Initial study on apoptosis in HepG-2 Human heptocarcinoma cell line by CSS

Objective To discuss on mechanism of the killing and apoptosis inducing effect induced by total alkaloid in the CSS(Capparis spinosa L.saponin,CSS)on human hepatocarcinoma cell Line HepG-2.Methods The killing effect of the CSS on human hepatocarcinoma cell Line HepG-2 was observed by MTT method.Morphological observation of the HepG-2 cells was completed by fluorescence microscope.This test was signed to observe the changes of the cell cycle of HepG-2 cells affected by the CSS by PI single-staining,and to observe if there were typical apoptosis peaks.The apoptosis inducing effect and changing of mitochondria membrane potential of the CSS on the HepG-2 cells were studied by flow cytometry.The effect of intracellular Ca2+ level of CSS on the HepG-2 cells was measured by laser confocal microscope.Results CSS has growth inhibiting on the HepG-2 and seems to be enhanced with the increasing concentration of CSS,and its IC50 value was 46.16 μg·mL-1.The HepG-2 cells are characteristic apoptosis morphologic changed,and the apoptosis percentage is increased to 66.652% in the 50 μg·mL-1 dosage group.The cells cycle has been changed obviously that the progresses of cells cycle of G1 period and G2 period in high dosage group have been blocked,and the cellular proportion in G2 period is decreased by the function of CSS for 24 h.The mitochondria membrane potential of HepG-2 cells induced by CSS is decreased in various degrees.In addition,the intracellular Ca2+ level is increased by the function of CSS in the middle and high dose groups.Conclusions The CSS has obviously killing and apoptosis inducing effect on human hepatocarcinoma cell Line HepG-2 by the mechanism of decreasing the mitochondria membrane potential and increasing the intracellular Ca2+ level.

Effect of a nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester on invasion of human colorectal cancer cell line SL-174T

AIML To investigate the effect and mechanism of action of the nitric oxide synthase （NOS） inhibitor NG-nitro-L-arginine methyl ester （L-NAME） on invasion and metastasis of human colorectal cancer cell line SL-174T. METHODS： Human colorectal cancer cel4 line SL-174T was cultured and treated separately with four different dosages of L-NAME for 72 h, Nitric oxide （NO） production was measured with Griess reagent, The effect of L-NAME on invasion and migration of SL-174T cells were evaluated by using Transwell chambers attached with polycarbonate filters and reconstituted basement membrane （Matrigel）, RT-PCR was performed to determine the mRNA levels of matrix metalloproteinase-2 （MMP-2） and tissue inhibitor metalloproteinase-2 （TIMP-2）,RESULTS： L-NAME could significantly inhibit NO production of SL-174T in a dose-dependent manner. After being treated for 72 h with 0.2, 0.4, 0.8, and 1.0 mmol/L L- NAME, respectively, the ability of the L-NAME treated SL- 174T cells to invade the reconstituted basement membrane decreased significantly （t = 8.056, P〈0.05; t= 14.467, P〈0.01; t= 27.785, P〈0.01; and t= 29.405, P〈0.01, respectively） and the inhibition rates were 10.29%, 19.62%, 34.08%, and 42.23%, respectively. Moreover, L-NAME could inhibit migration of SL-174T cells, and the inhibition rates were 20.76%, 24.95%, 39.43%, and 46. 85% for L-NAME at 0.2, 0.4, 0.8, and 1.0 mmol/L, respectively （t = 15.116, P〈0.01）. In addition, after treatment with L-NAME, expression of MMP-2 mRNA was significantly decreased （t = 71.238, P〈0.01） and that of TIMP-2 mRNA was markedly increased （t = -13.020, P〈0.01）. CONCLUSION： L-NAME exerts anti-invasive and anti- metastatic effects on SL-174T cell line via downregulating MNP-2 mRNA expression and upregulating TIMP-2 mRNA expression.

