Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
J Dent ; 144: 104937, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38479706

RESUMEN

OBJECTIVES: To investigate the influence of the 3D printed micro-structured surfaces on the bond strength of zirconia to resin cement. METHODS: Zirconia specimens were divided into five groups based on manufacturing technique and surface preparation: (1) milled zirconia (M group); (2) milled zirconia airborne abraded (MA group); (3) printed zirconia (M group); (4) printed zirconia airborne abraded (PA group); and (5) printed zirconia with micro-structured surface (PM group). The surface morphology, cross-sectional morphology, and elemental composition were observed using a scanning electron microscope (SEM). Surface roughness was measured using a laser scanning confocal microscope (SLCM). Shear bond strength (SBS) was measured using a universal testing machine after bonding resin cement (n = 10). The failure modes of the bonded fracture interfaces were observed and counted using a stereomicroscope and a SEM. In addition, boundary dimensional accuracy (n = 10) and micro-structural dimensional accuracy (n = 20) of printed zirconia specimens with micro-structured surfaces were measured using digital calipers and Fiji software. The crystalline phase changes before and after surface treatment were investigated using X-ray diffractometry. Data was analysed using one-way ANOVA and Tukey HSD post-hoc tests (α = 0.05). RESULT: The surface micro-structures of the PM group had regular morphology and no obvious defects. The surface roughness results showed that the PM group had higher Sa (42.21±1.38 um) and Ra (21.25±1.80 um) values than the other four groups (p < 0.001). The SBS test showed that the bond strength of the PM group reached 11.23 ± 0.66 MPa, which was 55.97% (p < 0.001) higher than that of the P group (7.20 ± 1.14 MPa). The boundary dimensional accuracy of the PM group was proficient (diameter: 99.63 ± 0.31%, thickness: 98.05 ± 1.12%), and the actual fabrication dimensions of the hexagonal micro-structures reached 77.45%-80.01% of the original design. The micro-structured surface did not affect the crystalline phase of zirconia. CONCLUSIONS: The current study illustrates that 3D-printed microstructured surfaces effectively improve the bond strength of zirconia to resin cements. CLINICAL SIGNIFICANCE: With the advantage of 3D printing, this study provides a new idea for improving the bonding properties of zirconia.


Asunto(s)
Recubrimiento Dental Adhesivo , Materiales Dentales , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Impresión Tridimensional , Cementos de Resina , Resistencia al Corte , Propiedades de Superficie , Circonio , Circonio/química , Cementos de Resina/química , Materiales Dentales/química , Humanos , Análisis del Estrés Dental , Microscopía Confocal , Diseño Asistido por Computadora , Estrés Mecánico
2.
J Prosthet Dent ; 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38061938

RESUMEN

STATEMENT OF PROBLEM: The use of intraoral scanners (IOSs) correlates with clinical outcome and patient satisfaction. While the accuracy of IOSs has been well evaluated, studies on the effect of scanning duration on data accuracy are limited. PURPOSE: The purpose of this in vitro study was to investigate the relationship between different scanning durations and the accuracy of the scanned data. MATERIAL AND METHODS: Two experienced operators used the same intraoral scanner (TRIOS 3; 3Shape A/S) to scan a gypsum cast, but with 5 different scanning durations (30 seconds, 60 seconds, 90 seconds, 120 seconds, and 180 seconds), and the trueness of the scanned data was assessed. Ten scans for each duration group were performed, and all the acquired data were evaluated for precision analysis. In addition, each scanned complete arch cast was divided into anterior and posterior regions at the canine teeth, and the 3-way ANOVA test was used to assess the scanning trueness and precision of the scanned anterior and posterior dental arch. RESULTS: The intraoral scanning results between the 2 operators were highly consistent. The data of the 30-second group showed the lowest trueness and precision (P<.001), whereas no significant difference was found among the other groups (P>.05). The trueness and precision of the scanning data in the posterior region was inferior to that in the anterior region (P<.001). CONCLUSIONS: The duration time of the intraoral scanning (ranging from 60 seconds to 180 seconds) did not influence the accuracy of the acquired data, while excessively rapid scanning adversely affected accuracy.

