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1.
Ann Hematol ; 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38494551

RESUMEN

Myelofibrosis (MF) is a myeloproliferative neoplasm (MPN) with a poor prognosis, and allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the only treatment with curative potential. Ruxolitinib, a JAK1/2 inhibitor, has shown promising results in improving patients' symptoms, overall survival, and quality of life, and can be used as a bridging therapy to HSCT that increases the proportion of transplantable patients. However, the effect of this and similar drugs on HSCT outcomes is unknown, and the reports on their efficacy and safety in the peri-transplantation period vary widely in the published literature. This paper reviews clinical data related to the use of JAK inhibitors in the peri-implantation phase of hematopoietic stem cell transplantation for primary myelofibrosis and discusses their efficacy and safety.

2.
Infect Drug Resist ; 16: 1099-1106, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36861016

RESUMEN

Objective: A strain of Proteus penneri with carbapenem resistance was found in a patient with a diabetic foot infection. We studied drug resistance, genome, and homology of P. penneri to support clinical prevention and treatment of infection caused by carbapenem-resistant P. penneri (CR-PPE). Methods: The strains were obtained through bacterial culture from purulence. VITEK 2 compact (GN13) and Kirby-Bauer (K-B) disk diffusion methods were used for antimicrobial susceptibility testing. Ceftriaxone, amikacin, gentamicin, ampicillin, aztreonam, ceftazidime, ciprofloxacin, levofloxacin, cefepime, trimethoprim-sulfamethoxazole, tobramycin, cefotetan, piperacillin-tazobactam, ampicillin-sulbactam, ertapenem, piperacillin, meropenem, cefuroxime, cefazolin, cefoperazone/sulbactam, cefoxitin, and imipenem were used for antimicrobial susceptibility testing. After bacterial genome extraction, sequencing, and sequence assembly, whole-genome sequencing (WGS) was performed to explore the CR-PPE genotype. Results: CR-PPE was resistant to two carbapenems (imipenem and ertapenem), ceftriaxone, and cefazolin, and was sensitive to aztreonam, piperacillin-tazobactam, and cefotetan. WGS results depict that the resistant phenotype of CR-PPE is consistent with the genotype, without common virulence genes of Enterobacteriaceae bacteria detected (virulence factor database). The carbapenem resistance gene blaNMD-1 is contained in a new plasmid, pWF127-NDM. The transposon Tn125 in pWF127-NDM carrying blaNMD-1 has almost the same structure as Tn125 in the reference plasmid pHFK418-NDM (Accession: MH491967). In addition, through phylogenetic analysis, CR-PPE depicts the closest evolutionary relationship with GCF 024129515.1, which was found in Gallus gallus in the Czech Republic in 2019 (downloaded from National Center for Biotechnology Information database). According to the evolutionary tree, CR-PPE has high homology with the two P. penneri strains found in China. Conclusion: CR-PPE exhibits strong drug resistance owing to the presence of multiple resistance genes. CR-PPE infection should receive more attention, especially in patients with underlying diseases, such as diabetes and weak immunity.

3.
J Colloid Interface Sci ; 629(Pt A): 554-562, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36088700

RESUMEN

Magnetothermal therapy (MHT) has attracted significant attention due to the advantages of non-/minimal invasiveness, high efficiency, and excellent tissue penetration. However, developing small MHT agents (<50 nm) with excellent magnetothermal conversion performance and high tumor enrichment is a great challenge. Herein, a macrophage-mediated delivery of small Fe@Fe3O4-DHCA nanoparticles (∼14 nm) was designed for enhanced magnetic resonance imaging (MRI) and MHT of solid tumors. Based on the "Trojan horse" loading properties of the macrophages (RAW267.4 cells), the aggregation of Fe@Fe3O4-DHCA nanoparticles in the cells results in an enhanced MRI and magnetothermal performance in vitro. In addition, the MHT effect of RAW267.4 loaded with Fe@Fe3O4-DHCA in vivo is better than that of Fe@Fe3O4-DHCA alone, due to the tumor-targeting performance of RAW267.4 cells. This macrophage-mediated delivery provides a new strategy for the enhanced treatment effect of MHT based on Fe@Fe3O4-DHCA nanoparticles, and has great application potential for clinic tumor therapy.


