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AIM: To investigate the effect of chloride intracellular channel 1 (CLIC1) on the cell proliferation, apoptosis, migration and invasion of gastric cancer cells.METHODS: CLIC1 expression was evaluated in human gastric cancer cell lines SGC-7901 and MGC-803 by real time polymerase chain reaction (RT-PCR). Four segments of small interference RNA (siRNA) targeting CLIC1 mRNA and a no-sense control segment were designed by bioinformatics technology. CLIC1 siRNA was selected using Lipofectamine 2000 and transfected transiently into human gastric cancer SGC-7901 and MGC-803 cells. The transfected efficiency was observed under fluorescence microscope. After transfection, mRNA expression of CLIC1 was detected with RT-PCR and Western blotting was used to detect the protein expression. Proliferation was examined by methyl thiazolyl tetrazolium and apoptosis was detected with flow cytometry. Polycarbonate membrane transwell chamber and Matrigel were used for the detection of the changes of invasion and migration of the two cell lines.RESULTS: In gastric cancer cell lines SGC-7901 and MGC-803, CLIC1 was obviously expressed and CLIC1 siRNA could effectively suppress the expression of CLIC1 protein and mRNA. Proliferation of cells transfected with CLIC1 siRNA3 was enhanced notably, and the highest proliferation rate was 23.3% (P = 0.002) in SGC-7901 and 35.55% (P = 0.001) in MGC-803 cells at 48 h. The G2/M phase proportion increased, while G0/G1 and S phase proportions decreased. The apoptotic rate of the CLIC1 siRNA3 group obviously decreased in both SGC-7901 cells (62.24%, P = 0.000) and MGC-803 cells (52.67%, P = 0.004). Down-regulation of CLIC1 led to the inhibition of invasion and migration by 54.31% (P = 0.000) and 33.62% (P = 0.001) in SGC-7901 and 40.74% (P = 0.000) and 29.26% (P = 0.002) in MGC-803. However, there was no significant difference between the mock group cells and the negative control group cells.CONCLUSION: High CLIC1 expression can efficiently inhibit proliferation and enhance apoptosis, migration and invasion of gastric cancer cells in vitro. CLIC1 might be a promising target for the treatment of gastric cancer.  相似文献   

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目的探讨大黄酸(Rhein)对人胃癌细胞(SGC-7901)增殖、迁移、侵袭、凋亡的影响及其机制。方法通过qRT-PCR检测大黄酸处理后细胞中miR-29c-3p的表达以及miR-29c-3p的转染效率;miR-29c-3p mimics组、NC mimics组、Rhein+miR-29c-3p inhibitor组、Rhein+NC mimics组均使用脂质体转染试剂转染至SGC-7901细胞中,再使用50μM的大黄酸处理48h;CCK-8法检测细胞增殖;Annexin V-FITC/PI和流式细胞术联合检测细胞凋亡;Transwell实验检测细胞迁移和侵袭能力;双荧光素酶报告实验检测细胞荧光活性;Western blot检测FSCN1蛋白表达。结果与NC组相比较,大黄酸处理后可抑制SGC-7901细胞增殖、迁移、侵袭,促进细胞凋亡;过表达miR-29c-3p可抑制细胞增殖、迁移、侵袭,促进细胞凋亡;抑制miR-29c-3p表达可逆转大黄酸对SGC-7901细胞增殖、迁移、侵袭的抑制和细胞凋亡促进作用。miR-29c-3p可靶向作用于FSCN1。结论大黄酸可抑制人胃癌细胞(SGC-7901)增殖、迁移、侵袭,促进细胞凋亡,其机制可能与miR-29c-3p/FSCN1有关,为大黄酸用于治疗胃癌提供一定的科学依据。  相似文献   