Human epidermal growth factor receptor 2 expression level and combined positive score can evaluate efficacy of advanced gastric cancer

BACKGROUND Although treatment options for gastric cancer(GC)continue to advance,the overall prognosis for patients with GC remains poor.At present,the predictors of treatment efficacy remain controversial except for high microsatellite instability.AIM To develop methods to identify groups of patients with GC who would benefit the most from receiving the combination of a programmed cell death protein 1(PD-1)inhibitor and chemotherapy.METHODS We acquired data from 63 patients with human epidermal growth factor receptor 2(HER2)-negative GC with a histological diagnosis of GC at the Cancer Hospital,Chinese Academy of Medical Sciences between November 2020 and October 2022.All of the patients screened received a PD-1 inhibitor combined with chemotherapy as the first-line treatment.RESULTS As of July 1,2023,the objective response rate was 61.9%,and the disease control rate was 96.8%.The median progression-free survival(mPFS)for all patients was 6.3 months.The median overall survival was not achieved.Survival analysis showed that patients with a combined positive score(CPS)≥1 exhibited an extended trend in progression-free survival(PFS)when compared to patients with a CPS of 0 after receiving a PD-1 inhibitor combined with oxaliplatin and tegafur as the first-line treatment.PFS exhibited a trend for prolongation as the expression level of HER2 increased.Based on PFS,we divided patients into two groups:A treatment group with excellent efficacy and a treatment group with poor efficacy.The mPFS of the excellent efficacy group was 8 months,with a mPFS of 9.1 months after excluding a cohort of patients who received interrupted therapy due to surgery.The mPFS was 4.5 months in patients in the group with poor efficacy who did not receive surgery.Using good/poor efficacy as the endpoint of our study,univariate analysis revealed that both CPS score(P=0.004)and HER2 expression level(P=0.015)were both factors that exerted significant influence on the efficacy of treatment the combination of a PD-1 inhibitor and chemotherapy in patients with advanced GC(AGC).Finally,multivariate analysis confirmed that CPS score was a significant influencing factor.CONCLUSION CPS score and HER2 expression both impacted the efficacy of immunotherapy combined with chemotherapy in AGC patients who were non-positive for HER2.

Inhibitory effect of metformin on the proliferation of human hepatoma HepG2 cells and its potential mechanism

Objective： This work aimed to study the inhibitory effect and the related mechanism of metformin （MET） on the proliferation of human hepatoma HepG2 cells. Methods： Human hepatoma HepG2 cells were treated with MET （0, 2, 10, and 50 mM）. The inhibitory effect of MET on the proliferation of HepG2 cells was determined by MTT method. The apoptosis of HepG2 cells was detected by flow cytornetry. The expression of cyclin D1 in HepG2 cells was examined by Western blot. ROS-DHE fluorescence probe was used to stain the reactive oxygen species （ROS） generated by HepG2 cells after treat- ment. Results： MET could inhibit the proliferation of HepG2 cells in a dose and time dependent manner. MET promoted the apoptosis of HepG2 cells. In addition, MET suppressed the expression of cell cycle protein cyclin D1 and induced the produc- tion of ROS in HepG2 cells. Conclusion： MET can inhibit the proliferation of human hepatoma HepG2 cells and induce cell apoptosis. Meanwhile, MET has the ability to decrease the expression of cyclin D1 and induce ROS generation, which may be involved in the mechanism of inhibiting hepatoma cells proliferation.

野西瓜挥发油对HepG-2细胞线粒体膜电位和Ca^(2+)浓度的影响

目的:探讨野西瓜挥发油(Capparis spinosa L.essential oil,CSEO)对人肝癌HepG-2抑制生长和诱导凋亡作用及其机制。方法:MTT法研究CSEO对人肝癌HepG-2的抑制生长;荧光显微镜观察HepG-2细胞形态;流式细胞仪研究CSEO对HepG-2细胞周期的影响及诱导凋亡作用,罗丹明123单染观察CSEO对线粒体膜电位的改变;激光共聚焦显微镜检测CSEO对HepG-2细胞内Ca2+浓度的影响。结果:CSEO对人肝癌HepG-2细胞生长具有明显的抑制作用,并且有剂量依赖性,IC50为127.5μg·mL-1;CSEO作用48h后,HepG-2细胞在出现特征性凋亡形态特征,300μg·mL-1组的凋亡细胞比率高达44.447%;75和150μg·mL-1下出现G1期细胞阻滞,S期细胞比例下降,G2期细胞比例下降的趋势;CSEO各组线粒体膜电位(Δψm)有所降低,表现为曲线相左移行,此外,中、高浓度的CSEO还可以显著增加细胞内Ca2+浓度。结论:CSEO对人肝癌HepG-2有明显的抑制生长和诱导凋亡作用,其机制可能与线粒体膜电位降低和钙超载有关。

