Crebanine N-oxide, a natural aporphine alkaloid isolated from Stephania hainanensis, induces apoptosis and autophagy in human gastric cancer SGC-7901 cells

Objective: To investigate the cytotoxic effects and the potential mechanisms of crebanine N-oxide in SGC-7901 gastric adenocarcinoma cells. Methods: The cytotoxicity of crebanine N-oxide was evaluated by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay and cellular morphology was observed under a microscope. Cell apoptosis was determined by flow cytometry using propidium iodide staining. The expression levels of apoptotic-related proteins, cleaved caspase-3, cytochrome C, p53 and Bax, and autophagyrelated proteins p62, beclin1 and LC3 were detected by Western blotting assays. Results: Crebanine N-oxide treatment significantly inhibited the proliferation of SGC-7901 cells in a dose-dependent and timedependent manner via induction of G2-phase cell cycle arrest, apoptosis, and autophagy in SGC-7901 cells.Conclusions: Crebanine N-oxide could inhibit the growth of gastric cancer cells by promoting apoptosis and autophagy and could be used as a potential agent for treating gastric cancer.

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.

Induction of apoptosis and G2/M cell cycle arrest by oridonin in human gastric cancer BGC-823 cells

Aim To investigate in vitro apoptosis-induction effects of oridonin on gastric tumor cells BGC-823 and its effects on cell cycle, mitochondrial membrane potential and intracellular Ca^2＋ to shed light on the mode of its anticancer action. Methods The MTT method was used to investigate the inhibitory effect of oridonin on BGC-823 cells. The apoptosis-induction effect was evaluated by confocal laser microscopy and flow cytometry. The change of mitochondrial membrane potential and the increase of intracellular Ca^2＋ were assessed by fluorescence probe rhodamine123 and Fluo 3-AM, respectively, with flow cytometry. The expression of apoptosis and cell cycle related proteins was studied using western blotting. Results Oridonin inhibited BGC-823 cells growth with IC50 of 22.21 p, mol.L^-1. It induced apoptosis in a dose-dependent manner. In addition, it decreased mitochondria membrane potential, increased intracellular Ca^2＋, and activated pro-caspase 3. BGC-823 cells were arrested in G2/M cell cycle phase with lower expression of cyclin A protein. The up-regulation of p53 was observed before apoptosis and cell cycle arrest occurred. Conclusion Oridonin inhibits the proliferation of BGC-823 cells through G2/M cell cycle arrest and apoptosis induction, which is mediated by influx of Ca^2＋, up-regulation of p53, activation of caspase-3, and down-regulation of cyclin A.

The Effect of Nimesulide on the Expression of NF-κB,Bcl-2 and Bax in the Human Gastric Cancer SGC-7901 Cell Line

OBJECTIVE To investigate whether nimesulide can suppress tumor growth and induce apoptosis in SGC-7901 gastric cancer cells and to explore the molecular mechanism involved. METHODS SGC-7901 cells were cultured in RPMI 1640 medium containing different concentrations of nimesulide （0,12.5, 50, 100, 200, 400 μmol/L）. The MTT assay, morphological observation, electron microscopy （EM）, immunohistochemical analysis and Western blot analysis were employed to investigate the effects of nimesulide on the SGC-7901 cells and to explore possible related molecular mechanisms. RESULTS Nimesulide inhibited the growth of SGC-7901 cells and elicited typical apoptotic morphologic changes. Nimesulide also decreased NF-κB and Bcl-2 expression, but increased the level of the Bax protein. The positive rate of Bcl-2 protein expression at 0, 50, 100 and 200 μmol/L of nimesulide was 58.3±14.0%, 50.2±9.9%, 32.8±5.0% and 22.7±5.5% respectively based on immunohistochemical staining. The positive rate of Bax protein expression was 22.0±5.7%, 29.2±6.5%, 42.7±5.9% and 74.5±9.1% and the NF-κB expression was 74.2±10.9%, 61.8±7.6%, 36.7±10.9% and 17.5±12.3%, Significant differences were found between so μmol/L and 100 μmol/L and 200μmol/L. Western blot analysis also showed that the expression of NF-κB was decreased. CONCLUSION Nimesulide suppresses tumor growth and induces apoptosis by inhibiting NF-κB expression, which may be related to the overexpression of Bax relative to Bcl-2 expression.

