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1.
J Cell Mol Med ; 23(10): 6885-6896, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31389667

RESUMO

Aberrant expression of Sialyl-Tn (STn) antigen correlates with poor prognosis and reduced patient survival. We demonstrated that expression of Tn and STn in pancreatic ductal adenocarcinoma (PDAC) is due to hypermethylation of Core 1 synthase specific molecular chaperone (COSMC) and enhanced the malignant properties of PDAC cells with an unknown mechanism. To explore the mechanism, we have genetically deleted COSMC in PDAC cells to express truncated O-glycans (SimpleCells, SC) which enhanced cell migration and invasion. Since epithelial-to-mesenchymal transition (EMT) play a vital role in metastasis, we have analysed the induction of EMT in SC cells. Expressions of the mesenchymal markers were significantly high in SC cells as compared to WT cells. Equally, we found reduced expressions of the epithelial markers in SC cells. Re-expression of COSMC in SC cells reversed the induction of EMT. In addition to this, we also observed an increased cancer stem cell population in SC cells. Furthermore, orthotopic implantation of T3M4 SC cells into athymic nude mice resulted in significantly larger tumours and reduced animal survival. Altogether, these results suggest that aberrant expression of truncated O-glycans in PDAC cells enhances the tumour aggressiveness through the induction of EMT and stemness properties.

2.
Sci Rep ; 9(1): 9665, 2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31273306

RESUMO

Keratan sulfate (KS) is a sulfated linear polymer of N-acetyllactosamine. Proteoglycans carrying keratan sulfate epitopes were majorly observed in cornea, cartilage and brain; and mainly involved in embryonic development, cornea transparency, and wound healing process. Recently, expression of KS in cancer has been shown to be highly associated with advanced tumor grade and poor prognosis. Therefore, we aimed to identify the expression of KS epitope in human pancreatic cancer primary and metastatic tumor lesions. Immunohistochemical analysis of KS expression was performed on primary pancreatic tumors and metastatic tissues. We observed an increased expression of KS epitope on primary tumor tissues compared to uninvolved normal and tumor stroma; and is associated with worse overall survival. Moreover, lung metastatic tumors show a higher-level expression of KS compared to primary tumors. Interestingly, KS biosynthesis specific glycosyltransferases expression was differentially regulated in metastatic pancreatic tumors. Taken together, these results indicate that aberrant expression of KS is predictive of pancreatic cancer progression and metastasis and may serve as a novel prognostic biomarker for pancreatic cancer.

3.
FEBS Lett ; 593(19): 2751-2761, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31283009

RESUMO

Aberrant expression of the glycoprotein mucin-1 (MUC1) has been associated with pancreatic cancer progression and metastasis as a result of mediating the oncogenic transcriptional regulation of target genes. In the present study, we demonstrate that MUC1 downregulates the expression of the tumor suppressor polypeptide N-acetylgalactosaminyltransferase 5 in pancreatic cancer. ChIP-on-chip analysis revealed that the MUC1 cytoplasmic tail binds to regulatory elements in the GALNT5 gene. Additionally, MUC1 increases binding of p53 and c-Jun and decreases the binding of Sp1 to the proximal promoter and exonic regions of GALNT5. We also observed that expression of N-acetylgalactosaminyltransferase 5 is inversionally proportional to MUC1 expression in human pancreatic cancer. These results demonstrate that MUC1 downregulates the expression of N-acetylgalactosaminyltransferase 5 in pancreatic cancer by modifying the promoter occupancy of transcription factors through its cytoplasmic domain.