野西瓜总皂苷诱导人肝癌细胞HepG-2凋亡的初步研究

[目的]探讨野西瓜总皂苷(CSS)对人肝癌HepG-2细胞的杀伤作用和诱导凋亡的作用。[方法]四甲基偶氮唑蓝(MTT)法研究CSS对HepG-2细胞的杀伤作用;荧光显微镜观察细胞凋亡形态;碘化吡啶(PI)单染经流式细胞仪检测CSS对HepG-2细胞周期及凋亡的影响。[结果]CSS对HepG-2细胞的生长增殖具有抑制作用;经CSS作用后,HepG-2细胞在出现特征性凋亡形态特征,并出现了G1期阻滞,G2期比例下降,高剂量组出现了G2期消失的现象,50mg/L剂量作用48h,凋亡细胞比率高达66.652%。[结论]CSS对人肝癌HepG-2有明显的杀伤和诱导凋亡作用,并出现细胞周期的改变。

吴茱萸碱调控微管蛋白聚集阻滞HepG-2细胞周期

研究吴茱萸碱对人肝癌细胞HepG-2的细胞周期阻滞作用及其机制.MTT法检测吴茱萸碱(Evodiamine)对人肝癌HepG-2细胞的细胞毒作用;流式细胞仪分析吴茱萸碱对HepG-2细胞周期的影响;免疫荧光染色法,经激光共聚焦显微镜(CLSM)观察检测吴茱萸碱对HepG-2细胞内微管蛋白α-tubulin聚合形态的影响.吴茱萸碱对人肝癌细胞HepG-2的IC50为19.62μmol/L;吴茱萸碱可将HepG-2细胞阻滞于G2/M期;免疫荧光,激光共聚焦显微镜观察可知,吴茱萸碱可显著改变微管蛋白聚合态发生,使细胞内微管呈束状分布,干扰纺锤体形成.实验表明吴茱萸碱通过影响微管蛋白的聚集状态,将HepG-2细胞周期阻滞于G2/M期.

银耳多糖对肝癌细胞株HepG-2增殖的影响

目的:研究银耳多糖对肝癌HepG-2细胞增殖的影响。方法:采用高温浸提的方法提取银耳多糖,并进行提取定量;将银耳多糖作用于肝癌HepG-2细胞,采用台盼蓝排斥试验测定细胞活力和生长曲线。结果:在分别培养1 d、2d和3 d后,银耳多糖干预各组的活细胞率都低于对照组(P<0.001)。生长曲线法显示,银耳多糖干预各组的细胞倍增时间延长,银耳多糖对增殖细胞的杀伤率最高达89.29%(>80%),且存在剂量依赖关系。结论:银耳多糖对肝癌HepG-2细胞具有直接抑制作用。

Relation between the Expression of K-ras in Hep-2 Cells and Development of Laryngeal Carcinoma~*

Objective： To investigate the expression of K-ras in human laryngeal squamous cell carcinoma cell lines （Hep-2） and its significance for establishing a solid foundation for further study of the relationship between human laryngeal squamous cell carcinoma and K-ras gene point mutations. Methods： The expression of K-ras in human laryngeal squamous cell carcinoma cell lines （Hep-2） and human pancreatic carcinoma cell lines （MIAPaCa-2） was detected by using RT-PCR. Results： The expression of K-ras mRNA in Hep-2 and MIAPaCa-2 was strong and positive. Conclusion： The expression of K-ras mRNA in human laryngeal squamous cell carcinoma cell lines （Hep-2） is positive. Development of laryngeal carcinoma might be related to the activation of K-ras gene point mutation.