Asunto(s)
Nanopartículas de Magnetita , Nanopartículas , Línea Celular Tumoral , Magnetismo , Imagen por Resonancia Magnética/métodos , Macrófagos
4.
Front Plant Sci ; 13: 984233, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36061791

RESUMEN

The WRKY transcription factors (TFs) are among the most diverse TF families of plants. They are implicated in various processes related to plant growth and stress response. Kenaf (Hibiscus cannabinus L.), an important fiber crop, has many applications, including the phytoremediation of saline-alkaline soil. However, the roles of WRKY TFs in kenaf are rarely studied. In the present study, 46 kenaf WRKY genes were genome-widely identified and characterized by gene structure, phylogeny and expression pattern analysis. Furthermore, the HcWRKY44 gene was functionally characterized in Arabidopsis under salinity and drought stresses. HcWRKY44 is a nuclear-localized protein that is positively induced by salinity and drought, with roots showing maximum accumulation of its transcripts. Under NaCl and abscisic acid (ABA) stress conditions, plants overexpressing HcWRKY44 had higher germination rates, better root growth and increased survival than control plants; however, it did not improve the ability to withstand drought stress. Moreover, ABA signaling genes (ABI1, ABI2, and ABI5), ABA-responsive genes (ABF4, RD29B, COR15A, COR47, and RD22), stress-related genes (STZ, P5CS, and KIN1), and ionic homeostasis-related genes (SOS1, AHA1, AHA2, and HKT1) were positively induced in HcWRKY44 transgenic plants under NaCl treatment. These results suggest that HcWRKY44 improved plant's tolerance to salt stress but not osmotic stress through an ABA-mediated pathway. In summary, this study provides provided comprehensive information about HcWRKY genes and revealed that HcWRKY44 is involved in salinity tolerance and ABA signaling.

5.
J Healthc Eng ; 2022: 4012304, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35132357

RESUMEN

OBJECTIVE: To explore the application value of perioperative nursing for patients with brain tumors with epilepsy symptoms under the cortical electrocorticography (EEG) monitoring. METHODS: A total of 86 patients with brain tumor complicated with epilepsy admitted to the department of brain surgery of our hospital from January 2018 to December 2019 were selected as the research objects, and all underwent resection under cortical EEG monitoring. According to different nursing methods, they were divided into the control group and observation group, each with 43 cases. The control group was given perioperative basic nursing, and the observation group was given perioperative comprehensive nursing. The EEG image of the patient during the operation was observed by a portable EEG monitor. Anxiety and depression were assessed by self-rating anxiety scale (SAS) and self-rating depression scale (SDS) scores. The self-made satisfaction questionnaire was used to investigate the nursing satisfaction. A visual analogue (VAS) score is used to assess pain degree. A multiparameter monitor was used to detect the patient's heart rate (HR), systolic blood pressure (SBP), and diastolic blood pressure (DBP). The quality of life was assessed by the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-30). The complication rate and recurrence rate were also counted. RESULTS: Eighty-six patients with epileptic brain tumor developed spikes in 35 cases, including 7 meningiomas, 22 gliomas, and 6 cholesteatomas; 27 cases of sharp waves, including 14 meningiomas, 12 gliomas, and 1 case of cholesteatomas; and 24 cases of complex wave, including 9 cases of meningioma, 13 cases of glioma, and 2 cases of cholesteatoma. There was no significant difference in the scores of SAS, SDS, VAS, HR, SBP, DBP, and quality of life between the two groups at T0. The VAS score increased at T1 and T2, and the increase in the control group was greater than that in the observation group. At T3 and T4, the SAS, SDS, and VAS scores of the two groups decreased, and the observation group decreased more than the control group. HR, SBP, and DBP of the two groups showed an upward trend at T1 and T2, and the increase in the control group was more significant than that in the observation group. At T3, the three indicators of the two groups decreased, and the observation group decreased more significantly than the control group. At T4, the scores of all indicators of the quality of life of the two groups increased, and the observation group increased more significantly than the control group. The nursing satisfaction of the observation group was higher than that of the control group. The complication rate and recurrence rate in the observation group were decreased compared with the control group. CONCLUSION: Perioperative comprehensive nursing intervention for patients with epileptic brain tumor undergoing resection under cortical EEG monitoring can reduce or even eliminate the recurrence rate of epilepsy, reduce the patient's pain and stress response, and improve the patient's quality of life. It can also reduce the occurrence of complications, improve nursing satisfaction, thereby improving patient compliance, and has a high clinical application value.