秦皮乙素对人胃癌SGC-7901细胞增殖、迁移、侵袭和糖酵解的影响

目的探讨秦皮乙素(AES)对胃癌SGC-7901细胞增殖、迁移、侵袭和糖酵解的影响及相关机制。方法采用MTT法检测细胞增殖活性;采用划痕实验和Transwell实验检测细胞迁移和侵袭能力;葡萄糖摄取量测定和乳酸含量测定实验检测细胞糖酵解情况;Western blot法检测迁移、侵袭及糖酵解相关蛋白的表达水平。结果AES能够抑制SGC-7901细胞的增殖活力,且这种抑制效果与AES的剂量成正相关。随着AES剂量的梯度增加,SGC-7901细胞的迁移、侵袭及糖酵解能力逐渐降低(P<0.05)。AES可以下调SGC-7901细胞HIF-1α、MMP-2、MMP-9、GLUT1、LDHA蛋白的表达水平(P<0.05)。结论AES对人胃癌SGC-7901细胞增殖活性及迁移、侵袭能力有抑制作用,通过抑制人胃癌SGC-7901细胞的葡萄糖摄取及乳酸生成降低糖酵解水平。AES可能通过影响缺氧诱导因子HIF-1α抑制SGC-7901细胞迁移、侵袭及有氧糖酵解过程。

Growth inhibitory effect of 4-phenyl butyric acid on human gastric cancer cells is associated with cell cycle arrest

AIM: To investigate the growth effects of 4-phenyl butyric acid (PBA) on human gastric carcinoma cells and their mechanisms. METHODS: Moderately-differentiated human gastric carcinoma SGC-7901 and lowly-differentiated MGC-803 cells were treated with 5, 10, 20, 40, and 60 μmol/L PBA for 1-4 d. Cell proliferation was detected using the MTT colorimetric assay. Cell cycle distributions were examined using flow cytometry.RESULTS: The proliferation of gastric carcinoma cells was inhibited by PBA in a doseand time-dependent fashion. Flow cytometry showed that SGC-7901 cells treated with low concentrations of PBA were arrested at the G0/G1 phase, whereas cells treated with high concentrations of PBA were arrested at the G2/M phase. Although MGC-803 cells treated with low concentrations of PBA were also arrested at the G0/G1 phase, cells treated with high concentrations of PBA were arrested at the S phase. CONCLUSION: The growth inhibitory effect of PBA on gastric cancer cells is associated with alteration of the cell cycle. For moderately-differentiated gastric cancer cells, the cell cycle was arrested at the G0/G1 and G2/M phases. For lowly-differentiated gastric cancer cells, the cell cycle was arrested at the G0/G1 and S phases.

Human induced pluripotent stem cells labeled with fluorescent magnetic nanoparticles for targeted imaging and hyperthermia therapy for gastric cancer

Objective: Human induced pluripotent stem(i PS) cells exhibit great potential for generating functional human cells for medical therapies. In this paper, we report for use of human i PS cells labeled with fluorescent magnetic nanoparticles(FMNPs) for targeted imaging and synergistic therapy of gastric cancer cells in vivo. Methods: Human i PS cells were prepared and cultured for 72 h. The culture medium was collected, and then was coincubated with MGC803 cells. Cell viability was analyzed by the MTT method. FMNP-labeled human i PS cells were prepared and injected into gastric cancer-bearing nude mice. The mouse model was observed using a small-animal imaging system. The nude mice were irradiated under an external alternating magnetic field and evaluated using an infrared thermal mapping instrument. Tumor sizes were measured weekly. Results: iP S cells and the collected culture medium inhibited the growth of MGC803 cells. FMNP-labeled human iP S cells targeted and imaged gastric cancer cells in vivo, as well as inhibited cancer growth in vivo through the external magnetic field. Conclusion: FMNP-labeled human i PS cells exhibit considerable potential in applications such as targeted dual-mode imaging and synergistic therapy for early gastric cancer.

连翘提取物FS-4体外诱导胃癌细胞SGC-7901凋亡作用的研究

为了探讨连翘提取物FS-4体外对胃癌细胞SGC-7901的促凋亡作用,试验采用MTT比色法观察了FS-4对胃癌细胞SGC-7901增殖的抑制情况,AO/EB双荧光染色法和透射电子显微镜观察了细胞凋亡的形态学变化,并通过流式细胞术测定细胞的凋亡率。结果表明:FS-4对胃癌细胞SGC-7901增殖的抑制作用具有剂量和时间依赖性,其36 h的半数抑制浓度(IC_(50))仅为3.23μg/mL;FS-4作用后细胞均出现典型的凋亡细胞形态;FS-4对细胞的诱导凋亡作用呈现明显的浓度依赖性。说明FS-4可抑制胃癌细胞SGC-7901的增殖并具有诱导其凋亡的作用。