SOX7靶向ERK1/2/PD-L1通路抑制结直肠癌血管生成

目的探讨性别决定区Y框蛋白7(SOX7)对结直肠癌血管生成的影响及潜在作用机制。方法应用免疫荧光检测结直肠癌患者组织样本中SOX7表达水平,之后通过裸鼠、转染SOX7 mimic的人结直肠癌细胞系SW480细胞和人脐静脉内皮细胞(HUVEC)共培养进一步研究。用Western-blot验证SOX7与ERK1/2/PD-L1对结直肠癌细胞的相关蛋白表达的影响。用CCK8检测SOX7与ERK1/2/PD-L1对HUVEC增殖的影响。通过体外内皮细胞成管实验测定SOX7与ERK1/2/PD-L1对肿瘤血管生成的影响。结果SOX7在人结直肠癌组织中表达被抑制(P<0.01),同时SOX7的过表达抑制了小鼠体内肿瘤生长(P<0.01)。SW480细胞中SOX7的过表达抑制了ERK1/2、c-Jun的表达,并在ERK1/2的激动剂Senkyunolide I的作用下上调了SW480细胞的ERK1/2、c-Jun蛋白表达(P<0.01),逆转了SOX7对SW480细胞中ERK1/2、c-Jun蛋白表达的影响(P<0.01)。HUVEC中SOX7抑制了PD-L1、V-EGFR2、p-PI3K、HIF-1α的蛋白表达,Senkyunolide I上调了HUVEC的PD-L1、V-EGFR2、p-PI3K、HIF-1α的蛋白表达,并逆转了SOX7对HUVEC中上述相关蛋白表达的影响(P<0.01)。PD-1/PD-L1 Inhibitor 3抑制了PD-L1、V-EGFR2、p-PI3K、HIF-1α的蛋白表达,SOX7过表达在PD-1/PD-L1 Inhibitor 3的影响下并没有表现出抑制作用。CCK8实验结果显示SOX7过表达显著抑制了HUVEC的增殖能力,Senkyunolide I作用下的两组HUVEC增殖能力较SOX7 NC组与SOX7 mimic组明显上升,PD-1/PD-L1 Inhibitor 3作用下的两组HUVEC增殖能力较SOX7 NC组与SOX7 mimic组明显下降,以上均有明显统计学差异(P<0.01)。成管实验结果显示SOX7过表达抑制了HUVEC的血管生成,Senkyunolide I强烈加速了血管生成,而PD-1/PD-L1 Inhibitor 3血管生成则被显著抑制,以上均有明显统计学差异(P<0.01)。结论SOX7通过ERK1/2/PD-L1通路抑制结直肠肿瘤的增殖和血管生成,SOX7可能是晚期CRC患者临床治疗中潜在的抗血管生成靶点。

Establishment of an artificial β-cell line expressing insulin under the control of doxycycline

AIM: Artificial beta-cell lines may offer an abundant source of cells for the treatment of type I diabetes, but insulin secretion in beta-cells is tightly regulated in physiological conditions. The Tet-On system is a &quot;gene switch&quot; system, which can induce gene expression by administration of tetracycline (Tet) derivatives such as doxcycline (Dox). Using this system, we established 293 cells to an artificial cell line secreting insulin in response to stimulation by Dox. METHODS: The mutated proinsulin cDNA was obtained from plasmid pcDNA3.1/C-mINS by the polymerase chain reaction (PCR), and was inserted downstream from the promoter on the expression vector pTRE2, to construct a recombined expression vector pTRE2mINS. The promoter on pTRE2 consists of the tetracycline-response element and the CMV minimal promoter and is thus activated by the reverse tetracycline-controlled transactivator (rtTA) when Dox is administrated. pTRE2mINS and plasmid pTK-Hyg encoding hygromycin were co-transfected in the tet293 cells, which express rtTA stably. Following hygromycin screening, the survived cells expressing insulin were selected and enriched. Dox was used to control the expression of insulin in these cells. At the levels of mRNA and protein, the regulating effect of Dox in culture medium on the expression of proinsulin gene was estimated respectively with Northern blot, RT-PCR, and radioimmunoassay. RESULTS: From the 28 hygromycin-resistant cell strains, we selected one cell strain (tet293/Ins6) secreting insulin not only automatically, but in response to stimulation by Dox. The amount on insulin secretion was dependent on the Dox dose (0,10,100,200,400,800 and 1000 microg.L(-1)), the level of insulin secreted by the cells treated with Dox (1000 microg.L(-1)) was 241.0pU.d(-1).cell(-1) , which was 25-fold that of 9.7pU.d(-1).cell(-1) without Dox treatment. Northern blot analyses and RT-PCR further confirmed that the transcription of insulin gene had already been up-regulated after exposing tet293/Ins6 cells to Dox for 15 minutes, and was also induced in a dose-dependent manner. However, the concentration of insulin in the media did not increase significantly until 5 hours following the addition of Dox. CONCLUSION: Human proinsulin gene was transfected successfully and expressed efficiently in 293 cells, and the expression was modulated by tetracycline and its derivatives, improving the accuracy, safety, and reliability of gene therapy, suggesting that conditional establishment of artificial beta-cells may be a useful approach to develop cellular therapy for diabetes mellitus.

