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1.
JMIR Res Protoc ; 13: e52882, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38457203

RESUMO

BACKGROUND: Despite strong and growing interest in ending the ongoing opioid health crisis, there has been limited success in reducing the prevalence of opioid addiction and the number of deaths associated with opioid overdoses. Further, 1 explanation for this is that existing interventions target those who are opiate-dependent but do not prevent opioid-naïve patients from becoming addicted. OBJECTIVE: Leveraging behavioral economics at the patient level could help patients successfully use, discontinue, and dispose of their opioid medications in an acute pain setting. The primary goal of this project is to evaluate the effect of the 3 versions of the Opioid Management for You (OPY) tool on measures of opioid use relative to the standard of care by leveraging a pragmatic randomized controlled trial (RCT). METHODS: A team of researchers from the Center for Learning Health System Sciences (CLHSS) at the University of Minnesota partnered with M Health Fairview to design, build, and test the 3 versions of the OPY tool: social influence, precommitment, and testimonial version. The tool is being built using the Epic Care Companion (Epic Inc) platform and interacts with the patient through their existing MyChart (Epic Systems Corporation) personal health record account, and Epic patient portal, accessed through a phone app or the MyChart website. We have demonstrated feasibility with pilot data of the social influence version of the OPY app by targeting our pilot to a specific cohort of patients undergoing upper-extremity procedures. This study will use a group sequential RCT design to test the impact of this important health system initiative. Patients who meet OPY inclusion criteria will be stratified into low, intermediate, and high risk of opiate use based on their type of surgery. RESULTS: This study is being funded and supported by the CLHSS Rapid Prospective Evaluation and Digital Technology Innovation Programs, and M Health Fairview. Support and coordination provided by CLHSS include the structure of engagement, survey development, data collection, statistical analysis, and dissemination. The project was initially started in August 2022. The pilot was launched in February 2023 and is still running, with the data last counted in August 2023. The actual RCT is planned to start by early 2024. CONCLUSIONS: Through this RCT, we will test our hypothesis that patient opioid use and diverted prescription opioid availability can both be improved by information delivery applied through a behavioral economics lens via sending nudges directly to the opioid users through their personal health record. TRIAL REGISTRATION: ClinicalTrials.gov NCT06124079; https://clinicaltrials.gov/study/NCT06124079. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/52882.

2.
Mol Cancer Ther ; 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38394685

RESUMO

Mucin-16 (MUC16) is a target for antibody-mediated immunotherapy in pancreatic ductal adenocarcinoma (PDAC) amongst other malignancies. The MUC16 specific monoclonal antibody AR9.6 has shown promise for PDAC immunotherapy and imaging. Here, we report the structural and biological characterization of the humanized AR9.6 antibody (huAR9.6). The structure of huAR9.6 was determined in complex with a MUC16 SEA (Sea urchin sperm, Enterokinase, Agrin) domain. Binding of huAR9.6 to recombinant, shed, and cell-surface MUC16 was characterized, and anti-PDAC activity was evaluated in vitro and in vivo. huAR9.6 bound a discontinuous, SEA domain epitope with an affinity of ~90 nM. Binding affinity depended on the specific SEA domain(s) present, and glycosylation enhanced affinity by 3-7-fold driven by favorable entropy and enthalpy and via distinct transition state thermodynamic pathways. Treatment with huAR9.6 reduced the in vitro growth, migration, invasion, and clonogenicity of MUC16-positive PDAC cells and patient-derived organoids (PDOs). HuAR9.6 blocked MUC16-mediated ErbB and AKT activation in PDAC cells, PDOs and patient-derived xenografts and induced antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity. More importantly, huAR9.6 treatment caused substantial PDAC regression in subcutaneous and orthotopic tumor models. The mechanism of action of huAR9.6 may depend on dense avid binding to homologous SEA domains on MUC16. The results of this study validate the translational therapeutic potential of huAR9.6 against MUC16-positive PDACs.

