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1.
Gene ; 727: 144232, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31715300

RESUMO

Colorectal cancer (CRC) is a global disease with high incidence and mortality rate. Hsp90 inhibitors induce cell death in various cancers, including CRC. However, the underlying mechanisms need to be clarified further. In this study, Caco-2 cells were treated with 0.25 µM SNX-2112, an Hsp90 inhibitor, for 48 h; subsequently, whole-transcriptome sequencing was performed. At the mRNA level in SNX-2112-treated Caco-2 cells, 1588 genes were upregulated, and 433 genes were downregulated. Six genes were found to be associated with necroptosis and apoptosis, and these 6 upregulated genes were validated by RT-qPCR. Hundred and six miRNAs were upregulated, and 48 miRNAs were downregulated in SNX-2112-treated Caco-2 cells. Eleven downregulated miRNAs were found to interact with the 6 upregulated genes. Moreover, 676 circRNAs were upregulated, and 291 circRNAs were downregulated in SNX-2112-treated Caco-2 cells. Among them, 126 circRNAs were found to be the target of the 11 downregulated miRNAs. The circRNA-miRNA-mRNA regulatory network of Hsp90 inhibitor-induced cell death in colorectal cancer was constructed. This regulatory network extends the underlying mechanism of Hsp90 and improves our understanding of Hsp90 inhibitors as potential targeted therapeutic agents.


Assuntos
Neoplasias Colorretais/genética , Redes Reguladoras de Genes/genética , Células CACO-2 , Neoplasias do Colo/genética , Neoplasias Colorretais/metabolismo , Regulação para Baixo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/genética , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , MicroRNAs/genética , Análise de Sequência com Séries de Oligonucleotídeos , RNA/genética , RNA/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Regulação para Cima
2.
PeerJ ; 7: e7705, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31598423

RESUMO

Background: Esophageal squamous cell carcinoma (ESCC) is a subtype of esophageal cancer with high incidence and mortality. Due to the poor 5-year survival rates of patients with ESCC, exploring novel diagnostic markers for early ESCC is emergent. Collagen, the abundant constituent of extracellular matrix, plays a critical role in tumor growth and epithelial-mesenchymal transition. However, the clinical significance of collagen genes in ESCC has been rarely studied. In this work, we systematically analyzed the gene expression of whole collagen family in ESCC, aiming to search for ideal biomarkers. Methods: Clinical data and gene expression profiles of ESCC patients were collected from The Cancer Genome Atlas and the gene expression omnibus databases. Bioinformatics methods, including differential expression analysis, survival analysis, gene sets enrichment analysis (GSEA) and co-expression network analysis, were performed to investigate the correlation between the expression patterns of 44 collagen family genes and the development of ESCC. Results: A total of 22 genes of collagen family were identified as differentially expressed genes in both the two datasets. Among them, COL1A1, COL10A1 and COL11A1 were particularly up-regulated in ESCC tissues compared to normal controls, while COL4A4, COL6A5 and COL14A1 were notably down-regulated. Besides, patients with low COL6A5 expression or high COL18A1 expression showed poor survival. In addition, a 7-gene prediction model was established based on collagen gene expression to predict patient survival, which had better predictive accuracy than the tumor-node-metastasis staging based model. Finally, GSEA results suggested that collagen genes might be tightly associated with PI3K/Akt/mTOR pathway, p53 pathway, apoptosis, cell cycle, etc. Conclusion: Several collagen genes could be potential diagnostic and prognostic biomarkers for ESCC. Moreover, a novel 7-gene prediction model is probably useful for predicting survival outcomes of ESCC patients. These findings may facilitate early detection of ESCC and help improves prognosis of the patients.

3.
Nat Prod Res ; : 1-9, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31264446

RESUMO

Two new cembrane diterpenoids, named populeuphrines A and B (1 and 2), together with three known analogues (3-5) were isolated from the resins of Populus euphratica. The planar structures and relative configurations of 1 and 2 were elucidated by detailed 1 D and 2 D NMR spectroscopic analyses. The absolute configurations of 1 and 2 were determined by X-ray diffraction analysis and quantum chemical computation. Biological activities of all the isolates against proliferation of human cancer cells and umbilical cord mesenchymal stem cells were evaluated.

