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1.
Ann Surg Oncol ; 31(2): 1252-1263, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38006531

RESUMEN

BACKGROUND: Discontinuation of the Codman 3000 pump in 2018 left no Food and Drug Administration (FDA)-approved hepatic artery infusion (HAI) device for unresectable colorectal liver metastases (uCLM) and intrahepatic cholangiocarcinoma (uIHC). Historically, HAI has been performed at academic medical centers in large metropolitan areas, which are often inaccessible to rural patients. Consequently, feasibility of dissemination of HAI to rural populations is unknown. PATIENTS AND METHODS: Under an FDA investigational device exemption, we opened the only HAI program in Kentucky and enrolled patients with uCLM and uIHC in a phase I clinical trial. The trial examined the safety of the hybrid Codman catheter/Medtronic SynchroMed II pump (hCMP) combination, defined as successful completion of one cycle of HAI chemotherapy. Rural feasibility was assessed by number of missed pump fills appointments. RESULTS: A total of 21 patients (n = 17 uCLM, n = 4 uIHC) underwent hCMP implantation before accrual was stopped early owing to FDA approval of the Intera 3000 pump. 20/21 (95%) patients met the primary safety endpoint. Serious adverse events (AEs) included a grade 5 coronavirus disease 2019 (COVID-19) infection (n = 1) and a grade 3 catheter erosion into the bowel (n = 1). Biliary sclerosis developed in two patients (9.5%). Median distance to infusion center was 47.6 miles (2-138 miles), and 62% were from Appalachia, yet there were no missed pump fill appointments. The 2-year overall survival was 82.4% (uCLM) and 50% (uIHC). CONCLUSIONS: The hCMP device had an acceptable safety profile. Despite the complexity of starting a new HAI program, early results showed feasibility for HAI delivery in a rural catchment area and comparable outcomes to larger urban-based HAI centers.


Asunto(s)
Neoplasias de los Conductos Biliares , Neoplasias Colorrectales , Neoplasias Hepáticas , Dispositivos de Acceso Vascular , Humanos , Neoplasias Colorrectales/patología , Arteria Hepática/patología , Estudios de Factibilidad , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Hepáticas/secundario , Infusiones Intraarteriales , Conductos Biliares Intrahepáticos/patología , Neoplasias de los Conductos Biliares/tratamiento farmacológico , Neoplasias de los Conductos Biliares/etiología
2.
FASEB J ; 35(5): e21371, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33811694

RESUMEN

Studies demonstrate a role for neurotensin (NT) in obesity and related comorbidities. Bile acid (BA) homeostasis alterations are associated with obesity. We determined the effect of NT on BA metabolism in obese and non-obese conditions. Plasma and fecal BA profiles were analyzed by LC-MS/MS in male and female NT+/+ and NT-/- mice fed low-fat (LFD) or high-fat diet (HFD) for 6 weeks (early stage of obesity) or greater than 20 weeks (late stage of obesity). The nuclear farnesoid X receptor (FXR) and BA transporter mRNA expression were assessed in ileum, mouse enteroids, and human cell lines. HFD decreased plasma primary and secondary BAs in NT+/+ mice; HFD-induced decrease of plasma BAs was improved in NT-deficient mice. In NT+/+ mice, HFD inhibited ileal FXR and BA transporter expression; HFD-decreased expression of FXR and BA transporters was prevented in NT-/- mice. Compared with LFD-fed NT+/+ mice, LFD-fed NT-/- mice had relatively lower levels of ileal FXR and BA transporter expression. Moreover, NT stimulates the expression of FXR and BA transporters in Caco-2 cells; however, stimulated expression of BA transporters was attenuated in NT-/- enteroids. Therefore, we demonstrate that HFD disrupts the BA metabolism and ileal FXR and BA transporter axis which are improved in the absence of NT, suggesting that NT contributes to HFD-induced disruption of BA metabolism and plays an inhibitory role in the regulation of ileal FXR and BA transporter signaling under obese conditions. Conversely, NT positively regulates the expression of ileal FXR and BA transporters under non-obese conditions. Therefore, NT plays a dual role in obese and non-obese conditions, suggesting possible therapeutic strategies for obesity control.