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Du  Ying  Xu  Yanjun  Ding  Ling  Yao  Haomi  Yu  Hong  Zhou  Tianhua  Si  Jianmin 《Journal of gastroenterology》2009,44(6):556-561
Purpose  Human microRNA-141 (miR-141), a member of the miR-200 family, has been reported to be associated with various human malignancies. However, it remains unknown whether miR-141 is involved in the pathogenesis of gastric cancer. Therefore, we examined the expression of miR-141 in gastric cancer tissues and the effect of miR-141 overexpression on cancer cell proliferation. Methods  The expression level of miR-141 in 35 pair-matched gastric neoplastic and adjacent non-neoplastic tissues, and in 5 gastric cancer cell lines were examined by quantitative real-time PCR. The growth of MGC-803 cells transfected with miRNA precursor was examined by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazoliumbromide) assay. Results  MiR-141 was significantly down-regulated in 80% (28/35) of primary gastric cancer tissues compared with pair-matched adjacent non-tumor tissues (P < 0.01). The expression of miR-141 was also found to be substantially reduced in several human gastric cancer cell lines such as MGC-803, HGC-27, SGC-7901 and BGC-823 cells. Overexpression of miR-141 with its precursors significantly inhibited the proliferation of gastric cancer cells. Conclusions  These results suggest that miR-141 may be involved in the development of gastric cancer through its inhibitory effect on cell proliferation. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

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BackgroundAtrial fibrillation (AF) is a type of cardiac arrhythmia which is caused by irregular electrical activities in the atria.ObjectiveTo identify serum microRNA (miRNA) biomarkers at three durations (duration since diagnosis of AF) of AF.MethodsThis study included 14 patients with AF and 8 healthy subjects. The blood sample was collected from each patient at baseline (time of diagnosis) and 12-month and 24-month follow-up periods. The serum was used for miRNA sequencing. The differentially expressed miRNAs (DEMs) between the 3 AF and control groups were independently compared. The predicted target genes of DEMs were subjected to functional enrichment and protein-protein interaction network analyses. Additionally, the miRNA-target gene networks were constructed for the 3 AF groups and miRNA time series analysis was performed. The expression of several key miRNAs was verified by real-time quantitative polymerase chain reaction (qRT-PCR).ResultsIn total, 28, 22, and 24 DEMs were identified in the baseline, 12-month, and 24-month groups, respectively. miR-483-5p was the common DEM in the 3 AF groups. In the baseline and 12-month groups, the miR-200b-3p and miR-125b-5p target genes were significantly enriched in the Wnt signaling and several cancer-related pathways, respectively. In the 12-month group, the miR-34a-5p target genes were enriched in the cancer-related pathways. In the miRNA-target gene network, miR-34a-5p regulated the highest number of target genes. The time series analysis revealed that 7 miRNAs, which were downregulated in the control group, were upregulated in the AF groups. The qRT-PCR analysis revealed that the 24-month group exhibited a significant upregulation of miR-483-5p (p < 0.05), whereas the baseline group exhibited significant a downregulation of miR-125b-5p (p < 0.05).ConclusionIn patients with AF, miR-125b-5p and miR-483-5p can be potential biomarkers of the baseline and 24-month periods, respectively.  相似文献   

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Background:Reported studies have shown that expression levels of microRNAs (miRNAs) are related to survival time of patients with heart failure (HF). A systematic review and meta-analysis were conducted to study circulating miRNAs expression and patient outcome.Methods:Meta-analysis estimating expression levels of circulating miRNAs in HF patients from January 2010 until June 30, 2018, through conducting online searches in Pub Med, Cochrane Database of Systematic, EMBASE and Web of Science and reviewed by 2 independent researchers. Using pooled hazard ratio with a 95% confidence interval to assess the correlation between miRNAs expression levels and overall survival.Results:Four relevant articles assessing 19 circulating miRNAs in 867 patients were included. In conclusion, the meta-analysis results suggest that HF patients with low expression of serum miR-1, miR-423-5p, miR-126, miR-21, miR-23, miR-30d, miR-18a-5p, miR-16-5p, miR-18b-5p, miR-27a-3p, miR-26b-5p, miR-30e-5p, miR-106a-5p, miR-233-3P, miR-301a-3p, miR-423-3P, and miR-128 have significantly worse overall survival (P<.05). Among them, miR-18a-5p, miR-18b-5p, miR-30d, miR-30e-5p, and miR-423-5p are strong biomarkers of prognosis in HF.  相似文献   

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目的:研究构建靶向E2F1基因的miR-331真核表达载体,评估其转染人胃癌细胞株SGC-7901细胞后对E2F1基因的干扰效果及其功能,探讨miR-331在胃癌中可能的作用机制.方法:将外源性重组真核表达载体pSuper/miR-331转染到人胃癌细胞株SGC-7901内,经G418筛选并建立高表达miR-331的稳...  相似文献   