4.
Nat Prod Res ; : 1-7, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31264475

RESUMO

A new eudesmane sesquiterpenoid, artemisargin A (1), two new guaianolide sesquiterpenoids, artemisargins B (2) and C (3), along with three known sesquiterpenoids (4-6), were isolated from the leaves of Artemisia argyi. Their structures were determined by extensive spectroscopic methods and electronic circular dichroism calculations. Biological evaluation showed that 1 could inhibit the growth of cancer cells, especially in BGC-823 cells with an IC50 value of 49.87 µM.

5.
Int J Pharm ; 566: 101-110, 2019 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-31103820

RESUMO

Chitosan (CS) is a biodegradable and biocompatible polysaccharide which displays immune-stimulatory effects and anti-bacterial properties to facilitate wound closure. Over the years, different CS-based dressings have been developed; however, most of them are not fully biodegradable due to the involvement of synthetic polymers during dressing fabrication. In addition, preparation of many of these dressings is laborious, and may impose damaging effects on fragile therapeutic molecules. The objective of this study is to address these problems by developing a tunable, biocompatible, and biodegradable CS-based dressing for wound treatment. The dressing is fabricated via electrostatic interactions between CS and carmellose (CM). Its swelling properties, erosion behavior, loading efficiency and drug release sustainability can be tuned by simply changing the CS/CM mass-to-mass ratio. Upon loaded with minocycline hydrochloride, the dressing effectively protects the wound in mice from infection and enhances wound closure. Regarding its high tunability and promising in vivo performance, our dressing warrants further development as a user-friendly dressing for use in wound care.


Assuntos
Antibacterianos/administração & dosagem , Bandagens , Carboximetilcelulose Sódica/administração & dosagem , Quitosana/administração & dosagem , Sistemas de Liberação de Medicamentos , Minociclina/administração & dosagem , Células 3T3 , Animais , Antibacterianos/química , Carboximetilcelulose Sódica/química , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Feminino , Camundongos , Camundongos Endogâmicos ICR , Minociclina/química , Polieletrólitos/administração & dosagem , Polieletrólitos/química , Eletricidade Estática , Cicatrização
6.
Fitoterapia ; 134: 382-388, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30890423

RESUMO

Diverse terpenoids including a novel sesquiterpenoidal lactam, commipholactam A (1), and a structurally related new cadinane sesquiterpenoid, commiphorane H (2), a new eudesmane sesquiterpenoid, commiphorane I (4), a new guaiane sesquiterpenoid, commiphorane J (5), and two new nor-abietane diterpenoids, commiphoranes K1 and K2 (6 and 7) along with two known terpenoids (3 and 8), were isolated from Resina Commiphora. Their structures with absolute configurations were characterized by spectroscopic methods and calculated electronic circular dichroism (ECD). Notably, commipholactam A represents the first example of cadinane sesquiterpene alkaloids isolated from Resina Commiphora. Biological assessment toward human cancer cells showed that the IC50 values of 1 against HepG2 and A549 cells were 21.73 µM and 128.50 µM, respectively.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Commiphora/química , Sesquiterpenos/farmacologia , Células A549 , /farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , China , Células Hep G2 , Humanos , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Sesquiterpenos/isolamento & purificação , Sesquiterpenos de Guaiano/isolamento & purificação , Sesquiterpenos de Guaiano/farmacologia , Terpenos/isolamento & purificação , Terpenos/farmacologia
7.
Int J Biol Sci ; 15(2): 312-324, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30745823

