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1.
J Mater Sci Mater Med ; 33(10): 72, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36195780

RESUMO

Hepatocellular carcinoma is a common type of cancer associated with a high mortality rate. Among several bioactive compounds, Murrayafoline A (MuA) has been proved as a bio substance that exhibits great potentials in treating liver cancer. In order to overcome the high cytotoxicity and low solubility of MuA, a delivery system based on nanocarriers is necessary to deliver MuA towards the desired target. In the present study, 18ß-glycyrrhetinic acid (GA), which is known as a ligand for liver targeting, was used to construct the cholesterol-poly (ethylene glycol)-glycyrrhetinic acid (GA-PEG-Chol) conjugate and liposome for MuA administration. The compound was then examined for therapeutic efficacy and safety in HUVEC and HepG2 cells in 2D and 3D cell cultures. Results have shown that MuA-loaded liposomes had IC50 value of 2 µM in HepG2 and had the cytosolic absorption of 8.83 ± 0.97 ng/105 cells, while The IC50 value of MuA-loaded liposomes in HUVEC cell lines was 15 µM and the the cytosolic absorption was recorded as 3.62 ± 0.61 cells. The drug test on the 3D cancer sphere platform of the HepG2 cancer sphere showed that MuA-loaded GA liposomes had the highest efficacy at a concentration of 100 µg/mL. In short, these results suggest that MuA-loaded GA liposomes have the potential for maintenance drug delivery and liver targeting.


Assuntos
Carcinoma Hepatocelular , Ácido Glicirretínico , Neoplasias Hepáticas , Alcaloides , Carbazóis , Carcinoma Hepatocelular/tratamento farmacológico , Colesterol , Ácido Glicirretínico/uso terapêutico , Células Hep G2 , Humanos , Ligantes , Lipossomos , Neoplasias Hepáticas/tratamento farmacológico
2.
Cancer Sci ; 113(8): 2716-2726, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35657693

RESUMO

Lysosomes function as the digestive system of a cell and are involved in macromolecular recycling, vesicle trafficking, metabolic reprogramming, and progrowth signaling. Although quality control of lysosome biogenesis is thought to be a potential target for cancer therapy, practical strategies have not been established. Here, we show that lysosomal membrane integrity supported by lysophagy, a selective autophagy for damaged lysosomes, is a promising therapeutic target for glioblastoma (GBM). In this study, we found that ifenprodil, an FDA-approved drug with neuromodulatory activities, efficiently inhibited spheroid formation of patient-derived GBM cells in a combination with autophagy inhibition. Ifenprodil increased intracellular Ca2+ level, resulting in mitochondrial reactive oxygen species-mediated cytotoxicity. The ifenprodil-induced Ca2+ elevation was due to Ca2+ release from lysosomes, but not endoplasmic reticulum, associated with galectin-3 punctation as an indicator of lysosomal membrane damage. As the Ca2+ release was enhanced by ATG5 deficiency, autophagy protected against lysosomal membrane damage. By comparative analysis of 765 FDA-approved compounds, we identified another clinically available drug for central nervous system (CNS) diseases, amoxapine, in addition to ifenprodil. Both compounds promoted degradation of lysosomal membrane proteins, indicating a critical role of lysophagy in quality control of lysosomal membrane integrity. Importantly, a synergistic inhibitory effect of ifenprodil and chloroquine, a clinically available autophagy inhibitor, on spheroid formation was remarkable in GBM cells, but not in nontransformed neural progenitor cells. Finally, chloroquine dramatically enhanced effects of the compounds inducing lysosomal membrane damage in a patient-derived xenograft model. These data demonstrate a therapeutic advantage of targeting lysosomal membrane integrity in GBM.


Assuntos
Glioblastoma , Glioma , Autofagia , Cloroquina/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Glioma/tratamento farmacológico , Glioma/metabolismo , Humanos , Lisossomos/metabolismo , Macroautofagia
3.
Technol Cancer Res Treat ; 21: 15330338221080941, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35379053

