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1.
Toxicol Appl Pharmacol ; 491: 117066, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39128506

RESUMO

Paclitaxel (PTX) is a microtubule stabilizer that disrupts the normal cycle of microtubule depolymerization and repolymerization, leading to cell cycle arrest and cancer cell death. It is commonly used as a first-line chemotherapeutics for various malignancies, such as breast cancer, non-small cell lung cancer, and ovarian cancer. However, PTX chemotherapy is associated with common and serious side effects, including chemotherapy-induced peripheral neuropathy (CIPN). As cancer treatment advances and survival rates increase, the impact of CIPN on patients' quality of life has become more significant. To date, there is no effective treatment strategy for CIPN. Surtuin3 (SIRT3) is a nicotinamide adenine dinucleotide (NAD+) dependent protein deacetylase located on mitochondria. It transfers the acetyl group of the lysine side chain of acetylated substrate proteins to NAD+, producing deacetylated proteins to regulate mitochondrial energy metabolic processes. SIRT3 has been found to play an important role in various diseases, including aging, neurodegenerative diseases, cancer, heart disease, metabolic diseases, etc. However, the role of SIRT3 in CIPN is still unknown. This study found for the first time that activating SIRT3 helps to improve paclitaxel-induced CIPN. Nicotinamide riboside (NR) can protect dorsal root ganglion (DRG) mitochondria against oxidative damage caused by paclitaxel through activating SIRT3-MnSOD2 and SIRT3-Nrf2 pathway. Moreover, NR can enhance the anticancer activity of paclitaxel. Together, our research provides new strategy and candidate drug for the treatment of CIPN.


Assuntos
Niacinamida , Paclitaxel , Doenças do Sistema Nervoso Periférico , Compostos de Piridínio , Sirtuína 3 , Paclitaxel/toxicidade , Sirtuína 3/metabolismo , Animais , Compostos de Piridínio/farmacologia , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/prevenção & controle , Doenças do Sistema Nervoso Periférico/metabolismo , Niacinamida/análogos & derivados , Niacinamida/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/toxicidade , Camundongos , Humanos , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Masculino
2.
Sci Rep ; 14(1): 13503, 2024 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-38866831

RESUMO

The increasing prevalence of heart failure (HF) in ageing populations drives demand for echocardiography (echo). There is a worldwide shortage of trained sonographers and long waiting times for expert echo. We hypothesised that artificial intelligence (AI)-enhanced point-of-care echo can enable HF screening by novices. The primary endpoint was the accuracy of AI-enhanced novice pathway in detecting reduced LV ejection fraction (LVEF) < 50%. Symptomatic patients with suspected HF (N = 100, mean age 61 ± 15 years, 56% men) were prospectively recruited. Novices with no prior echo experience underwent 2-weeks' training to acquire echo images with AI guidance using the EchoNous Kosmos handheld echo, with AI-automated reporting by Us2.ai (AI-enhanced novice pathway). All patients also had standard echo by trained sonographers interpreted by cardiologists (reference standard). LVEF < 50% by reference standard was present in 27 patients. AI-enhanced novice pathway yielded interpretable results in 96 patients and took a mean of 12 min 51 s per study. The area under the curve (AUC) of the AI novice pathway was 0.880 (95% CI 0.802, 0.958). The sensitivity, specificity, positive predictive and negative predictive values of the AI-enhanced novice pathway in detecting LVEF < 50% were 84.6%, 91.4%, 78.5% and 94.1% respectively. The median absolute deviation of the AI-novice pathway LVEF from the reference standard LVEF was 6.03%. AI-enhanced novice pathway holds potential to task shift echo beyond tertiary centres and improve the HF diagnostic workflow.


Assuntos
Inteligência Artificial , Ecocardiografia , Insuficiência Cardíaca , Sistemas Automatizados de Assistência Junto ao Leito , Humanos , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/diagnóstico , Feminino , Ecocardiografia/métodos , Masculino , Pessoa de Meia-Idade , Idoso , Estudos Prospectivos , Volume Sistólico , Programas de Rastreamento/métodos
3.
Mol Cell Neurosci ; 125: 103848, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36948232