3.
Int J Mol Med ; 52(6)2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37830154

RESUMEN

Following the publication of the above article, an interested reader drew to the authors' attention that, in Fig. 2 on p. 1408, the microscopic images shown for the light scope images (upper row) and the green fluorescence images (lower row) appeared to be overlapping, such that these images appeared to have been derived from the same original sources even though they were intended to portray the results from differently performed experiments. After having re­examined their figures, the authors realized that this figure was assembled incorrectly. The revised version of Fig. 2, showing the correct data for all four experimental panels, is shown below. Note that the errors made during the assembly of these figures did not affect the overall conclusions reported in the paper. All the authors agree with the publication of this corrigendum, and are grateful to the Editor of International Journal of Molecular Medicine for allowing them the opportunity to publish this. They also apologize to the readership for any inconvenience caused. [International Journal of Molecular Medicine 37: 1405­1411, 2016; DOI: 10.3892/ijmm.2016.2539].

4.
Ann Palliat Med ; 10(10): 10414-10424, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34763487

RESUMEN

BACKGROUND: Since December 2019, there have been cases of infectious pneumonia of unknown cause in Wuhan, Hubei Province, China. On January 12, 2020, the World Health Organization (WHO) named it COVID-19. There are few studies on the clinical characteristics of patients with COVID-19, and results vary widely in sample sizes. METHODS: Chinese and English databases were searched with "Infectious pneumonia", "COVID-19", "CT", "SARS-COV-2", and "Diagnose" as keywords. Rev Man 5.3 software provided by the Cochrane system was used to assess the quality of the included literature. RESULTS: Of the 18 included studies, ground-glass shadow was the most common computed tomography (CT) sign [95% confidence interval (CI): 0.79-0.97], followed by thickening of the blood vessels (95% CI: 0.63-0.78), and pleural thickening (95% CI: 0.02-0.15). Of the 18 studies, 12 reported that the lesions were externally subpleural (95% CI: 0.132-0.173), and 6 reported that the lesions were distributed in a single lobe (95% CI: 0.598-0.841). The heterogeneity test results showed that the morphology of the lesions was cord-like (95% CI: 0.092-0.172), grid-like (95% CI: 0.152-0.193), patchy (95% CI: 0.192-0.313), and nodular (95% CI: 0.591-0.745). DISCUSSION: Ground-glass opacity was a typical CT manifestation for patients with infectious pneumonia, and CT signs were instrumental in diagnosing this disease.


Asunto(s)
COVID-19 , Humanos , Estudios Retrospectivos , SARS-CoV-2 , Tomografía Computarizada por Rayos X , Organización Mundial de la Salud
5.
Polymers (Basel) ; 13(20)2021 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-34685268

RESUMEN

Three-dimensional printing polyetheretherketone (PEEK) provides a new choice for dental prostheses, while its appropriate bonding procedure and adhesive performance are still unclear. This study aimed to investigate the adhesive performance of printed polyetheretherketone (PEEK) after acid etching to veneering resin. In total, 182 PEEK specimens (including 91 printed and 91 milled specimens) were distributed to 14 subgroups (n = 13/subgroup), according to the manufacturing process and surface treatment. The specimens were polished and etched with sulfuric acid for 0, 5, 30, 60, 90, 120, and 300 s, respectively. Two specimens in each subgroup were observed under a scanning electron microscope (SEM) for surface and cross-section morphology separately. Then, the specimens were treated with a bonding primer, and one specimen in each subgroup was prepared for cross-sectional observation under SEM. The residual 10 specimens of each subgroup bonded with veneering resin were tested with the shear bond strength tests (SBS) and failure modes analysis. Statistical analysis was performed by one-way ANOVA followed by the SNK-q post hoc test (p < 0.05). The etched pores on the PEEK surface were broadened and deepened under SEM over time. Printed PEEK etched for 30 s obtained the best SBS-to-veneering-resin ratio (27.90 ± 3.48 MPa) among the printed subgroups (p < 0.05) and had no statistical differences compared with milled PEEK etched for 30 s. The SBS of the milled subgroups etched from 5 to 120 s were over 29 MPa without significant between-group statistical differences. Hence, printed PEEK can be coarsened effectively by 30 s of sulfuric acid etching. The adhesion efficacy of printed PEEK to veneering resin was qualified for clinical requirements of polymer-based fixed dentures.