RESUMO

Gastric cancer stem cell (GCSC) is implicated in gastric cancer relapse, metastasis and drug resistance. However, the key molecule(s) involved in GCSC survival and the targeting drugs are poorly understood. We discovered increased secreted clusterin (S-Clu) protein expression during the sphere-forming growth of GCSC via mass spectrometry. Overexpression of clusterin was detected in 69/90 (77%) of primary GC tissues and significantly associated with T stage, lymph node metastasis and TNM stage. Depletion of clusterin (Clu, the full-length intracellular clusterin) led to the declustering of GCSC tumorspheres and apoptosis of GCSC. Subsequently, we found clusterin was in complex with heat shock protein 90 beta (HSP90) and involved in regulating the cellular level of HSP90 client proteins. Furthermore, by screening a collection of drugs/inhibitors, we found that verteporfin (VP), a phototherapy drug, blocked clusterin gene expression, decreased the HSP90 client proteins and caused cell death of GCSC. VP treatment is more effective in eradicating GCSCs than in killing GC cells. Both clusterin silencing or VP treatment deterred tumor growth in human GCSC xenografts. These findings collectively suggest that GC patients can promptly benefit from clusterin-targeted therapy as well as VP treatment in combination with or subsequent to conventional chemotherapy for reducing mortality of GC.


Assuntos
Clusterina/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Verteporfina/farmacologia , Verteporfina/uso terapêutico , Animais , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Imunoprecipitação , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos BALB C , Ligação Proteica/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Molecules ; 25(1)2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31906049

RESUMO

Five new meroterpenoids, zizhines P-S and U (1-4,7), together with two known meroterpenoids (5 and 6) were isolated from Ganoderma sinensis. Their structures including absolute configurations were assigned by using spectroscopic, computational, and chemical methods. Racemics zizhines P and Q were purified by HPLC on chiral phase. Biological evaluation found that 4, 5 and 6 are cytotoxic toward human cancer cells (A549, BGC-823, Kyse30) with IC50 values in the range of 63.43-80.83 µM towards A549, 59.2 ± 2.73 µM and 64.25 ± 0.37 µM towards BGC-823, 76.28 ± 1.93 µM and 85.42 ± 2.82 µM towards Kyse30.

9.
Molecules ; 23(12)2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30544580

RESUMO

A novel sesquiterpene dimer, spirocommiphorfuran A (1); two new cadinane sesquiterpenoids, commiphorenes A (2) and B (3); along with three known terpenoids (4⁻6), were isolated from Resina Commiphora. The structures of these new compounds were characterized by NMR, HRESIMS, quantum chemical computation, and X-ray diffraction analysis. Compound 1 features a 7-oxabicyclo[2.2.1]heptane-2-ene core, representing the first example of germacrane-type sesquiterpene dimer fused via a spiro ring system. Compound 2 is a novel sesquiterpene with a completely new carbon skeleton, which is characteristic of an additional carbon attaching to the cadinane backbone via a carbon⁻carbon bond. Additionally, compounds 2 and 4 exert acceptable cytotoxicity toward normal cells and high selectivity in cancer cells, especially in HepG2 cells.


Assuntos
Burseraceae/química , Terpenos/farmacologia , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Dicroísmo Circular , Humanos , Concentração Inibidora 50 , Espectroscopia de Prótons por Ressonância Magnética , Terpenos/química
10.
Mikrochim Acta ; 185(8): 375, 2018 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-30008087

RESUMO

An innovative signal amplification strategy assisted by RNase H is described here for the detection of DNA targets in a universal fashion. A tailor-made RNA molecular beacon (RMB) conjugated with a fluorescence resonance energy transfer (FRET) pair (fluorophore and quencher) was designed, characterized, and combined with the employment of RNase H. Its performance is compared to that of other nucleases including Exonuclease III and T7 exonuclease. Fluorometry, performed best at excitation/emission wavelengths of 490/520 nm, gives an amazingly low detection limit of 23 fM for target DNA. The method was verified by the determination of human hemochromatosis (HFE) gene. It is perceived that the method represents a versatile tool for the detection of a wide range of targets. Graphical Abstract An RNase H-assisted signal amplification (RASA) method for the fluorometric assay of nucleic acids has been developed by using a unique RNA molecular beacon (RNA MB) conjugated with a fluorophore (F) and quencher (Q) pair for signal generation.


