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1.
Ann Surg Oncol ; 31(2): 1252-1263, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38006531

RESUMO

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.


Assuntos
Neoplasias dos Ductos Biliares , Neoplasias Colorretais , Neoplasias Hepáticas , Dispositivos de Acesso Vascular , Humanos , Neoplasias Colorretais/patologia , Artéria Hepática/patologia , Estudos de Viabilidade , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Hepáticas/secundário , Infusões Intra-Arteriais , Ductos Biliares Intra-Hepáticos/patologia , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/etiologia
2.
FASEB J ; 35(5): e21371, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33811694

RESUMO

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.


Assuntos
Ácidos e Sais Biliares/metabolismo , Intestinos/fisiologia , Neurotensina/fisiologia , Nutrientes/metabolismo , Obesidade/fisiopatologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Células CACO-2 , Dieta Hiperlipídica , Feminino , Humanos , Masculino , Camundongos
3.
J Neurooncol ; 156(1): 153-161, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34820776

RESUMO

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.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Antineoplásicos Alquilantes/efeitos adversos , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Temozolomida/efeitos adversos , Trombocitopenia/induzido quimicamente
4.
Nature ; 533(7603): 411-5, 2016 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-27193687

RESUMO

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.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Neurotensina/metabolismo , Obesidade/induzido quimicamente , Obesidade/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Linhagem Celular , Modelos Animais de Doenças , Drosophila melanogaster/citologia , Drosophila melanogaster/enzimologia , Drosophila melanogaster/metabolismo , Células Enteroendócrinas/metabolismo , Ativação Enzimática , Corpo Adiposo/metabolismo , Ácidos Graxos/metabolismo , Fígado Gorduroso/metabolismo , Fígado Gorduroso/prevenção & controle , Feminino , Humanos , Resistência à Insulina/fisiologia , Mucosa Intestinal/metabolismo , Intestinos/citologia , Metabolismo dos Lipídeos , Masculino , Camundongos , Pessoa de Meia-Idade , Neurotensina/sangue , Neurotensina/deficiência , Neurotensina/genética , Obesidade/sangue , Obesidade/prevenção & controle , Precursores de Proteínas/sangue , Precursores de Proteínas/metabolismo
5.
Int J Mol Sci ; 23(12)2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35742953

RESUMO

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.


Assuntos
Adenoma , Neoplasias Colorretais , Adenoma/genética , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Modelos Animais de Doenças , Regulação para Baixo/genética , Ácido Graxo Sintase Tipo I/genética , Ácido Graxo Sintase Tipo I/metabolismo , Ácido Graxo Sintases/genética , Ácido Graxo Sintases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Transcriptoma
6.
FASEB J ; 34(6): 8596-8610, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32359121

RESUMO

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.


Assuntos
Disbiose/metabolismo , Inflamação/metabolismo , Metaloproteinase 7 da Matriz/metabolismo , Neurotensina/metabolismo , alfa-Defensinas/metabolismo , Tecido Adiposo/metabolismo , Animais , Citocinas/metabolismo , Dieta Hiperlipídica/efeitos adversos , Disbiose/patologia , Microbioma Gastrointestinal/fisiologia , Inflamação/patologia , Resistência à Insulina/fisiologia , Intestinos/patologia , Masculino , Camundongos , Camundongos Obesos , NF-kappa B/metabolismo , Obesidade/metabolismo , Celulas de Paneth/metabolismo , Transdução de Sinais/fisiologia
7.
J Biol Chem ; 294(18): 7516-7527, 2019 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-30885944

RESUMO

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.


Assuntos
Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , NADH Desidrogenase/metabolismo , Invasividade Neoplásica , Proteína A4 de Ligação a Cálcio da Família S100/metabolismo , Regulação para Cima , Trifosfato de Adenosina/biossíntese , Linhagem Celular Tumoral , Inativação Gênica , Glicólise , Humanos , NADH Desidrogenase/genética , Metástase Neoplásica , Transdução de Sinais
8.
Pharm Stat ; 19(3): 214-229, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31749311

RESUMO

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.


