RESUMO
Vasculogenic mimicry (VM) gives rise to tumor neovascularization that is critical for tumor growth and metastasis. Long non-coding RNAs (lncRNAs) have been implicated in diverse and fundamental biological processes. LINC00312 is associated with lung adenocarcinoma. In this study, we found that LINC00312 induced migration, invasion and VM of lung cancer cells by direct binding to the transcription factor Y-Box Binding Protein 1 (YBX1). Moreover, we demonstrated that YBX1 is associated with different fragments within 0-2410 nt 5'region of LINC00312. In addition, LINC00312 is associated with VM in 124 lung adenocarcinoma clinical specimens. The results suggest that LINC00312 is a promising therapeutic and diagnostic target for lung adenocarcinoma.
Assuntos
Adenocarcinoma de Pulmão/irrigação sanguínea , Adenocarcinoma de Pulmão/genética , Neoplasias Pulmonares/irrigação sanguínea , Neoplasias Pulmonares/genética , RNA Longo não Codificante/genética , Proteína 1 de Ligação a Y-Box/genética , Adenocarcinoma de Pulmão/patologia , Diferenciação Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Humanos , Neoplasias Pulmonares/patologia , Neovascularização Patológica/genética , Neovascularização Patológica/patologiaRESUMO
Lung cancer is the leading cause of cancer-related mortality worldwide. Approximately 80% of lung cancer cases are non-small cell lung carcinoma (NSCLC). However current diagnostic and therapeutic modalities against NSCLC are ineffective due to incomplete understanding of molecular pathogenesis of NSCLC. Emerging evidence shows that long non-coding RNAs (lncRNAs) can function as biomarkers for diagnosis and prognosis. LncRNAs can control transcription, translation, and protein function via diverse mechanisms although they lack the protein coding potential. LncRNAs have attracted intense investigations on their roles in cancer. Mounting evidence indicates that lncRNAs are promising biomarkers in diagnosis and prognosis for NSCLC, especially their presence in body fluids. Herein we will review recent advances in the research that explores the diagnostic and prognostic potentials of lncRNAs in NSCLC. We will also discuss emerging evidence that suggested lncRNAs as therapeutic targets in NSCLC.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Neoplasias Pulmonares/diagnóstico , RNA Longo não Codificante/sangue , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Prognóstico , RNA Longo não Codificante/metabolismo , Escarro/metabolismoRESUMO
OBJECTIVE: To explore two transcript variants expression of long noncoding RNA C6orf176 in non-small cell lung cancer (NSCLC) and the clinical pathological significance. â© METHODS: The expressions of transcript variant 1 (TV1) and transcript variant 2 (TV2) of long noncoding RNA C6orf176 in 57 NSCLC and adjacent cancerous tissues were examined by qPCR with ß-actin as internal control.â© RESULTS: Based on the results of qPCR, for C6orf176-TV1, 42 cases were down-regulated and 15 cases were up-regulated. The C6orf176-TV1 level was correlated to the grade of differentiation (P<0.05) but it was not correlated with gender, age, smoking history, tumor type and TNM stage. The expression of C6orf176-TV1 had a potential value in diagnosis of NSCLC by receiver operator characteristic (ROC) curve. Area under curve (AUC) of ROC curve was 0.708 (95% CI 0.615 to 0. 802). The sensitivity and specificity were 51% and 88%, respectively. For C6orf176-TV2, 39 cases were down-regulated and 18 cases were up-regulated. The C6orf176-TV2 level was correlated with the grade of differentiation (P<0.05) but it was not correlated with gender, age, tumor size, smoking history and TNM stage. C6orf176-TV2 level had value in diagnosis of NSCLC by ROC curve. AUC of ROC curve was 0.64 (95% CI 0.531 to 0.749). The sensitivity and specificity were 49% and 75%, respectively. Of the 57 specimens, 53 cases were simultaneous up or down-regulation of C6orf176-TV1 and C6orf176-TV2. The correlation coefficient was 0.99.â© CONCLUSION: The expression of C6orf176-TV1 or C6orf176-TV2 is down-regulated in NSCLC and it is correlated with the grade of differentiation. It may act as a diagnosis indicator for NSCLC patients.
Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Actinas , Área Sob a Curva , Diferenciação Celular , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , RNA Longo não Codificante , Curva ROC , Reação em Cadeia da Polimerase em Tempo Real , Fumar , Transcrição Gênica , Regulação para CimaRESUMO
Treatment of carcinoma commonly fails due to chemoresistance. Studies have shown that endothelial cells acquire resistance via the tumor microenvironment. Microvesicle (MV) shedding from the cell membrane to the microenvironment plays an important role in communication between cells. The aim of the present study was to determine whether MCF-7 adriamycin-resistant cells (MCF-7/ADM) shed MVs that alter the characteristics of human microvessel endothelial cells (HMECs). MVs from tumor cells transferred a Ca(2+)-permeable channel TrpC5 to HMECs, inducing the expression of P-glycoprotein (P-gp) by activation of the transcription factor NFATc3 (nuclear factor of activated T cells isoform c3). Expression of the mdr1 gene was blocked by the TrpC5-blocking antibody T5E3, and the production of P-gp in HMECs was reduced by blockade of TrpC5. Thus, we postulate that endothelial cells acquire the resistant protein upon exposure to TrpC5-containg MVs in the microenvironment, and express P-gp in the TrpC5-NFATc3 signal pathway.
Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Fatores de Transcrição NFATC/metabolismo , Canais de Cátion TRPC/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Animais , Antineoplásicos/farmacologia , Neoplasias da Mama/irrigação sanguínea , Comunicação Celular , Micropartículas Derivadas de Células/metabolismo , Células Cultivadas , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Células Endoteliais/metabolismo , Feminino , Expressão Gênica , Xenoenxertos , Humanos , Células MCF-7 , Camundongos , Camundongos Nus , Transdução de Sinais , Microambiente TumoralRESUMO
Objective: Whether neutrophil-lymphocyte ratio (NLR) is an applicative predictor of poor prognosis in patients with hepatocellular carcinoma (HCC) remains controversial. In response to the current conflicting data, this meta-analysis was conducted to gain a comprehensive and systematic understanding of prognostic value of NLR in HCC. Methods: Several English databases, including PubMed, EMBASE, and the Cochrane Library, with an update date of February 25, 2023, were systematically searched. We set the inclusion criteria to include randomized controlled trial (RCT) studies that reported the prognostic value of serum NLR levels in patients with HCC receiving treatment. Both the combined ratio (OR) and the diagnosis ratio (DOR) were used to assess the prognostic performance of NLR. Additionally, we completed the risk of bias assessment by Cochrane Risk of Bias Assessment Tool. Results: This meta-analysis ultimately included 16 studies with a total of 4654 patients with HCC. The results showed that high baseline NLR was significantly associated with poor prognosis or recurrence of HCC. The sensitivity of 0.67 (95% confidence interval [CI]. 0.59-0.73); specificity of 0.723 (95% CI: 0.64-0.78) and DOR of 5.0 (95% CI: 4.0-7.0) were pooled estimated from patient-based analyses. Subsequently, the combined positive likelihood ratio (PLR) and negative likelihood ratio (NLHR) were calculated with the results of 2.4 (95% CI: 1.9-3.0) and 0.46 (95% CI: 0.39-0.56), respectively. In addition, area under the curve (AUC) of the summary receiver operating characteristic (SROC) reflecting prognostic accuracy was calculated to be 0.75 (95% CI: 0.71-0.78). The results of subgroup analysis suggested that high NLR was an effective predictive factor of poor prognosis in HCC in mainland China as well as in the northern region. Conclusion: Our findings suggest that high baseline NLR is an excellent predictor of poor prognosis or relapse in patients with HCC, especially those from high-incidence East Asian populations. Systematic review registration: https://www.crd.york.ac.uk/prospero/#recordDetails, identifier CRD42023440640.
Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neutrófilos/patologia , Neoplasias Hepáticas/patologia , Recidiva Local de Neoplasia , Linfócitos/patologia , PrognósticoRESUMO
BACKGROUND: As a subclass of endogenous stable noncoding RNAs, circular RNAs are beginning to be appreciated for their potential as tumor therapeutics. However, the functions and mechanisms by which circRNAs exert protective functions in non-small cell lung cancer (NSCLC) remain largely elusive. METHODS: The prognostic role of circGUCY1A2 was explored in lung adenocarcinoma specimens. The overexpressed and knockdown plasmids were used to evaluate the effect of circGUCY1A2 on NSCLC cell proliferation and apoptosis efficacy. Luciferase reporter system is used to prove that circGUCY1A2 could bind to miRNA. Chip-PCR was used to prove that circGUCY1A2 could be initiated by transcription factors ARNTL. Subcutaneous tumorigenicity grafts models were established to validate findings in vivo. RESULTS: The expression of circGUCY1A2 were significantly reduced (P < 0.001) and negatively correlated with tumor size (P < 0.05) in non-small cell lung cancer (NSCLC). CircGUCY1A2 upregulation promoted apoptosis and inhibits cell proliferation and growth of subcutaneous tumorigenicity grafts in nude mice (P < 0.01). In addition, intra-tumor injection of pLCDH-circGUCY1A2 inhibited tumor growth in patient-derived NSCLC xenograft models (PDX). Mechanism studies showed that circGUCY1A2 could act as a sponge to competitively bind miR-200c-3p, promote PTEN expression, and thereby inhibit PI3K/AKT pathway. In addition, we found that the circadian gene ARNTL, which was reduced in NSCLC and prolonged the overall survival of patients, could bind to the promoter of circGUCY1A2, thereby increasing its expression. CONCLUSIONS: This study is an original demonstration that ARNTL can inhibit the development of lung adenocarcinoma through the circGUCY1A2/miR-200c-3p/PTEN axis, and this finding provides potential targets and therapeutic approaches for the treatment of lung adenocarcinoma.
Assuntos
Fatores de Transcrição ARNTL , Adenocarcinoma de Pulmão , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , RNA Circular , Animais , Humanos , Camundongos , Carcinoma Pulmonar de Células não Pequenas/genética , Modelos Animais de Doenças , Neoplasias Pulmonares/genética , Camundongos Nus , Fosfatidilinositol 3-Quinases , PTEN Fosfo-Hidrolase/genética , RNA Circular/genéticaRESUMO
Disproportionately high incidence and mortality of respiratory infection such as influenza A virus (IAV) and SARS-CoV-2 have been evidenced in the elderly, but the role and the mechanism of age-associated immune deregulation in disease exacerbation are not well defined. Using a late generation of mice deficient in telomerase RNA (Terc-/- ), we herein demonstrated that aged mice were exquisitely susceptible to respiratory viral infection, with excessive inflammation and increased mortality. Furthermore, we identified the cGAS/STING pathway, which was essentially induced by the leaked mitochondrial DNA, as a biologically relevant mechanism contributing to exaggerated inflammation in Terc-/- mice following viral infection. Innate immune cells, mainly, macrophages with shortened telomeres, exhibited hallmarks of cellular senescence, mitochondrial distress, and aberrant activation of STING and NLRP3 inflammasome pathways, which predisposed mice to severe viral pneumonia during commonly mild infections. Application of STING inhibitor and, more importantly, senolytic agent, reduced the burden of stressed macrophages, improved mitochondrial integrity, and suppressed STING activation, thereby conferring the protection for Terc-/- mice against respiratory infection. Together, the findings expand our understanding of innate immune senescence and reveal the potential of the senolytics as a promising treatment to alleviate the symptom of viral pneumonia, particularly for the older population.
Assuntos
COVID-19 , Imunidade Inata , Animais , Inflamação , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , SARS-CoV-2 , Transdução de Sinais , Telômero/metabolismoRESUMO
Nanosecond pulsed electric field (nsPEF) is a novel ablation technique that is based on high-intensity electric voltage to achieve tumour-killing effect in the target region, and increasingly considered for treating tumours of the liver, kidneys and other organs with rich blood supply. This study aims to observe effect of nsPFE treatment on serum metabolites and gut microbiota. The serum and faecal specimens of the pigs were collected pre- and post-treatment. The gut microbiota of pigs was sequenced by Illumina Miseq platform for analysing the diversity and alterations of gut microbiota. Liquid chromatography-mass spectrometry (LC-MS)-based metabonomic analysis and Pearson coefficient method were also used to construct the interaction system of different metabolites, metabolic pathways and flora. A total of 1,477 differential metabolites from the serum were identified by four cross-comparisons of different post-operative groups with the control group. In addition, an average of 636 OTUs per sample was detected. Correlation analysis also revealed the strong correlation between intestinal bacteria and differential metabolites. The nsPEF ablation of the liver results in a degree of liver damage that affects various metabolic pathways, mainly lipid metabolism, as well as gut microbiota. In conclusion, our study provided a good point for the safety and feasibility of applying nsPEF on liver through the integrated analysis of metabolomics and microbiomes, which is beneficial for the improvement of nsPEF in clinical use.