Assuntos
DNA/análise , Fluorometria/métodos , Limite de Detecção , Sondas de Oligonucleotídeos/metabolismo , Ribonuclease H/metabolismo , DNA/metabolismo , Hemocromatose/genética , Humanos , Conformação de Ácido Nucleico , Sondas de Oligonucleotídeos/química
11.
Exp Cell Res ; 370(1): 58-67, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29894706

RESUMO

CD44, a glycoprotein, has been reported to have relationship with resistance to radiation in prostate cancer (Cap) cells. However, its molecular mechanism remains unknown. In this study, we demonstrated that inhibited CD44 enhanced the radiosentivity in Cap cells. It has been hypothesized that CD44 combine with ERBB2 and activate downstream phosphated protein to mediate DNA damage repair. Therefore, we conducted a detailed analysis of effects of radiation by clonogenic assay and immunofluorescence stain for p-H2AX foci. The downstream of CD44/ERBB2 and DNA damage repair proteins was detected by western blot. The results reveal that CD44 interacted with ERBB2, the downstream of CD44/ERBB2 was p-p38 when Cap cells were irradiated. Among the pathways, homologous recombination (HR) related proteins Mre11 and Rad50 were involved in CD44/ERBB2/p-p38 mediated radioresistance in Cap. In conclusion, CD44 could stabilize ERBB2 and co-activate p-p38 expression then promote the DNA damage repair by HR pathway, which finally contribute to the radioresistance of CaP.


Assuntos
Recombinação Homóloga/genética , Receptores de Hialuronatos/genética , Sistema de Sinalização das MAP Quinases/genética , Fosforilação/genética , Neoplasias da Próstata/genética , Tolerância a Radiação/genética , Receptor ErbB-2/genética , Linhagem Celular Tumoral , DNA/genética , Reparo do DNA/genética , Humanos , Masculino
12.
Virus Genes ; 54(3): 343-350, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29541932

RESUMO

Herpes simplex virus 1 (HSV-1) encodes various microRNAs (miRNAs), whose targets are largely unknown. miR-H1 is the first discovered HSV-1 miRNA and is expressed predominantly in productive infection. Here we show that ubiquitin protein ligase E3 component n-recognin 1 (Ubr1) is a cellular target of miR-H1. Ubr1 is a RING-type E3 ubiquitin ligase of the Arg/N-end rule pathway, which causes the degradation of proteins bearing "destabilizing" N-terminal residues, such as neurodegeneration-associated protein fragment ß-amyloid. Using model substrates, we found that miR-H1 significantly repressed the expression and activity of Ubr1. Consequently, miR-H1-mediated Ubr1 silencing resulted in the accumulation of ß-amyloid, which might contribute to the neurodegenerative pathogenesis enhanced by HSV-1. Our results provide novel insights into the mechanism by which HSV-1-encoded miR-H1 functions in neurodegenerative pathogenesis through targeting Ubr1-mediated Arg/N-end rule degradation pathway.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Herpesvirus Humano 1/fisiologia , MicroRNAs/fisiologia , RNA Viral/fisiologia , Ubiquitina-Proteína Ligases/metabolismo , Células HEK293 , Humanos , MicroRNAs/biossíntese , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , RNA Viral/biossíntese , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/antagonistas & inibidores
13.
Biochem Biophys Res Commun ; 493(1): 534-541, 2017 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-28867195

RESUMO

PI3K pathway is an important anti-tumor target, but its effect and mechanism is not clear in esophageal squamous cell carcinoma (ESCC). By analysis of the Cancer Genome Atlas (TCGA) datasets, we found that PI3Ks level were significantly upregulated in human esophageal cancer tissues compared with that in non-cancer tissues. The alteration of PI3K can significantly affect the overall patient survival in ESCC but not in esophageal adenocarcinoma (EAC). We found that the classic PI3K inhibitor LY294002 obviously inhibited the canonical mammalian target of rapamycin (mTOR) pathway and restrained the growth of ESCC with less toxicity to normal cells. Besides, LY294002 inhibited noncanonical PKR-like ER kinase (PERK)/elF2α/ATF4 pathway as well. Both siRNA and the small molecule inhibitor GSK2656157 against PERK/elF2α/ATF4 pathway can significantly inhibit the growth of ESCC. More importantly, GSK2656157 aggravated the inhibitory effect of LY294002 on cell growth, colony formation, and apoptosis induction of ESCC. In addition of dual high expression of PI3K and PERK pathways in the ESCC patients, the difference of overall survival (OS) was more significant than using PI3K alone. These results indicated that dual targeting of PI3K and PERK pathways might improve clinical prognosis and enhance the treatment of ESCC patients.