4.
J Pharmacol Exp Ther ; 370(3): 894-901, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30683666

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers. A combination of cisplatin (CDDP) and gemcitabine (Gem) treatment has shown favorable clinical results for metastatic disease; both are limited by toxicities and nontargeted delivery. More than 80% of PDAC aberrantly expresses the sialyl Tn (STn) antigen due to the loss of function of the core 1ß3-Gal-T-specific molecular chaperone, a specific chaperone for the activity of core 1 ß3-galactosyltransferase or C1GalT. Here, we report the development of polymeric nanogels (NGs) loaded with CDDP and coated with an anti-STn antigen-specific antibody (TKH2 monoclonal antibody) for the targeted treatment of PDAC. TKH2-functionalized, CDDP-loaded NGs delivered a significantly higher amount of platinum into the cells and tumors expressing STn antigens. We also confirmed that a synergistic cytotoxic effect of sequential exposure of pancreatic cancer cells to Gem followed by CDDP can be mimicked by the codelivery of CDDP-loaded NGs (NG/CDDP) and free Gem. In a murine orthotopic model of PDAC, combined simultaneous treatment with Gem and targeted NG/CDDP significantly attenuated tumor growth with no detectable acute toxicity. Altogether, these results suggest that combination therapy consisting of Gem followed by TKH2-conjugated CDDP NGs induces highly synergistic therapeutic efficacy against pancreatic cancer. Our results offer the basis for development of combination drug regimens using targeted nanomedicines to increase treatment effectiveness and improve outcomes of PDAC therapy.

5.
Mol Cancer ; 18(1): 14, 2019 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-30665410

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with high morbidity and mortality worldwide. To date, limited therapeutic achievements targeting cell proliferation and related mechanisms has led researchers to focus on the microenvironment where pancreatic cancers develop. The anomalous proliferation of stromal cells, such as pancreatic stellate cells, and an increased deposition of altered matrix proteins create an environment that facilitates tumor growth, metastasis and drug resistance. Here, we summarize our understanding of recent advances in research about the role of fibrosis in pancreatic cancer progression, with particular emphasize on the involvement of fibrotic machineries such as wound healing, extra cellular matrix degradation, and epithelial-to-mesenchymal transition. The precise influence of these mechanisms on the biological behaviors and growth of cancer cells has great impact on clinical therapy and therefore deserves more attention. We also discuss the role of various stromal components in conferring drug resistance to PDAC which further worsening the pessimistic disease prognosis. A more in depth understanding of cancer-stroma crosstalk within the tumor microenvironment and stroma based clinical and translational therapies may provide new therapeutic strategies for the prevention of pancreatic cancer progression.


Assuntos
Carcinoma Ductal Pancreático/patologia , Fibrose/patologia , Neoplasias Pancreáticas/patologia , Células Estromais/patologia , Animais , Comunicação Celular/fisiologia , Proliferação de Células/fisiologia , Humanos , Prognóstico , Microambiente Tumoral/fisiologia
6.
J Med Chem ; 59(10): 5121-7, 2016 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-27077228

RESUMO

Design, synthesis, and evaluation of α-methylene-γ-butyrolactone analogues and their evaluation as anticancer agents is described. SAR identified a spirocyclic analogue 19 that inhibited TNFα-induced NF-κB activity, cancer cell growth and tumor growth in an ovarian cancer model. A second iteration of synthesis and screening identified 29 which inhibited cancer cell growth with low-µM potency. Our data suggest that an isatin-derived spirocyclic α-methylene-γ-butyrolactone is a suitable core for optimization to identify novel anticancer agents.


Assuntos
Antineoplásicos/farmacologia , Isatina/farmacologia , Compostos de Espiro/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Isatina/química , Estrutura Molecular , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Compostos de Espiro/síntese química , Compostos de Espiro/química , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo
7.
Oncotarget ; 6(4): 2064-75, 2015 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-25576918

RESUMO

Amyloid precursor-like protein 2 (APLP2) is aberrantly expressed in pancreatic cancer. Here we showed that APLP2 is increased in pancreatic cancer metastases, particularly in metastatic lesions found in the diaphragm and intestine. Examination of matched human primary tumor-liver metastasis pairs showed that 38.1% of the patients had positive APLP2 expression in both the primary tumor and the corresponding liver metastasis. Stable knock-down of APLP2 expression (with inducible shRNA) in pancreatic cancer cells reduced the ability of these cells to migrate and invade. Loss of APLP2 decreased cortical actin and increased intracellular actin filaments in pancreatic cancer cells. Down-regulation of APLP2 decreased the weight and metastasis of orthotopically transplanted pancreatic tumors in nude mice.