6.
Front Pediatr ; 9: 671536, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34485189

RESUMEN

Glycogen storage disease (GSD) Ib is a rare genetic metabolic disorder caused by gene mutation in the glucose 6-phosphate transport gene SLC37A4 (OMIM# 602671). This study aimed to explore the association between a novel lipoprotein lipase (LPL) mutation and severe hypertriglyceridemia in a GSD Ib infant with severe hypertriglyceridemia. A 5-month-old girl was admitted to our hospital because of repeated episodes of low-grade fever over the past month and because of neutropenia. The patient was diagnosed with GSD Ib and severe hypertriglyceridemia based on clinical manifestations and laboratory test results. Next-generation sequencing and Sanger sequencing were then applied to DNA from the peripheral blood of the patient and her parents to analyze gene mutations. Pathogenicity prediction analysis was performed using Sorting Intolerant From Tolerant (SIFT) and PolyPhen-2 platforms. The results revealed that this infant carried a compound heterozygous variation in the SLC37A4 gene, a c.1043T > C (p.L348P) mutation derived from her mother and a c.572C > T (p.P191L) mutation derived from her father. In addition, a novel c.483delA (p. A162Pfs*10) frameshift mutation was found in the patient's LPL gene exon 4, which was derived from the heterozygous carrier of her father. The SIFT and PolyPhen-2 prediction programs indicated that these mutations were likely harmful. Medium-chain triglyceride milk and granulocyte colony-stimulating factor subcutaneous injection alleviated the symptoms. Our findings identified a novel LPL gene frameshift mutation combined with SLC37A4 gene compound heterozygous mutations in a GSD Ib infant with severe hypertriglyceridemia.

7.
BMC Oral Health ; 20(1): 7, 2020 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-31907038

RESUMEN

BACKGROUND: Appropriate mechanical stimulation is essential for bone homeostasis in healthy periodontal tissues. While the osteogenesis and osteoclast differentiation of inflammatory periodontal ligament cells under different dynamic loading has not been yet clear. The aim of this study is to clarify the inflammatory, osteogenic and pro-osteoclastic effects of different cyclic stress loading on the inflammatory human periodontal ligament cells (hPDLCs). METHODS: hPDLCs were isolated from healthy premolars and cultured in alpha minimum Eagle's medium (α-MEM). Lipopolysaccharides (LPS) were used to induce the inflammation state of hPDLCs in vitro. Determination of LPS concentration for the model of inflammatory periodontium was based on MTT and genes expression analysis. Then the cyclic stress of 0, 0-50, 0-90 and 0-150 kPa was applied to the inflammatory hPDLCs for 5 days respectively. mRNA and protein levels of osteogenic, osteoclastic and inflammation-related markers were examined after the treatment. RESULTS: MTT and RT-PCR results showed that 10 µg/ml LPS up-regulated TNF-α, IL-1ß, IL-6, IL-8 and MCP-1 mRNA levels (P < 0.05) and did not affect the cell viability (P > 0.05). The excessive loading of stress (150 kPa) with or without LPS strongly increased the expression of inflammatory-related markers TNF-α, IL-1ß, IL-6, IL-8, MCP-1 (P < 0.05) and osteoclastic markers RANKL, M-CSF, PTHLH and CTSK compared with other groups (P < 0.05), but had no significant effect on osteogenic genes. While 0-90 kPa cyclic pressure could up-regulate the expression of osteogenic genes ALP, COL-1, RUNX2, OCN, OPN and OSX in the healthy hPDLSCs. CONCLUSIONS: Collectively, it could be concluded that 0-150 kPa was an excessive stress loading which accelerated both inflammatory and osteoclastic effects, while 0-90 kPa may be a positive factor for the osteogenic differentiation of hPDLCs in vitro.


Asunto(s)
Lipopolisacáridos/farmacología , Osteoclastos/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Ligamento Periodontal/efectos de los fármacos , Diferenciación Celular , Células Cultivadas , Humanos
8.
Medicine (Baltimore) ; 98(46): e17954, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31725654

