEN
BACKGROUND: Colorectal cancer remains a deadly cancer due to metastatic disease. To understand the molecular mechanisms of metastasis in colon cancer, we investigated whether the copper chaperone antioxidant-1 (Atox1) protein plays a role in this process. Recent findings indicate that Atox1 protein has transcription factor activities and plays a vital role in cell proliferation in cancer cells. However, the role of Atox1 in metastasis has not been examined. METHODS: Atox1 expression was determined by immunofluorescence in a tissue microarray generated from a spectrum of CRC patients. Subcellular fractionation of colon cancer cell lines SW480 and SW620 cells was used to examine the cellular location of Atox1 in the face of activin A, a cytokine that stimulates colon cancer metastasis. Atox1 expression was genetically manipulated and cellular migration measured through trans-well assay and proliferation measured by colony formation assays. RESULTS: Here we demonstrate that in patients with metastatic colon cancer, there is a significant increase in the expression of nuclear Atox1. Interestingly, the metastatic CRC cell line SW620 has increased nuclear localization of Atox1 compared to its related non-metastatic cell line SW480. Further, inhibition of endogenous Atox1 by siRNA in SW620 decreased colony formation and reactive oxygen species generation via decreased expression of Atox1 targets cyclin D1 and NADPH oxidase subunit p47 phox, respectively. Additionally, overexpression of nuclear-targeted but not copper binding domain-mutated Atox1 in SW480 cells increased colony formation and cell migration that was further augmented by activin A stimulation, a known enhancer of colon cancer metastasis. CONCLUSIONS: Our findings suggest that nuclear Atox1 might be a new therapeutic target as well as a new biomarker for metastatic colorectal cancer.
Asunto(s)
Activinas/metabolismo , Carcinoma , Movimiento Celular , Neoplasias del Colon , Proteínas Transportadoras de Cobre/fisiología , Chaperonas Moleculares/fisiología , Carcinoma/metabolismo , Carcinoma/patología , Línea Celular Tumoral , Proliferación Celular , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , HumanosRESUMEN
INTRODUCTION: Acute pancreatitis (AP) is a healthcare challenge with considerable mortality. Treatment is limited to supportive care, highlighting the need to investigate disease drivers and prognostic markers. Activin A is an established mediator of inflammatory responses, and its serum levels correlate with AP severity. We hypothesized that activin A is independent of body mass index (BMI) and is a targetable promoter of the AP inflammatory response. METHODS: We assessed whether BMI and serum activin A levels are independent markers to determine disease severity in a cohort of patients with AP. To evaluate activin A inhibition as a therapeutic, we used a cerulein-induced murine model of AP and treated mice with activin A-specific neutralizing antibody or immunoglobulin G control, both before and during the development of AP. We measured the production and release of activin A by pancreas and macrophage cell lines and observed the activation of macrophages after activin A treatment. RESULTS: BMI and activin A independently predicted severe AP in patients. Inhibiting activin A in AP mice reduced disease severity and local immune cell infiltration. Inflammatory stimulation led to activin A production and release by pancreas cells but not by macrophages. Macrophages were activated by activin A, suggesting activin A might promote inflammation in the pancreas in response to injury. DISCUSSION: Activin A provides a promising therapeutic target to interrupt the cycle of inflammation and tissue damage in AP progression. Moreover, assessing activin A and BMI in patients on hospital admission could provide important predictive measures for screening patients likely to develop severe disease.