Asunto(s)
Ácidos y Sales Biliares/metabolismo , Intestinos/fisiología , Neurotensina/fisiología , Nutrientes/metabolismo , Obesidad/fisiopatología , Receptores Citoplasmáticos y Nucleares/metabolismo , Animales , Células CACO-2 , Dieta Alta en Grasa , Femenino , Humanos , Masculino , Ratones
3.
J Neurooncol ; 156(1): 153-161, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34820776

RESUMEN

BACKGROUND: Hematological adverse events (HAEs) are common during treatment for glioblastoma (GBM), usually associated with temozolomide (TMZ). Their clinical value is uncertain, as few investigations have focused on outcomes for HAEs during GBM treatment. METHODS: We combined data from two randomized clinical trials, RTOG 0525 and RTOG 0825, to analyze HAEs during treatment for GBM. We investigated differences between chemoradiation and adjuvant therapy, and by regimen received during adjuvant treatment. RESULTS: 1454 patients participated in these trials, of which 1154 (79.4%) developed HAEs. During chemoradiation, 44.4% of patients developed HAEs (54% involving more than one cell line), and were most commonly lymphopenia (50.6%), and thrombocytopenia (47.5%). During adjuvant treatment, 45% of patients presented HAEs (78.6% involving more than one cell line), and were more commonly leukopenia (62.7%), and thrombocytopenia (62.3%). Median overall survival (OS) and progression free survival (PFS) were longer in patients with HAEs (OS 19.4 months and PFS 9.9 months) compared to those with other or no adverse events (OS 14.1 months and PFS 5.9 months). There was no significant difference in survival between grade 1 and/or 2 versus grade 3 and/or 4 HAEs. History of HAEs during chemoradiation was a protective factor for presentation of HAEs during adjuvant therapy. CONCLUSION: HAEs are common during GBM treatment, and often involve more than one cell line (more likely during adjuvant therapy). HAEs may be associated with prolonged OS and PFS, particularly during adjuvant therapy. HAEs during chemoradiation was a protective factor for HAEs during adjuvant therapy.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Antineoplásicos Alquilantes/efectos adversos , Neoplasias Encefálicas/tratamiento farmacológico , Glioblastoma/tratamiento farmacológico , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Temozolomida/efectos adversos , Trombocitopenia/inducido químicamente
4.
Nature ; 533(7603): 411-5, 2016 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-27193687

RESUMEN

Obesity and its associated comorbidities (for example, diabetes mellitus and hepatic steatosis) contribute to approximately 2.5 million deaths annually and are among the most prevalent and challenging conditions confronting the medical profession. Neurotensin (NT; also known as NTS), a 13-amino-acid peptide predominantly localized in specialized enteroendocrine cells of the small intestine and released by fat ingestion, facilitates fatty acid translocation in rat intestine, and stimulates the growth of various cancers. The effects of NT are mediated through three known NT receptors (NTR1, 2 and 3; also known as NTSR1, 2, and NTSR3, respectively). Increased fasting plasma levels of pro-NT (a stable NT precursor fragment produced in equimolar amounts relative to NT) are associated with increased risk of diabetes, cardiovascular disease and mortality; however, a role for NT as a causative factor in these diseases is unknown. Here we show that NT-deficient mice demonstrate significantly reduced intestinal fat absorption and are protected from obesity, hepatic steatosis and insulin resistance associated with high fat consumption. We further demonstrate that NT attenuates the activation of AMP-activated protein kinase (AMPK) and stimulates fatty acid absorption in mice and in cultured intestinal cells, and that this occurs through a mechanism involving NTR1 and NTR3 (also known as sortilin). Consistent with the findings in mice, expression of NT in Drosophila midgut enteroendocrine cells results in increased lipid accumulation in the midgut, fat body, and oenocytes (specialized hepatocyte-like cells) and decreased AMPK activation. Remarkably, in humans, we show that both obese and insulin-resistant subjects have elevated plasma concentrations of pro-NT, and in longitudinal studies among non-obese subjects, high levels of pro-NT denote a doubling of the risk of developing obesity later in life. Our findings directly link NT with increased fat absorption and obesity and suggest that NT may provide a prognostic marker of future obesity and a potential target for prevention and treatment.


Asunto(s)
Dieta Alta en Grasa/efectos adversos , Neurotensina/metabolismo , Obesidad/inducido químicamente , Obesidad/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Animales , Línea Celular , Modelos Animales de Enfermedad , Drosophila melanogaster/citología , Drosophila melanogaster/enzimología , Drosophila melanogaster/metabolismo , Células Enteroendocrinas/metabolismo , Activación Enzimática , Cuerpo Adiposo/metabolismo , Ácidos Grasos/metabolismo , Hígado Graso/metabolismo , Hígado Graso/prevención & control , Femenino , Humanos , Resistencia a la Insulina/fisiología , Mucosa Intestinal/metabolismo , Intestinos/citología , Metabolismo de los Lípidos , Masculino , Ratones , Persona de Mediana Edad , Neurotensina/sangre , Neurotensina/deficiencia , Neurotensina/genética , Obesidad/sangre , Obesidad/prevención & control , Precursores de Proteínas/sangre , Precursores de Proteínas/metabolismo
5.
Int J Mol Sci ; 23(12)2022 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-35742953