Study on preliminary mechanism of apoptosis in HepG-2 by CSA

Objective To study on the mechanism of killing and apoptosis inducing effect of total alkaloid in the CSA(Capparis spinosa L.alkaloid,CSA)on human hepatocarcinoma cell Line HepG-2.Methods The killing effect of the CSA on human hepatocarcinoma cell Line HepG-2 was measured by MTT method.Morphological observation of the HepG-2 cells was completed by fluorescence microscope.The apoptosis inducing effect and changing of mitochondria membrane potential of the CSA on the HepG-2 cells were measured by flow cytometry.In addition,effect of intracellular Ca2+ level of the CSA on the HepG-2 cells was studied by laser confocal microscope.Results The CSA has obvious cytotoxicity on the HepG-2 and seems to be dose-dependent,and its IC50 value is 162.4 μg·mL-1.The HepG-2 cells have characteristic morphologic changes of apoptosis by the function of CSA,and the apoptosis percentage is higher than the natural one.The progress of cells cycle from S phase to G2 phase has been blocked,and the mitochondria membrane potential is markedly decreased,and the intracellular Ca2+ level is increased by the function of CSA.Conclusions The CSA has obviously killing and apoptosis inducing effect on human hepatocarcinoma cell Line HepG-2 by the mechanism of decreasing the mitochondria membrane potential and increasing the intracellular Ca2+ level.

Effect on apoptosis、mitochondrial membrane potential and Ca^(2+) concentration in HepG-2 by CSEO

Objective To study on the mechanism of growth inhibiting and apoptosis inducing effect of total alkaloid in the CSEO(Capparis spinosa L.essential oil,CSEO)on human hepatocarcinoma cell Line HepG-2.Methods The growth inhibiting effect of the CSEO on human hepatocarcinoma cell Line HepG-2 was measured by MTT method.Morphological observation of the HepG-2 cells was completed by fluorescence microscope.The changing of mitochondrion membrane potential induced by CSEO was observed by staining with Rhodamine123.Effect of the CSEO on intracellular Ca2+ level of the HepG-2 cells was measured by laser confocal microscope.Results The CESO has obvious growth inhibiting effect on the HepG-2 and seems to be dose-dependent,and its IC50 is 127.5 μg·mL-1.The characteristic apoptosis morpha of HepG-2 cells has been observed,and the apoptosis percentage increase to 44.447% in the 300 μg·mL-1 dosage group.In addition,the progress of cells cycle of G1 period has been blocked,and the cellular proportion in S and G2 period is decreased in the 75 μg·mL-1 and 150 μg·mL-1 dosage groups by the function of CSEO for 48 h.The mitochondria membrane potential(Δψm)effected by CESO is decreased,while the curve moves toward left.In addition,the intracellular Ca2+ level is increased by the function of CESO in the middle and high dose groups.Conclusions The CESO has obviously growth inhibiting and apoptosis inducing effect on human hepatocarcinoma cell Line HepG-2 by the mechanism of decreasing the mitochondria membrane potential and increasing the intracellular Ca2+ level.