RESUMO

Astrocytes are key players in neuroinflammation. In response to central nervous system (CNS) injury or disease, astrocytes undergo reactive astrogliosis, which is characterized by increased proliferation, migration, and glial fibrillary acidic protein (GFAP) expression. Activation of the transcription factor nuclear factor-κB (NF-κB) and upregulation of downstream proinflammatory mediators in reactive astrocytes induce a proinflammatory phenotype in astrocytes, thereby exacerbating neuroinflammation by establishing an inflammatory loop. In this study, we hypothesized that excessive fibronectin (FN) derived from reactive astrocytes would induce this proinflammatory phenotype in astrocytes in an autocrine manner. We exogenously treated astrocytes with monomer FN, which can be incorporated into the extracellular matrix (ECM), to mimic plasma FN extravasated through a compromised blood-brain barrier in neuroinflammation. We also induced de novo synthesis and accumulation of astrocyte-derived FN through tumor necrosis factor-α (TNF-α) stimulation. The excessive FN deposition resulting from both treatments initiated reactive astrogliosis and triggered NF-κB signaling in the cultured astrocytes. In addition, inhibition of FN accumulation in the ECM by the FN inhibitor pUR4 strongly attenuated the FN- and TNF-α-induced GFAP expression, NF-κB activation, and proinflammatory mediator production of astrocytes by interrupting FN-ß1 integrin coupling and thus the inflammatory loop. In an in vivo experiment, intrathecal injection of pUR4 considerably ameliorated FN deposition, GFAP expression, and NF-κB activation in inflamed spinal cord, suggesting the therapeutic potential of pUR4 for attenuating neuroinflammation and promoting neuronal function restoration.


Assuntos
Fibronectinas , NF-kappa B , Humanos , NF-kappa B/metabolismo , Fibronectinas/genética , Fibronectinas/metabolismo , Integrina beta1/genética , Integrina beta1/metabolismo , Astrócitos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Células Cultivadas , Doenças Neuroinflamatórias , Gliose/metabolismo , Fenótipo
4.
Diagnostics (Basel) ; 12(12)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36553070

RESUMO

Background: Deep learning (DL) methods can noninvasively predict glioma subtypes; however, there is no set paradigm for the selection of network structures and input data, including the image combination method, image processing strategy, type of numeric data, and others. Purpose: To compare different combinations of DL frameworks (ResNet, ConvNext, and vision transformer (VIT)), image preprocessing strategies, magnetic resonance imaging (MRI) sequences, and numerical data for increasing the accuracy of DL models for differentiating glioma subtypes prior to surgery. Methods: Our dataset consisted of 211 patients with newly diagnosed gliomas who underwent preoperative MRI with standard and diffusion-weighted imaging methods. Different data combinations were used as input for the three different DL classifiers. Results: The accuracy of the image preprocessing strategies, including skull stripping, segment addition, and individual treatment of slices, was 5%, 10%, and 12.5% higher, respectively, than that of the other strategies. The accuracy increased by 7.5% and 10% following the addition of ADC and numeric data, respectively. ResNet34 exhibited the best performance, which was 5% and 17.5% higher than that of ConvNext tiny and VIT-base, respectively. Data Conclusions: The findings demonstrated that the addition of quantitatively numeric data, ADC images, and effective image preprocessing strategies improved model accuracy for datasets of similar size. The performance of ResNet was superior for small or medium datasets.

5.
Biochim Biophys Acta Gen Subj ; 1866(5): 130099, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35134491

RESUMO

OLA1 is a P-loop ATPase, implicated in centrosome duplication through the interactions with tumor suppressors BRCA1 and BARD1. Disruption of the interaction of OLA1 with BARD1 results in centrosome amplification. However, the molecular interplay and mechanism of the OLA1-BARD1 complex remain elusive. Here, we use a battery of biophysical, biochemical, and structural analyses to elucidate the molecular basis of the OLA1-BARD1 interaction. Our structural and enzyme kinetics analyses show this nucleotide-dependent interaction enhances the ATPase activity of OLA1 by increasing the turnover number (kcat). Unlike canonical GTPase activating proteins that act directly on the catalytic G domain, the BARD1 BRCT domain binds to the OLA1 TGS domain via a highly conserved BUDR motif. A cancer related mutation V695L on BARD1 is known to associate with centrosome abnormality. The V695L mutation reduces the BARD1 BRCT-mediated activation of OLA1. Crystallographic snapshot of the BRCT V695L mutant at 1.88 Å reveals this mutation perturbs the OLA1 binding site, resulting in reduced interaction. Altogether, our findings suggest the BARD1 BRCT domain serves as an ATPase activating protein to control OLA1 allosterically.


Assuntos
Adenosina Trifosfatases , Proteínas Supressoras de Tumor , Adenosina Trifosfatases/metabolismo , Ciclo Celular , Centrossomo/metabolismo , Proteínas Supressoras de Tumor/química , Ubiquitina-Proteína Ligases/metabolismo
6.
Cancer Med ; 11(3): 555-570, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34913612