RESUMEN

Altered lipid metabolism is a potential target for therapeutic intervention in cancer. Overexpression of Fatty Acid Synthase (FASN) correlates with poor prognosis in colorectal cancer (CRC). While multiple studies show that upregulation of lipogenesis is critically important for CRC progression, the contribution of FASN to CRC initiation is poorly understood. We utilize a C57BL/6-Apc/Villin-Cre mouse model with knockout of FASN in intestinal epithelial cells to show that the heterozygous deletion of FASN increases mouse survival and decreases the number of intestinal adenomas. Using RNA-Seq and gene set enrichment analysis, we demonstrate that a decrease in FASN expression is associated with inhibition of pathways involved in cellular proliferation, energy production, and CRC progression. Metabolic and reverse phase protein array analyses demonstrate consistent changes in alteration of metabolic pathways involved in both anabolism and energy production. Downregulation of FASN expression reduces the levels of metabolites within glycolysis and tricarboxylic acid cycle with the most significant reduction in the level of citrate, a master metabolite, which enhances ATP production and fuels anabolic pathways. In summary, we demonstrate the critical importance of FASN during CRC initiation. These findings suggest that targeting FASN is a potential therapeutic approach for early stages of CRC or as a preventive strategy for this disease.


Asunto(s)
Adenoma , Neoplasias Colorrectales , Adenoma/genética , Animales , Línea Celular Tumoral , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Modelos Animales de Enfermedad , Regulación hacia Abajo/genética , Acido Graso Sintasa Tipo I/genética , Acido Graso Sintasa Tipo I/metabolismo , Ácido Graso Sintasas/genética , Ácido Graso Sintasas/metabolismo , Ratones , Ratones Endogámicos C57BL , Transcriptoma
6.
FASEB J ; 34(6): 8596-8610, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32359121

RESUMEN

We previously reported that high levels of plasma neurotensin (NT), a gut hormone released from enteroendocrine cells of the small bowel, contribute to obesity and comorbid conditions. Gut microbiota has been implicated in the obesity development. Paneth cells are critical in maintaining gut microbiota composition and homeostasis by releasing antimicrobial proteins including α-defensins. The purpose of our current study was to determine the possible role of NT in gut microbiota composition and α-defensin gene expression associated with obesity. Here we show that the ratio of Firmicutes/Bacteroidetes (F/B ratio) and intestinal proinflammatory cytokines is significantly increased in NT+/+ mice fed with a high-fat diet (HFD) which were improved in NT-deficient mice. HFD disrupted the intestinal Mmp7/α-defensin axis, which was completely prevented in NT-/- mice. In addition, NT treatment inhibited DEFA5 expression and concurrent NF-κB activity, which was blocked by a pan PKC inhibitor (Gö6983) or an inhibitor for atypical PKCs (CRT0066854). More importantly, the shRNA-mediated knockdown of atypical PKCτ reversed NT-attenuated DEFA5 expression and increased NF-κB activity. NT contributes to the HFD-induced disruption of gut microbiota composition and α-defensin expression. PKCτ/λ plays a central role in NT-mediated α-defensin gene expression which might be mediated through the inhibition of NF-κB signaling pathways in Paneth cells.


Asunto(s)
Disbiosis/metabolismo , Inflamación/metabolismo , Metaloproteinasa 7 de la Matriz/metabolismo , Neurotensina/metabolismo , alfa-Defensinas/metabolismo , Tejido Adiposo/metabolismo , Animales , Citocinas/metabolismo , Dieta Alta en Grasa/efectos adversos , Disbiosis/patología , Microbioma Gastrointestinal/fisiología , Inflamación/patología , Resistencia a la Insulina/fisiología , Intestinos/patología , Masculino , Ratones , Ratones Obesos , FN-kappa B/metabolismo , Obesidad/metabolismo , Células de Paneth/metabolismo , Transducción de Señal/fisiología
7.
J Biol Chem ; 294(18): 7516-7527, 2019 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-30885944

RESUMEN

It is generally accepted that alterations in metabolism are critical for the metastatic process; however, the mechanisms by which these metabolic changes are controlled by the major drivers of the metastatic process remain elusive. Here, we found that S100 calcium-binding protein A4 (S100A4), a major metastasis-promoting protein, confers metabolic plasticity to drive tumor invasion and metastasis of non-small cell lung cancer cells. Investigating how S100A4 regulates metabolism, we found that S100A4 depletion decreases oxygen consumption rates, mitochondrial activity, and ATP production and also shifts cell metabolism to higher glycolytic activity. We further identified that the 49-kDa mitochondrial complex I subunit NADH dehydrogenase (ubiquinone) Fe-S protein 2 (NDUFS2) is regulated in an S100A4-dependent manner and that S100A4 and NDUFS2 exhibit co-occurrence at significant levels in various cancer types as determined by database-driven analysis of genomes in clinical samples using cBioPortal for Cancer Genomics. Importantly, we noted that S100A4 or NDUFS2 silencing inhibits mitochondrial complex I activity, reduces cellular ATP level, decreases invasive capacity in three-dimensional growth, and dramatically decreases metastasis rates as well as tumor growth in vivo Finally, we provide evidence that cells depleted in S100A4 or NDUFS2 shift their metabolism toward glycolysis by up-regulating hexokinase expression and that suppressing S100A4 signaling sensitizes lung cancer cells to glycolysis inhibition. Our findings uncover a novel S100A4 function and highlight its importance in controlling NDUFS2 expression to regulate the plasticity of mitochondrial metabolism and thereby promote the invasive and metastatic capacity in lung cancer.