3.
Int J Mol Sci ; 23(10)2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35628269

RESUMO

Elevated levels of Mucin-16 (MUC16) in conjunction with a high expression of truncated O-glycans is implicated in playing crucial roles in the malignancy of pancreatic ductal adenocarcinoma (PDAC). However, the mechanisms by which such aberrant glycoforms present on MUC16 itself promote an increased disease burden in PDAC are yet to be elucidated. This study demonstrates that the CRISPR/Cas9-mediated genetic deletion of MUC16 in PDAC cells decreases tumor cell migration. We found that MUC16 enhances tumor malignancy by activating the integrin-linked kinase and focal adhesion kinase (ILK/FAK)-signaling axis. These findings are especially noteworthy in truncated O-glycan (Tn and STn antigen)-expressing PDAC cells. Activation of these oncogenic-signaling pathways resulted in part from interactions between MUC16 and integrin complexes (α4ß1), which showed a stronger association with aberrant glycoforms of MUC16. Using a monoclonal antibody to functionally hinder MUC16 significantly reduced the migratory cascades in our model. Together, these findings suggest that truncated O-glycan containing MUC16 exacerbates malignancy in PDAC by activating FAK signaling through specific interactions with α4 and ß1 integrin complexes on cancer cell membranes. Targeting these aberrant glycoforms of MUC16 can aid in the development of a novel platform to study and treat metastatic pancreatic cancer.


Assuntos
Antígeno Ca-125 , Carcinoma Ductal Pancreático , Quinase 1 de Adesão Focal , Integrina alfa4beta1 , Proteínas de Membrana , Neoplasias Pancreáticas , Antígeno Ca-125/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Quinase 1 de Adesão Focal/metabolismo , Humanos , Integrina alfa4beta1/metabolismo , Proteínas de Membrana/metabolismo , Hormônios Pancreáticos/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Polissacarídeos/metabolismo
4.
Protein Sci ; 31(5): e4300, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35481636

RESUMO

The COVID-19 pandemic caused by SARS-CoV-2 infection has led to socio-economic shutdowns and the loss of over 5 million lives worldwide. There is a need for the identification of therapeutic targets to treat COVID-19. SARS-CoV-2 spike is a target of interest for the development of therapeutic targets. We developed a robust SARS-CoV-2 S spike expression and purification protocol from insect cells and studied four recombinant SARS-CoV-2 spike protein constructs based on the original SARS-CoV-2 sequence using a baculovirus expression system: a spike protein receptor-binding domain that includes the SD1 domain (RBD) coupled to a fluorescent tag (S-RBD-eGFP), spike ectodomain coupled to a fluorescent tag (S-Ecto-eGFP), spike ectodomain with six proline mutations and a foldon domain (S-Ecto-HexaPro(+F)), and spike ectodomain with six proline mutations without the foldon domain (S-Ecto-HexaPro(-F)). We tested the yield of purified protein expressed from the insect cell lines Spodoptera frugiperda (Sf9) and Trichoplusia ni (Tni) and compared it to previous research using mammalian cell lines to determine changes in protein yield. We demonstrated quick and inexpensive production of functional glycosylated spike protein of high purity capable of recognizing and binding to the angiotensin converting enzyme 2 (ACE2) receptor. To further confirm functionality, we demonstrate binding of eGFP fused construct of the spike ectodomain (S-Ecto-eGFP) to surface ACE2 receptors on lung epithelial cells by flow cytometry analysis and show that it can be decreased by means of receptor manipulation (blockade or downregulation).


Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Enzima de Conversão de Angiotensina 2/genética , Animais , Humanos , Insetos/metabolismo , Mamíferos , Pandemias , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Prolina , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética
5.
Proc Natl Acad Sci U S A ; 119(18): e2115071119, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35476515

RESUMO

Activation of inhibitor of nuclear factor NF-κB kinase subunit-ß (IKKß), characterized by phosphorylation of activation loop serine residues 177 and 181, has been implicated in the early onset of cancer. On the other hand, tissue-specific IKKß knockout in Kras mutation-driven mouse models stalled the disease in the precancerous stage. In this study, we used cell line models, tumor growth studies, and patient samples to assess the role of IKKß and its activation in cancer. We also conducted a hit-to-lead optimization study that led to the identification of 39-100 as a selective mitogen-activated protein kinase kinase kinase (MAP3K) 1 inhibitor. We show that IKKß is not required for growth of Kras mutant pancreatic cancer (PC) cells but is critical for PC tumor growth in mice. We also observed elevated basal levels of activated IKKß in PC cell lines, PC patient-derived tumors, and liver metastases, implicating it in disease onset and progression. Optimization of an ATP noncompetitive IKKß inhibitor resulted in the identification of 39-100, an orally bioavailable inhibitor with improved potency and pharmacokinetic properties. The compound 39-100 did not inhibit IKKß but inhibited the IKKß kinase MAP3K1 with low-micromolar potency. MAP3K1-mediated IKKß phosphorylation was inhibited by 39-100, thus we termed it IKKß activation modulator (IKAM) 1. In PC models, IKAM-1 reduced activated IKKß levels, inhibited tumor growth, and reduced metastasis. Our findings suggests that MAP3K1-mediated IKKß activation contributes to KRAS mutation-associated PC growth and IKAM-1 is a viable pretherapeutic lead that targets this pathway.