Asunto(s)
Neoplasias Encefálicas , Colesteatoma , Epilepsia , Glioma , Neoplasias Meníngeas , Meningioma , Encéfalo , Neoplasias Encefálicas/complicaciones , Neoplasias Encefálicas/cirugía , Electrocorticografía , Epilepsia/cirugía , Glioma/complicaciones , Glioma/cirugía , Humanos , Dolor , Enfermería Perioperatoria , Calidad de Vida
6.
J Trace Elem Med Biol ; 71: 126927, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35030482

RESUMEN

BACKGROUND: It is a consensus that selenomethionine (SeMet) can protect liver from damage, but the immune mechanism of SeMet in acute liver injury (ALI) is still unclear. This study aims to investigate the protective effects of SeMet against ALI and to elucidate the possible immune mechanism. METHODS: Firstly, the role of SeMet in CCl4-induced ALI mice was investigated through survival rate, serum ALT and AST, liver necrosis and apoptosis analysis. The expression and secretion of inflammatory cytokines and chemokines in the liver and serum of CCl4-induced ALI mice were analyzed by qRT-PCR and ELISA. Then the immune cell phenotypes were analyzed by flow cytometry and confocal imaging. In addition, MDSCs depletion, CXCL12/CXCR4 axis blocking and selenoprotein S (SELENOS) knockdown assays were used to reveal the immune mechanism of SeMet. RESULTS: We found that SeMet prolonged survival rate, decreased the serum ALT and AST, alleviated liver necrosis and inhibited hepatocytes apoptosis. Prospective, SeMet decreased the expression of IL-6 and TNF-α, and increased the expression of IL-10. Interestingly, SeMet decreased the expression of MCP-1, while increased the expression of CXCL12. The immune analysis showed that SeMet decreased the activation of T cells through promoting MDSCs accumulation mediated by CXCL12/CXCR4 axis. Furthermore, SeMet increased SELENOS expression in vivo, and knockdown of SELENOS effectively abolished the protective effect of SeMet during ALI. CONCLUSION: This study demonstrates that SeMet alleviates CCl4-induced ALI by promoting MDSCs accumulation through SELENOS mediated CXCL12/CXCR4 axis. Therefore, our study infers that selenium intake may be as a new therapeutic option for management of inflammation-mediated liver injury.


Asunto(s)
Selenio , Animales , Ratones , Selenio/análisis , Citocinas/metabolismo , Modelos Animales de Enfermedad , Estudios Prospectivos , Hígado/metabolismo , Selenometionina/farmacología , Suplementos Dietéticos , Selenoproteínas/metabolismo , Necrosis/metabolismo
8.
Brief Bioinform ; 22(3)2021 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-32987405

RESUMEN

Histone lysine demethylases (KDMs) play a vital role in regulating chromatin dynamics and transcription. KDM proteins are given modular activities by its sequence motifs with obvious roles division, which endow the complex and diverse functions. In our review, according to functional features, we classify sequence motifs into four classes: catalytic motifs, targeting motifs, regulatory motifs and potential motifs. JmjC, as the main catalytic motif, combines to Fe2+ and α-ketoglutarate by residues H-D/E-H and S-N-N/Y-K-N/Y-T/S. Targeting motifs make catalytic motifs recognize specific methylated lysines, such as PHD that helps KDM5 to demethylate H3K4me3. Regulatory motifs consist of a functional network. For example, NLS, Ser-rich, TPR and JmjN motifs regulate the nuclear localization. And interactions through the CW-type-C4H2C2-SWIRM are necessary to the demethylase activity of KDM1B. Additionally, many conservative domains that have potential functions but no deep exploration are reviewed for the first time. These conservative domains are usually amino acid-rich regions, which have great research value. The arrangements of four types of sequence motifs generate that KDM proteins diversify toward modular activities and biological functions. Finally, we draw a blueprint of functional mechanisms to discuss the modular activity of KDMs.