Assuntos
Citoesqueleto de Actina/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Proliferação de Células , Proteínas do Tecido Nervoso/metabolismo , Neoplasias Pancreáticas/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Antibacterianos/farmacologia , Linhagem Celular Tumoral , Movimento Celular , Regulação para Baixo/efeitos dos fármacos , Doxiciclina/farmacologia , Feminino , Citometria de Fluxo , Humanos , Immunoblotting , Imuno-Histoquímica , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Camundongos Nus , Proteínas do Tecido Nervoso/genética , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Interferência de RNA , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/genética , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Cancer Metab ; 2: 18, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25228990

RESUMO

BACKGROUND: Aberrant energy metabolism is a hallmark of cancer. To fulfill the increased energy requirements, tumor cells secrete cytokines/factors inducing muscle and fat degradation in cancer patients, a condition known as cancer cachexia. It accounts for nearly 20% of all cancer-related deaths. However, the mechanistic basis of cancer cachexia and therapies targeting cancer cachexia thus far remain elusive. A ketogenic diet, a high-fat and low-carbohydrate diet that elevates circulating levels of ketone bodies (i.e., acetoacetate, ß-hydroxybutyrate, and acetone), serves as an alternative energy source. It has also been proposed that a ketogenic diet leads to systemic metabolic changes. Keeping in view the significant role of metabolic alterations in cancer, we hypothesized that a ketogenic diet may diminish glycolytic flux in tumor cells to alleviate cachexia syndrome and, hence, may provide an efficient therapeutic strategy. RESULTS: We observed reduced glycolytic flux in tumor cells upon treatment with ketone bodies. Ketone bodies also diminished glutamine uptake, overall ATP content, and survival in multiple pancreatic cancer cell lines, while inducing apoptosis. A decrease in levels of c-Myc, a metabolic master regulator, and its recruitment on glycolytic gene promoters, was in part responsible for the metabolic phenotype in tumor cells. Ketone body-induced intracellular metabolomic reprogramming in pancreatic cancer cells also leads to a significantly diminished cachexia in cell line models. Our mouse orthotopic xenograft models further confirmed the effect of a ketogenic diet in diminishing tumor growth and cachexia. CONCLUSIONS: Thus, our studies demonstrate that the cachectic phenotype is in part due to metabolic alterations in tumor cells, which can be reverted by a ketogenic diet, causing reduced tumor growth and inhibition of muscle and body weight loss.

9.
Proc Natl Acad Sci U S A ; 111(39): E4066-75, 2014 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-25118277

RESUMO

Aberrant expression of immature truncated O-glycans is a characteristic feature observed on virtually all epithelial cancer cells, and a very high frequency is observed in early epithelial premalignant lesions that precede the development of adenocarcinomas. Expression of the truncated O-glycan structures Tn and sialyl-Tn is strongly associated with poor prognosis and overall low survival. The genetic and biosynthetic mechanisms leading to accumulation of truncated O-glycans are not fully understood and include mutation or dysregulation of glycosyltransferases involved in elongation of O-glycans, as well as relocation of glycosyltransferases controlling initiation of O-glycosylation from Golgi to endoplasmic reticulum. Truncated O-glycans have been proposed to play functional roles for cancer-cell invasiveness, but our understanding of the biological functions of aberrant glycosylation in cancer is still highly limited. Here, we used exome sequencing of most glycosyltransferases in a large series of primary and metastatic pancreatic cancers to rule out somatic mutations as a cause of expression of truncated O-glycans. Instead, we found hypermethylation of core 1 ß3-Gal-T-specific molecular chaperone, a key chaperone for O-glycan elongation, as the most prevalent cause. We next used gene editing to produce isogenic cell systems with and without homogenous truncated O-glycans that enabled, to our knowledge, the first polyomic and side-by-side evaluation of the cancer O-glycophenotype in an organotypic tissue model and in xenografts. The results strongly suggest that truncation of O-glycans directly induces oncogenic features of cell growth and invasion. The study provides support for targeting cancer-specific truncated O-glycans with immunotherapeutic measures.