Assuntos
MAP Quinase Quinase Quinase 1 , Neoplasias Pancreáticas , Humanos , Quinase I-kappa B/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Proteínas Serina-Treonina Quinases , Neoplasias Pancreáticas
6.
Eur J Med Chem ; 222: 113579, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34098465

RESUMO

Genetic models validated Inhibitor of nuclear factor (NF) kappa B kinase beta (IKKß) as a therapeutic target for KRAS mutation associated pancreatic cancer. Phosphorylation of the activation loop serine residues (S177, S181) in IKKß is a key event that drives tumor necrosis factor (TNF) α induced NF-κB mediated gene expression. Here we conducted structure activity relationship (SAR) study to improve potency and oral bioavailability of a quinoxaline analog 13-197 that was previously reported as a NFκB inhibitor for pancreatic cancer therapy. The SAR led to the identification of a novel quinoxaline urea analog 84 that reduced the levels of p-IKKß in dose- and time-dependent studies. When compared to 13-197, analog 84 was ∼2.5-fold more potent in TNFα-induced NFκB inhibition and ∼4-fold more potent in inhibiting pancreatic cancer cell growth. Analog 84 exhibited ∼4.3-fold greater exposure (AUC0-∞) resulting in ∼5.7-fold increase in oral bioavailability (%F) when compared to 13-197. Importantly, oral administration of 84 by itself and in combination of gemcitabine reduced p-IKKß levels and inhibited pancreatic tumor growth in a xenograft model.


Assuntos
Antineoplásicos/farmacologia , Quinase I-kappa B/antagonistas & inibidores , Neoplasias Pancreáticas/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Quinoxalinas/farmacologia , Ureia/farmacologia , Animais , 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 , Quinase I-kappa B/metabolismo , Camundongos , Estrutura Molecular , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Quinoxalinas/síntese química , Quinoxalinas/química , Relação Estrutura-Atividade , Ureia/análogos & derivados , Ureia/química
8.
Cancer Lett ; 503: 91-102, 2021 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-33485947

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is highly lethal. MUC4 (mucin4) is a heavily glycosylated protein aberrantly expressed in PDAC and promotes tumorigenesis via an unknown mechanism. To assess this, we genetically knocked out (KO) MUC4 in PDAC cells that did not express and did express truncated O-glycans (Tn/STn) using CRISPR/Cas9 technology. We found that MUC4 knockout cells possess less tumorigenicity in vitro and in vivo, which was further reduced in PDAC cells that express aberrant overexpression of truncated O-glycans. Also, MUC4KO cells showed a further reduction of epidermal growth factor receptors (ErbB) and their downstream signaling pathways in truncated O-glycan expressing PDAC cells. Tn-MUC4 specific 3B11 antibody inhibited MUC4-induced ErbB receptor and its downstream signaling cascades. MUC4 knockout differentially regulates apoptosis and cell cycle arrest in branched and truncated O-glycan expressing PDAC cells. Additionally, MUC4KO cells were found to be more sensitive to gemcitabine treatment. They possessed the upregulated expression of hENT1 and hCNT3 compared to parental cells, which were further affected in cells with aberrant O-glycosylation. Taken together, our results indicate that MUC4 enhances the malignant properties and gemcitabine resistance in PDAC tumors that aberrantly overexpress truncated O-glycans via altering ErbB/AKT signaling cascades and expression of nucleoside transporters, respectively.