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目的探讨胃癌细胞中抑癌基因PTEN5’启动子区CpG岛甲基化状态与其蛋白表达的关系。方法采用甲基化特异性聚合酶链反应(MSP)方法检测不同分化程度的胃癌细胞(HGC-27,MGC-803,BGC-823,SGC-7901)中PTEN基因启动子区域甲基化状态。并通过Western blot法检测该4种细胞中PTEN蛋白的表达。结果除SGC-7901外,其他三种胃癌细胞PTEN基因都有不同程度的甲基化,并随着胃癌细胞分化程度的降低。PTEN启动子区甲基化逐渐增强(P〈0.01);PTEN蛋白表达逐渐减弱(P〈0.01)。PTEN蛋白表达与其启动子区高甲基化之间呈负相关。结论PTEN基因启动子区异常甲基化可能导致该基因失活,使其蛋白表达减少甚至缺失,这可能是导致胃癌发生、发展的重要机制之一。  相似文献   

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AIM: To investigate the tumor-suppressive effect of the phosphatase and tensin homologue deleted from chromosome (PTEN) in human gastric cancer cells that were wild type for PTEN. METHODS: Adenoviruses expressing PTEN or luciferase as a control were introduced into gastric cancer cells. The effect of exogenous PTEN gene on the growth and apoptosis of gastric cancer cells that are wtPTEN were examined in vitro and in vivo. RESULTS: Adenovirus-mediated transfer of PTEN (AdPTEN) suppressed cell growth and induced apoptosis significantly in gastric cancer cells (MGC-803, SGC-7901) carrying wtPTEN in comparison with that in normal gastric epithelial cells (GES-1) carrying wtPTEN. This suppression was induced through downregulation of the Akt/PKB pathway, dephosphorylation of focal adhesion kinase and mitogen-activated protein kinase and cell-cycle arrest at the G2/M phase but not at the G1 phase. Furthermore, treatment of human gastric tumor xenografts (MGC-803, SGC-7901) with Ad-PTEN resulted in a significant (P<0.01) suppression of tumor growth. CONCLUSION: These results indicate a significant tumor-suppressive effect of Ad-PTEN against human gastric cancer cells. Thus, Ad-PTEN may be used as a potential therapeutic strategy for treatment of gastric cancers.  相似文献   

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AIM:To investigate the mechanisms of how cyclooxygenase-2(COX-2)regulates E-cadherin in gastric cancer cells.METHODS:COX-2 expression in human gastric cancer cell lines SGC-7901,BGC-823,MGC-803 and AGS were measured at the mRNA and protein level.COX-2 rich cell line SGC-7901 was chosen for subsequent experiments.siRNA mediated gene knockdown was used to investigate the impact of COX-2 on nuclear factor-κB (NF-κB),Snail,and E-cadherin in gastric cancer cells.Gene expression was determined by Western blot and real-time polymerase chain reaction.To analyze whether NF-κB inhibition could interrupt the modulatory effect of COX-2 or prostaglandin E2(PGE2)on E-cadherin,gastric cancer cells were treated with celecoxib or PGE2,in the presence of NF-κB specific siRNA.RESULTS:Highest expression level of COX-2 was found in SGC-7901 cells,both at mRNA and protein levels.siRNA mediated down-regulation of COX-2 led to a reduced expression of NF-κB and Snail,but an increased expression of E-cadherin in SGC-7901 cells.siRNA mediated down-regulation of NF-κB also led to a reduced expression of E-cadherin and Snail in SGC-7901 cells.However,COX-2 expression did not alter after cells were treated with NF-κB specific siRNA in SGC-7901 cells.Treatment of SGC-7901 cells with celecoxib led to a reduced expression of Snail but an increased expression of E-cadherin.In contrast,treatment of SGC-7901 cells with PGE2 led to an increased Snail and a decreased E-cadherin.However,siRNAmediated knockdown of NF-κB partially abolished the effect of celecoxib and PGE2 on the regulation of E-cadherin and Snail in SGC-7901 cells.CONCLUSION:COX-2 likely functions upstream of NF-κB and regulates the expression of E-cadherin via NF-κB/Snail signaling pathway in gastric cancer cells.  相似文献   

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Background/Aims:

MiR-26a has been identified as a tumor suppressor in various tumors, but the relationship between miR-26a and the sensitivity of gastric cancer to chemotherapies has not been established. The present study was performed to investigate the effect of miR-26a on drug sensitivity in gastric cancer (GC).