RESUMEN

BACKGROUND: Published studies have investigated the prognostic roles of estrogen receptor alpha (ERα) and estrogen receptor beta (ERß) in gastroesophageal cancer patients with the controversial results. The aim of the study was to systematically evaluate the impacts of ERα and ERß on the overall survival (OS) in patients. METHOD: Relevant eligible studies were extracted from PubMed, Embase, Web of Science, CNKI and Wanfang databases (from the start date to November 2018) following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. HR (hazard ratio) with 95% confidence intervals (CIs) were used to assess the prognostic values of ERα and ERß for OS in patients. RESULTS: High ERα expression was associated with poor OS (HR = 1.58, 95% CI = 1.29-1.94, P < .001) and ERß with better OS (HR = 0.56, 95% CI = 0.37-0.83, P = .004) in gastroesophageal cancer. Furthermore, unfavorable OS was found in Chinese gastroesophageal patients with higher ERα expression (HR = 1.57, 95% CI = 1.25-1.96, P < .001) and better OS with higher ERß expression (HR = 0.51, 95% CI = 0.31-0.83, P < .01) in our subgroup analysis. Meanwhile, worse OS was found in esophageal squamous cell carcinoma (ESCC) patients with high ERα expression (HR = 1.74, 95% CI = 1.33-2.26, P < .001), and favorable OS in ESCC with ERß overexpression (HR = 0.40, 95% CI = 0.31-0.52, P < .001). Besides, high ERα expression was associated with lower tumor differentiation in ESCC (OR = 1.64; 95% CI = 1.02-2.64, P = .04) and ERß was linked with better tumor differentiation in gastric adenocarcinoma (GCA) (OR = 0.49; 95% CI = 0.26-0.94, P = .03). CONCLUSIONS: ERα and ERß might serve as potential prognostic biomarkers for gastroesophageal cancer patients. ERα overexpression predicted poor OS and lower tumor differentiation, and ERß suggested favorable OS and better tumor differentiation. Further related studies should be performed to test these results.


Asunto(s)
Neoplasias Esofágicas/mortalidad , Receptor alfa de Estrógeno/biosíntesis , Receptor beta de Estrógeno/biosíntesis , Neoplasias Gástricas/mortalidad , Biomarcadores de Tumor , China/epidemiología , Neoplasias Esofágicas/sangre , Neoplasias Esofágicas/patología , Receptor alfa de Estrógeno/sangre , Receptor beta de Estrógeno/sangre , Humanos , Pronóstico , Modelos de Riesgos Proporcionales , Neoplasias Gástricas/sangre , Neoplasias Gástricas/patología , Análisis de Supervivencia
9.
Oncol Lett ; 15(6): 10070-10076, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29928376

RESUMEN

Multidrug resistance (MDR) in leukemia cells is a major obstacle to chemotherapeutic treatment. High expression and constitutive activation of multidrug resistance protein 1 (MRP1) has been associated with the development of resistance to anticancer drugs in a number of tumor types. The activity of c-Jun N-terminal kinase 1 (JNK1) is associated with the occurrence of MDR and MRP1 expression. The present study aimed to investigate the ability of solanine to resensitize the Adriamycin® (ADR)-resistant human myelogenous leukemia cell line K562/ADM to ADR. Results of the Cell Counting Kit-8 assay demonstrated that solanine inhibited K562/ADM cell proliferation. K562/ADM cell sensitivity to ADR was increased following treatment with solanine, indicated by increased intracellular accumulation of ADR. Western blotting demonstrated that treatment with solanine led to reduced MRP1 protein expression, suggesting that solanine-induced ADR accumulation is due to the downregulation of MRP1 expression. Solanine-mediated MRP1 downregulation was observed to be dependent on the JNK signaling pathway. In conclusion, the results of the present study suggest that solanine reverses MDR in K562/ADM cells and may represent a novel therapeutic agent for the treatment of human myelogenous leukemia.

10.
Oncol Lett ; 15(5): 7383-7388, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29731890

RESUMEN

Solanine is an alkaloid and is the main extract of the traditional Chinese herb, Solanum nigrum Linn. It has been reported that Solanine has anti-inflammatory and antitumor properties. The present study aimed to investigate the antitumor effect of Solanine in Jurkat cells and demonstrate the molecular mechanism of antitumor activity of Solanine. A Cell Counting Kit-8 assay demonstrated that Solanine inhibited the proliferation of Jurkat cells in a dose-and time-dependent manner. Cell apoptosis was measured by flow cytometry. Flow cytometry revealed that Solanine induced apoptosis in a dose-dependent manner in Jurkat cells. Reverse transcription-quantitative polymerase chain reaction demonstrated that Solanine modulated the mRNA levels of B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein (Bax). Additionally, Bcl-2 and Bax expression was measured using western blot analysis. Western blot analysis revealed a significant increase in the expression of Bax and decrease in the expression of Bcl-2. Solanine increased the chemosensitivity of Jurkat cells to Adriamycin. In summary, the present results indicated that the antitumor activity of Solanine was associated with inhibition of cell proliferation, induction of apoptosis and increasing cytotoxicity of Adriamycin. Therefore, Solanine may have potential as a novel agent for the treatment of acute lymphocytic leukemia.