RESUMO

Background: The androgen receptor (AR) has recently emerged as a useful marker for the more favorable prognosis and better outcomes among women with estrogen receptor (ER) + ve breast cancer (BC) and the further refinement of BC subtype. Furthermore, AR expression in ER - ve tumors has a particular prognostic significance. Additionally, the ratio of nuclear AR to ER may critically have an influence on tumor biology and respond to endocrine therapy. Purpose: To define the AR expression and AR:ER ratio, and explored their correlation with the clinicopathological features, prognosis, and survival outcomes in the various subclasses of invasive BC. Methods: The current study was conducted on 522 BC patients who had surgical operations, without neoadjuvant chemotherapy by applying a retrospective cohort analysis. The clinicopathological characteristics were recorded. Immunohistochemical staining was performed on AR, ER, PR, HER2, and Ki67. Expression of AR was paired into different immunophenotypes for analysis with clinicopathological features and survival. All BC patients' survival was analyzed using Kaplan-Meier and log-rank models. Results: The presence of AR was detected in 65.3%. Positive AR, the ratio of AR:ER<2, luminal androgen receptor (LAR) + and AR + HER2 + immunophenotypes were significantly associated with better prognostic features. AR:ER<2 was observed in the prolonged overall survival (OS) and disease-free survival (DFS) (87.9 and 86.2%, respectively) compared to AR:ER≥2 (25.0% in both) (P < .001). In contrast, in HR + ve BCs, the AR expression was not significantly correlated with survival. The multivariate model revealed that the ratio of nuclear AR to ER remained as an independent prognostic variable. Conclusion: The AR expression had a distinct OS and DFS. The AR:ER ratio is an independent indicator for predicting the OS and DFS of BC patients in both univariate and multivariate analyses.


Assuntos
Neoplasias da Mama , Receptores de Estrogênio , Androgênios , Neoplasias da Mama/patologia , Estudos de Coortes , Feminino , Humanos , Receptores Androgênicos/genética , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Estudos Retrospectivos , Vietnã
4.
Int J Clin Exp Pathol ; 14(3): 322-337, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33786149

RESUMO

BACKGROUND: The Bhagarva surrogate molecular subtype definitions classify invasive breast cancer into seven the different subgroups based on immunohistochemical (IHC) criteria according to expression levels of markers as ER, PR, HER2, EGFR and/or basal cytokeratin (CK5/6) which are different in prognosis and responsiveness to adjuvant therapy. PURPOSE: The present study aimed to classify primary breast cancers and directly compares the prognostic significance of the intrinsic subtypes. METHODS: The current study was conducted on 522 breast cancer patients who had surgery, but had not received neoadjuvant chemotherapy, from 2011 to 2014. The clinicopathologic characteristics were recorded. IHC staining was performed for ER, PR, HER2, Ki67, CK5/6, EGFR and D2-40 markers. All breast cancer patients were stratified according to Bhagarva criteria. The followed-up patients' survival was analyzed by using Kaplan-Meier and Log-Rank models. RESULTS: The luminal A (LUMA) was observed at the highest rate (32.5%). Non-basal-like triple negative phenotype (TNB-) and Luminal A HER2-Hybrid (LAHH) were the least common (3.3% in both). LUMA and luminal B (LUMB) were significantly associated with better prognostic features compared to HER2, basal-like triple negative phenotype (TNB+) and TNB-. Statistically significant differences were demonstrated between overall survival (OS), disease-free survival (DFS) and molecular subtypes (P<0.05), of which LUMB and LUMA had the highest rate of OS and DFS being 97.2 and 93.7%; and 97.2 and 90.5%, respectively. Conversely, HER2 revealed the worst prognosis with the lowest prevalence of OS and DFS (72.5 and 69.9%, respectively). CONCLUSION: The molecular subtypes had a distinct OS and DFS. The intrinsic stratification displayed inversely to clinicopathological features in breast cancer.

5.
J Electron Mater ; 50(4): 1942-1948, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33519044

RESUMO

Ni-doped TiO2 nanoparticles have been synthesized by a modified sol-gel method. The crystal phase composition, particle size, and magnetic and optical properties of the samples were comprehensively examined using x-ray diffraction analysis, transmission electron microscopy, Brunauer-Emmett-Teller surface area analysis, Raman spectroscopy, magnetization measurements, and ultraviolet-visible (UV-Vis) absorption techniques. The results showed that the prepared Ni-doped TiO2 samples sintered at 400°C crystallized completely in anatase phase with average particle size in the range from 8 nm to 10 nm and presented broad visible absorption. The bactericidal efficiency of TiO2 was effectively enhanced by Ni doping, with an optimum Ni doping concentration of 6% (x = 0.06), at which 95% of Escherichia coli were killed after just 90 min of irradiation. Density functional theory (DFT) calculations revealed good agreement with the experimental data. Moreover, the Ni dopant induced magnetic properties in TiO2, facilitating its retrieval using a magnetic field after use, which is an important feature for photocatalytic applications.