Asunto(s)
Secuencias de Aminoácidos , Histona Demetilasas/metabolismo , Catálisis , Dominio Catalítico , Núcleo Celular/enzimología , Cromatina/metabolismo , Histona Demetilasas/química , Humanos , Metilación , Unión Proteica , Especificidad por Sustrato
9.
Cell Mol Life Sci ; 78(1): 129-141, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32642789

RESUMEN

AlkB homologs (ALKBH) are a family of specific demethylases that depend on Fe2+ and α-ketoglutarate to catalyze demethylation on different substrates, including ssDNA, dsDNA, mRNA, tRNA, and proteins. Previous studies have made great progress in determining the sequence, structure, and molecular mechanism of the ALKBH family. Here, we first review the multi-substrate selectivity of the ALKBH demethylase family from the perspective of sequence and structural evolution. The construction of the phylogenetic tree and the comparison of key loops and non-homologous domains indicate that the paralogs with close evolutionary relationship have similar domain compositions. The structures show that the lack and variations of four key loops change the shape of clefts to cause the differences in substrate affinity, and non-homologous domains may be related to the compatibility of multiple substrates. We anticipate that the new insights into selectivity determinants of the ALKBH family are useful for understanding the demethylation mechanisms.


Asunto(s)
Enzimas AlkB/metabolismo , Enzimas AlkB/química , Enzimas AlkB/clasificación , Animales , ADN/metabolismo , Reparación del ADN , Humanos , Filogenia , Dominios Proteicos , ARN Mensajero/metabolismo , ARN de Transferencia/metabolismo , Especificidad por Sustrato
10.
J Physiol Anthropol ; 38(1): 7, 2019 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-31234934

RESUMEN

AIMS: To study the associations between fat distribution and lung functions in healthy subjects of young adults and to explore potential gender difference in these correlations. METHODS: A total of 2101 adult participants were recruited. Height, weight, and vital capacity index (VCI) were measured and recorded according to the national physical fitness test standard. Body compositions, including body mass index (BMI), body fat percentage (BFP), waist-to-hip ratio (WHR), fat-free mass (FFM), trunk muscle mass (TMM), fat mass (FM), visceral fat area (VFA), visceral adipose tissue (VAT), and subcutaneous adipose tissue (SAT), were conducted using body composition analyzer. Data were analyzed by SPSS 20.0 software. RESULTS: We found that male participants showed significantly higher BMI, WHR, FFM, TMM, VFA, and VCI, but lower FM, BFP, and SAT in comparison with women. However, there was no significant difference in VAT between the male and female. Lung functions represented by VCI were negatively correlated with FM, VAT, SAT, and VFA for both men and women (r < 0; P < 0.05). Among these negative correlations, VCI was more inversely correlated with VFA for men but with SAT for women, respectively. After dividing the whole populations by BMI, BFP, and WHR, further correlation analysis showed VCI was still more negatively correlated with VFA for all male subgroups (r < 0; P < 0.05). On the contrary, VCI was more negatively correlated with SAT in BMI-underweight, BMI-normal, BFP-low fat, BFP-normal fat, WHR-normal, and WHR-obese subgroups (r < 0; P < 0.05), while VFA and VAT was more inversely correlated with VCI in BMI- and BFP-overweight+obese subgroups (r < 0; P < 0.05). CONCLUSIONS: Fat accumulation is highly associated with the vital capacity index in young adults. In general, VCI was more negatively correlated with VFA for men but with SAT for women, respectively, in comparison with other tested indices.