Assuntos
Carcinoma Ductal Pancreático/patologia , Resistencia a Medicamentos Antineoplásicos , Mucina-4/genética , Neoplasias Pancreáticas/patologia , Polissacarídeos/metabolismo , Animais , Apoptose , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Transportador Equilibrativo 1 de Nucleosídeo/metabolismo , Receptores ErbB/metabolismo , Regulação Neoplásica da Expressão Gênica , Técnicas de Inativação de Genes , Humanos , Proteínas de Membrana Transportadoras/metabolismo , Camundongos , Mucina-4/metabolismo , Transplante de Neoplasias , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Gencitabina
9.
Mol Ther ; 29(4): 1557-1571, 2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-33359791

RESUMO

Aberrant expression of CA125/MUC16 is associated with pancreatic ductal adenocarcinoma (PDAC) progression and metastasis. However, knowledge of the contribution of MUC16 to pancreatic tumorigenesis is limited. Here, we show that MUC16 expression is associated with disease progression, basal-like and squamous tumor subtypes, increased tumor metastasis, and short-term survival of PDAC patients. MUC16 enhanced tumor malignancy through the activation of AKT and GSK3ß oncogenic signaling pathways. Activation of these oncogenic signaling pathways resulted in part from increased interactions between MUC16 and epidermal growth factor (EGF)-type receptors, which were enhanced for aberrant glycoforms of MUC16. Treatment of PDAC cells with monoclonal antibody (mAb) AR9.6 significantly reduced MUC16-induced oncogenic signaling. mAb AR9.6 binds to a unique conformational epitope on MUC16, which is influenced by O-glycosylation. Additionally, treatment of PDAC tumor-bearing mice with either mAb AR9.6 alone or in combination with gemcitabine significantly reduced tumor growth and metastasis. We conclude that the aberrant expression of MUC16 enhances PDAC progression to an aggressive phenotype by modulating oncogenic signaling through ErbB receptors. Anti-MUC16 mAb AR9.6 blocks oncogenic activities and tumor growth and could be a novel immunotherapeutic agent against MUC16-mediated PDAC tumor malignancy.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antígeno Ca-125/genética , Carcinogênese/genética , Carcinoma Ductal Pancreático/tratamento farmacológico , Receptores ErbB/genética , Proteínas de Membrana/genética , Adenocarcinoma/genética , Adenocarcinoma/imunologia , Adenocarcinoma/patologia , Animais , Anticorpos Monoclonais/farmacologia , Antígeno Ca-125/imunologia , Carcinogênese/imunologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/imunologia , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Progressão da Doença , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/imunologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/imunologia , Camundongos , Metástase Neoplásica , Isoformas de Proteínas/genética , Isoformas de Proteínas/imunologia , Transdução de Sinais
10.
bioRxiv ; 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32995771

RESUMO

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The initial interaction between Transmembrane Serine Protease 2 (TMPRSS2) primed SARS-CoV-2 spike (S) protein and host cell receptor angiotensin-converting enzyme 2 (ACE-2) is a pre-requisite step for this novel coronavirus pathogenesis. Here, we expressed a GFP-tagged SARS-CoV-2 S-Ectodomain in Tni insect cells. That contained sialic acid-enriched N- and O-glycans. Surface resonance plasmon (SPR) and Luminex assay showed that the purified S-Ectodomain binding to human ACE-2 and immunoreactivity with COVID-19 positive samples. We demonstrate that bromelain (isolated from pineapple stem and used as a dietary supplement) treatment diminishes the expression of ACE-2 and TMPRSS2 in VeroE6 cells and dramatically lowers the expression of S-Ectodomain. Importantly, bromelain treatment reduced the interaction between S-Ectodomain and VeroE6 cells. Most importantly, bromelain treatment significantly diminished the SARS-CoV-2 infection in VeroE6 cells. Altogether, our results suggest that bromelain or bromelain rich pineapple stem may be used as an antiviral against COVID-19. HIGHLIGHTS: Bromelain inhibits / cleaves the expression of ACE-2 and TMPRSS2Bromelain cleaves / degrades SARS-CoV-2 spike proteinBromelain inhibits S-Ectodomain binding and SARS-CoV-2 infection.