LncRNA FEZF1-AS1通过调控EZH2对肺间质细胞增殖、迁移及侵袭的作用

目的研究长链非编码RNA FEZ家族锌指1-反义RNA 1(lncRNA FEZF1-AS1)调控zeste同源物增强子2(EZH2)对肺间质细胞增殖、迁移、侵袭能力及上皮细胞-间质转化(EMT)的影响及其作用机制。方法将人肺腺癌细胞系A549分为对照组(control)和模型组[model,用转化生长因子β1(TGF-β1)20 ng/mL作用48 h,诱导成为肺间质细胞]。用Western blot检测细胞中E-钙黏蛋白(E-cadherin)、N-钙黏蛋白(N-cadherin)及波形蛋白(vimentin)的蛋白表达。RT-qPCR检测细胞中lncRNA FEZF1-AS1和EZH2基因表达。转染组细胞分为转染si NC组、si lncRNA FEZF1-AS1+OE vector组和si lncRNA FEZF1-AS1+OE EZH2组。CCK-8法检测细胞增殖、细胞划痕检测细胞迁移、Transwell小室法检测细胞侵袭;用Western blot检测细胞中E-cadherin、N-cadherin、vimentin及EZH2的蛋白表达,用RNA免疫沉淀(RIP)测定FEZF1-AS1与EZH2的直接结合作用。结果与对照组比较,模型组E-cadherin的蛋白表达水平减少(P<0.05);N-cadherin及vimentin的蛋白表达水平升高(P<0.05);与对照组比较,模型组lncRNA FEZF1-AS1与EZH2基因的表达水平明显升高(P<0.05);与si NC组相比,si lncRNA FEZF1-AS1+OE vector组细胞增殖、迁移、侵袭能力降低,E-cadherin蛋白表达升高,N-cadherin、vimentin、EZH2蛋白表达降低(P<0.05);与si lncRNA FEZF1-AS1+OE vector组比较,si lncRNA FEZF1-AS1+OE EZHZ组细胞增殖、侵袭、迁移能力升高,E-cadherin蛋白表达降低,N-cadherin、vimentin、EZH2蛋白表达升高(P<0.05);RIP实验进一步证实了lncRNA FEZF1-AS1与EZH2具有结合作用。结论LncRNA FEZF1-AS1通过调控EZH2促进肺间质细胞增殖、侵袭、转移和EMT过程。

Effect of Calmodulin and Voltage-dependent Ca^(2+) Channel on the Proliferation of Heptoma Cells Induced by Epidermal Growth Factor

The effect of thyrosine kinase, calmodulin and voltage-dependent Ca 2+ channel on the proliferation of hepatoma cells induced by EGF was studied. Hepatoma cell line SMMC7721 was cultured in RPMI1640 serum-free medium. DNA synthesis rate of hepatoma cells was measured by 3H-TdR incorporation. 10 -9 mol/L EGF could significantly stimulate the proliferation of hepatoma cells (P<0.05), and this effect might be significantly inhibited by tyrosine kinase inhibitor (P<0.001). Calmodulin inhibitor W-7 had no effect on the basic phase of cultured hepatoma cells (P> 0.05), but it had very significantly inhibitory effect on the proliferation of hepatoma cells induced by EGF (P<0.001). Voltage-dependent Ca 2+ channel inhibitor Varapamil had no inhibition on the proliferation of hepatoma cells induced by EGF (P>0.05). It had no effect on the basic phase of cultured hepatoma cells (P>0.05). It is suggested that tyrosine kinase and Ca 2+-calmodulin-dependent pathway may play a critical role on the proliferation of heptoma cells induced by EGF, and voltage-dependent Ca 2+ channel is independent of the effect of EGF.

Inhibitory effects of apogossypolone on subcutaneous implants of human LNCaP prostatic carcinoma cells

Objective:The aim of this study was to investigate the inhibitory effect of apogossypolone (ApoG2) on subcutaneous implants of human LNCaP prostatic carcinoma cells, and explore its mechanism. Methods:To establish human LNCaP prostatic carcinoma cell line subcutaneous xenograft models and observe the inhibitory effect of ApoG2 on the tumor model. Immunohistochemistry was employed to observe the expression of Bcl-2, PCNA, CD31, caspase-3 and-8 in tumor tissues. The microvessel density was calculated. Results:ApoG2 could obviously inhibit the growth of subcutaneous prostatic carcinoma implant. ApoG2 decreased the expression of PCNA and CD31, and increased the expression of caspases-3,-8 in tumor tissues. Conclusion:ApoG2 has an inhibitory effect on prostatic carcinoma implants.