Assuntos
Neoplasias Pancreáticas/metabolismo , Polissacarídeos/química , Polissacarídeos/metabolismo , Animais , Adesão Celular , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Exoma/genética , Glicômica , Glicosilação , Xenoenxertos , Humanos , Camundongos , Camundongos Knockout , Camundongos Nus , Camundongos SCID , Chaperonas Moleculares/química , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Mutação , Invasividade Neoplásica , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Fenótipo , Proteômica , Transdução de Sinais
10.
Cancer Res ; 74(5): 1609-20, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24371222

RESUMO

The mechanisms by which MUC1 and p120 catenin contribute to progression of cancers from early transformation to metastasis are poorly understood. Here we show that p120 catenin ARM domains 1, 3-5, and 8 mediate interactions between p120 catenin and MUC1, and that these interactions modulate dynamic properties of cell adhesion, motility, and metastasis of pancreatic cancer cells. We also show that different isoforms of p120 catenin, when coexpressed with MUC1, create cells that exhibit distinct patterns of motility in culture (motility independent of cell adhesion, motility within a monolayer while exchanging contacts with other cells, and unified motility while maintaining static epithelial contacts) and patterns of metastasis. The results provide new insight into the dynamic interplay between cell adhesion and motility and the relationship of these to the metastatic process.


Assuntos
Cateninas/genética , Cateninas/metabolismo , Adesão Celular/genética , Movimento Celular/genética , Mucina-1/genética , Mucina-1/metabolismo , Metástase Neoplásica/genética , Caderinas/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Humanos , beta Catenina/genética , beta Catenina/metabolismo
11.
PLoS One ; 8(10): e73356, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24204560

RESUMO

Transmembrane mucins, MUC4 and MUC16 are associated with tumor progression and metastatic potential in human pancreatic adenocarcinoma. We discovered that miR-200c interacts with specific sequences within the coding sequence of MUC4 and MUC16 mRNAs, and evaluated the regulatory nature of this association. Pancreatic cancer cell lines S2.028 and T3M-4 transfected with miR-200c showed a 4.18 and 8.50 fold down regulation of MUC4 mRNA, and 4.68 and 4.82 fold down regulation of MUC16 mRNA compared to mock-transfected cells, respectively. A significant reduction of glycoprotein expression was also observed. These results indicate that miR-200c overexpression regulates MUC4 and MUC16 mucins in pancreatic cancer cells by directly targeting the mRNA coding sequence of each, resulting in reduced levels of MUC4 and MUC16 mRNA and protein. These data suggest that, in addition to regulating proteins that modulate EMT, miR-200c influences expression of cell surface mucins in pancreatic cancer.


Assuntos
Antígeno Ca-125/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Membrana/genética , MicroRNAs/genética , Mucina-4/genética , Fases de Leitura Aberta , Neoplasias Pancreáticas/genética , Pareamento de Bases , Sequência de Bases , Sítios de Ligação , Antígeno Ca-125/metabolismo , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Ordem dos Genes , Humanos , Proteínas de Membrana/metabolismo , Mucina-4/metabolismo , Interferência de RNA
12.
PLoS One ; 8(10): e73306, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24143167

RESUMO

MUC1 is a transmembrane glycoprotein that modulates transcription via its cytoplasmic domain. We evaluated the capacity of MUC1 to regulate the global transcription of microRNAs in pancreatic cancer cells expressing MUC1. Results indicated that MUC1 regulated expression of at least 103 microRNAs. We evaluated further regulation of the microRNA transcript cluster miR-200c/141, which was among the most highly regulated microRNAs. We found that MUC1 directly interacted with ZEB1, a known transcriptional repressor of the miR-200c/141 cluster, at the promoter of miR-200c/141, and further reduced transcript production. These data indicate that signaling through MUC1 influences cancer progression by regulating transcription of microRNAs that are associated with the process of metastasis.