Assuntos
Adenina/análogos & derivados , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/metabolismo , Indóis/administração & dosagem , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , eIF-2 Quinase/metabolismo , Adenina/administração & dosagem , Idoso , Antineoplásicos/administração & dosagem , Carcinoma de Células Escamosas/mortalidade , China/epidemiologia , Neoplasias Esofágicas/mortalidade , Carcinoma de Células Escamosas do Esôfago , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Prognóstico , Taxa de Sobrevida , Resultado do Tratamento , eIF-2 Quinase/antagonistas & inibidores
14.
Int J Oncol ; 50(1): 101-110, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27909720

RESUMO

Cancer stem cells (CSCs) in glioma are often responsible for relapse and resistance to therapy. The purpose of the present study was to confirm the self-renewal and migration inhibitory effects of tetrandrine (Tet), which is a compound extracted from the dried root of Stephania tetrandra S. Moore, toward glioma stem-like cells (GSLCs) and to examine the associated molecular mechanisms. Using a neurosphere culture technique, we enriched the GSLC population from the human glioblastoma cell lines U87 and U251. Cells were analyzed using cell counting kit-8 (CCK-8), western blotting, flow cytometry, transwell assay and immunofluorescence staining. GSLCs displayed properties of neural stem cells, including elevated expression of the cancer stem cell marker ALDH1 and ß-catenin. We found that Tet treatment decreased sphere formation in GSLCs in a dose-dependent manner using tumor spheroid formation assay. The GSK3ß inhibitor BIO maintained sphere formation and migration capacity in GSLCs, whereas the ß-catenin/TCF transcription inhibitor ICG-001 decreased sphere formation and the migration capacity of GSLCs. The proportion of apoptotic GSLCs also increased in response to ICG-001 treatment. These results indicate that ß-catenin activity is vital in maintaining neural stem cell traits of GSLCs. Tet inhibits cell viability, neurosphere formation and migration of GSLCs in vitro. Importantly, Tet treatment significantly repressed the nuclear translocation and expression of ß-catenin and induced apoptosis in GSLCs, as indicated in part by the upregulation of Bax, the cleavage of PARP and the downregulation of Bcl-2. The present study demonstrates that the inhibition of ß-catenin in CSCs by Tet could be an effective strategy for the treatment of glioma.


Assuntos
Benzilisoquinolinas/administração & dosagem , Glioma/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , beta Catenina/biossíntese , Apoptose/efeitos dos fármacos , Compostos Bicíclicos Heterocíclicos com Pontes/administração & dosagem , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioma/genética , Glioma/patologia , Humanos , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Pirimidinonas/administração & dosagem , Proteína X Associada a bcl-2/biossíntese , beta Catenina/antagonistas & inibidores , beta Catenina/genética
15.
Autophagy ; 12(9): 1593-613, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27310928