Asunto(s)
Grasa Abdominal/fisiología , Composición Corporal/fisiología , Capacidad Vital/fisiología , Adolescente , Adulto , China/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Adulto Joven
11.
Int Immunopharmacol ; 74: 105708, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31254956

RESUMEN

BACKGROUND AND AIMS: Soluble E-cadherin (sE-cadherin) has been observed elevated in patients with various diseases, and implicated in the occurrence and development of those diseases. The implications of sE-cadherin in chronic hepatitis C virus (HCV) infection are still unclear. The purpose of this study is to explore the significance of sE-cadherin in chronic hepatitis C infection and the correlation with treatment response. METHODS: 87 chronic HCV infected patients and 60 healthy subjects were enrolled in this study. Blood samples from patients receiving the combined treatment of pegylated interferon-a (Peg-IFN-α) with ribavirin (RBV) were collected before treatment, during 4th, 12th therapy weeks, end of the treatment, and 24 weeks post-therapy. Plasma sE-cadherin level was detected by enzyme-linked immunosorbent assay (ELISA) and the relationship between sE-cadherin and antiviral treatment outcome was analyzed. RESULTS: Plasma sE-cadherin concentrations of Chronic HCV infected patients were significantly higher than that of healthy controls. A strong correlation between sE-cadherin level and the HCV viral load, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and also glutamyl transpeptidase (GGT) level was detected. Chronic HCV infected patients achieving rapid virological response (RVR) and sustained virological response (SVR) had lower baseline sE-cadherin concentrations compared with the non-RVR and non-SVR groups respectively. Univariate and multivariate regression analyses suggested that baseline plasma sE-cadherin level was predictive of therapeutic effect in patients with chronic HCV infection. CONCLUSION: Baseline sE-cadherin level could be considered as an independent predictor of SVR with Peg-IFN-α plus ribavirin therapy in the Chinese Han population chronic HCV infection patients. Effective antiviral therapy might restore sE-cadherin at physiological levels.


Asunto(s)
Biomarcadores Farmacológicos/sangre , Cadherinas/sangre , Hepacivirus/fisiología , Hepatitis C Crónica/diagnóstico , Inmunoterapia/métodos , Adulto , Antivirales/uso terapéutico , China , Quimioterapia Combinada , Femenino , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Interferón-alfa/uso terapéutico , Masculino , Persona de Mediana Edad , Polietilenglicoles/uso terapéutico , Pronóstico , Ribavirina/uso terapéutico , Carga Viral
12.
Acta Pharm Sin B ; 8(3): 371-380, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29881676

RESUMEN

Compared to conventional cancer treatment, combination therapy based on well-designed nanoscale platforms may offer an opportunity to eliminate tumors and reduce recurrence and metastasis. In this study, we prepared multifunctional microspheres loading 131I-labeled hollow copper sulfide nanoparticles and paclitaxel (131I-HCuSNPs-MS-PTX) for imaging and therapeutics of W256/B breast tumors in rats. 18F-fluordeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) imaging detected that the expansion of the tumor volume was delayed (P<0.05) following intra-tumoral (i.t.) injection with 131I-HCuSNPs-MS-PTX plus near-infrared (NIR) irradiation. The immunohistochemical analysis further confirmed the anti-tumor effect. The single photon emission computed tomography (SPECT)/photoacoustic imaging mediated by 131I-HCuSNPs-MS-PTX demonstrated that microspheres were mainly distributed in the tumors with a relatively low distribution in other organs. Our results revealed that 131I-HCuSNPs-MS-PTX offered combined photothermal, chemo- and radio-therapies, eliminating tumors at a relatively low dose, as well as allowing SPECT/CT and photoacoustic imaging monitoring of distribution of the injected agents non-invasively. The copper sulfide-loaded microspheres, 131I-HCuSNPs-MS-PTX, can serve as a versatile theranostic agent in an orthotopic breast cancer model.