Assuntos
Ensaios Clínicos Fase II como Assunto , Determinação de Ponto Final , Projetos de Pesquisa , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/terapia , Ensaios Clínicos Fase II como Assunto/estatística & dados numéricos , Interpretação Estatística de Dados , Determinação de Ponto Final/estatística & dados numéricos , Humanos , Imunoterapia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/terapia , Modelos Estatísticos , Intervalo Livre de Progressão , Projetos de Pesquisa/estatística & dados numéricos , Análise de Sobrevida , Fatores de Tempo
10.
Pharm Stat ; 18(2): 212-222, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30458583

RESUMO

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.


Assuntos
Ensaios Clínicos Fase II como Assunto/métodos , Modelos Estatísticos , Neoplasias/terapia , Projetos de Pesquisa , Interpretação Estatística de Dados , Determinação de Ponto Final , Humanos , Imunoterapia/métodos , Terapia de Alvo Molecular , Tamanho da Amostra , Resultado do Tratamento
11.
Nucleic Acids Res ; 44(20): e151, 2016 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-27471031

RESUMO

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.


Assuntos
Biologia Computacional/métodos , Perfilação da Expressão Gênica/métodos , MicroRNAs/genética , Modelos Estatísticos , RNA Mensageiro/genética , Algoritmos , Simulação por Computador , Conjuntos de Dados como Assunto , Regulação da Expressão Gênica , Reprodutibilidade dos Testes
12.
Biochim Biophys Acta ; 1852(10 Pt A): 2013-23, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26187040

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-25086043

RESUMO

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.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Autofagia , Classe III de Fosfatidilinositol 3-Quinases/metabolismo , Proteínas de Membrana/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Transativadores/fisiologia , Sequência de Aminoácidos , Proteínas Relacionadas à Autofagia , Proteína Beclina-1 , Proteínas de Fluorescência Verde/biossíntese , Células Hep G2 , Humanos , Dados de Sequência Molecular , Complexos Multiproteicos/metabolismo , Fagossomos/metabolismo , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Mapas de Interação de Proteínas , Transporte Proteico , Proteínas Recombinantes de Fusão/biossíntese , Transativadores/química
14.
Breast Cancer Res ; 17: 25, 2015 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-25849745

RESUMO

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.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Neoplasias de Mama Triplo Negativas/metabolismo , Fator 3 Ativador da Transcrição/metabolismo , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático , Transição Epitelial-Mesenquimal/genética , Feminino , Expressão Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Pulmonares/secundário , Camundongos , Terapia de Alvo Molecular , Invasividade Neoplásica , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Prognóstico , Fator de Crescimento Transformador beta/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/patologia , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Int J Cancer ; 136(6): 1475-81, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25098665

RESUMO

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.


Assuntos
Tumores Neuroendócrinos/patologia , Neurotensina/fisiologia , Via de Sinalização Wnt/fisiologia , beta Catenina/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Humanos , Neurotensina/antagonistas & inibidores , Neurotensina/genética , Regiões Promotoras Genéticas , Receptores de Neurotensina/fisiologia
16.
Carcinogenesis ; 35(6): 1341-51, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24510238

RESUMO

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.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Células Endoteliais/metabolismo , Ácido Graxo Sintases/genética , Neovascularização Patológica/genética , Animais , Linhagem Celular Tumoral , Embrião de Galinha , Modelos Animais de Doenças , Ácido Graxo Sintases/metabolismo , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Xenoenxertos , Humanos , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Neovascularização Patológica/metabolismo , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
17.
Gynecol Oncol ; 133(2): 263-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24525114

RESUMO

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.