Assuntos
Progressão da Doença , MicroRNAs/genética , Mucina-1/metabolismo , Neoplasias Pancreáticas/patologia , Sequência de Aminoácidos , Linhagem Celular Tumoral , Proteínas de Homeodomínio/metabolismo , Humanos , Neoplasias Hepáticas/secundário , Mitose , Dados de Sequência Molecular , Mucina-1/química , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Fosfoproteínas/química , Fosfoproteínas/metabolismo , Fatores de Transcrição/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco
13.
Mol Cancer Ther ; 12(10): 2006-17, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23963361

RESUMO

Mantle cell lymphoma (MCL) is one of the most aggressive B-cell non-Hodgkin lymphomas with a median survival of approximately five years. Currently, there is no curative therapy available for refractory MCL because of relapse from therapy-resistant tumor cells. The NF-κB and mTOR pathways are constitutively active in refractory MCL leading to increased proliferation and survival. Targeting these pathways is an ideal strategy to improve therapy for refractory MCL. Therefore, we investigated the in vitro and in vivo antilymphoma activity and associated molecular mechanism of action of a novel compound, 13-197, a quinoxaline analog that specifically perturbs IκB kinase (IKK) ß, a key regulator of the NF-κB pathway. 13-197 decreased the proliferation and induced apoptosis in MCL cells including therapy-resistant cells compared with control cells. Furthermore, we observed downregulation of IκBα phosphorylation and inhibition of NF-κB nuclear translocation by 13-197 in MCL cells. In addition, NF-κB-regulated genes such as cyclin D1, Bcl-XL, and Mcl-1 were downregulated in 13-197-treated cells. In addition, 13-197 inhibited the phosphorylation of S6K and 4E-BP1, the downstream molecules of mTOR pathway that are also activated in refractory MCL. Further, 13-197 reduced the tumor burden in vivo in the kidney, liver, and lungs of therapy-resistant MCL-bearing nonobese diabetic severe-combined immunodeficient (NOD/SCID) mice compared with vehicle-treated mice; indeed, 13-197 significantly increased the survival of MCL-transplanted mice. Together, results suggest that 13-197 as a single agent disrupts the NF-κB and mTOR pathways leading to suppression of proliferation and increased apoptosis in malignant MCL cells including reduction in tumor burden in mice.


Assuntos
Quinase I-kappa B/genética , Linfoma de Célula do Manto/tratamento farmacológico , NF-kappa B/biossíntese , Compostos de Fenilureia/administração & dosagem , Quinoxalinas/administração & dosagem , Serina-Treonina Quinases TOR/biossíntese , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Quinase I-kappa B/biossíntese , Linfoma de Célula do Manto/genética , Linfoma de Célula do Manto/patologia , Camundongos , Terapia de Alvo Molecular , NF-kappa B/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Int J Cancer ; 133(12): 2824-33, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23754791