Materials and Methods:

The expression level of miRNA-26a in cisplatin-resistant SGC-7901/DDP cells and parent SGC-7901 cells was evaluated by qRT-PCR. The effect of miR-26a on sensitivity of GC cells to cisplatin was assayed using MTS method. The effect of miR-26a on cisplatin-induced apoptosis were determined by Annexin V/propidium iodide (PI) double staining method and flow cytometry. The targets of miR-26a were identified using a luciferase activity assay and miR-26a-mediated target genes expression analysis. Furthermore, the role of the targets neuroblastoma RAS viral (v-ras) oncogene homolog (NRAS) and E2F2 on sensitivity of chemotherapy in GC by MTS and apoptotic cell analysis was assessed.

Results:

We found that miR-26a was downregulated in cisplatin-resistant SGC-7901/DDP cells compared with SGC-7901 cells. Using both gain- and loss-of-function analyses, we further revealed that miR-26a could improve the sensitivity of GC cells to cisplatin. Furthermore, miR-26a has target sites in the 3′-UTR of NRAS and E2F2 by luciferase reporter assay and reduces the expression levels of NRAS and E2F2. In addition, knockdown of NRAS or E2F2 sensitize GC cells to cisplatin.

Conclusion:

Our results suggest that miR-26a can improve the sensitivity of GC cells to cisplatin-based chemotherapies through targeting NRAS and E2F2, and provide the first evidence of the potential utility of miR-26a as a sensitizer in chemotherapy for GC.  相似文献   

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AIM: To investigate the expression of mi R-29 a in rat acute pancreatitis and its functional role in AR42 J cell apoptosis.METHODS: Twelve SD rats were divided into a control group and an acute edematous pancreatitis(AEP) group randomly. AEP was induced by intraperitoneal injection of L-arginine(150 mg/kg) in the AEP group and equal volume of 0.9% Na Cl was injected in the control group. The apoptosis of acinar cells in pancreatic tissue was determined by TUNEL assay. mi RNA chip assay was performed to examine the expression of mi RNAs in two groups. Besides, to further explore the role of mi R-29 a in apoptosis in vitro, recombinant rat TNF-α(50 ng/m L) was administered to treat the rat pancreatic acinar cell line AR42 J for inducing AR42 J cell apoptosis. Quantitative real-time PCR(q RT-PCR) was adopted to measure mi R-29 a expression. Then, mi RNA mimic, mi RNA antisense oligonucleotide(AMO) and control vector were used to transfect AR42 J cells. The expression of mi R-29 a was confirmed by q RT-PCR andthe apoptosis rate of AR42 J cells was detected by flow cytometry analysis. Western blot was used to detect the expression of activated caspase3. Moreover, we used bioinformatics software and luciferase assay to test whether TNFRSF1 A was the target gene of mi R-29 a. After transfection, q RT-PCR and Western blot was used to detect the expression of TNFRSF1 A in AR42 J cells after transfection.RESULTS: The expression of mi R-29 a was much higher in the AEP group compared with the control group as displayed by the mi RNA chip assay. After inducing apoptosis of AR42 J cells in vitro, the expression of mi R-29 a was significantly increased by 1.49 ± 0.04 times in comparison with the control group. As revealed by q RT-PCR assay, the expression of mi R-29 a was 2.68 ± 0.56 times higher in the mi R-29 a mimic group relative to the control vector group, accompanied with an obviously increased acinar cell apoptosis rate(42.83 ± 1.25 vs 24.97 ± 0.15, P 0.05). Moreover, the expression of mi R-29 a in the mi RNA AMO group was 0.46 ± 0.05 times lower than the control vector group, and the cell apoptosis rate was much lower accordingly(17.27 ± 1.36 vs 24.97 ± 0.15, P 0.05). The results of bioinformatics software and luciferase assay showed that TNFRSF1 A might be a target gene of mi R-29 a. TNFRSF1 A expression was up-regulated in the mi R-29 a mimic group, while the mi R-29 a AMO group showed the reverse trend.CONCLUSION: mi R-29 a might promote the apoptosis of AR42 J cells via up-regulating the expression of its target gene TNFRSF1 A.  相似文献   