13.
Oncotarget ; 9(26): 18327-18340, 2018 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-29719608

RESUMEN

ß3GnT8, a key polylactosamine synthase, plays a vital role in progression of various types of human cancer. The role of ß3GnT8 in hepatocellular carcinoma (HCC) and the underlying mechanisms, however, remain largely unknown. In this study, we found that ß3GnT8 and polylactosamine were highly expressed in HCC tissues compared with those in adjacent paracancer tissues. Overexpression of ß3GnT8 promoted while knockdown of ß3GnT8 inhibited HCC cell invasion and migration in vitro. Importantly, enhanced tumorigenesis was observed in nude mice inoculated with ß3GnT8-overexpressing HCC cells, suggesting that ß3GnT8 is important for HCC development in vitro and in vivo. Mechanistically, ß3GnT8 modulated the N-glycosylation patterns of CD147 and altered the polylactosamine structures in HCC cells by physically interacting with CD147. In addition, our data showed the c-Jun could directly bind to the promoter of ß3GnT8 gene and regulate ß3GnT8 expression. ß3GnT8 regulated HCC cell invasion and migration in a C-Jun-dependent manner. Collectively, our study identified ß3GnT8 as a novel regulator for HCC invasion and tumorigenesis. Targeting ß3GnT8 may be a potential therapeutic strategy against HCC.

14.
Oncol Lett ; 14(3): 3722-3728, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28927138

RESUMEN

ß-1,3-N-Acetylglucosaminyltransferase 8 (ß3GnT8) is a key enzyme that catalyzes the formation of polylactosamine glycan structures by transferring GlcNAc to tetra-antennary ß1-6-branched N-glycans, and it has been reported to participate in tumor invasion and metastasis by regulating the expression of matrix metalloproteinases (MMPs), cluster of differentiation 147 (CD147) and polylactosamine. By contrast, the role of transcription factor c-Jun in cell cycle progression has been well established. c-Jun has an important role in tumor cell invasion and metastasis. However, the precise molecular mechanisms by which c-Jun regulates these processes in colorectal carcinoma cells are not fully elucidated. In the present study, c-Jun had a significant effect on the invasive and migratory abilities of SW480 and LoVo cells. Additionally, overexpression of c-Jun was able to increase the expression of ß3GnT8, MMPs, CD147 and polylactosamine. Similarly, knockdown of c-Jun was able to decrease the expression of ß3GnT8, MMPs, CD147 and polylactosamine. These results suggest that c-Jun is able to regulate colorectal carcinoma cell invasion and metastasis via ß3GnT8. A chromatin immunoprecipitation assay indicated that c-Jun is able to bind directly to the promoter regions of ß3GnT8 in SW480 and LoVo cells. This leads to transcriptional activation of ß3GnT8, which in turn regulates the expression of tumor invasion and metastasis-associated genes. The results of the present study demonstrate a novel mechanism underlying colorectal carcinoma cell invasion and metastasis, where ß3GnT8 is transcriptionally activated via c-Jun binding to its promoter.

15.
Mol Med Rep ; 15(6): 3724-3734, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28393207

RESUMEN

Glycopeptide-preferring polypeptide N-acetylgalactosamine transferase (ppGalNAc­T) is a key enzyme that initiates the formation of the first GalNAc monosaccharide to polypeptides at Thr/Ser residues by O­linked glycosylation. In order to investigate the effects of ppGalNAc­T1 and ppGalNAc­T2 on the initiation of O­glycosylation, siRNA­ppGalNAc­T1 (si­T1) and siRNA­ppGalNAc­T2 (si­T2) were transfected into highly­invasive estrogen receptor­negative MDA­MB­231 cells to inhibit O­glycosylation. Downregulation of ppGalNAc­T1 demonstrated a significant reduction in the number of terminal α2,3 sialic acids, when compared to cells transfected with si­T2 or si­T1/T2. This downregulation led to a decrease in the invasion capabilities of the breast carcinoma cells, as well as enhanced chemosensitivity, which was the result antineoplastic drug effects. In addition, immunoprecipitation assays demonstrated that downregulation of ppGalNAc­T1 led to a reduction in the number of terminal α2,3 sialic acids on O­linked glycans of the matrix metalloproteinase­14 (MMP14) glycoprotein. Furthermore, MMP14 and vascular endothelial growth factor were downregulated in the si­T1 groups when compared with the si­T2 and si­T1/T2 groups. In conclusion, the results of the present study suggest that ppGalNAc­T1 may serve a pivotal role in the initiation of O­glycosylation, which may lead to a low density of α2,3 sialic acids on O­linked glycans of MMP14 when downregulated. Glycosylation serves a significant role in regulating the sensitivity of MMP14 to self­proteolysis, which ultimately decreases the invasion capabilities of breast cancer cells. The results of the present study may be useful in establishing the function of ppGalNAc­T1 during breast cancer invasion and metastasis.