RESUMO

BACKGROUND: Gastric diffuse large B-cell lymphoma (DLBCL) is often associated with Helicobacter pylori (H. pylori) infection. Those in the early stage could be treated with H. pylori eradication therapy, and are classified into a sensitive group and a resistant group. METHODS: Genome-wide miRNA and miRNA expression profiles were obtained from biopsy specimens of gastric DLBCL. MiRNAs and their targets as predictors of responses to H. pylori eradication therapy were identified through differential expression and pathway enrichment analysis, and further confirmed with transfection experiments in lymphoma cell lines of B-cell origin. RESULTS: Genome-wide miRNA and mRNA profiles showed miR-200 was associated with the sensitive group, and that the resistant group had higher levels of miR-155 and lower levels of DEPTOR (an inhibitor of mTOR) than the sensitive group. BJAB cells transfected with miR-155 also had lower DEPTOR and higher mTOR levels. Therefore, miR-155-mediated inhibition of DEPTOR with secondary activation of mTOR was a potential marker for resistance to H. pylori eradication therapy. In contrast, pathway enrichment analysis showed that Toll-like receptor 5 (TLR5), the receptor for bacterial flagellin, was a potential marker for sensitivity to H. pylori eradication therapy. In an independent series, stronger expression of pS6K1 (a direct target of mTOR) was associated with the resistant group and morphologic evidence of active gastritis was associated with the sensitive group. CONCLUSIONS: These findings showed that activation of the miR-155-DEPTOR pathway is a marker for resistance to H. pylori eradication therapy, and that histological evaluation of active gastritis might be used as a surrogate marker to predict responses to H. pylori eradication therapy in gastric DLBCL.


Assuntos
Gastrite , Infecções por Helicobacter , Helicobacter pylori , Linfoma Difuso de Grandes Células B , MicroRNAs , Neoplasias Gástricas , Gastrite/microbiologia , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/genética , Helicobacter pylori/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma não Hodgkin , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/microbiologia , Serina-Treonina Quinases TOR/metabolismo , Receptor 5 Toll-Like/metabolismo
7.
Biomedicines ; 8(9)2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32825464

RESUMO

In this study, the anti-tumor activity of ilimaquinone (IQ), a sesquiterpene quinone isolated from marine sponge Halichondria sp., in oral squamous cell carcinoma (OSCC) cells, was investigated. IQ suppressed the viability of the OSCC cell lines SCC4 and SCC2095 with IC50 values of 7.5 and 8.5 µM, respectively. Flow cytometric analysis demonstrated that IQ induced caspase-dependent apoptosis in SCC4 cells and modulated the expression of several cell growth-related gene products, including Akt, p38, Mcl-1, and p53. Notably, p53 knockdown caused higher resistance to IQ's anti-tumor activity. In addition, IQ increased reactive oxygen species generation, which was partially reversed by the addition of antioxidants. Furthermore, it triggered autophagy, as evidenced by acidic organelle formation and LC3B-II and Atg5 expression in SCC4 cells. Pretreatment with the autophagy inhibitor 3-methyladenine or chloroquine partially decreased IQ-induced apoptosis, suggesting that IQ induced protective autophagy. In summary, IQ has potential to be used in OSCC therapy.

8.
Biosens Bioelectron ; 164: 112320, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32479341

RESUMO

In this study we developed a uniform, large-area, layered graphene composite of graphene oxide/graphene (GO/G) for the detection of circulating miRNA-21, a reliable biomarker for early cancer diagnosis. We prepared this layered composite of GO/G through low-damage plasma treatment of bilayer G. The top layer of G was oxidized (i.e., atomic layer oxidation) to form a GO layer, which acted as the bio-receptor, while retaining the properties of the bottom layer of G, which acted as an electrical response medium. With this structure, we fabricated a simple chemiresistive biosensor that could detect miRNA-21. The electrical resistance of the sensor varied linearly (R2 = 0.986) with respect to concentrations of the target miRNA-21 in the range from 10 pM to 100 nM in phosphate-buffered saline (PBS); the limit of detection was 14.6 pM. Hall measurements revealed that the mobility and concentration of the hole carriers both decreased upon increasing the target concentration, leading to the measured increase in resistivity of our chemiresistive biosensor. Furthermore, the sensor could discriminate the complementary target miRNA-21 from its single- and four-base-mismatched counterparts and another non-complementary miRNA. The ability to detect miRNA-21 in human serum albumin and bovine serum albumin was almost identical to that in PBS.