RESUMO

Core 3-derived glycans, a major type of O-glycan expressed by normal epithelial cells of the gastrointestinal tract, are downregulated during malignancy because of loss of expression of functional ß3-N-acetylglucosaminyltransferase-6 (core 3 synthase). We investigated the expression of core 3 synthase in normal pancreas and pancreatic cancer and evaluated the biological effects of re-expressing core 3 synthase in pancreatic cancer cells that had lost expression. We determined that pancreatic tumors and tumor cell lines have lost expression of core 3 synthase. Therefore, we re-expressed core 3 synthase in human pancreatic cancer cells (Capan-2 and FG) to investigate the contribution of core 3 glycans to malignant progression. Pancreatic cancer cells expressing core 3 synthase showed reduced in vitro cell proliferation, migration and invasion compared to vector control cells. Expression of core 3 O-glycans induced altered expression of ß1 integrin, decreased activation of focal adhesion kinase, led to the downregulation of expression of several genes including REG1α and FGFR3 and altered lamellipodia formation. The addition of a GlcNAc residue by core 3 synthase leads to the extension of the tumor-associated Tn structure on MUC1. Orthotopic injection of FG cells expressing core 3 synthase into the pancreas of nude mice produced significantly smaller tumors and decreased metastasis to the surrounding tissues compared to vector control FG cells. These findings indicate that expression of core 3-derived O-glycans in pancreatic cancer cells suppresses tumor growth and metastasis through modulation of glycosylation of mucins and other cell surface and extracellular matrix proteins.


Assuntos
Proliferação de Células , N-Acetilglucosaminiltransferases/fisiologia , Neoplasias Pancreáticas/patologia , Actinas/metabolismo , Linhagem Celular Tumoral , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Integrina alfa2beta1/análise , Mucina-1/metabolismo , N-Acetilglucosaminiltransferases/genética , N-Acetilglucosaminiltransferases/metabolismo , Metástase Neoplásica
15.
Clin Cancer Res ; 19(8): 2025-35, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23444213

RESUMO

PURPOSE: The presence of TNF-α in approximately 50% of surgically resected tumors suggests that the canonical NF-κB and the mTOR pathways are activated. Inhibitor of IκB kinase ß (IKKß) acts as the signaling node that regulates transcription via the p-IκBα/NF-κB axis and regulates translation via the mTOR/p-S6K/p-eIF4EBP axis. A kinome screen identified a quinoxaline urea analog 13-197 as an IKKß inhibitor. We hypothesized that targeting the NF-κB and mTOR pathways with 13-197 will be effective in malignancies driven by these pathways. EXPERIMENTAL DESIGN: Retrospective clinical and preclinical studies in pancreas cancers have implicated NF-κB. We examined the effects of 13-197 on the downstream targets of the NF-κB and mTOR pathways in pancreatic cancer cells, pharmacokinetics, toxicity and tumor growth, and metastases in vivo. RESULTS: 13-197 inhibited the kinase activity of IKKß in vitro and TNF-α-mediated NF-κB transcription in cells with low-µmol/L potency. 13-197 inhibited the phosphorylation of IκBα, S6K, and eIF4EBP, induced G1 arrest, and downregulated the expression of antiapoptotic proteins in pancreatic cancer cells. Prolonged administration of 13-197 did not induce granulocytosis and protected mice from lipopolysaccharide (LPS)-induced death. Results also show that 13-197 is orally available with extensive distribution to peripheral tissues and inhibited tumor growth and metastasis in an orthotopic pancreatic cancer model without any detectable toxicity. CONCLUSION: These results suggest that 13-197 targets IKKß and thereby inhibits mTOR and NF-κB pathways. Oral availability along with in vivo efficacy without obvious toxicities makes this quinoxaline urea chemotype a viable cancer therapeutic.


Assuntos
Antineoplásicos/farmacologia , Quinase I-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Proteínas Reguladoras de Apoptose/metabolismo , Área Sob a Curva , Western Blotting , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Quinase I-kappa B/metabolismo , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Compostos de Fenilureia/química , Compostos de Fenilureia/farmacocinética , Compostos de Fenilureia/farmacologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/farmacologia , Quinoxalinas/química , Quinoxalinas/farmacocinética , Quinoxalinas/farmacologia , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Proc Natl Acad Sci U S A ; 109(34): 13787-92, 2012 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-22869720