RESUMO

Modulation of autophagy has been increasingly regarded as a promising cancer therapeutic approach. In this study, we screened several ginsenosides extracted from Panax ginseng and identified ginsenoside Ro (Ro) as a novel autophagy inhibitor. Ro blocked the autophagosome-lysosome fusion process by raising lysosomal pH and attenuating lysosomal cathepsin activity, resulting in the accumulation of the autophagosome marker MAP1LC3B/LC3B and SQSTM1/p62 (sequestosome 1) in various esophageal cancer cell lines. More detailed studies demonstrated that Ro activated ESR2 (estrogen receptor 2), which led to the activation of NCF1/p47(PHOX) (neutrophil cytosolic factor 1), a subunit of NADPH oxidase, and subsequent reactive oxygen species (ROS) production. Treatment with siRNAs or inhibitors of the ESR2-NCF1-ROS axis, such as N-acetyl-L-cysteine (NAC), diphenyleneiodonium chloride (DPI), apocynin (ACN), Tiron, and Fulvestrant apparently decreased Ro-induced LC3B-II, GFP-LC3B puncta, and SQSTM1, indicating that ROS instigates autophagic flux inhibition triggered by Ro. More importantly, suppression of autophagy by Ro sensitized 5-fluorouracil (5-Fu)-induced cell death in chemoresistant esophageal cancer cells. 5-Fu induced prosurvival autophagy, and by inhibiting such autophagy, siRNAs against BECN1/beclin 1, ATG5, ATG7, and LC3B enhanced 5-Fu-induced autophagy-associated and apoptosis-independent cell death. We observed that Ro potentiates 5-Fu cytotoxicity via delaying CHEK1 (checkpoint kinase 1) degradation and downregulating DNA replication process, resulting in the delayed DNA repair and the accumulation of DNA damage. In summary, these data suggest that Ro is a novel autophagy inhibitor and could function as a potent anticancer agent in combination therapy to overcome chemoresistance.


Assuntos
Autofagossomos/metabolismo , Quinase 1 do Ponto de Checagem/metabolismo , Dano ao DNA , Neoplasias Esofágicas/metabolismo , Ginsenosídeos/química , Lisossomos/metabolismo , Animais , Apoptose , Autofagia , Ciclo Celular , Sobrevivência Celular , Receptor beta de Estrogênio/metabolismo , Fluoruracila/farmacologia , Proteínas de Fluorescência Verde/metabolismo , Humanos , Camundongos , NADPH Oxidases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Células Vero
16.
Drug Metab Pharmacokinet ; 30(6): 425-33, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26611713

RESUMO

Excretion of sulfate metabolites is an essential process in disposition of raloxifene via the sulfonation pathway. However, the transporters responsible for excretion of raloxifene sulfates remain undefined. Here, sulfonation of raloxifene and excretion of its sulfate metabolites were investigated using SULT1A3-overexpressing HEK293 cells (or SULT293 cells) with significant expression of BCRP and MRP4. SULT293 cell lysate catalyzed the sulfonation of raloxifene at both 6-OH and 4'-OH groups, generating raloxifene-6-sulfate (R-6-S) and raloxifene-4'-sulfate (R-4'-S), respectively. Sulfate formation followed the Michaelis-Menten kinetics (Km = 0.49 µM and Vmax = 5.79 pmol/min/mg for R-6-S; Km = 0.33 µM and Vmax = 1.25 pmol/min/mg for R-4'-S). As expected, the recombinant SULT1A3 enzyme showed a high similarity in raloxifene sulfonation profiles with the lysate preparation. Ko143, a selective inhibitor of BCRP, significantly decreased the excretion rates of raloxifene sulfates (maximal 66.1%) while increasing the intracellular sulfates (maximal 282%). As a result, the apparent efflux clearance (CLef,app, representing the efflux efficiency of raloxifene sulfates) was substantially reduced (maximal 85.6%). Likewise, the pan-MRP inhibitor MK-571 significantly deceased the excretion rates (maximal 69.6%) and CLef,app values (maximal 96.0%) of raloxifene sulfates while increasing the intracellular sulfates (maximal 667%). Further, the short-hairpin RNA (shRNA) targeting BCRP significantly reduced (maximal 35.0%) sulfate excretion. Use of BCRP shRNA also caused significant decreases (maximal 52.5%) in the CLef,app values. Silencing of MRP4 by shRNA led to a substantial alteration in sulfate disposition (i.e., 28.6-37.8% reductions in sulfate excretion, 30.5-59.3% elevations in intracellular sulfates, and 44.8-47.7% deceases in CLef,app values). In conclusion, two sulfate metabolites R-6-S and R-4'-S were generated from raloxifene in SULT293 cells. Cellular excretion of the raloxifene sulfates was mainly mediated by BCRP and MRP4.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Arilsulfotransferase/biossíntese , Proteínas Associadas à Resistência a Múltiplos Medicamentos/sangue , Proteínas de Neoplasias/metabolismo , Cloridrato de Raloxifeno/metabolismo , Moduladores Seletivos de Receptor Estrogênico/metabolismo , Sulfatos/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Transportadores de Cassetes de Ligação de ATP/genética , Arilsulfotransferase/genética , Transporte Biológico , Dicetopiperazinas/farmacologia , Indução Enzimática , Células HEK293 , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , Cinética , Desintoxicação Metabólica Fase II , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Propionatos/farmacologia , Quinolinas/farmacologia , Interferência de RNA , Transfecção
17.
Mol Cancer ; 14: 56, 2015 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-25890196