构建过表达TRPV1基因的Caco-2细胞株

采用慢病毒载体系统构建辣椒素受体基因TRPV1过表达的人结直肠腺癌细胞Caco-2稳定重组株.将双酶切后的慢病毒空载体pCDH和TRPV1全基因PCR产物通过T4 DNA Ligase连接,构建包含TRPV1基因的过表达载体pCDH-TRPV1.将过表达载体pCDH-TRPV1转化DH 5α感受态细菌,大量扩繁后提取过表达载体pCDH-TRPV1的质粒,与psPAX2和pMD两种含有慢病毒包装所必需元件的质粒混合,再与脂质体混合制备脂质体-载体混合液.将脂质体-载体混合液转染至单层的293T细胞中,培养48h进行病毒包装.收集富含慢病毒颗粒的293T细胞上清液,超离心纯化成浓缩病毒,然后再与polybrene一起感染单层Caco-2细胞,通过GFP绿荧光信号来筛选获得TRPV1基因过表达的稳定细胞株.通过Realtime PCR方法和Western-blot检测TRPV1的mRNA表达量及蛋白表达量,结果表明,Caco-2-TRPV1重组细胞株的TRPV1的mRNA表达量及蛋白表达量均显著高于Caco-2-GFP对照细胞(P<0.05).成功构建了TRPV1基因过表达的稳定细胞株,为后续辣椒素降脂机理的研究提供了正向调控细胞模型.

两性霉素B通过激活THP-1细胞TLR2/NF-κB信号通路对炎症因子IL-1β释放的影响

目的:探讨两性霉素B对人急性单核细胞白血病细胞系(THP-1)Toll样受体2(TLR2)/核转录因子(NF-κB)信号通路及产生白细胞介素-1β(IL-1β)的影响。方法:采用逆转录聚合酶链反应(RT-PCR)检测两性霉素B及阳性刺激物肽聚糖(PGN)刺激THP-1细胞后TLR2、IL-1β的mRNA表达水平。TLR2单克隆抗体预先和THP-1细胞共培养,再用两性霉素B及PGN刺激THP-1细胞后检测IL-1β的mRNA表达水平。采用酶联免疫吸附法检测IL-1β分泌量。采用免疫印迹法分析两性霉素B作用于THP-1细胞不同时间后NF-κB抑制蛋白α(IκBα)和磷酸化IκBα蛋白表达水平,激光共聚焦分析NF-κB p65入核水平,并用TLR2抗体阻断后检测IκBα和磷酸化IκBα蛋白表达水平。结果:刺激后1、3、6h,两性霉素B组与空白对照组TLR2和IL-1βmRNA表达水平比较,差异有统计学意义(P<0.05);刺激后1、3、6h,两性霉素B组和PGN组TLR2和IL-1βmRNA表达水平比较,差异无统计学意义(P>0.05)。两性霉素B组和PGN组上清液中IL-1β的含量与空白对照组比较,差异有统计学意义(P<0.05)。两性霉素B作用于THP-1细胞30min后磷酸化IκBα蛋白水平升高,激光共聚焦显示p65入核。使用TLR2单克隆抗体后,两性霉素B组、PGN组与本组未用TLR2单克隆抗体的IL-1βmRNA表达水平比较,差异有统计学意义(P<0.05);未用抗体及使用抗体情况下,两性霉素B组、PGN组和空白对照组的IL-1βmRNA表达水平比较,差异均有统计学意义(P<0.05)。结论:两性霉素B作用于THP-1细胞,激活TLR2/NF-κB信号通路,参与下游炎症因子IL-1β释放。

尼美舒利对人食管癌细胞Eca-109 COX-2表达及生长的抑制作用

目的研究环氧化酶-2(COX-2)选择性抑制剂尼美舒利对人食管癌Eca-109细胞株COX-2表达和细胞增殖及凋亡的影响。方法MTT法测定尼美舒利对人食管癌Eca-109细胞增殖的抑制率;RT-PCR法检测Eca-109细胞COX-2mRNA表达变化;流式细胞仪检测COX-2蛋白表达、细胞周期时相分布及凋亡率的变化;光镜和琼脂糖电泳法进一步观察细胞凋亡。结果尼美舒利对人食管癌Eca-109细胞有较强的抑制作用,有明显的时间和浓度依赖性;呈浓度依赖性下调Eca-109细胞COX-2 mRNA及蛋白表达;可使Eca-109细胞G0/G1期比例增高,S期细胞减少,增殖指数降低,凋亡细胞增多。结论尼美舒利可能通过对COX-2表达的下调而诱导凋亡和细胞周期阻滞,从而抑制人食管癌Eca-109细胞生长。