Asunto(s)
Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , NADH Deshidrogenasa/metabolismo , Invasividad Neoplásica , Proteína de Unión al Calcio S100A4/metabolismo , Regulación hacia Arriba , Adenosina Trifosfato/biosíntesis , Línea Celular Tumoral , Silenciador del Gen , Glucólisis , Humanos , NADH Deshidrogenasa/genética , Metástasis de la Neoplasia , Transducción de Señal
8.
Pharm Stat ; 19(3): 214-229, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31749311

RESUMEN

Recently, molecularly targeted agents and immunotherapy have been advanced for the treatment of relapse or refractory cancer patients, where disease progression-free survival or event-free survival is often a primary endpoint for the trial design. However, methods to evaluate two-stage single-arm phase II trials with a time-to-event endpoint are currently processed under an exponential distribution, which limits application of real trial designs. In this paper, we developed an optimal two-stage design, which is applied to the four commonly used parametric survival distributions. The proposed method has advantages compared with existing methods in that the choice of underlying survival model is more flexible and the power of the study is more adequately addressed. Therefore, the proposed two-stage design can be routinely used for single-arm phase II trial designs with a time-to-event endpoint as a complement to the commonly used Simon's two-stage design for the binary outcome.


Asunto(s)
Ensayos Clínicos Fase II como Asunto , Determinación de Punto Final , Proyectos de Investigación , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/terapia , Ensayos Clínicos Fase II como Asunto/estadística & datos numéricos , Interpretación Estadística de Datos , Determinación de Punto Final/estadística & datos numéricos , Humanos , Inmunoterapia , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/terapia , Modelos Estadísticos , Supervivencia sin Progresión , Proyectos de Investigación/estadística & datos numéricos , Análisis de Supervivencia , Factores de Tiempo
10.
Pharm Stat ; 18(2): 212-222, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30458583

RESUMEN

Molecularly targeted, genomic-driven, and immunotherapy-based clinical trials continue to be advanced for the treatment of relapse or refractory cancer patients, where the growth modulation index (GMI) is often considered a primary endpoint of treatment efficacy. However, there little literature is available that considers the trial design with GMI as the primary endpoint. In this article, we derived a sample size formula for the score test under a log-linear model of the GMI. Study designs using the derived sample size formula are illustrated under a bivariate exponential model, the Weibull frailty model, and the generalized treatment effect size. The proposed designs provide sound statistical methods for a single-arm phase II trial with GMI as the primary endpoint.


Asunto(s)
Ensayos Clínicos Fase II como Asunto/métodos , Modelos Estadísticos , Neoplasias/terapia , Proyectos de Investigación , Interpretación Estadística de Datos , Determinación de Punto Final , Humanos , Inmunoterapia/métodos , Terapia Molecular Dirigida , Tamaño de la Muestra , Resultado del Tratamiento
11.
Nucleic Acids Res ; 44(20): e151, 2016 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-27471031

RESUMEN

The advanced medium-throughput NanoString nCounter technology has been increasingly used for mRNA or miRNA differential expression (DE) studies due to its advantages including direct measurement of molecule expression levels without amplification, digital readout and superior applicability to formalin fixed paraffin embedded samples. However, the analysis of nCounter data is hampered because most methods developed are based on t-tests, which do not fit the count data generated by the NanoString nCounter system. Furthermore, data normalization procedures of current methods are either not suitable for counts or not specific for NanoString nCounter data. We develop a novel DE detection method based on NanoString nCounter data. The method, named NanoStringDiff, considers a generalized linear model of the negative binomial family to characterize count data and allows for multifactor design. Data normalization is incorporated in the model framework through data normalization parameters, which are estimated from positive controls, negative controls and housekeeping genes embedded in the nCounter system. We propose an empirical Bayes shrinkage approach to estimate the dispersion parameter in the model and a likelihood ratio test to identify differentially expressed genes. Simulations and real data analysis demonstrate that the proposed method performs better than existing methods.