RESUMO

BACKGROUND: Acute myeloid leukemia (AML) is initiated and maintained by a subset of self-renewing leukemia stem cells (LSCs), which contribute to the progression, recurrence and therapeutic resistance of leukemia. However, the mechanisms underlying the maintenance of LSCs drug resistance have not been fully defined. In this study, we attempted to elucidate the mechanisms of LSCs drug resistance. METHODS: We performed reverse phase protein arrays to analyze the expression of anti-apoptotic proteins in the LSC-enriched leukemia cell line KG-1a. Immuno-blotting, cell viability and clinical AML samples were evaluated to verify the micro-assay results. The characteristics and transcriptional regulation of survivin were analyzed with the relative luciferase reporter assay, mutant constructs, chromatin immuno-precipitation (ChIP), quantitative real-time reverse transcription polymerase chain reaction (RT-qPCR), and western blotting. The levels of Sp1, c-Myc, phospho-extracellular signal-regulated kinase (p-ERK), phospho-mitogen and stress-activated protein kinase (p-MSK) were investigated in paired CD34+ and CD34- AML patient samples. RESULTS: Survivin was highly over-expressed in CD34 + CD38- KG-1a cells and paired CD34+ AML patients compared with their differentiated counterparts. Functionally, survivin contributes to the drug resistance of LSCs, and Sp1 and c-Myc concurrently regulate levels of survivin transcription. Clinically, Sp1 and c-Myc were significantly up-regulated and positively correlated with survivin in CD34+ AML patients. Moreover, Sp1 and c-Myc were further activated by the ERK/MSK mitogen-activated protein kinase (MAPK) signaling pathway, modulating survivin levels. CONCLUSION: Our findings demonstrated that ERK/MSK/Sp1/c-Myc axis functioned as a critical regulator of survivin expression in LSCs, offering a potential new therapeutic strategy for LSCs therapy.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Proteínas Inibidoras de Apoptose/genética , Leucemia Mieloide Aguda/genética , Sistema de Sinalização das MAP Quinases/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Proteínas Proto-Oncogênicas c-myc/genética , Fator de Transcrição Sp1/genética , Adulto , Antígenos CD34/genética , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Feminino , Células HL-60 , Humanos , Células K562 , Masculino , Células-Tronco Neoplásicas/metabolismo , Transdução de Sinais/genética , Survivina , Transcrição Genética/genética , Células U937 , Regulação para Cima/genética
18.
J Cancer Res Clin Oncol ; 141(8): 1405-16, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25563492