11.
J Cell Mol Med ; 23(10): 6885-6896, 2019 10.
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.


Assuntos
Transição Epitelial-Mesenquimal , Células-Tronco Neoplásicas/patologia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Polissacarídeos/metabolismo , Animais , Antígenos Glicosídicos Associados a Tumores/metabolismo , Carcinogênese/patologia , Linhagem Celular Tumoral , Proliferação de Células , Deleção de Genes , Humanos , Camundongos Nus , Modelos Biológicos , Chaperonas Moleculares/metabolismo , Invasividade Neoplásica , Metástase Neoplásica , Células-Tronco Neoplásicas/metabolismo , Análise de Sobrevida
12.
FEBS Lett ; 593(19): 2751-2761, 2019 10.
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.


Assuntos
Regulação para Baixo , Mucina-1/metabolismo , N-Acetilgalactosaminiltransferases/genética , Neoplasias Pancreáticas/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Mucina-1/química , Mucina-1/genética , N-Acetilgalactosaminiltransferases/metabolismo , Neoplasias Pancreáticas/genética , Regiões Promotoras Genéticas , Ligação Proteica , Fator de Transcrição Sp1/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Polipeptídeo N-Acetilgalactosaminiltransferase
13.
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.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Antimetabólitos Antineoplásicos/administração & dosagem , Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Linhagem Celular Tumoral , Cisplatino/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Sinergismo Farmacológico , Géis , Humanos , Camundongos , Camundongos Nus , Nanoestruturas , Platina/metabolismo , Polímeros/química , Gencitabina
14.
Int J Biochem Cell Biol ; 83: 1-14, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27939754

RESUMO

Generation of nitric oxide (NO) in cellular compartments acts in a redox-dependent manner to counteract oxidative stress either by directly acting as an antioxidant through scavenging superoxide anions (O2-), to form peroxynitrite (ONOO-) or acting as a signaling molecule, altering gene expression that triggers various physiological processes. However, the molecular mechanisms of macrophage activation and NO production leads to apoptosis and inflammation after 2-chloroethyl ethyl sulphide (CEES) exposure remains unclear. We showed that CEES exposure in macrophages increased the O2- production. Also CEES exposure transiently increases the NO production and ONOO- accumulation via expression of inducible NO synthase (iNOS). Simultaneously, CEES exposure caused a significant reduction in cellular antioxidants and modulate lipid peroxidation (LPO), and protein carbonylation (PC) reactions, which was correlated with the increased level of NO and ONOO- accumulation. Mechanistic studies showed the DNA damage, 8-oxoGDNA glycosylase (OGG1) down regulation and 8-hydroxydeoxyguanosine (8-OHdG) accumulations in DNA, which was also confirmed by phosphorylation of ATM, ATR and H2A.X. Elevated levels of NO/ONOO- plays an important role in apoptosis, and alteration of cell cycle regulatory proteins in macrophages after CEES exposure. Moreover, CEES exposure to macrophage cells enhanced the transcriptional activities of inflammatory mediators such as TNFα, IL-1α, ICAM, CX3CL1, CCL8, and CXCL10, which were linked with NO/ONOO- accumulation. These results showed a mechanistic explanation of how NO/ONOO- cooperate to conduct apoptosis and inflammatory signals in macrophages after CEES challenged. Further, the protective effects of NO/ONOO- inhibitors may provide the basis for the development of a therapeutic strategy to counteract exposure to CEES.


Assuntos
Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Gás de Mostarda/análogos & derivados , Óxido Nítrico/metabolismo , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Dano ao DNA , Humanos , Inflamação/etiologia , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Camundongos , Camundongos Pelados , Gás de Mostarda/toxicidade , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Ácido Peroxinitroso/metabolismo , Células RAW 264.7 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
15.
Contemp Clin Dent ; 5(4): 561-3, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25395781

RESUMO

Neural tumors located centrally in jaw bones are relatively rare compared with soft tissue neurofibromas. Less than 50 cases have been reported in the literature with a predilection for mandible. This article aims to elucidate a unique case of intraosseous neurofibroma of mandible in a 62-year-old edentulous female patient associated with facial asymmetry due to the swelling extending from the right body of mandible to left body of mandible. The uniqueness of this case is related to the age and extensiveness of this lesion. A review of clinical, radiographic, histological, and immunohistochemical features, and the surgical management pertaining to this case are discussed along with a review of the literature.