Asunto(s)
Biología Computacional/métodos , Perfilación de la Expresión Génica/métodos , MicroARNs/genética , Modelos Estadísticos , ARN Mensajero/genética , Algoritmos , Simulación por Computador , Conjuntos de Datos como Asunto , Regulación de la Expresión Génica , Reproducibilidad de los Resultados
12.
Biochim Biophys Acta ; 1852(10 Pt A): 2013-23, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26187040

RESUMEN

A common feature of inflammatory bowel disease (IBD) is the loss of intestinal epithelial barrier function due to excessive apoptosis of intestinal epithelial cells (IECs). However, the molecular mechanism underlying increased IEC apoptosis remains unclear. Here, we investigated the role of PHLPP, a novel family of protein phosphatases, in regulating inflammation-induced IEC apoptosis in mouse models of colitis. Both Phlpp1 and Phlpp2 genes were deleted in mice. Compared with wild-type mice, PHLPP double knockout (DKO) mice were protected from colitis induced by DSS as demonstrated by lower histopathological scores, and this reduced susceptibility to colitis was associated with decreased apoptosis and increased Akt activity in IECs in vivo. In addition, epithelial organoids derived from PHLPP DKO mice were more resistant to inflammation-induced apoptosis while inhibition of Akt activity abolished the protective effect of PHLPP-loss. Furthermore, we found that PHLPP expression was significantly reduced in IECs following the induction of colitis by DSS and in human IBD patient samples. This inflammation-induced downregulation of PHLPP was partially blocked by treating cells with a proteasome inhibitor. Taken together, our results indicated that proteasome-mediated degradation of PHLPP at the onset of inflammation plays an important role in protecting IEC injury by inhibiting apoptosis.

13.
J Biol Chem ; 289(38): 26021-26037, 2014 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-25086043

RESUMEN

Autophagy is a tightly regulated lysosomal degradation pathway for maintaining cellular homeostasis and responding to stresses. Beclin 1 and its interacting proteins, including the class III phosphatidylinositol-3 kinase Vps34, play crucial roles in autophagy regulation in mammals. We identified nuclear receptor binding factor 2 (Nrbf2) as a Beclin 1-interacting protein from Becn1(-/-);Becn1-EGFP/+ mouse liver and brain. We also found that Nrbf2-Beclin 1 interaction required the N terminus of Nrbf2. We next used the human retinal pigment epithelial cell line RPE-1 as a model system and showed that transiently knocking down Nrbf2 by siRNA increased autophagic flux under both nutrient-rich and starvation conditions. To investigate the mechanism by which Nrbf2 regulates autophagy, we demonstrated that Nrbf2 interacted and colocalized with Atg14L, suggesting that Nrbf2 is a component of the Atg14L-containing Beclin 1-Vps34 complex. Moreover, ectopically expressed Nrbf2 formed cytosolic puncta that were positive for isolation membrane markers. These results suggest that Nrbf2 is involved in autophagosome biogenesis. Furthermore, we showed that Nrbf2 deficiency led to increased intracellular phosphatidylinositol-3 phosphate levels and diminished Atg14L-Vps34/Vps15 interactions, suggesting that Nrbf2-mediated Atg14L-Vps34/Vps15 interactions likely inhibit Vps34 activity. Therefore, we propose that Nrbf2 may interact with the Atg14L-containing Beclin 1-Vps34 protein complex to modulate protein-protein interactions within the complex, leading to suppression of Vps34 activity, autophagosome biogenesis, and autophagic flux. This work reveals a novel aspect of the intricate mechanism for the Beclin 1-Vps34 protein-protein interaction network to achieve precise control of autophagy.


Asunto(s)
Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Proteínas Reguladoras de la Apoptosis/metabolismo , Autofagia , Fosfatidilinositol 3-Quinasas Clase III/metabolismo , Proteínas de la Membrana/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Transactivadores/fisiología , Secuencia de Aminoácidos , Proteínas Relacionadas con la Autofagia , Beclina-1 , Proteínas Fluorescentes Verdes/biosíntesis , Células Hep G2 , Humanos , Datos de Secuencia Molecular , Complejos Multiproteicos/metabolismo , Fagosomas/metabolismo , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Mapas de Interacción de Proteínas , Transporte de Proteínas , Proteínas Recombinantes de Fusión/biosíntesis , Transactivadores/química
14.
Breast Cancer Res ; 17: 25, 2015 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-25849745