RESUMO
Dendritic cells (DCs) are recognized as a key orchestrator of immune response and homeostasis, deregulation of which may lead to autoimmunity such as experimental autoimmune encephalomyelitis (EAE). Herein we show that the phosphatase PP2Cδ played a pivotal role in regulating DC activation and function, as PP2Cδ ablation caused aberrant maturation, activation, and Th1/Th17-priming of DCs, and hence induced onset of exacerbated EAE. Mechanistically, PP2Cδ restrained the expression of the essential subunit of mTORC2, Rictor, primarily through de-phosphorylating and proteasomal degradation of the methyltransferase NSD2 via CRL4DCAF2 E3 ligase. Loss of PP2Cδ in DCs accordingly sustained activation of the Rictor/mTORC2 pathway and boosted glycolytic and mitochondrial metabolism. Consequently, ATP-citrate lyse (ACLY) was increasingly activated and catalyzed acetyl-CoA for expression of the genes compatible with hyperactivated DCs under PP2Cδ deletion. Collectively, our findings demonstrate that PP2Cδ has an essential role in controlling DCs activation and function, which is critical for prevention of autoimmunity.
Assuntos
ATP Citrato (pro-S)-Liase/imunologia , Diferenciação Celular/imunologia , Células Dendríticas/imunologia , Histona-Lisina N-Metiltransferase/imunologia , Alvo Mecanístico do Complexo 2 de Rapamicina/imunologia , Proteína Fosfatase 2C/imunologia , Transdução de Sinais/imunologia , ATP Citrato (pro-S)-Liase/genética , Animais , Diferenciação Celular/genética , Feminino , Histona-Lisina N-Metiltransferase/genética , Alvo Mecanístico do Complexo 2 de Rapamicina/genética , Camundongos , Camundongos Knockout , Proteína Fosfatase 2C/genética , Transdução de Sinais/genéticaRESUMO
Lung cancer is the leading cause of cancer-related mortality worldwide. Recently, accumulating data indicate that long noncoding RNAs (LncRNAs) function as novel crucial regulators of diverse biological processes, including proliferation and metastasis, in tumorigenesis. Lnc NONHSAT081507.1 (LINC81507) is associated with lung adenocarcinoma. However, its pathological role in non-small cell lung cancer (NSCLC) remains unknown. In our study we investigated the role of LINC81507 in NSCLC. The expression of LINC81507 was analyzed in 105 paired NSCLC tumor specimens and paired adjacent non-tumorous tissues from NSCLC patients by real-time quantitative PCR (RT-qPCR). Gain- and loss-of-function experiments were conducted to investigate the functions of LINC81507, miR-199b-5p and CAV1. Reduced expression of LINC81507 resulted in cell growth, proliferation, migration and epithelial-mesenchymal transition (EMT) in NSCLC cells, whereas ectopic overexpression of LINC81507 resulted in the opposite effects both in vitro and in vivo. Nuclear and Cytoplasmic fractionation assays showed LINC81507 mainly resided in cytoplasm. Bioinformatics analysis and dual-luciferase assays revealed that miR-199b-5p was a direct target of LINC81507 through binding Ago2. Mechanistic analysis demonstrated that miR-199b-5p specifically targeted the Caveolin1 (CAV1) gene, and LINC81507 inactivated the STAT3 pathway in a CAV1-dependent manner. Taken together, LINC81507 is decreased in NSCLC and functions as a sponge to miR-199b-5p to regulate CAV1/STAT3 pathway, which suggests that LINC81507 serve as a tumor suppressor and potential therapeutic target and biomarker for metastasis and prognosis in NSCLC.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/secundário , Caveolina 1/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Fator de Transcrição STAT3/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma/secundário , Animais , Proteínas Argonautas/metabolismo , Carcinogênese/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/secundário , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Pessoa de Meia-Idade , Prognóstico , RNA Longo não Codificante/genética , Fator de Transcrição STAT3/genética , Transplante HeterólogoRESUMO
Circular RNAs (circRNAs) are a class of endogendous RNAs that form a covalently closed continuous loop and exist extensively in mammalian cells. Majority of circRNAs are conserved across species and often show tissue/developmental stage-specific expression. CircRNAs were first thought to be the result of splicing error; however, subsequent research shows that circRNAs can function as microRNA (miRNA) sponges and regulate splicing and transcription. Emerging evidence shows that circRNAs possess closely associated with human diseases, especially cancers, and may serve as better biomarkers. After miRNA and long noncoding RNA (lncRNA), circRNAs are becoming a new hotspot in the field of RNA of cancer. Here, we review biogenesis and metabolism of circRNAs, their functions, and potential roles in cancer.