16.
J Hazard Mater ; 278: 236-49, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24976129

RESUMO

2-chloroethyl ethyl sulphide (CEES), a monofunctional analogue of sulfur mustard, is a strong vesicant and an alkylating chemical warfare agent. We studied the molecular mechanism of oxidative stress triggered signaling cascades in murine macrophages exposed to CEES with lipopolysaccharide (LPS). Exposure of CEES with specific dose of LPS stimulates oxidative stress caused increasing level of intracellular ROS and RNS, decreased antioxidant enzymes, increasing bimolecular damage, reduced cell viability, and cell cycle arrest. Synergistic exposure of CEES and LPS provoked significant increase in phosphorylation of MAPKs, Akt, tuberin, that down regulate OGG1 expression and 8-OHdG accumulations. Treatment with Akt and ERK1/2 inhibitors, the cells with constitutively active inhibiting activity of Akt and ERK1/2MAPK significant reduce CEES and LPS challenge tuberin but not the OGG1. In addition, the N-acetylcysteine inhibited ROS/RNS generation, elevation of antioxidants level, expression of ERK1/2, Akt, tuberin phosphorylation, resulted in deceased 8-OHdG accumulation and upregulation of OGG1 protein expression suggesting no involvement of Akt and ERK1/2MAPK pathways after CEES and LPS challenge. Collectively, our results indicate that exposure of CEES and LPS induces oxidative stress and the activation of tuberin, and 8-OHdG accumulation via upstream signaling pathways including Akt and ERK1/2MAPK pathway in macrophages but not the down regulation of OGG1.


Assuntos
Substâncias para a Guerra Química/toxicidade , DNA Glicosilases/metabolismo , Lipopolissacarídeos/toxicidade , Gás de Mostarda/análogos & derivados , Estresse Oxidativo/efeitos dos fármacos , Proteínas Supressoras de Tumor/metabolismo , 8-Hidroxi-2'-Desoxiguanosina , Animais , Apoptose/efeitos dos fármacos , Catalase/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Gás de Mostarda/toxicidade , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa
17.
Ann Plast Surg ; 72(1): 100-3, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23314188

RESUMO

OBJECTIVE: Perhaps the most vexing and exigent problem confronting head and neck cancer reconstruction is overcoming the impediments of collateral damage imposed by radiation therapy (XRT) on normal surrounding tissue. Radiation therapy is detrimental to bone and soft tissue repair resulting in an unacceptably high incidence of devastating wound healing complications as well as the associated morbidity of late pathologic fractures, reduced bone healing, and osteoradionecrosis. The consequences of XRT on bone vasculature, long known to be affected by radiation, have been poorly understood. The purpose of this study was to analyze the degree by which irradiation degrades existing bone vascularity using a powerful micro-computed tomography technique to attain highly precise quantitative metrics of the vascular tree. METHODS: Fourteen 400-g male Sprague-Dawley rats underwent 35 Gy of fractionated XRT at 7 Gy/d. The animals were euthanized after 28 days, and the left ventricle was fixed and injected with Microfil (MV-122; Flow Tech, Carver, Mass) contrast. Left hemimandibles were dissected and scanned using high-resolution micro-computed tomography (18-µm voxels). The vessel number, thickness, separation, connectivity, and vessel volume fraction were analyzed for the region of interest, defined to be the volume behind the third molar spanning a total distance of 5.1 mm. RESULTS: Stereologic analysis and subsequent analysis of variance test demonstrated a significant and quantifiable diminution in the irradiated vasculature when compared with control animals. The vessel volume fraction (0.016 vs 0.032, P ≤ 0.003) and vessel thickness (0.042 vs 0.067 mm, P ≤ 0.001) were markedly reduced. Interestingly, further analysis demonstrated no significant differences between vessel separation and vessel number. CONCLUSIONS: The results of our study specifically quantify the corrosive affects of XRT on the vasculature of the mandible. The data from this novel technique go even further and imply retention of blood vessels but a degradation of their quality and size. Further experiments can now be directed at therapeutic interventions to reverse this process and better understand the underlying mechanism of XRT-induced bone injury.


Assuntos
Mandíbula/irrigação sanguínea , Microvasos/efeitos da radiação , Microtomografia por Raio-X , Animais , Fracionamento da Dose de Radiação , Masculino , Mandíbula/diagnóstico por imagem , Mandíbula/efeitos da radiação , Microvasos/diagnóstico por imagem , Ratos , Ratos Sprague-Dawley
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