RESUMEN

INTRODUCTION: Triple-negative breast cancer (TNBC) is an aggressive form of breast cancer with no effective targeted therapy. Inducible nitric oxide synthase (iNOS) is associated with poor survival in patients with breast cancer by increasing tumor aggressiveness. This work aimed to investigate the potential of iNOS inhibitors as a targeted therapy for TNBC. We hypothesized that inhibition of endogenous iNOS would decrease TNBC aggressiveness by reducing tumor initiation and metastasis through modulation of epithelial-mesenchymal transition (EMT)-inducing factors. METHODS: iNOS protein levels were determined in 83 human TNBC tissues and correlated with clinical outcome. Proliferation, mammosphere-forming efficiency, migration, and EMT transcription factors were assessed in vitro after iNOS inhibition. Endogenous iNOS targeting was evaluated as a potential therapy in TNBC mouse models. RESULTS: High endogenous iNOS expression was associated with worse prognosis in patients with TNBC by gene expression as well as immunohistochemical analysis. Selective iNOS (1400 W) and pan-NOS (L-NMMA and L-NAME) inhibitors diminished cell proliferation, cancer stem cell self-renewal, and cell migration in vitro, together with inhibition of EMT transcription factors (Snail, Slug, Twist1, and Zeb1). Impairment of hypoxia-inducible factor 1α, endoplasmic reticulum stress (IRE1α/XBP1), and the crosstalk between activating transcription factor 3/activating transcription factor 4 and transforming growth factor ß was observed. iNOS inhibition significantly reduced tumor growth, the number of lung metastases, tumor initiation, and self-renewal. CONCLUSIONS: Considering the effectiveness of L-NMMA in decreasing tumor growth and enhancing survival rate in TNBC, we propose a targeted therapeutic clinical trial by re-purposing the pan-NOS inhibitor L-NMMA, which has been extensively investigated for cardiogenic shock as an anti-cancer therapeutic.


Asunto(s)
Antineoplásicos/farmacología , Inhibidores Enzimáticos/farmacología , Óxido Nítrico Sintasa de Tipo II/antagonistas & inhibidores , Neoplasias de la Mama Triple Negativas/metabolismo , Factor de Transcripción Activador 3/metabolismo , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Movimiento Celular/genética , Proliferación Celular/efectos de los fármacos , Transformación Celular Neoplásica/efectos de los fármacos , Transformación Celular Neoplásica/genética , Modelos Animales de Enfermedad , Estrés del Retículo Endoplásmico , Transición Epitelial-Mesenquimal/genética , Femenino , Expresión Génica , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Neoplasias Pulmonares/secundario , Ratones , Terapia Molecular Dirigida , Invasividad Neoplásica , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/metabolismo , Pronóstico , Factor de Crecimiento Transformador beta/metabolismo , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/mortalidad , Neoplasias de la Mama Triple Negativas/patología , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
15.
Int J Cancer ; 136(6): 1475-81, 2015 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-25098665

RESUMEN

Wnt/ß-catenin signaling plays a pivotal role in regulating cell growth and differentiation by activation of the ß-catenin/T-cell factor (TCF) complex and subsequent regulation of a set of target genes that have one or more TCF-binding elements (TBEs). Hyperactivation of this pathway has been implicated in numerous malignancies including human neuroendocrine tumors (NETs). Neurotensin (NT), an intestinal hormone, induces proliferation of several gastrointestinal (GI) cancers including cancers of the pancreas and colon. Here, we analyzed the human NT promoter in silico and found at least four consensus TBEs within the proximal promoter region. Using a combination of ChIP and luciferase reporter assays, we identified one TBE (located ∼900 bp proximal from the transcription start site) that was immunoprecipitated efficiently by TCF4-targeting antibody; mutation of this site attenuated the responsiveness to ß-catenin. We also confirmed that the promoter activity and the mRNA and protein expression levels of NT were increased by various Wnt pathway activators and decreased by Wnt inhibitors in NET cell lines BON and QGP-1, which express and secrete NT. Similarly, the intracellular content and secretion of NT were induced by Wnt3a in these cells. Finally, inhibition of NT signaling suppressed cell proliferation and anchorage-independent growth and decreased expression levels of growth-related proteins in NET cells. Our results indicate that NT is a direct target of the Wnt/ß-catenin pathway and may be a mediator for NET cell growth.


Asunto(s)
Tumores Neuroendocrinos/patología , Neurotensina/fisiología , Vía de Señalización Wnt/fisiología , beta Catenina/fisiología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica , Humanos , Neurotensina/antagonistas & inhibidores , Neurotensina/genética , Regiones Promotoras Genéticas , Receptores de Neurotensina/fisiología
16.
Carcinogenesis ; 35(6): 1341-51, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24510238