RESUMO

PURPOSE: Heat shock protein 90 (Hsp90), a potential therapeutic target, has been widely recognized in vitro and in vivo in immunodeficient mice. Here, we aimed to evaluate the role of Hsp90 in an immunocompetent mouse model of esophageal squamous cell cancer (ESCC). METHODS: The carcinogen 4-nitroquinoline 1-oxide (4NQO) was used to induce ESCC in C57BL/6 mice. Cancer progression was analyzed through observation of appearance, hematoxylin-eosin staining, immunohistochemical detection, and terminal dUTP nick-end labeling analysis. RESULTS: 4NQO led to the progressive appearance of preneoplastic and tumoral lesions in the esophagus, with 100 % incidence of ESCC in situ occurring only after 16 weeks of carcinogen exposure. Most of these lesions evolved spontaneously into highly invasive ESCC even after 4NQO withdrawal (weeks 16-22). Interestingly, there was marked upregulation of Hsp90 and its client proteins in tumoral lesions at 22 weeks. Hsp90 inhibition by intraperitoneal injection of SNX-2112 over the following 2 weeks downregulated AKT and cyclin D1 expression, leading to significant reduction in tumor incidence and prevention of ESCC progression. Moreover, SNX-2112 treatment decreased proliferating cell nuclear antigen expression and increased the number of apoptotic cells in ESCC tissues. CONCLUSIONS: Our in vivo findings support the contribution of Hsp90 to ESCC progression, which was achieved by stimulating apoptosis and inhibition of cell proliferation, and provide a strong rationale for further evaluation of Hsp90 inhibitors for treating ESCC.


Assuntos
Carcinoma de Células Escamosas/patologia , Transformação Celular Neoplásica/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Neoplasias Esofágicas/patologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , 4-Nitroquinolina-1-Óxido/farmacologia , Animais , Carcinógenos/farmacologia , Carcinoma de Células Escamosas/metabolismo , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago , Feminino , Camundongos , Camundongos Endogâmicos C57BL
19.
Oncol Lett ; 10(6): 3675-3681, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26788190

RESUMO

Breast metastasis is a rare pattern of distant metastasis from nasopharyngeal carcinoma (NPC) following curative treatment. The present study reported two patients with breast metastasis from NPC and reviewed four such patients reported in the literature, including the analysis of clinical profiles, pathological diagnoses, treatment strategies and outcomes. The breast is a potential metastatic site for patients with NPC following curative treatment; however, thus far, only metachronous breast metastasis has been reported. Infection with Epstein-Barr virus (EBV) was identified in the breast metastasis sites of the two patients investigated in the current study using in situ hybridization for EBV-encoded small RNAs. Patients with breast metastases from NPC consistently and simultaneously develop metastases in other sites. In addition, the two current patients had poor prognoses. Therefore, chemotherapy was the primary treatment strategy administered. A solitary breast metastasis was identified in the male patient. At the most recent follow-up 10 years subsequent to undergoing a Halsted mastectomy, the patient remained alive, however the patient is now lost to follow-up. This case indicates that patients exhibiting NPC with a solitary breast metastasis may still gain long-term survival by undergoing radical mastectomy; therefore, radical mastectomy should be considered in such patients.

20.
Spectrochim Acta A Mol Biomol Spectrosc ; 135: 878-82, 2015 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-25155944

RESUMO

A new complex [Zn(bbb)Cl2]·DMF, where bbb is 2-(2-(1H-benzo[d]imidazol-2-yl)benzyl)-1H-benzo[d]imidazole, was synthesized and characterized by element analysis, (1)H NMR and X-ray single crystal structure analyses. For complex: crystal system, triclinic, space group, P-1, a=9.4661(13), b=10.3534(14), c=13.0025(18)Å, α=73.477(2), ß=80.743(2), γ=88.658(2)°, V=1205.5(3)Å(3), Z=2. In this complex, the Zn(2+) distorted tetrahedron geometry is coordinated by two nitrogen atoms from 2-(2-(1H-benzo[d]imidazol-2-yl)benzyl)-1H-benzo[d]imidazole and two Cl(-). The complex emits yellow green luminescence with the maximal emission peak at 550 nm in DMF solution. The complex exhibits inhibition on the growth of Eca109 cancer cell with IC50 value of 8.9±1.1 µM, which was lower than that of cisplatin (14.3±1.4 µM). This complex has potential application in treatment of esophageal cancer.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Benzimidazóis/síntese química , Benzimidazóis/farmacologia , Imidazóis/síntese química , Imidazóis/farmacologia , Luminescência , Zinco/farmacologia , Antineoplásicos/química , Benzimidazóis/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Humanos , Imidazóis/química , Ligantes , Conformação Molecular , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Termogravimetria
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