Asunto(s)
Activinas/metabolismo , Antiinflamatorios/farmacología , Páncreas/patología , Pancreatitis/diagnóstico , Índice de Severidad de la Enfermedad , Activinas/antagonistas & inhibidores , Activinas/sangre , Activinas/inmunología , Animales , Antiinflamatorios/uso terapéutico , Biomarcadores/sangre , Biomarcadores/metabolismo , Índice de Masa Corporal , Línea Celular , Ceruletida/administración & dosificación , Ceruletida/toxicidad , Estudios de Cohortes , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Femenino , Humanos , Activación de Macrófagos/inmunología , Macrófagos , Ratones , Páncreas/efectos de los fármacos , Páncreas/inmunología , Pancreatitis/sangre , Pancreatitis/tratamiento farmacológico , Pancreatitis/inmunología , Admisión del Paciente , Valor Predictivo de las PruebasRESUMEN
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
RESUMEN
Current therapies for pancreatic ductal adenocarcinoma (PDAC) only modestly impact survival and can be highly toxic. A greater understanding of the molecules regulating this disease is critical for identifying new drug targets and developing more effective therapies. The L6 family of proteins are known to be positive regulators of tumor growth and metastasis among various cancers. However, little is known about the L6 family member TM4SF18. We investigated the expression and localization of the TM4SF18 protein in normal human pancreas and in PDAC tissue. Utilizing immunohistochemistry (IHC) and western blot analysis, our studies for the first time demonstrate that TM4SF18 is highly expressed in PDAC tumor epithelium. Furthermore, we identified TM4SF18 to be expressed in normal acinar tissue and weakly expressed in normal ducts. Although there is minimal expression in normal ducts, we observed increased TM4SF18 levels in preneoplastic ducts and tumor epithelium. To investigate a functional role of TM4SF18 in PDAC we developed stably-expressing inducible shRNA pancreatic cancer cell lines. Knockdown of the TM4SF18 protein led to a significant decrease in Capan-1 cell growth as measured by the MTT assay, demonstrating this molecule to be a novel regulator of PDAC. Uniquely there is no ortholog of the TM4SF18 gene in mouse or rat prompting us to seek other in vivo experimental models. Using IHC and western blot analysis, expression of TM4SF18 was confirmed in the porcine PDAC model, thus we establish an alternative model to investigate this gene. TM4SF18 represents a promising novel biomarker and therapeutic target for pancreatic cancer.
Asunto(s)
Carcinoma Ductal Pancreático/metabolismo , Neoplasias Pancreáticas/metabolismo , Tetraspaninas/metabolismo , Células Acinares/metabolismo , Células Acinares/patología , Animales , Animales Modificados Genéticamente , Carcinoma Ductal Pancreático/patología , Línea Celular Tumoral , Movimiento Celular/fisiología , Supervivencia Celular/fisiología , Modelos Animales de Enfermedad , Epitelio/metabolismo , Epitelio/patología , Femenino , Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Conductos Pancreáticos/metabolismo , Conductos Pancreáticos/patología , Neoplasias Pancreáticas/patología , Sus scrofaRESUMEN
The pancreatic acinar-enriched miR-216a, miR-216b and miR-217 are encoded within the miR217HG. These miRNAs have been purported to play a tumor suppressive role as their expression is reduced in both human and mouse pancreatic ductal adenocarcinoma (PDAC). To examine this possibility, we generated individual, germline knockout (KO) mice of miR-216a, miR-216b or miR-217. Unlike our previous study showing germline deletion of the miR217HG was embryonic lethal, CRISPR-Cas9 deleted portions of the 5' seed region of the miRNAs produced live births. To investigate possible phenotypes during pancreatic acinar ductal metaplasia (ADM), pancreatic acini from wild type and KO mice were plated on collagen and allowed to transdifferentiate over 4 days. Acini from each of the three miRNA KO mice produced greater numbers of ducts compared to controls. Evaluation of the gene expression during in vitro ADM demonstrated an increase in Krt19 and a reduction in acinar genes (Carboxypeptidase A1, Amylase2a) on day 4 of the transdifferentiation. Recovery was delayed for the miR-216a and miR-216b KOs following caerulein-induced acute pancreatitis. Also predominate in the caerulein treated miR-216a and miR-216b KO mice was the presence of pancreatic duct glands (PDGs). To further establish a phenotype, miRNA KO mice were crossed with EL-KRASG12D (EK) mice and followed up to 13 months of age. While all mice developed severe dysplasia and cystic papillary neoplasms, there existed no apparent phenotypic difference in the miRNA KO/EK mice compared to EK mice. Our data does not support a tumor suppressor role for miR-216a, miR-216b or miR-217 in PDAC and emphasizes the need for phenotypic evaluation of miRNAs in complex in vivo models beyond that performed using cell culture.