RESUMEN

Upregulation of fatty acid synthase (FASN), a key enzyme of de novo lipogenesis, is associated with metastasis in colorectal cancer (CRC). However, the mechanisms of regulation are unknown. Since angiogenesis is crucial for metastasis, we investigated the role of FASN in the neovascularization of CRC. The effect of FASN on tumor vasculature was studied in orthotopic CRCs, the chick embryo chorioallantoic membrane (CAM) and Matrigel plug models using immunohistochemistry, immunofluorescent staining and confocal microscopy. Cell secretion was evaluated by ELISA and antibody arrays. Proliferation, migration and tubulogenesis of endothelial cells (ECs) were assessed in CRC-EC coculture models. In this study, we found that stable knockdown of FASN decreased microvessel density in HT29 and HCT116 orthotopic CRCs and resulted in 'normalization' of tumor vasculature in both orthotopic and CAM models. Furthermore, FASN regulated secretion of pro- and antiangiogenic factors, including vascular endothelial growth factor-A (VEGF-A). Mechanisms associated with the antiangiogenic activity noted with knockdown of FASN included: downregulation of VEGF(189), upregulation of antiangiogenic isoform VEGF(165b) and a decrease in expression and activity of matrix metalloproteinase-9. Furthermore, conditioned medium from FASN knockdown CRC cells inhibited activation of vascular endothelial growth factor receptor-2 and its downstream signaling and decreased proliferation, migration and tubulogenesis of ECs as compared with control medium. Together, these results suggest that cancer cell-associated FASN regulates tumor vasculature through alteration of the profile of secreted angiogenic factors and regulation of their bioavailability. Inhibition of FASN upstream of VEGF-A and other angiogenic pathways can be a novel therapeutic strategy to prevent or inhibit metastasis in CRC.


Asunto(s)
Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Células Endoteliales/metabolismo , Ácido Graso Sintasas/genética , Neovascularización Patológica/genética , Animales , Línea Celular Tumoral , Embrión de Pollo , Modelos Animales de Enfermedad , Ácido Graso Sintasas/metabolismo , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Xenoinjertos , Humanos , Masculino , Metaloproteinasa 9 de la Matriz/metabolismo , Neovascularización Patológica/metabolismo , Transducción de Señal , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo
17.
Gynecol Oncol ; 133(2): 263-7, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24525114

RESUMEN

OBJECTIVE: In the post-radiation patient, late vascular sequelae and fibrosis predispose women to poor tissue healing, such that small tissue injuries could theoretically evolve into much larger ones such as fistulae. We sought to determine if a correlation exists between invasive procedures such as post-treatment biopsies and the subsequent development of gynecologic fistulae. METHODS: A retrospective review was performed evaluating all patients treated for cervical cancer at our institution between 1997 and 2010. Biopsies or pelvic surgeries were included if performed within the radiated field, and evaluated in a multivariate predictive model for development of gynecologic fistulae. RESULTS: Out of 325 total patients, 27 patients with fistulae were identified (8.2%). 14 fistulae (51.9%) were considered toxicity-related, 6 (22.2%) resulted from primary disease, and 7 (25.9%) were attributable to recurrent disease. Eighty-nine patients underwent an invasive procedure (55 biopsies and 34 pelvic surgeries). Recurrent and/or residual cancer was found in 28 (31.5%) specimens, and of the 61 patients who underwent an invasive procedure and were not found to have evidence of recurrent disease, 9 (14.8%) subsequently developed a fistula at a median 3.08 months. An elevated dose of radiation to the rectum (OR 1.001 for dose >72 Gy, p=0.0005), advancing tumor stage (OR 5.38 for stage III, OR 10.47 for stage IV, p=0.0288), and a post-radiation biopsy (OR 5.27, p=0.013) were significantly associated with fistula development. CONCLUSIONS: Performing a biopsy in an irradiated field is associated with a relatively low yield and significantly contributes to the risk for fistula development.


Asunto(s)
Adenocarcinoma/radioterapia , Biopsia/efectos adversos , Carcinoma de Células Escamosas/radioterapia , Complicaciones Posoperatorias/etiología , Traumatismos por Radiación/complicaciones , Neoplasias del Cuello Uterino/radioterapia , Fístula Vaginal/etiología , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Adenoescamoso/patología , Carcinoma Adenoescamoso/radioterapia , Carcinoma Adenoescamoso/cirugía , Carcinoma de Células Pequeñas/patología , Carcinoma de Células Pequeñas/radioterapia , Carcinoma de Células Pequeñas/cirugía , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/cirugía , Femenino , Procedimientos Quirúrgicos Ginecológicos , Humanos , Fístula Intestinal/etiología , Persona de Mediana Edad , Análisis Multivariante , Fístula Rectovaginal/etiología , Estudios Retrospectivos , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/cirugía , Fístula Vesicovaginal/etiología , Cicatrización de Heridas , Adulto Joven
18.
Pharm Res ; 31(6): 1450-9, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23619595