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BACKGROUND Gastric cancer(GC)is a prevalent malignancy,leading to a high incidence of cancer-associated death.Cisplatin(DDP)-based chemotherapy is the principal therapy for clinical GC treatment,but DDP resistance is a severe clinical challenge and the mechanism remains poorly understood.Circular RNAs(circRNAs)have been identified to play crucial roles in modulating the chemoresistance of gastric cancer cells.AIM To explore the effect of circVAPA on chemotherapy resistance during GC progression.METHODS The effect of circVAPA on GC progression and chemotherapy resistance was analyzed by MTT assay,colony formation assay,Transwell assay,wound healing assay,and flow cytometry analysis in GC cells and DDP resistant GC cell lines,and tumorigenicity analysis in nude mice in vivo.The mechanism was investigated by luciferase reporter assay,quantitative real-time PCR,and Western blot analysis.RESULTS CircVAPA expression was up-regulated in clinical GC tissues compared with normal samples.CircVAPA depletion inhibited proliferation,migration,and invasion and increased apoptosis of GC cells.The expression of circVAPA,STAT3,and STAT3 downstream genes was elevated in DDP resistant SGC7901/DDP cell lines.CircVAPA knockdown attenuated the DDP resistance of GC cells.Mechanically,circVAPA was able to sponge miR-125b-5p,and miR-125b-5p could target STAT3 in the GC cells.MiR-125b-5p inhibitor reversed circVAPA depletion-enhanced inhibitory effect of DDP on GC cells,and STAT3 knockdown blocked circVAPA overexpression-induced proliferation of DDPtreated SGC7901/DDP cells.The depletion of STAT3 and miR-125b-5p inhibitor reversed circVAPA depletion-induced GC cell apoptosis.Functionally,circVAPA contributed to the tumor growth of SGC7901/DDP cells in vivo.CONCLUSION CircVAPA promotes chemotherapy resistance and malignant progression in GC by miR-125b-5p/STAT3 signaling.Our findings present novel insights into the mechanism by which circVAPA regulates chemotherapy resistance of GC cells.CircVAPA and miR-125b-5p may be considered as the potential targets for GC therapy.  相似文献   

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AIM: To develop orthotopic gastric cancer mouse models from different cell lines and characterize the tumor features to assist further in preclinical trials and clinical treatment strategies.METHODS: Human gastric cancer SGC-7901 and BGC-823 cell suspensions were injected subcutaneously into nude mice to develop solid tumors, and tumor tissue pieces were then implanted under the serous coat of the stomach. An autopsy was performed on all animals of the SGC-7901 and BGC-823 models to observe the primary tumor growth and metastases using pathological and immunohistochemical methods.RESULTS: Both models showed large tumors in situ resulting in pressure and infiltration of the adjacent organs. The gastric cavity became smaller, along with stenosis of the cardia or pylorus. There were biological and statistical differences between the two models. The metastasis rate in involved organs (lymph nodes, kidney, spleen, testis) was significantly higher in the BGC-823 model compared to the SGC-7901 model (P < 0.05 or P < 0.01). The median survival of the BGC-823 model was shorter than that of SGC-7901 (23 d vs 84 d, P < 0.05). Histopathologically, the primary tumor and metastatic lesions of the two models showed obvious atypia and mucus in the cytoplasm. Compared with the SGC-7901 model, BGC-823 appeared more poorly differentiated (absence of adenoid structure), had a smaller volume, and richer capillary structure. Immunohistochemical staining revealed cytokeratin 20 and epithelial membrane antigen expression was positive in the SGC-7901 tumors, while negative in BGC-823 ones.CONCLUSION: Models using the SGC-7901 and BGC-823 cell lines were established which could function in gastric cancer research on carcinogenesis mechanism and drug discovery. The two models showed different tumor behavior and the latter was more malignant than the former.  相似文献   

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Background

Circulating microRNA (miRNA) has attractive interests as a non-invasive biomarker of physiological and pathological conditions. Our study aimed to investigate the potential effects of chronic benzene poisoning (CBP) and benzene exposure on miRNA expression, and identify CBP-related miRNAs.