6.
Technol Cancer Res Treat ; 19: 1533033820983081, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33357134

RESUMO

BACKGROUND: Aberrant of p53 and Bcl2 genes cause changes in the quantity and quality of their proteins and contribute to the pathogenesis of some cancer types including breast cancer. Expression of p53 and Bcl2 were associated to adverse clinical outcomes in breast cancer. PURPOSE: To predict the survival outcomes of invasive breast cancer in Vietnam, using immunohistochemical expression of p53, Bcl2 proteins. METHODS: The current study was conducted on 526 breast cancer patients who had surgical operations, but had not received neo-adjuvant chemotherapy, from 2011 to 2014. The clinicopathological characteristics were recorded. Immunohistochemical staining was performed on p53, Bcl2 markers. Expression of p53 and Bcl2 were paired into different immunophenotypes for analysis with clinicopathological characteristics and survival. All breast cancer patients' survival were analyzed by using Kaplan-Meier and Log-Rank models. RESULTS: The presence of p53 protein was detected in 44.1%. Positive p53, and p53+Bcl2- immunophenotype were significantly associated with poorer prognostic features. In contrast, the positive Bcl2 protein accounted on 57.6%, and combination of p53-Bcl2+ were strong correlated with better clinicopathological parameters. Bcl2 positivity was observed in higher than the negative Bcl2 in the five-year OS (Overall survival) proportion (91.2 vs 79.4%, respectively) (p < 0.05). Multivariate analysis revealed that the expression of p53, Bcl2 or combinations of these 2 proteins was no longer remained as an independent prognostic variable. CONCLUSION: The Bcl2 positivity had a distinct OS and DFS (Disease free survival). The expression of p53 and Bcl2 are inversely correlated to clinical outcomes in breast cancer.


Assuntos
Biomarcadores Tumorais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Feminino , Humanos , Imuno-Histoquímica , Imunofenotipagem , Hibridização in Situ Fluorescente , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Proteínas Proto-Oncogênicas c-bcl-2/genética , Estudos Retrospectivos , Proteína Supressora de Tumor p53/genética , Vietnã/epidemiologia , Adulto Jovem
7.
Cancer Control ; 27(1): 1073274820968883, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33136444

RESUMO

BACKGROUND: Tumor budding (Bd) has been demonstrated to be a promising prognostic factor in many carcinomas and in gastric cancer. It may represent an optimal additional parameter that is helpful for risk stratification in gastric adenocarcinoma. Hence, the present research was designed to predict the survival outcomes of gastric cancer in Vietnam, applying the tumor budding criteria of the International Tumor Budding Consensus Conference (ITBCC) 2016. METHODS: The present study was conducted on 109 gastric cancer patients who underwent surgery but did not receive neo-adjuvant chemotherapy from 2012 to 2015. The patients' clinicopathological features were recorded. Bd was evaluated according to the 2016 ITBCC criteria and classified as Bd1 (0-4 buds), Bd2 (5-9 buds), and Bd3 (≥10 buds) grades, in addition to being categorized into 2 main Bd groups: low (<10 buds) and high (≥10 buds) Bd. Kaplan-Meier and log-rank models were applied to analyze survival proportions. RESULTS: Of all the patients, 22.9% were classified as Bd1, 31.2% as Bd2, and 45.9% as Bd3 grades. Furthermore, 54.1% patients were categorized into the low and 45.9% into the high Bd groups. Patients with Bd1 and Bd2 grades (the low Bd group) exhibited the best prognosis, with 5-year overall survival (OS) rates of 85.7%, 90.8%, and90.3%, respectively. Patients with Bd3 grade (the high Bd group exhibited the worst prognosis, and none of them lived for 5 years (p < 0.001). Similar to OS rates, disease-free survival (DFS) rates markedly reduced from the Bd1 to Bd3 grade: Bd1, 95.0%; Bd2, 84.7%; and Bd3, 0% (p < 0.001). CONCLUSION: Patients with different gastric cancer Bd grades exhibited significantly different OS and DFS rates. The present study findings suggest that the ITBCC criteria can be used to stratify Bd for the treatment and prognosis of gastric cancer patients in Vietnam.