Assuntos
Neoplasias/genética , RNA/metabolismo , Humanos , RNA/biossíntese , RNA/fisiologia , Splicing de RNA , RNA Circular , Transcrição GênicaRESUMO
LncRNAs have emerged as a novel class of critical regulators of cancer. We aimed to construct a landscape of lncRNAs and their potential target genes in lung adenocarcinoma. Genome-wide expression of lncRNAs and mRNAs was determined using microarray. qRT-PCR was performed to validate the expression of the selected lncRNAs in a cohort of 42 tumor tissues and adjacent normal tissues. R and Bioconductor were used for data analysis. A total of 3045 lncRNAs were differentially expressed between the paired tumor and normal tissues (1048 up and 1997 down). Meanwhile, our data showed that the expression NONHSAT077036 was associated with N classification and clinical stage. Further, we analyzed the potential co-regulatory relationship between the lncRNAs and their potential target genes using the 'cis' and 'trans' models. In the 25 related transcription factors (TFs), our analysis of The Cancer Genome Atlas database (TCGA) found that patients with lower expression of POU2F2 and higher expression of TRIM28 had a shorter overall survival time. The POU2F2 and TRIM28 co-expressed lncRNA landscape characterized here may shed light into normal biology and lung adenocarcinoma pathogenesis, and be valuable for discovery of biomarkers.
Assuntos
Adenocarcinoma de Pulmão , Biomarcadores Tumorais , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Neoplasias Pulmonares , RNA Longo não Codificante , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Adulto , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Bases de Dados de Ácidos Nucleicos , Feminino , Estudo de Associação Genômica Ampla , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , RNA Longo não Codificante/biossíntese , RNA Longo não Codificante/genéticaRESUMO
Platelet-derived growth factor receptor (PDGFR)-ß is an important tyrosine kinase and its downregulation has been reported to alter the radiosensitivity of glioma cells, although the underlying mechanism is unclear. In order to investigate the effect of PDGFR-ß on the radiosensitivity of glioblastoma, the present study transfected C6 glioma cells with a PDGFR-ß-specific small interfering (si)RNA expression plasmid, and downregulation of the expression of PDGFR-ß in C6 glioma cells was confirmed by western blotting and immunohistochemical analysis. Clone formation assays and xenograft growth curves demonstrated that PDGFR-ß-siRNA enhanced the radiosensitivity of C6 glioma cells in vitro and in vivo. Furthermore, MTT and xenograft growth curves demonstrated that PDGFR-ß-siRNA inhibited the proliferation of C6 glioma cells in vitro and in vivo, and terminal deoxynucleotidyl transferase dUTP nick end-labeling and immunohistochemical analyses demonstrated that PDGFR-ß-siRNA induced apoptosis and inhibited the expression of Ki-67, cyclin B1 and vascular endothelial growth factor in C6 glioma cell xenografts. Taken together, these results suggested that PDGFR-ß may be used as a target for the radiosensitization of glioblastoma.