Asunto(s)
Resistencia a Antineoplásicos/genética , Metaloproteinasa 14 de la Matriz/genética , N-Acetilgalactosaminiltransferasas/genética , Interferencia de ARN , Neoplasias de la Mama Triple Negativas/genética , Antineoplásicos/farmacología , Movimiento Celular/genética , Proliferación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica , Silenciador del Gen , Glicosilación , Humanos , ARN Interferente Pequeño/genética , Ácidos Siálicos/metabolismo , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo , Neoplasias de la Mama Triple Negativas/metabolismo , Neoplasias de la Mama Triple Negativas/patología , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Polipéptido N-Acetilgalactosaminiltransferasa
16.
Mol Divers ; 18(2): 403-9, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24515340

RESUMEN

Here, we describe the structural optimization of a known EGFR inhibitor (compound 1) that showed weak off-target activity against RET. Twenty-six analogs of 1 were synthesized. SAR analysis led to the discovery of several compounds that showed considerable potency against the RET-dependent thyroid cancer cell line TT. Kinase inhibitory potency was then measured for the most active compound (2u) in the cellular assay. The results showed that 2u is a potent RET inhibitor with an IC(50) value of 7 nM.


Asunto(s)
Descubrimiento de Drogas , Receptores ErbB/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-ret/antagonistas & inhibidores , Células Hep G2 , Humanos , Concentración 50 Inhibidora , Relación Estructura-Actividad
17.
J Biomol Struct Dyn ; 31(2): 215-23, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22831459

RESUMEN

C5aR antagonists have been thought as potential immune mediators in various inflammatory and autoimmune diseases, and discovery of C5aR antagonists has attracted much attention in recent years. The discovery of C5aR antagonists was usually achieved through high-throughput screening, which usually suffered a high cost and a low success rate. Currently, the fast developing computer-aided virtual screening (VS) methods provide economic and rapid approaches to the lead discovery. In this account, we proposed a hybrid ligand-based VS protocol that is based on support vector machine (SVM) classification and pharmacophore models for retrieving novel C5aR antagonists. Performance evaluation of this hybrid VS protocol in virtual screening against a large independent test set, T-CHEM, showed that the hybrid VS approach significantly increased the hit rate and enrichment factor compared with the individual SVM classification model-based VS and pharmacophore model-based VS, as well as molecular docking-based VS in that the receptor structure was created by homology modeling. The hybrid VS approach was then used to screen several large chemical libraries including PubChem, Specs, and Enamine. Finally, a total of 20 compounds were selected from the top ranking hits, and shifted to the subsequent in vitro and in vivo studies, which results will be reported in the near future.


Asunto(s)
Inactivadores del Complemento/química , Simulación del Acoplamiento Molecular , Receptores de Complemento/antagonistas & inhibidores , Evaluación Preclínica de Medicamentos/métodos , Humanos , Concentración 50 Inhibidora , Ligandos , Modelos Químicos , Receptor de Anafilatoxina C5a , Receptores de Complemento/química , Bibliotecas de Moléculas Pequeñas , Homología Estructural de Proteína , Máquina de Vectores de Soporte
18.
Chem Biol Drug Des ; 81(2): 175-84, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23107363