Assuntos
Técnicas Biossensoriais , Grafite , MicroRNAs , Humanos , Soroalbumina Bovina
9.
Glob Heart ; 15(1): 22, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32489795

RESUMO

Introduction: Chest pain is a common symptom for cardiology referrals. The ACC-AHA guidelines recommend exercise stress electrocardiography (TMX) as the initial diagnostic test. However, the TMX only has moderate sensitivity and non-diagnostic cases may require further stress imaging studies. In this study we aimed to look at the feasibility of combining coronary artery calcium (CAC) score with TMX to refine risk stratification. This may be an alternative to stress imaging in cases of non low-risk TMX, with the added advantage of short time turnaround time and low radiation dose. Methods: A total of 145 patients who presented consecutively to the National Heart Centre Singapore with chest pain were included in this study. These were intermediate risk patients with an average Duke Clinical Score of 38.8%. All patients underwent both TMX and computed tomography scan of the coronary arteries (CTCA) which also includes CAC. The primary outcome was defined as obstructive coronary artery disease i.e. >50% left main artery stenosis and/or >70% stenosis in other epicardial arteries. Results: The combination of TMX and CAC was comparable to stress imaging in detecting obstructive coronary artery disease. When added to TMX, CAC has an integrated discriminative improvement of 74.1%, achieved an area under the curve of 0.974 and adjusted R2 of 0.670 in detecting the primary outcome. Conclusion: The strategy of combining TMX and CAC is feasible in clinical practice to refine risk stratification in outpatients with intermediate risk chest pain. The calcium score readout also further guides therapy for primary prevention. Highlights: Treadmill exercise is one of the first line tests for cardiac chest pain work up.Non diagnostic test treadmill results requires further adjunctive tests.Downstream stress imaging causes delay in time to diagnosis.Coronary artery calcium scoring needs minimal preparation with fast turnaround time.Addition of coronary artery calcium to treadmill performs comparably to stress imaging.This is a feasible alternative to risk stratify non diagnostic treadmill tests and guide therapy for primary prevention.


Assuntos
Cálcio/metabolismo , Dor no Peito/diagnóstico , Doença da Artéria Coronariana/diagnóstico , Vasos Coronários/diagnóstico por imagem , Teste de Esforço/métodos , Medição de Risco , Biomarcadores/metabolismo , Dor no Peito/epidemiologia , Dor no Peito/etiologia , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/metabolismo , Estudos Transversais , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Singapura/epidemiologia
10.
Circ Heart Fail ; 13(2): e006472, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32059630

RESUMO

BACKGROUND: There are multiple risk factors for heart failure, but contemporary temporal trends according to sex, socioeconomic status, and ethnicity are unknown. METHODS: Using a national UK general practice database linked to hospitalizations (1998-2017), 108 638 incident heart failure patients were identified. Differences in risk factors among patient groups adjusted for sociodemographic factors and age-adjusted temporal trends were investigated using logistic and linear regression. RESULTS: Over time, a 5.3 year (95% CI, 5.2-5.5) age difference between men and women remained. Women had higher blood pressure, body mass index, and cholesterol than men (P<0.0001). Ischemic heart disease prevalence increased for all to 2006 before reducing in women by 0.5% per annum, reaching 42.7% (95% CI, 41.7-43.6), but not in men, remaining at 57.7% (95% CI, 56.9-58.6; interaction P=0.002). Diabetes mellitus prevalence increased more in men than in women (interaction P<0.0001). Age between the most deprived (74.6 years [95% CI, 74.1-75.1]) and most affluent (79.9 [95% CI, 79.6-80.2]) diverged (interaction P<0.0001), generating a 5-year gap. The most deprived had significantly higher annual increases in comorbidity numbers (+0.14 versus +0.11), body mass index (+0.14 versus +0.11 kg/m2), and lower smoking reductions (-1.2% versus -1.7%) than the most affluent. Ethnicity trend differences were insignificant, but South Asians were overall 6 years and the black group 9 years younger than whites. South Asians had more ischemic heart disease (+16.5% [95% CI, 14.3-18.6]), hypertension (+12.5% [95% CI, 10.5-14.3]), and diabetes mellitus (+24.3% [95% CI, 22.0-26.6]), and the black group had more hypertension (+12.3% [95% CI, 9.7-14.8]) and diabetes mellitus (+13.1% [95% CI, 10.1-16.0]) but lower ischemic heart disease (-10.6% [95% CI, -13.6 to -7.6]) than the white group. CONCLUSIONS: Population groups show distinct risk factor trend differences, indicating the need for contemporary tailored prevention programs.


Assuntos
Disparidades nos Níveis de Saúde , Insuficiência Cardíaca/etnologia , Fatores Raciais , Classe Social , Determinantes Sociais da Saúde/etnologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Bases de Dados Factuais , Feminino , Insuficiência Cardíaca/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores Raciais/tendências , Fatores de Risco , Distribuição por Sexo , Determinantes Sociais da Saúde/tendências , Fatores de Tempo , Reino Unido/epidemiologia
11.
Molecules ; 23(12)2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30563166