Assuntos
Carcinoma/mortalidade , Recidiva Local de Neoplasia/epidemiologia , Neoplasias Gástricas/mortalidade , Estômago/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Capecitabina/uso terapêutico , Carcinoma/patologia , Carcinoma/terapia , Quimioterapia Adjuvante/métodos , Intervalo Livre de Doença , Feminino , Seguimentos , Gastrectomia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Oxaloacetatos/uso terapêutico , Prognóstico , Estudos Retrospectivos , Medição de Risco/métodos , Estômago/cirurgia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/terapia , Vietnã/epidemiologia
8.
Cancer Sci ; 109(8): 2497-2508, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29902340

RESUMO

Autophagy plays a critical role in tumorigenesis, but how autophagy contributes to cancer cells' responses to chemotherapeutics remains controversial. To investigate the roles of autophagy in malignant gliomas, we used CRISPR/CAS9 to knock out the ATG5 gene, which is essential for autophagosome formation, in tumor cells derived from patients with glioblastoma. While ATG5 disruption inhibited autophagy, it did not change the phenotypes of glioma cells and did not alter their sensitivity to temozolomide, an agent used for glioblastoma patient therapy. Screening of an anticancer drug library identified compounds that showed greater efficacy to ATG5-knockout glioma cells compared to control. While several selected compounds, including nigericin and salinomycin, remarkably induced autophagy, potent autophagy inducers by mTOR inhibition did not exhibit the ATG5-dependent cytoprotective effects. Nigericin in combination with ATG5 deficiency synergistically suppressed spheroid formation by glioma cells in a manner mitigated by Ca2+ chelation or CaMKK inhibition, indicating that, in combination with autophagy inhibition, calcium-mobilizing compounds contribute to efficient anticancer therapeutics. ATG5-knockout cells treated with nigericin showed increased mitochondria-derived reactive oxygen species and apoptosis compared to controls, indicating that autophagy protects glioma cells from mitochondrial reactive oxygen species-mediated damage. Finally, using a patient-derived xenograft model, we demonstrated that chloroquine, a pharmacological autophagy inhibitor, dramatically enhanced the efficacy of compounds selected in this study. Our findings propose a novel therapeutic strategy in which calcium-mobilizing compounds are combined with autophagy inhibitors to treat patients with glioblastoma.


Assuntos
Autofagia/efeitos dos fármacos , Cálcio/metabolismo , Glioma/tratamento farmacológico , Glioma/metabolismo , Animais , Apoptose/efeitos dos fármacos , Proteína 5 Relacionada à Autofagia/metabolismo , Linhagem Celular Tumoral , Cloroquina/uso terapêutico , Dacarbazina/análogos & derivados , Dacarbazina/uso terapêutico , Feminino , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Temozolomida
9.
Biochem Biophys Res Commun ; 495(1): 1129-1135, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29175333

RESUMO

The mammalian target of rapamycin (mTOR) complex 1 (mTORC1) senses a cell's energy status and environmental levels of nutrients and growth factors. In response, mTORC1 mediates signaling that controls protein translation and cellular metabolism. Although mTORC1 plays a critical role in hematopoiesis, it remains unclear which upstream stimuli regulate mTORC1 activity in the context of hematopoietic stem cells (HSC) maintenance in vivo. In this study, we investigated the function of Rheb, a critical regulator of mTORC1 activity controlled by the PI3K-AKT-TSC axis, both in HSC maintenance in mice at steady-state and in HSC-derived hematopoiesis post-transplantation. In contrast to the severe hematopoietic dysfunction caused by Raptor deletion, which completely inactivates mTORC1, Rheb deficiency in adult mice did not show remarkable hematopoietic failure. Lack of Rheb caused abnormalities in myeloid cells but did not have impact on hematopoietic regeneration in mice subjected to injury by irradiation. As previously reported, Rheb deficiency resulted in defective HSC-derived hematopoiesis post-transplantation. However, while Raptor is essential for HSC competitiveness in vivo, Rheb is dispensable for HSC maintenance under physiological conditions, indicating that the PI3K-AKT-TSC pathway does not contribute to mTORC1 activity for sustaining HSC self-renewal activity at steady-state. Thus, the various regulatory elements that impinge upstream of mTORC1 activation pathways are differentially required for HSC homeostasis in vivo.