RESUMO

Aberrant glucose metabolism is one of the hallmarks of cancer that facilitates cancer cell survival and proliferation. Here, we demonstrate that MUC1, a large, type I transmembrane protein that is overexpressed in several carcinomas including pancreatic adenocarcinoma, modulates cancer cell metabolism to facilitate growth properties of cancer cells. MUC1 occupies the promoter elements of multiple genes directly involved in glucose metabolism and regulates their expression. Furthermore, MUC1 expression enhances glycolytic activity in pancreatic cancer cells. We also demonstrate that MUC1 expression enhances in vivo glucose uptake and expression of genes involved in glucose uptake and metabolism in orthotopic implantation models of pancreatic cancer. The MUC1 cytoplasmic tail is known to activate multiple signaling pathways through its interactions with several transcription factors/coregulators at the promoter elements of various genes. Our results indicate that MUC1 acts as a modulator of the hypoxic response in pancreatic cancer cells by regulating the expression/stability and activity of hypoxia-inducible factor-1α (HIF-1α). MUC1 physically interacts with HIF-1α and p300 and stabilizes the former at the protein level. By using a ChIP assay, we demonstrate that MUC1 facilitates recruitment of HIF-1α and p300 on glycolytic gene promoters in a hypoxia-dependent manner. Also, by metabolomic studies, we demonstrate that MUC1 regulates multiple metabolite intermediates in the glucose and amino acid metabolic pathways. Thus, our studies indicate that MUC1 acts as a master regulator of the metabolic program and facilitates metabolic alterations in the hypoxic environments that help tumor cells survive and proliferate under such conditions.


Assuntos
Regulação Neoplásica da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Mucina-1/fisiologia , Neoplasias Pancreáticas/metabolismo , Animais , Feminino , Glucose/metabolismo , Glutamina/metabolismo , Glicólise , Humanos , Ácidos Cetoglutáricos/metabolismo , Camundongos , Camundongos Nus , Modelos Biológicos , Mucina-1/química , Via de Pentose Fosfato , Regiões Promotoras Genéticas , Transdução de Sinais , Fatores de Transcrição de p300-CBP/metabolismo
18.
Biochem Biophys Res Commun ; 409(3): 436-41, 2011 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-21596021

RESUMO

Sialyl Lewis x (sLe(x)) plays an important role in cancer metastasis. But, the mechanism for its production in metastatic cancers remains unclear. The objective of current study was to examine the effects of a proinflammatory cytokine on the expression of glycosyltransferase and sulfotransferase genes involved in the synthesis of selectin ligands in a prostate cancer cell line. Androgen-independent human lymph node-derived metastatic prostate cancer cells (C-81 LNCaP), which express functional androgen receptor and mimic the castration-resistant advanced prostate cancer, were used. TNFα treatment of these cells increased their binding to P-, E- and L-selectins, anti-sLe(x) antibody, and anti-6-sulfo-sialyl Lewis x antibody by 12%, 240%, 43%, 248% and 21%, respectively. Also, the expression of C2GnT-1, B4GalT1, GlcNAc6ST3, and ST3Gal3 genes was significantly upregulated. Further treatment of TNFα-treated cells with either anti-sLe(x) antibody or E-selectin significantly suppressed their in vitro migration (81% and 52%, respectively) and invasion (45% and 56%, respectively). Our data indicate that TNFα treatment enhances the motility and invasion properties of LNCaP C-81 cells by increasing the formation of selectin ligands through stimulation of the expression of selective glycosyl- and sulfotransferase genes. These results support the hypothesis that inflammation contributes to cancer metastasis.