RESUMO

Demethoxycurcumin (DMC), through a self-assembled amphiphilic carbomethyl-hexanoyl chitosan (CHC) nanomatrix has been successfully developed and used as a therapeutic approach to inhibit cisplatin-induced drug resistance by suppressing excision repair cross-complementary 1 (ERCC1) in non-small cell lung carcinoma cells (NSCLC). Previously, DMC significantly inhibited on-target cisplatin resistance protein, ERCC1, via PI3K-Akt-snail pathways in NSCLC. However, low water solubility and bioavailability of DMC causes systemic elimination and prevents its clinical application. To increase its bioavailability and targeting capacity toward cancer cells, a DMC-polyvinylpyrrolidone core phase was prepared, followed by encapsulating in a CHC shell to form a DMC-loaded core-shell hydrogel nanoparticles (DMC-CHC NPs). We aimed to understand whether DMC-CHC NPs efficiently potentiate cisplatin-induced apoptosis through downregulation of ERCC1 in NSCLC. DMC-CHC NPs displayed good cellular uptake efficiency. Dissolved in water, DMC-CHC NPs showed comparable cytotoxic potency with free DMC (dissolved in DMSO). A sulforhodamine B (SRB) assay indicated that DMC-CHC NPs significantly increased cisplatin-induced cytotoxicity by highly efficient intracellular delivery of the encapsulated DMC. A combination of DMC-CHC NPs and cisplatin significantly inhibited on-target cisplatin resistance protein, ERCC1, via the PI3K-Akt pathway. Also, this combination treatment markedly increased the post-target cisplatin resistance pathway including bax, and cytochrome c expressions. Thymidine phosphorylase (TP), a main role of the pyrimidine salvage pathway, was also highly inhibited by the combination treatment. The results suggested that enhancement of the cytotoxicity to cisplatin via administration of DMC-CHC NPs was mediated by down-regulation of the expression of TP, and ERCC1, regulated via the PI3K-Akt pathway.


Assuntos
Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/genética , Quitosana , Curcumina/análogos & derivados , Neoplasias Pulmonares/genética , Nanopartículas , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Cisplatino/farmacologia , Curcumina/administração & dosagem , Diarileptanoides , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/metabolismo , Microscopia Confocal , Nanopartículas/química , Nanopartículas/ultraestrutura , Proteínas Proto-Oncogênicas c-akt/metabolismo
12.
Case Rep Cardiol ; 2018: 8676572, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29670772

RESUMO

The growth in percutaneous transluminal devices has enabled operators to tackle more complex, native, and post-bypass surgery anatomy. However, complications such as coronary artery dissection, coronary perforation, retrograde aortic dissection, arrhythmias, and acute coronary syndrome still occur with resulting mortality rates of up to 4.2% in complex interventions. Perforation of the circumflex artery is of particular interest in view of its position and relation to the surrounding cardiac structures. This is a site of potential fluid collection, and as the left atrium is fixed to the parietal pericardium at the entry of the pulmonary veins, fluid in the oblique sinus can accumulate enough pressure to compress the left atrium and the coronary sinus. We present a case of left circumflex artery perforation which demonstrates the physiologic complications of coronary sinus and left atrial compression and the resultant functional mitral stenosis.

13.
Cancer Treat Rev ; 55: 128-135, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28363142

RESUMO

Gene-silencing miRNA and siRNA are emerging as attractive therapeutics with potential to suppress any genes, which could be especially useful in combination cancer therapy to overcome multidrug resistant (MDR) cancer. Nanomedicine aims to advance cancer treatment through functional nanocarriers that delivers one or more therapeutics to cancer tissue and cells with minimal off-target effects and suitable release kinetics and dosages. Although much effort has gone into developing circulating nanocarriers with targeting functionality for systemic administration, another alternative and straightforward approach is to utilize formulations to be administered directly to the site of action, such as pulmonary and intratumoral delivery. The combination of gene-silencing RNA with drugs in nanocarriers for localized delivery is emerging with promising results. In this review, the current progress and strategies for local co-administration of RNA and drug for synergistic effects and future potential in cancer treatment are presented and discussed. Key advances in RNA-drug anticancer synergy and localized delivery systems were combined with a review of the available literature on local co-administration of RNA and drug for cancer treatment. It is concluded that advanced delivery systems for local administration of gene-silencing RNA and drug hold potential in treatment of cancer, depending on indication. In particular, there are promising developments using pulmonary delivery and intratumoral delivery in murine models, but further research should be conducted on other local administration strategies, designs that achieve effective intracellular delivery and maximize synergy and feasibility for clinical use.