Assuntos
Autorrenovação Celular/fisiologia , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/fisiologia , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteína Enriquecida em Homólogo de Ras do Encéfalo/metabolismo , Proteína Regulatória Associada a mTOR/metabolismo , Animais , Células Cultivadas , Camundongos , Camundongos Endogâmicos C57BL
10.
Sci Rep ; 7(1): 11442, 2017 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-28900302

RESUMO

Hematopoietic stem cells (HSCs) in a steady state can be efficiently purified by selecting for a combination of several cell surface markers; however, such markers do not consistently reflect HSC activity. In this study, we successfully enriched HSCs with a unique stemness-monitoring system using a transgenic mouse in which green florescence protein (GFP) is driven by the promoter/enhancer region of the nucleostemin (NS) gene. We found that the phenotypically defined long-term (LT)-HSC population exhibited the highest level of NS-GFP intensity, whereas NS-GFP intensity was strongly downregulated during differentiation in vitro and in vivo. Within the LT-HSC population, NS-GFPhigh cells exhibited significantly higher repopulating capacity than NS-GFPlow cells. Gene expression analysis revealed that nine genes, including Vwf and Cdkn1c (p57), are highly expressed in NS-GFPhigh cells and may represent a signature of HSCs, i.e., a stemness signature. When LT-HSCs suffered from remarkable stress, such as transplantation or irradiation, NS-GFP intensity was downregulated. Finally, we found that high levels of NS-GFP identified HSC-like cells even among CD34+ cells, which have been considered progenitor cells without long-term reconstitution ability. Thus, high NS-GFP expression represents stem cell characteristics in hematopoietic cells, making this system useful for identifying previously uncharacterized HSCs.


Assuntos
Autorrenovação Celular , Expressão Gênica , Genes Reporter , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Transgenes , Animais , Biomarcadores , Diferenciação Celular/genética , Linhagem da Célula/genética , Separação Celular/métodos , Ensaio de Unidades Formadoras de Colônias , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Hematopoese , Imunofenotipagem , Camundongos , Camundongos Transgênicos , Proteínas Recombinantes de Fusão , Análise de Célula Única
11.
Food Nutr Bull ; 34(3 Suppl): S181-94, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24261076

RESUMO

BACKGROUND: Despite the existence of a strong evidence base for investing in infant and young child feeding (IYCF), sufficiently supported IYCF policies and programs are rare. OBJECTIVE: To develop evidence-based advocacy strategies in Bangladesh, Ethiopia, and Vietnam to enable policy change and to increase investments in and ensure scale-up and sustainability of IYCF programs. METHODS: Situational analysis, formative and opinion leader research, and stakeholder consultations were used to develop three contextualized advocacy strategies. RESULTS: Data were used to determine how IYCF was perceived and prioritized, identify opinion leaders and partners, identify barriers to and opportunities for strengthening commitment, and select messages, materials, and communication channels. Opinion leader research showed that malnutrition was a concern but not a priority for policy action. Where food security was an issue, poverty reduction strategies rather than IYCF programs were viewed as the solution. Few opinion leaders were aware of the importance of the first 1000 days of life. In addition to policy gaps, awareness and implementation of existing policies were limited. This was often complicated by intragovernment conflicts and perspectives. Advocacy messages needed to be evidence based and delivered by credible champions. Engaging medical associations and the media presented an opportunity rarely leveraged in IYCF advocacy. CONCLUSIONS. Although sociopolitical contexts may vary, awareness of the importance of IYCF is an overarching advocacy challenge. Consequently, investments in IYCF programs and policies lag. Evidence-based advocacy design has a potential for impact on national policies, investments, and commitment to implementation and should be used more widely to inform program design.


Assuntos
Serviços de Saúde da Criança/métodos , Medicina Baseada em Evidências/métodos , Promoção da Saúde/métodos , Fenômenos Fisiológicos da Nutrição do Lactente/legislação & jurisprudência , Política Nutricional/legislação & jurisprudência , Bangladesh , Aleitamento Materno , Serviços de Saúde da Criança/legislação & jurisprudência , Pré-Escolar , Países em Desenvolvimento , Etiópia , Medicina Baseada em Evidências/legislação & jurisprudência , Abastecimento de Alimentos , Promoção da Saúde/legislação & jurisprudência , Humanos , Lactente , Recém-Nascido , Estado Nutricional , Pobreza , Vietnã
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