11.
Oncol Rep ; 37(5): 2735-2742, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28358418

RESUMEN

Chemotherapy is the main treatment method for patients with chronic myeloid leukemia (CML) and has achieved marked results. However, the acquisition of multidrug resistance (MDR) has seriously affected the quality of life and survival rate of patients. The overexpression of the inhibitors of apoptosis proteins (IAPs) and the adenosine triphosphate (ATP)-dependent binding cassette (ABC) transporters are the two main causes of MDR. Apollon and MDR1 are the most important and representative members, respectively, among the IAPs and ABC transporters. In the present study, we investigated the role of Apollon and MDR1 in chemotherapy resistance and their mechanism of interaction. We respectively knocked down the expression of Apollon and MDR1 using short hairpin RNA (shRNA) in adriamycin (ADM) resistant human CML K562 cells and examined the drug sensitivity, the consequences with regard to ADM accumulation and the alterations in the expression of Apollon and MDR1. The expression levels of Apollon and MDR1 mRNA were higher in the K562/ADM cells compared with the parental K562 cells as determined by reverse transcription­polymerase chain reaction (RT-PCR). The plasmids of Apollon and MDR1 shRNA were respectively stably transfected into K562/ADM cells using Lipofectamine 2000. The transfection efficiency was detected by fluorescence microscopy. Cell Counting Kit-8 (CCK-8) assay revealed that Apollon or MDR1 knockdown significantly increased the chemosensitivity of the K562/ADM cells to ADM. Flow cytometric assay revealed that K562/ADM/shMDR1 cells exhibited a significantly increased intracellular accumulation of ADM, and that changes were not found in the K562/ADM/shApollon cells. Compared with the parental K562/ADM cells, a significantly decreased expression of Apollon mRNA and protein was determined in the K562/ADM/shApollon cells without affecting the expression of MDR1 as determined by RT-PCR and western blotting. Likewise, the expression levels of MDR1 mRNA and protein also markedly downregulated in the K562/ADM/shMDR1 cells had no effect on Apollon expression. Collectively, our findings demonstrated, for the first time, that downregulation of Apollon or MDR1 through stable transfection with the Apollon- or MDR1-targeting shRNA induced MDR reversal through respective inhibition of Apollon or MDR1 expression and function. However, the reversal mechanism of Apollon and MDR1 revealed no direct interaction with each other.


Asunto(s)
Resistencia a Antineoplásicos/genética , Proteínas Inhibidoras de la Apoptosis/genética , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Doxorrubicina/farmacocinética , Doxorrubicina/farmacología , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Múltiples Medicamentos/genética , Resistencia a Antineoplásicos/efectos de los fármacos , Regulación Leucémica de la Expresión Génica/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Terapia Genética/métodos , Humanos , Células K562 , ARN Interferente Pequeño
12.
Int J Oncol ; 49(6): 2529-2537, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27779650

RESUMEN

Multidrug resistance (MDR) plays a pivotal role in human chronic myelogenous leukemia (CML) chemotherapy failure. MDR is mainly associated with the overexpression of drug efflux transporters of the ATP-binding cassette (ABC) proteins. Phosphoinositide 3-kinase (PI3K)/Akt signaling cascade is involved in the MDR phenotype and is correlated with multidrug resistance 1 (MDR1)/P-glycoprotein (P-gp), multidrug resistance-associated protein 1 (MRP1) and breast cancer resistance protein (BCRP) expression in many human malignancies. Homeobox (HOX) B4, a member of the HOX gene family, has been reported to be correlated with occurrence, development, poor prognosis and drug resistance of human leukemia. In the present study, HOXB4 expression was analyzed in K562 cell line and its MDR subline K562/ADM. Compared with K562 cells, drug-resistant K562/ADM cells demonstrated evidently higher HOXB4 expression. In addition, we firstly investigated the reversal effect of HOXB4 deletion on K562/ADM cells and the underlying mechanism. The Cell Counting kit-8 (CCK-8) and flow cytometry assays showed that knockdown of HOXB4 enhanced chemosensitivity and decreased drug efflux in K562/ADM cells. Moreover, HOXB4 knockout led to downregulation of P-gp, MRP1 and BCRP expression and PI3K/Akt signaling activity, suggesting that repression of HOXB4 might be a key point to reverse MDR of K562/ADM cells.