Asunto(s)
Células Acinares/patología , Carcinoma Ductal Pancreático/genética , Transformación Celular Neoplásica/genética , MicroARNs/genética , Conductos Pancreáticos/patología , Neoplasias Pancreáticas/genética , Animales , Carcinoma in Situ/genética , Carcinoma in Situ/patología , Carcinoma Ductal Pancreático/patología , Transdiferenciación Celular/genética , Transformación Celular Neoplásica/patología , Expresión Génica/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neoplasias Pancreáticas/patología , Pancreatitis/genética , Pancreatitis/patología , Transducción de Señal/genética , Neoplasias PancreáticasRESUMEN
Pancreatic cancer remains a daunting foe despite a vast number of accumulating molecular analyses regarding the mutation and expression status of a variety of genes. Indeed, most pancreatic cancer cases uniformly present with a mutation in the KRAS allele leading to enhanced RAS activation. Yet our understanding of the many epigenetic/environmental factors contributing to disease incidence and progression is waning. Epidemiologic data suggest that diet may be a key factor in pancreatic cancer development and potentially a means of chemoprevention at earlier stages. While diets high in ω3 fatty acids are typically associated with tumor suppression, diets high in ω6 fatty acids have been linked to increased tumor development. Thus, to better understand the contribution of these polyunsaturated fatty acids to pancreatic carcinogenesis, we modeled early stage disease by targeting mutant KRAS to the exocrine pancreas and administered diets rich in these fatty acids to assess tumor formation and altered cell-signaling pathways. We discovered that, consistent with previous reports, the ω3-enriched diet led to reduced lesion penetrance via repression of proliferation associated with reduced phosphorylated AKT (pAKT), whereas the ω6-enriched diet accelerated tumor formation. These data provide a plausible mechanism underlying previously observed effects of fatty acids and suggest that administration of ω3 fatty acids can reduce the pro-survival, pro-growth functions of pAKT. Indeed, counseling subjects at risk to increase their intake of foods containing higher amounts of ω3 fatty acids could aid in the prevention of pancreatic cancer.
Asunto(s)
Anticarcinógenos/administración & dosificación , Transformación Celular Neoplásica/metabolismo , Dieta , Ácidos Grasos Omega-3/administración & dosificación , Neoplasias Experimentales/prevención & control , Conductos Pancreáticos/enzimología , Neoplasias Pancreáticas/prevención & control , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Animales , Apoptosis , Línea Celular , Proliferación Celular , Supervivencia Celular , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Dieta/efectos adversos , Regulación hacia Abajo , Humanos , Ratones Transgénicos , Mutación , Neoplasias Experimentales/enzimología , Neoplasias Experimentales/genética , Neoplasias Experimentales/patología , Conductos Pancreáticos/patología , Neoplasias Pancreáticas/enzimología , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Fosforilación , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismoRESUMEN
Advanced colorectal cancer (CRC) remains a critical health care challenge worldwide. Various TGF-ß superfamily members are important in colorectal cancer metastasis, but their signaling effects and predictive value have only been assessed in isolation. Here, we examine cross-regulation and combined functions of the two most prominent TGF-ß superfamily members activin and TGF-ß in advanced colorectal cancer. In two clinical cohorts we observed by immune-based assay that combined serum and tissue activin and TGF-ß ligand levels predicts outcome in CRC patients and is superior to single ligand assessment. While TGF-ß growth suppression is independent of activin, TGF-ß treatment leads to increased activin secretion in colon cancer cells and TGF-ß induced cellular migration is dependent on activin, indicating pathway cross-regulation and functional interaction in vitro. mRNA expression of activin and TGF-ß pathway members were queried in silico using the TCGA data set. Coordinated ligand and receptor expression is common in solid tumors for activin and TGF-ß pathway members. In conclusion, activin and TGF-ß are strongly connected signaling pathways that are important in advanced CRC. Assessing activin and TGF-ß signaling as a unit yields important insights applicable to future diagnostic and therapeutic interventions.
Asunto(s)
Activinas/genética , Activinas/metabolismo , Neoplasias Colorrectales/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Activinas/sangre , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/patología , Femenino , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Humanos , Masculino , Estadificación de Neoplasias , Pronóstico , Transducción de Señal , Análisis de Supervivencia , Factor de Crecimiento Transformador beta/sangre , Regulación hacia ArribaRESUMEN
Honey bees move through a series of in-hive tasks (e.g., "nursing") to outside tasks (e.g., "foraging") that are coincident with physiological changes and higher levels of metabolic activity. Social context can cause worker bees to speed up or slow down this process, and foragers may revert back to their earlier in-hive tasks accompanied by reversion to earlier physiological states. To investigate the effects of flight, behavioral state and age on gene expression, we used whole-genome microarrays and real-time PCR. Brain tissue and flight muscle exhibited different patterns of expression during behavioral transitions, with expression patterns in the brain reflecting both age and behavior, and expression patterns in flight muscle being primarily determined by age. Our data suggest that the transition from behaviors requiring little to no flight (nursing) to those requiring prolonged flight bouts (foraging), rather than the amount of previous flight per se, has a major effect on gene expression. Following behavioral reversion there was a partial reversion in gene expression but some aspects of forager expression patterns, such as those for genes involved in immune function, remained. Combined with our real-time PCR data, these data suggest an epigenetic control and energy balance role in honey bee functional senescence.