Assuntos
Antineoplásicos/uso terapêutico , Inativação Gênica , Terapia Genética , Neoplasias/genética , Neoplasias/terapia , RNA Interferente Pequeno/uso terapêutico , Terapia Combinada , Humanos , MicroRNAs/uso terapêutico , RNA Interferente Pequeno/administração & dosagem
14.
Acta Otolaryngol ; 137(6): 656-661, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27921462

RESUMO

CONCLUSIONS: Most neoplasms of the parapharyngeal space are benign. The transcervical surgical approach is the preferred procedure in most cases. Intra-operative endoscopic exploration offers a new surgical management technique to reduce operative complications and post-operative recurrence rates. OBJECTIVES: To present the authors' experience in the treatment of primary parapharyngeal space tumors with emphasis on surgical approaches and employment of endoscopy to detect residual tumors through conventional approaches. METHOD: One hundred and sixty-seven patients treated surgically over a 10-year period were retrospectively reviewed. A comparison of the surgical approaches in a relevant case series was also conducted. RESULTS: All of the patients underwent pre-operative imaging before surgery, and intra-operative endoscopic detection was selectively used for large, deep tumors. Complete resection of the tumor was used in 158 patients (95%), with a transcervical surgical approach applied in 144 cases (84%). Of 167 tumors, 150 (90%) were benign and 17 (10%) were malignant, with neurilemmoma/schwannoma as the most frequent pathology (42%). Surgical complications were reported in 26 patients (15%), most commonly unilateral paralysis of the vocal cords (6%). Two patients (1%) presented with recurrence, on average 2.5 years (range = 1-4 years) after initial excision, and the mean follow-up time was 3.8 years (range = 10 months-10 years).


Assuntos
Neoplasias de Cabeça e Pescoço/cirurgia , Procedimentos Cirúrgicos Otorrinolaringológicos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Endoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
15.
Eur J Pharm Biopharm ; 109: 165-173, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27793756

RESUMO

Lung cancer kills more humans than any other cancer and multidrug resistance (MDR) in cancer stem-like cells (CSC) is emerging as a reason for failed treatments. One concept that addresses this root cause of treatment failure is the utilization of nanoparticles to simultaneously deliver dual drugs to cancer cells with synergistic performance, easy to envision - hard to achieve. (1) It is challenging to simultaneously load drugs of highly different physicochemical properties into one nanoparticle, (2) release kinetics may differ between drugs and (3) general requirements for biomedical nanoparticles apply. Here self-assembled nanoparticles of amphiphilic carboxymethyl-hexanoyl chitosan (CHC) were shown to present nano-microenvironments enabling simultaneous loading of hydrophilic and hydrophobic drugs. This was expanded into a dual-drug nano-delivery system to treat lung CSC. CHC nanoparticles were loaded/chemically modified with the anticancer drug cisplatin and the MDR-suppressing Chinese herbal extract demethoxycurcumin, followed by biofunctionalization with CD133 antibody for enhanced uptake by lung CSC, all in a feasible one-pot preparation. The nanoparticles were characterized with regard to chemistry, size, zeta potential and drug loading/release. Biofunctionalized and non-functionalized nanoparticles were investigated for uptake by lung CSC. Subsequently the cytotoxicity of single and dual drugs, free in solution or in nanoparticles, was evaluated against lung CSC at different doses. From the dose response at different concentrations the degree of synergy was determined through Chou-Talalay's Plot. The biofunctionalized nanoparticles promoted synergistic effects between the drugs and were highly effective against MDR lung CSC. The efficacy and feasible one-pot preparation suggests preclinical studies using relevant disease models to be justified.


Assuntos
Quitosana/química , Cisplatino/administração & dosagem , Curcumina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares/metabolismo , Nanopartículas/química , Células A549 , Antígeno AC133/metabolismo , Antineoplásicos/administração & dosagem , Biomarcadores/metabolismo , Quitosana/análogos & derivados , Coloides/química , Curcumina/administração & dosagem , Diarileptanoides , Relação Dose-Resposta a Droga , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Resistência a Múltiplos Medicamentos , Medicamentos de Ervas Chinesas/administração & dosagem , Humanos , Cinética , Células-Tronco Neoplásicas/efeitos dos fármacos , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier
16.
World J Gastroenterol ; 21(13): 3960-9, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25852282

RESUMO

AIM: To examine the methylation levels of interleukin-1 receptor-associated kinase 3 (IRAK3) and GLOXD1 and their potential clinical applications in hepatocellular carcinoma (HCC). METHODS: mRNA expression and promoter methylation of IRAK3 and GLOXD1 in HCC cells were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and methylation-specific PCR (MSP), respectively. Using pyrosequencing results, we further established a quantitative MSP (Q-MSP) system for the evaluation of IRAK3 and GLOXD1 methylation in 29 normal controls and 160 paired HCC tissues and their adjacent nontumor tissues. We also calculated Kaplan-Meier survival curves to determine the applications of gene methylation in the prognosis of HCC. RESULTS: IRAK3 and GLOXD1 expression was partially restored in several HCC cell lines after treatment with 5-aza-2'-deoxycytidine (DNA methyltransferase inhibitor; 5DAC). A partial decrease in the methylated band was also observed in the HCC cell lines after 5DAC treatment. Using GLOXD1 as an example, we found a significant correlation between the data obtained from the methylation array and from pyrosequencing. The methylation frequency of IRAK3 and GLOXD1 in HCC tissues was 46.9% and 63.8%, respectively. Methylation of IRAK3 was statistically associated with tumor stage. Moreover, HCC patients with IRAK3 methylation had a trend toward poor 3-year disease-free survival (P < 0.05). CONCLUSION: IRAK3 and GLOXD1 were frequently methylated in HCC tissues compared to normal controls and nontumor tissues. IRAK3 methylation was associated with tumor stage and poor prognosis of patients. These data suggest that IRAK3 methylation is a novel prognostic marker in HCC.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Metilação de DNA , Quinases Associadas a Receptores de Interleucina-1/genética , Neoplasias Hepáticas/genética , Adulto , Idoso , Sequência de Bases , Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Feminino , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Regiões Promotoras Genéticas , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA
17.
Am J Pathol ; 185(5): 1487-99, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25907832