Asunto(s)
Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Resistencia a Múltiples Medicamentos/genética , Resistencia a Antineoplásicos/genética , Proteínas de Homeodominio/genética , Leucemia Mieloide/tratamiento farmacológico , Factores de Transcripción/genética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/biosíntesis , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/biosíntesis , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/genética , Transporte Biológico/efectos de los fármacos , Línea Celular Tumoral , Citarabina/farmacología , Doxorrubicina/farmacología , Etopósido/farmacología , Humanos , Leucemia Mieloide/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/biosíntesis , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Interferencia de ARN , ARN Interferente Pequeño/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Vindesina/farmacología
13.
Int J Mol Med ; 37(5): 1405-11, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27035504

RESUMEN

Multidrug resistance (MDR) of leukemia cells is a major obstacle in chemotherapeutic treatment. The high expression and constitutive activation of P-glycoprotein (P-gp) and multidrug resistance protein-1 (MRP-1) have been reported to play a vital role in enhancing cell resistance to anticancer drugs in many tumors. The present study aimed to investigate the reversal of MDR by silencing homeobox A10 (HOXA10) in adriamycin (ADR)-resistant human chronic myelogenous leukemia (CML) K562/ADM cells by modulating the expression of P-gp and MRP-1. K562/ADM cells were stably transfected with HOXA10-targeted short hairpin RNA (shRNA). The results of reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis showed that the mRNA and protein expression of HOXA10 was markedly suppressed following transfection with a shRNA-containing vector. The sensitivity of the K562/ADM cells to ADR was enhanced by the silencing of HOXA10, due to the increased intracellular accumulation of ADR. The accumulation of ADR induced by the silencing of HOXA10 may be due to the downregulation of P-gp and MRP-1. Western blot analysis revealed that downregulating HOXA10 inhibited the protein expression of P-gp and MRP-1. Taken together, these results suggest that knockdown of HOXA10 combats resistance and that HOXA10 is a potential target for resistant human CML.


Asunto(s)
Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Resistencia a Múltiples Medicamentos , Resistencia a Antineoplásicos/genética , Regulación Leucémica de la Expresión Génica , Proteínas de Homeodominio/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Línea Celular Tumoral , Técnicas de Silenciamiento del Gen , Proteínas Homeobox A10 , Humanos , Células K562 , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/genética
14.
Int J Oncol ; 48(5): 2063-70, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26984633

RESUMEN

One of the major causes of failure in chemotherapy for patients with human chronic myelogenous leukemia (CML) is the acquisition of multidrug resistance (MDR). MDR is often associated with the overexpression of drug efflux transporters of the ATP-binding cassette (ABC) protein family. Timosaponin A-III (TAIII), a saponin isolated from the rhizome of Anemarrhena asphodeloides, has previously demonstrated the ability to suppress certain human tumor processes and the potential to be developed as an anticancer agent. Nevertheless, the ability of TAIII to reverse MDR has not yet been explored. In this study, the adriamycin (ADM) resistance reversal effect of TAIII in human CML K562/ADM cells and the underlying mechanism was investigated. The Cell Counting Kit-8 (CCK-8) assay showed that TAIII had a reversal effect on the drug resistance of K562/ADM cells. Flow cytometry assay showed increased intracellular accumulation of ADM after cells were pretreated with TAIII, and the changes in the accumulation of rhodamine-123 (Rho-123) and 5(6)-carboxyfluorescein diacetate (CFDA) dye in K562/ADM cells were determined to be similar to the changes of intracellular accumulation of ADM. After pretreatment of cells with TAIII, the decreasing expression of P-gp and MRP1 mRNA was examined by reverse transcription polymerase chain reaction (RT-PCR). Western blotting showed TAIII inhibiting P-gp and MRP1 expression depended on the PI3K/Akt signaling pathway by decreasing the activity of p-Akt. Moreover, wortmannin an inhibitor of PI3K/Akt signaling pathway has a strong inhibitory effect on the expression of p-Akt, P-gp and MRP1. Besides, the combined treatment with TAIII did not have an affect on wortmannin downregulation of p-Akt, P-gp and MRP1. Taken together, our findings demonstrate, for the first time, that TAIII induced MDR reversal through inhibition of P-gp and MRP1 expression and function with regained adriamycin sensitivity which might mainly correlate to the regulation of PI3K/Akt signaling pathway.


Asunto(s)
Antineoplásicos/farmacología , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Saponinas/farmacología , Esteroides/farmacología , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Regulación hacia Abajo , Doxorrubicina/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Células K562 , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...