Methods

In the discovery stage, we used a microarray assay to detect the miRNA expression profiles among pooled plasma samples from ten CBP patients, ten healthy benzene-exposed individuals and ten non-benzene exposed individuals. Subsequently, we conducted an expanded validation of six candidate miRNAs in 27 CBP patients- low blood counts, 54 healthy benzene-exposed individuals and 54 non-exposed individuals. Moreover, we predicted the biological functions of putative target genes using a Gene Ontology (GO) function enrichment analysis and KEGG pathway analysis.

Results

In the discovery stage, compared with non-exposures, 36 and 12 miRNAs demonstrated at least a 1.0-fold differential expression in the CBP patients and the benzene exposures, respectively. And compared with benzene exposures, 58 miRNAs demonstrated at least a 1.0-fold differential expression in the CBP patients. In the expanded validation stage, compared with non-exposures as well as exposures, miR-24-3p and miR-221-3p were significantly up-regulated (1.99- and 2.06-fold for miR-24-3p, 2.19- and 3.93-fold for miR-221-3p, P<0.01) while miR-122-5p and miR-638 were significantly down-regulated (−3.45- and −2.60-fold for miR-122-5p, −1.82- and −3.20-fold for miR-638, P<0.001) in the CBP patients; compared with non-exposures, the plasma level of miR-638 was significantly up-regulated (1.38-fold, P<0.01) while the plasma levels miR-122-5p and miR-221-3p were significantly down-regulated (−0.85- and −1.74-fold, P<0.01) in the exposures, which were consistent with the results of microarray analysis.

Conclusions

The four indicated plasma miRNAs may be biomarkers of indicating responses to benzene exposure. Further studies are warranted to verify our findings with a large sample and to confirm the underlying mechanisms.  相似文献   

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目的:研究非甾体类抗炎药(NSAID)塞来昔布对胃癌细胞MGC-803的抑制作用和对RECK、MMP-2、MMP-9基因表达的影响,以探讨塞来昔布的抗肿瘤机制.方法:培养胃癌MGC-803细胞,实验用不同浓度的塞来昔布(25、50、100μg/L)分别处理MGC-803细胞不同时间(12、24 h、48 h),无血清培养基饥饿24 h达同步化后,MTT(噻唑蓝比色法)观察MGC-803细胞增殖;RT-PCR法检测细胞周期调控因子MMP-9、MMP-2、RECK mRNA的表达;Western blot法检测MMP-9、MMP-2、RECK mRNA蛋白的表达.结果:M T T法显示塞来昔布能抑制胃癌MGC-803细胞增殖,作用12 h时,随着塞来昔布处理浓度的增高,其抑制作用不明显,组间比较差异不显著(P>0.05),在作用24、48 h时呈浓度依赖性(25-100μg/L),在25、50、100μg/L作用浓度呈时间依赖性(24-48 h).塞来昔布在100μg/L浓度作用细胞48 h时抑制.RT-PCR法检测结果显示,在12 h的作用时间点,随着塞来昔布处理浓度的增高,RECK基因及MMP-2、MMP-9 mRNA变化不是很明显,组间比较无显著差异(P>0.05),在12 h后,塞来昔布能增加胃癌细胞RECK mRNA和蛋白表达,作用呈浓度(25-100μg/L)和时间依赖性(24-48h),MMP-2、MMP-9表达则下降.Western blot法检测结果显示,作用12 h时,随着塞来昔布处理浓度的增高,其RECK蛋白及MMP-2,MMP-9蛋白改变不明显,组间比较差异不显著(P>0.05),在12 h以后,塞来昔布能增加RECKmRNA和蛋白表达并减少MMP-2、MMP-9表达,且作用呈浓度依赖性和时间依赖.结论:塞来昔布可抑制人胃癌MGC-803细胞增殖与转移;其可能是通过上调RECK基因,进而下调MMP-2、MMP-9来抑制胃癌细胞MGC-803的增殖与转移.  相似文献   

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