RESUMO
The Fip1-like1 (FIP1L1)-platelet-derived growth factor receptor alpha (PDGFRA) (F/P) oncogene can cause chronic eosinophilic leukemia (CEL), but requires IL-5 cytokine participation. In this study, we investigate the mechanism of F/P in collaboration with IL-5 in CEL. The results showed that Lyn, a key effector in the IL-5-motivated eosinophil production, is extensively activated in F/P-positive CEL cells. Lyn can associate and phosphorylate IL-5 receptor α (IL-5RA) in F/P-positive cells. Moreover, the activation of Lyn and IL-5R kinase were strengthened when the cells were stimulated by IL-5. Lyn inhibition in F/P-positive CEL cells attenuated cellular proliferation, induced apoptosis, and blocked cell migration and major basic protein (MBP) release. We identified the FIP1L1-PDGFRA/JAK2/Lyn/Akt complex in the F/P-expressing cells which can be disrupted by dual inhibition of JAK2 and Lyn, repressing cell proliferation in both EOL-1(F/P-positive human eosinophilic cell line) and imatinib-resistance (IR) cells. Altogether, our data demonstrate that Lyn is a vital downstream kinase activated by F/P converged with IL-5 signals in CEL cells. Lyn activate and expand IL-5RA intracellular signaling through FIP1L1-PDGFRA/JAK2/Lyn/Akt network complex, provoking eosinophils proliferation and exaggerated activation manifested as CEL.
RESUMO
The overexpression of P-glycoprotein (P-gp) causes resistance to chemotherapy in human ovarian cancer. However, the underlying mechanism remains unclear. In the present study, we showed that, at membrane-bound protein level, P-gp was 'shared' between human ovarian cancer cells by the intercellular transfer of microvesicles (MVs). Paclitaxel-resistant human ovarian cancer cells (A2780/PTX) readily formed and released P-gp-containing MVs into the extracellular space compared with the wild-type parental line (A2780/WT). Shedding MVs bound to the chemosensitive A2780/WT cells in a time- and dose-dependent manner, transferring P-gp via the microenvironment. MV-mediated transfer of P-gp led to redistribution of the chemotherapeutic drug adriamycin in recipient cells (A2780/WT), which displayed 5- and 5-fold higher resistance to adriamycin and paclitaxel, respectively. Thus, these findings demonstrate a new mechanism of drug-resistance acquisition via MVs.
Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Neoplasias Ovarianas/patologia , Paclitaxel/farmacologia , Linhagem Celular Tumoral , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Feminino , Humanos , Transporte Proteico/efeitos dos fármacosRESUMO
The fluorescence emitted by the functionalized ZnS nanocrystal at 440 nm could be efficiently enhanced or quenched when various peptides were added. The mechanism of the fluorescence enchancement and quenching of ZnS nanocrystals was discussed. The binding constant and numbers of binding sites was obtained from the Scatchard plot. The change of fluorescence intensity was in proportion to the concentration of peptides. The limits of detection were in range of 0.011-0.028 microg mL(-1). Application results to synthetic samples showed simplicity, rapidity, high sensitivity and satisfactory reproducibility of the presented method. Measurements of real samples also give satisfactory results which were in good agreement with those obtained using high performance liquid chromatograph (HPLC) and liquid chromatograph-mass spectrograph (LC-MS) methods.
Assuntos
Nanopartículas , Peptídeos/análise , Espectrometria de Fluorescência/métodos , Sulfetos/química , Compostos de Zinco/química , Calibragem , Coloides , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Resonance light scattering (RLS) of the functionalized ZnS nanocrystals-peptides system and its analytical application have been studied. The RLS intensity can be efficiently enhanced when various peptides were added. The mechanism of the RLS enhancement of ZnS nanocrystals was discussed. The change of RLS intensity was in proportion to the concentration of peptides. The limits of detection were in range of 2.8-5.7 ng mL(-1). Application results to synthetic samples showed simplicity, rapidity, high sensitivity and satisfactory reproducibility of the presented method. Measurements of real samples also give satisfactory results which were in good agreement with those obtained using high performance liquid chromatography (HPLC) and liquid chromatography-mass spectrography (LC-MS) methods.