RESUMEN

In this investigation, a common feature pharmacophore model of anaplastic lymphoma kinase inhibitors was developed based on several known anaplastic lymphoma kinase inhibitors that were co-crystallized with anaplastic lymphoma kinase. The established pharmacophore model Hypo1 was carefully validated and then adopted to screen two in silico chemical databases, Specs (202 408 compounds) and Enamine (1 105 894 compounds), for retrieving novel anaplastic lymphoma kinase inhibitors. The hit compounds were further filtered using a fast bumping-check tool and molecular docking. Finally, 25 compounds were selected and purchased from market. The bioactivity of these compounds was firstly measured at the cellular level against a typical anaplastic lymphoma kinase mutant-driven cancer cell line, Karpas299. And six of them showed a good anti-viability activity. The kinase inhibitory potency against the recombinant human anaplastic lymphoma kinase kinase was tested to the most active compound at the cellular level, T0508-5181 (from Specs), which gave a half maximal inhibitory concentration (IC(50)) of 5.3 µM.


Asunto(s)
Antineoplásicos/química , Inhibidores de Proteínas Quinasas/química , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Quinasa de Linfoma Anaplásico , Antineoplásicos/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Ligandos , Simulación del Acoplamiento Molecular , Mutación , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas Receptoras/química , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo , Relación Estructura-Actividad
19.
Eur J Med Chem ; 56: 30-8, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22944772

RESUMEN

Aberrant activation of casein kinase 1 (CK1) has been demonstrated to be implicated in the pathogenesis of cancer and various central nervous system disorders. Discovery of CK1 inhibitors has thus attracted much attention in recent years. In this account, we describe the discovery of N6-phenyl-1H-pyrazolo[3,4-d]pyrimidine-3,6-diamine derivatives as novel CK1 inhibitors. An optimal common-feature pharmacophore hypothesis, termed Hypo2, was firstly generated, followed by virtual screening using Hypo2 against several chemical databases. One of the best hit compounds, N6-(4-chlorophenyl)-1H-pyrazolo[3,4-d]pyrimidine-3,6-diamine, was chosen for the subsequent hit-to-lead optimization under the guide of Hypo2, which led to the discovery of a new lead compound (1-(3-(3-amino-1H-pyrazolo[3,4-d]pyrimidin-6-ylamino)phenyl)-3-(3-chloro-4-fluorophenyl)urea) that potently inhibits CK1 with an IC(50) value of 78 nM.


Asunto(s)
Quinasa de la Caseína I/antagonistas & inhibidores , Diaminas/farmacología , Descubrimiento de Drogas , Inhibidores de Proteínas Quinasas/farmacología , Pirimidinas/farmacología , Quinasa de la Caseína I/metabolismo , Diaminas/síntesis química , Diaminas/química , Relación Dosis-Respuesta a Droga , Ensayos Analíticos de Alto Rendimiento , Modelos Moleculares , Estructura Molecular , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Pirimidinas/síntesis química , Pirimidinas/química , Relación Estructura-Actividad
20.
Chem Biol Drug Des ; 80(3): 366-73, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22594639

RESUMEN

Bruton's tyrosine kinase has emerged as a potential target for the treatment for B-cell malignancies and autoimmune diseases. Discovery of Bruton's tyrosine kinase inhibitors has thus attracted much attention recently. In this investigation, we introduced a hybrid protocol of virtual screening methods including support vector machine model-based virtual screening, pharmacophore model-based virtual screening and docking-based virtual screening for retrieving new Bruton's tyrosine kinase inhibitors from commercially available chemical databases. Performances of the hybrid virtual screening approach were evaluated against a test set, which results showed that the hybrid virtual screening approach significantly shortened the overall screening time, and considerably increased the hit rate and enrichment factor compared with the individual method (SB-VS, PB-VS and DB-VS) or their combinations by twos. This hybrid virtual screening approach was then applied to screen several chemical databases including Specs (202,408 compounds) and Enamine (980,000 compounds) databases. Thirty-nine compounds were selected from the final hits and have been shifted to experimental studies.


Asunto(s)
Diseño de Fármacos , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Agammaglobulinemia Tirosina Quinasa , Bases de Datos Factuales , Humanos , Modelos Moleculares , Proteínas Tirosina Quinasas/metabolismo , Relación Estructura-Actividad , Máquina de Vectores de Soporte
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