Assuntos
Adenocarcinoma/radioterapia , Biópsia/efeitos adversos , Carcinoma de Células Escamosas/radioterapia , Complicações Pós-Operatórias/etiologia , Lesões por Radiação/complicações , Neoplasias do Colo do Útero/radioterapia , Fístula Vaginal/etiologia , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Adenoescamoso/patologia , Carcinoma Adenoescamoso/radioterapia , Carcinoma Adenoescamoso/cirurgia , Carcinoma de Células Pequenas/patologia , Carcinoma de Células Pequenas/radioterapia , Carcinoma de Células Pequenas/cirurgia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Feminino , Procedimentos Cirúrgicos em Ginecologia , Humanos , Fístula Intestinal/etiologia , Pessoa de Meia-Idade , Análise Multivariada , Fístula Retovaginal/etiologia , Estudos Retrospectivos , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/cirurgia , Fístula Vesicovaginal/etiologia , Cicatrização , Adulto Jovem
18.
Pharm Res ; 31(6): 1450-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23619595

RESUMO

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.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Paclitaxel/administração & dosagem , Paclitaxel/uso terapêutico , Animais , Peso Corporal/efeitos dos fármacos , Linhagem Celular Tumoral , Química Farmacêutica , Feminino , Corantes Fluorescentes , Humanos , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Nus , Nanopartículas , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Future Oncol ; 10(15): 2435-48, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24826798

RESUMO

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.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Niacinamida/análogos & derivados , Compostos de Fenilureia/uso terapêutico , Adulto , Idoso , Biomarcadores Tumorais/sangue , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/secundário , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/secundário , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Niacinamida/uso terapêutico , Projetos Piloto , Inibidores de Proteínas Quinases/uso terapêutico , Receptores de Estrogênio/metabolismo , Sorafenibe , Tamoxifeno/uso terapêutico , Resultado do Tratamento
20.
Atherosclerosis ; 392: 117479, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38423808

RESUMO

BACKGROUND AND AIMS: Obesity and type 2 diabetes are significant risk factors for atherosclerotic cardiovascular disease (CVD) worldwide, but the underlying pathophysiological links are poorly understood. Neurotensin (NT), a 13-amino-acid hormone peptide, facilitates intestinal fat absorption and contributes to obesity in mice fed a high-fat diet. Elevated levels of pro-NT (a stable NT precursor produced in equimolar amounts relative to NT) are associated with obesity, type 2 diabetes, and CVD in humans. Whether NT is a causative factor in CVD is unknown. METHODS: Nt+/+ and Nt-/- mice were either injected with adeno-associated virus encoding PCSK9 mutants or crossed with Ldlr-/- mice and fed a Western diet. Atherosclerotic plaques were analyzed by en face analysis, Oil Red O and CD68 staining. In humans, we evaluated the association between baseline pro-NT and growth of carotid bulb thickness after 16.4 years. Lipidomic profiles were analyzed. RESULTS: Atherosclerotic plaque formation is attenuated in Nt-deficient mice through mechanisms that are independent of reductions in circulating cholesterol and triglycerides but associated with remodeling of the plasma triglyceride pool. An increasing plasma concentration of pro-NT predicts atherosclerotic events in coronary and cerebral arteries independent of all major traditional risk factors, indicating a strong link between NT and atherosclerosis. This plasma lipid profile analysis confirms the association of pro-NT with remodeling of the plasma triglyceride pool in atherosclerotic events. CONCLUSIONS: Our findings are the first to directly link NT to increased atherosclerosis and indicate the potential role for NT in preventive and therapeutic strategies for CVD.


Assuntos
Aterosclerose , Camundongos Knockout , Neurotensina , Placa Aterosclerótica , Triglicerídeos , Animais , Neurotensina/sangue , Triglicerídeos/sangue , Aterosclerose/sangue , Humanos , Masculino , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Feminino , Camundongos , Receptores de LDL/genética , Receptores de LDL/deficiência , Fatores de Risco , Ácidos Graxos/metabolismo , Ácidos Graxos/sangue , Pessoa de Meia-Idade , Precursores de Proteínas
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