RESUMO

Nasal natural killer (NK) cell lymphoma (NNL) is an Epstein-Barr virus-associated lymphoma of cytotoxic NK cell origin. The Epstein-Barr virus-encoded miR-BART20-5p inhibits T-bet (TBX21), the master transcription factor of cytotoxic NK cells. To further explore the roles of miRNAs in NNLs, we measured the miRNA expression profiles of 36 NNLs. miR-21, miR-142-3p, miR-126, miR-451, and miR-494-3p were the top five miRNAs with the highest expression levels. By using pathway analysis, we identified associations between all of the five miRNAs with the PTEN-AKT-mTOR pathway, in which PTEN suppresses the oncogenic AKT, and mTOR mediates the oncogenic effects of AKT. YT and NK92 cells derived from NK cell lymphomas were used. miR-494-3p inhibited PTEN with secondary activation of AKT in NK92 cells, and miR-142-3p inhibited RICTOR, a key component of the mTOR complex, with secondary suppression of AKT in YT cells. Significantly, T-bet inhibited the PTEN-AKT-mTOR/RICTOR pathway through induction of PTEN and suppression of RICTOR. Therefore, a molecular circuit of T-bet, PTEN, AKT, and RICTOR is regulated by miR-BART20-5p, miR-494-3p, and miR-142-3p. This circuit is involved in the pathogenesis of NNL. Hence, antagomirs to miR-BART20-5p or miR-494-3p, miR-142-3p mimics, or AKT inhibitors may be useful in NNL therapy.


Assuntos
Regulação Neoplásica da Expressão Gênica/genética , Células Matadoras Naturais/patologia , Linfoma Extranodal de Células T-NK/genética , MicroRNAs/genética , Transdução de Sinais/genética , Western Blotting , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Infecções por Vírus Epstein-Barr/complicações , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Linfoma Extranodal de Células T-NK/metabolismo , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína Companheira de mTOR Insensível à Rapamicina , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Transfecção
18.
J Biol Chem ; 290(23): 14302-13, 2015 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-25903129

RESUMO

Glucagon-like peptide-1 (GLP-1) analogs are approved for treatment of type 2 diabetes and are in clinical trials for disorders including neurodegenerative diseases. GLP-1 receptor (GLP-1R) is expressed in many peripheral and neuronal tissues and is activated by circulating GLP-1. Other than food intake, little is known about factors regulating GLP-1 secretion. Given a normally basal circulating level of GLP-1, knowledge of mechanisms regulating GLP-1R signaling, which has diverse functions in extrapancreatic tissues, remains elusive. In this study, we found that the potency of GLP-1, not exendin 4, is specifically enhanced by the endocannabinoid-like lipids oleoylethanolamide (OEA) and 2-oleoylglycerol but not by stearoylethanolamide (SEA) or palmitoylethanolamide. 9.2 µM OEA enhances the potency of GLP-1 in stimulating cAMP production by 10-fold but does not affect its receptor binding affinity. OEA and 2-oleoylglycerol, but not SEA, bind to GLP-1 in a dose-dependent and saturable manner. OEA but not SEA promoted GLP-1(7-36) amide to trypsin inactivation in a dose-dependent and saturable manner. Susceptibility of GLP-1(7-36) amide to trypsin inactivation is increased 40-fold upon binding to OEA but not to SEA. Our findings indicate that OEA binds to GLP-1(7-36) amide and enhances the potency that may result from a conformational change of the peptide. In conclusion, modulating potency of GLP-1 by physiologically regulated endocannabinoid-like lipids allows GLP-1R signaling to be regulated spatiotemporally at a constant basal GLP-1 level.