RESUMEN

PURPOSE: To develop novel hybrid paclitaxel (PTX) nanocrystals, in which bioactivatable (MMPSense® 750 FAST) and near infrared (Flamma Fluor® FPR-648) fluorophores are physically incorporated, and to evaluate their anticancer efficacy and diagnostic properties in breast cancer xenograft murine model. METHODS: The pure and hybrid paclitaxel nanocrystals were prepared by an anti-solvent method, and their physical properties were characterized. The tumor volume change and body weight change were evaluated to assess the treatment efficacy and toxicity. Bioimaging of treated mice was obtained non-invasively in vivo. RESULTS: The released MMPSense molecules from the hybrid nanocrystals were activated by matrix metalloproteinases (MMPs) in vivo, similarly to the free MMPSense, demonstrating its ability to monitor cancer progression. Concurrently, the entrapped FPR-648 was imaged at a different wavelength. Furthermore, when administered at 20 mg/kg, the nanocrystal formulations exerted comparable efficacy as Taxol®, but with decreased toxicity. CONCLUSIONS: Hybrid nanocrystals that physically integrated two fluorophores were successfully prepared from solution. Hybrid nanocrystals were shown not only exerting antitumor activity, but also demonstrating the potential of multi-modular bioimaging for diagnostics.


Asunto(s)
Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/uso terapéutico , Neoplasias/diagnóstico , Neoplasias/tratamiento farmacológico , Paclitaxel/administración & dosificación , Paclitaxel/uso terapéutico , Animales , Peso Corporal/efectos de los fármacos , Línea Celular Tumoral , Química Farmacéutica , Femenino , Colorantes Fluorescentes , Humanos , Metaloproteinasas de la Matriz/metabolismo , Ratones , Ratones Desnudos , Nanopartículas , Ensayos Antitumor por Modelo de Xenoinjerto
19.
Future Oncol ; 10(15): 2435-48, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24826798

RESUMEN

BACKGROUND: Targeting growth factor and survival pathways may delay endocrine-resistance in estrogen receptor-positive breast cancer. MATERIALS & METHODS: A pilot Phase II study adding sorafenib to endocrine therapy in 11 patients with metastatic estrogen receptor-positive breast cancer was conducted. Primary end point was response by RECIST after 3 months of sorafenib. Secondary end points included safety, time to progression and biomarker modulation. The study closed early owing to slow accrual. RESULTS: Eight out of 11 patients had progressive disease on study entry and three had stable disease. Of the ten evaluable patients, seven experienced stable disease (70%) and three experienced progressive diseas (30%), with a median time to progression of 6.1 months (8.4 months in the seven patients on tamoxifen). The serum samples demonstrated a significant reduction in VEGF receptor 2 and PDGF receptor-α. Microarray analysis identified 32 suppressed genes, no induced genes and 29 enriched Kyoto Encyclopedia of Genes and Genomes pathways. CONCLUSION: The strategy of adding a targeted agent to endocrine therapy upon resistance may be worthwhile testing in larger studies.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias de la Mama/tratamiento farmacológico , Niacinamida/análogos & derivados , Compuestos de Fenilurea/uso terapéutico , Adulto , Anciano , Biomarcadores de Tumor/sangre , Neoplasias Óseas/metabolismo , Neoplasias Óseas/mortalidad , Neoplasias Óseas/secundario , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/secundario , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Persona de Mediana Edad , Niacinamida/uso terapéutico , Proyectos Piloto , Inhibidores de Proteínas Quinasas/uso terapéutico , Receptores de Estrógenos/metabolismo , Sorafenib , Tamoxifeno/uso terapéutico , Resultado del Tratamiento
20.
Cell Prolif ; : e13757, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39329245

RESUMEN

Intestinal stem cells differentiate into absorptive enterocytes, characterised by increased brush border enzymes such as intestinal alkaline phosphatase (IAP), making up the majority (95%) of the terminally differentiated cells in the villus. Loss of integrity of the intestinal epithelium plays a key role in inflammatory diseases and gastrointestinal infection. Here, we show that the intestinal microRNA (miR)-27a-3p is an important regulator of intestinal epithelial cell proliferation and enterocyte differentiation. Repression of endogenous miR-27a-3p leads to increased enterocyte differentiation and decreased intestinal epithelial cell proliferation in mouse and human small intestinal organoids. Mechanistically, miR-27a-3p regulates intestinal cell differentiation and proliferation at least in part through the regulation of retinoic acid receptor α (RXRα), a modulator of Wnt/ß-catenin signalling. Repression of miR-27a-3p increases the expression of RXRα and concomitantly, decreases the expression of active ß-catenin and cyclin D1. In contrast, overexpression of miR-27a-3p mimic decreases the expression of RXRα and increases the expression of active ß-catenin and cyclin D1. Moreover, overexpression of the miR-27a-3p mimic results in impaired enterocyte differentiation and increases intestinal epithelial cell proliferation. These alterations were attenuated or blocked by Wnt inhibition. Our study demonstrates an miR-27a-3p/RXRα/Wnt/ß-catenin pathway that is important for the maintenance of enterocyte homeostasis in the small intestine.

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