Assuntos
Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Glicosiltransferases/genética , Oligossacarídeos/biossíntese , Neoplasias da Próstata/patologia , Sulfotransferases/genética , Fator de Necrose Tumoral alfa/fisiologia , Linhagem Celular Tumoral , Movimento Celular , Selectina E/metabolismo , Humanos , Selectina L/metabolismo , Ligantes , Masculino , Invasividade Neoplásica , Selectina-P/metabolismo , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/genética , Fator de Necrose Tumoral alfa/farmacologia
19.
Glycoconj J ; 26(1): 75-81, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18670876

RESUMO

Human prostate cancer LNCaP cells including C-33 and C-81 cells were originally derived from the lymph nodes of a patient with metastatic prostate cancer. These two cells were employed for characterization of L-selectin ligand and in vitro tumorigenicity, because they mimic the clinical conditions of early and late-stage human prostate cancer. C-81 cells exhibit higher in vitro migratory and invasive properties as compared with C-33 cells. We find that the L-selectin ligand and mucin glycan-associated MECA-79 epitope were elevated in C-81 cells. An increase of these glycotopes positively correlates with elevated tumorigenicity and expression of key glycosyl- and sulfotransferase genes. These results suggest that modulated expression of selective glycogenes correlates with altered tumorigenicity of cancer cells.


Assuntos
Antígenos de Superfície/biossíntese , Epitopos/metabolismo , Regulação Leucêmica da Expressão Gênica , Linfonodos/metabolismo , Proteínas de Membrana/biossíntese , Mucinas/metabolismo , Neoplasias da Próstata/metabolismo , Linhagem Celular Tumoral , Glucosiltransferases/metabolismo , Humanos , Selectina L/metabolismo , Linfonodos/patologia , Masculino , Metástase Neoplásica , Neoplasias da Próstata/patologia , Sulfotransferases/metabolismo
20.
Int J Biochem Cell Biol ; 40(9): 1944-55, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18373939

RESUMO

The cytomegalovirus promoter is a very potent promoter commonly used for driving the expression of transgenes, though it gradually becomes silenced in stably transfected cells. We examined the methylation status of the cytomegalovirus promoter in two different cell lines and characterized its mechanisms of activation by dimethylsulfoxide and 5-Aza-2'-deoxycytidine. The cytomegalovirus promoter stably transfected into Chinese hamster ovary cells is suppressed by DNA methylation-independent mechanisms, which is different from the rat embryonic cardiomyoblast H9c2-Fluc.3 cells in which the cytomegalovirus promoter is silenced by methylation. Dimethylsulfoxide and 5-Aza-2'-deoxycytidine can activate the cytomegalovirus promoter in both cell types by overlapping mechanisms. Dimethylsulfoxide activates the cytomegalovirus promoter in Chinese hamster ovary cells by promoting histone acetylation and the activation of p38 mitogen-activated protein kinase and nuclear factor kappaB (NFkappaB) signaling pathways, while 5-Aza-2'-deoxycytidine increases histone acetylation and activates the nuclear factor kappaB but not the p38 mitogen-activated protein kinase pathway. In H9c2-Fluc.3 cells, both agents promote demethylation of the cytomegalovirus promoter, and enhance its activity exclusively through activation of the nuclear factor kappaB pathway and to a lesser extent of the p38 mitogen-activated protein kinase pathway. Our findings suggest that suppression and activation of the cytomegalovirus promoter are cell type-specific. These results may be used for developing strategies to enhance the expression of transgenes and the production of recombinant proteins encoded by transgenes controlled by a cytomegalovirus promoter.


Assuntos
Azacitidina/análogos & derivados , Citomegalovirus/efeitos dos fármacos , Citomegalovirus/genética , Dimetil Sulfóxido/farmacologia , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Acetilação/efeitos dos fármacos , Animais , Azacitidina/farmacologia , Bovinos , Linhagem Celular , Cumarínicos/farmacologia , Cricetinae , Citomegalovirus/metabolismo , Metilação de DNA/efeitos dos fármacos , Decitabina , Relação Dose-Resposta a Droga , Histonas/metabolismo , Quinase I-kappa B/antagonistas & inibidores , Imidazóis/farmacologia , N-Acetilglucosaminiltransferases/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Piridinas/farmacologia , Fatores de Tempo , Transcrição Genética/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , beta-Galactosidase/biossíntese , beta-Galactosidase/genética , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
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