Assuntos
Peptídeo 1 Semelhante ao Glucagon/metabolismo , Glicerídeos/metabolismo , Ácidos Oleicos/metabolismo , Receptores de Glucagon/metabolismo , Transdução de Sinais , Animais , Linhagem Celular Tumoral , AMP Cíclico/metabolismo , Endocanabinoides , Receptor do Peptídeo Semelhante ao Glucagon 1 , Humanos , Ratos
19.
Mol Pharm ; 12(4): 1242-9, 2015 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-25760774

RESUMO

Targeting controlled release core-shell nanocarriers with the potential to overcome multidrug resistant (MDR) lung cancer were prepared based on demethoxycurcumin (DMC) loaded amphiphilic chitosan nanoparticles coated with an anti-EGFR antibody layer. The nanocarriers were characterized with regard to size with dynamic light scattering, SEM, and TEM. The characterization confirmed the nanocarriers to have a surface coating of the anti-EGFR antibody and a final size excellently suited for circulating targeting nanocarriers, i.e., <200 nm in diameter. In vitro drug release revealed extended quasi-Fickian release from the nanocarriers, with the anti-EGFR layer further reducing the release rate. Cell culture experiments using normoxic and MDR hypoxic cells overexpressing EGFR confirmed improved DMC delivery for anti-EGFR coated particles and revealed that the DMC was delivered to the cytoplasmic region of the cells, forming nanoprecipitates in lysosomes and endosomes. The effective endocytosis and targeting of the core-shell nanoparticles resulted in the nanocarriers achieving high cytotoxicity also against MDR cells. The therapeutic potential was further confirmed in an A549 xenograft lung tumor mouse model, where DMC loaded core-shell nanocarriers achieved about 8-fold reduction in tumor volume compared with control group over the 8 weeks of the investigation. Both in vitro and in vivo data suggest the anti-EGFR coated core-shell nanocarriers as highly promising for treatment of hypoxic MDR cancers, especially for non-small cell lung cancer.


Assuntos
Quitosana/química , Curcumina/análogos & derivados , Portadores de Fármacos , Nanopartículas/química , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Curcumina/química , Citoplasma/metabolismo , Diarileptanoides , Sistemas de Liberação de Medicamentos , Receptores ErbB/metabolismo , Humanos , Concentração Inibidora 50 , Luz , Neoplasias Pulmonares/tratamento farmacológico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanomedicina , Transplante de Neoplasias , Espalhamento de Radiação
20.
BMC Cancer ; 14: 608, 2014 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-25149057

RESUMO

BACKGROUND: The role of postoperative adjuvant treatment for sinonasal malignant melanoma remains unclear. This study evaluates the impact of three different surgical and postoperative adjuvant treatment modalities: surgery alone(open and endoscopic approaches), surgery plus radiotherapy and surgery, radiotherapy plus chemotherapy on survival of patients with primary sinonasal malignant melanoma (SMM). METHODS: The data of 69 patients who underwent primary surgical treatments at Eye & ENT hospital of Fudan University between January 1st, 2000 and December 31st, 2010 were retrospectively reviewed. Survival comparison of different surgical and postoperative adjuvant treatment modalities (surgery alone, surgery plus radiotherapy and surgery, radiotherapy plus chemotherapy), as well as survival comparison between open and endoscopic surgical approaches were performed. Curves depicting survival were performed using Kaplan-Meier method. Statistical analysis was performed using log-rank test software SPSS19 and p < .05 is considered as statistically significant. RESULTS: The median overall survival time was found to be 18 months for surgery alone (27 cases), 32 months for surgery plus radiotherapy (24 cases), 42 months for surgery, radiotherapy plus chemotherapy (18 cases). The 3 and 5 year survival rates for groups mentioned above were 14.8% and 5.6%, 45.1% and 31.6%, 55% and 32.1%, respectively. Statistical significances were found not only between surgery alone and surgery plus radiotherapy treatment group (P = 0.012), but also surgery alone and surgery, radiotherapy plus chemotherapy group (P = 0.002). There was no statistically significant survival difference found between the two different surgical approaches (41 cases for open approach and 28 cases for endoscopic approach). CONCLUSIONS: Sinonasal malignant melanoma is a disease with a poor prognosis. Patients who underwent surgery plus radiotherapy or surgery, radiotherapy plus chemotherapy had better survival outcomes than those underwent surgery alone. Endoscopic approach provided similar survival outcome as an open approach.


Assuntos
Melanoma/terapia , Neoplasias dos Seios Paranasais/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimioterapia Adjuvante , Terapia Combinada , Feminino , Humanos , Masculino , Melanoma/mortalidade , Melanoma/cirurgia , Pessoa de Meia-Idade , Neoplasias dos Seios Paranasais/mortalidade , Neoplasias dos Seios Paranasais/cirurgia , Radioterapia Adjuvante , Estudos Retrospectivos , Análise de Sobrevida , Taxa de Sobrevida , Resultado do Tratamento
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