The Mechanism pf Weichang'an in Inducing Apoptosis of Gastric Cancer SGC7901 Cells

Objective:To investigate the effect of Chinese medicine Compound Weichang'an(胃肠安)for invig-orating the spleen on apoptosis of gastric cancer SGC7901 cells and its possible mechanism.Methods:The gas-trie cancer SGC-7901 cells were divided into different mass concentration groups(0 mg·L^(-1),500 mg·L^(-1)1000 mg·L^(-1),1500 mg·L^(-1),2000 mg·L^(-1)).CCK8 and monoclonal test were applied to detect prolifera-tion ability;comet assay was used to detect DNA damage.After DCFH-DA fluorescent labeling,the level of ROS activity was detected by flow cytometer;after AnnexinV-FTC/PI double labeling,the proportion of apoptotic ellls was detected by flow cytometer;after JC-1 staining,the mi tochondri almembrane potential was detected by flow cytometer;after FTTC-DEVD-FMK staining,the ratio of Caspase activity was detected by flow cytometer.Results:Weichang an inhibited cell proliferation and reduced cell colony formation in a time-dose-dependent manner;the results of comet electrophoresis showed that Weichang'an could induce DNA damage in gastric cancer cells;com-pared with control group.the ratio of Weichang'an's intervention with the apoptosis of gastric cancer cells in-creased(P<0.05),the mitochondrial membrane potential decreased(P<0.05),the activity of Caspase3 and Caspase9 increased(P<0.05),and the intracellular ROS level increased(P<0.05).Among them,the effect of Weichang'an treatment group(1000 mg·L^(-1))was the most significant.Conclusion:Weichang'an has an inhibi-tory effect on the proliferation of gastric cancer SGC7901 cells and can induce cell apoptosis.Its mechanism may be related with the ROS-mediated pathway of mitochondrial apoptosis and DNA damage.

Low intensity ultrasound-induced apoptosis in human gastric carcinoma cells

AIM： To investigate the low intensity ultrasound （US）- induced apoptosis in human gastric carcinoma cells and its potential mechanism and to suggest a new therapeutic approach to gastric carcinoma. METHODS： Human SGC-7901 gastric carcinoma cells were cultured in vitro and irradiated by low intensity US for 10 min at different intensities with different incubation times after irradiation. Morphologic changes were examined under microscope with trypan blue staining and then the percentage of early apoptotic cells was detected by flow cytometry （FCM） with double staining of fiuorescein isothiocyanate （FITC）- Annexin V/propidium iodide （PI）. Two-dimensional electrophoresis （2DE） was used to get the protein profile and some proteins differently expressed after US irradiation were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS）. Functional analysis was performed to investigate the mechanism of US-induced cell apoptosis. RESULTS： The percentage of apoptotic cells increased about 10% after US irradiation （12.0 W/cm^2, 12 h culture）, The percentage of early apoptosis and secondary necrosis in the US-irradiated cells increased with the increased US intensity. Moreover, apoptotic cells increased with the increased culture time after US irradiation and reached its maximum at about 12 h.Several new proteins appeared after US irradiation and were up or down regulated more than 2 times. Some heat shock proteins （HSPs） were found to be associated with the signal process simulating the apoptosis of cells. CONCLUSION： Low intensity US could induce apoptosis in human gastric carcinoma cells. US-induced apoptosis is related to US intensity/culture time. US-induced apoptosis may be caspases-dependent and endoplasmic reticulum （ER） stress-triggered apoptosis may also contribute to it. Proteomic experimental system is useful in finding the protein alteration in carcinoma cells after US irradiation, helping to develop a new cancer therapy.

Apoptosis mechanisms of human gastric cancer cell line MKN-45 infected with human mutant p27

AIM: To explore the inducing effect of human mutant p27 gene on the apoptosis of the human gastric cancer cell line MKN-45 and its associated mechanisms. METHODS: The recombinant adenovirus Ad-p27mt was constructed to infect the human gastric cancer cell line MKN-45. Using flow cytometry, TUNEL assay and DNA fragment analysis, we measured the apoptotic effect of Ad-p27mt on the human gastric cancer cells. RESULTS: Ad-p27mt was successfully constructed and the infection efficiency reached 100%. After 18 h of infection, we observed an apoptotic hypodiploid peak on the flow cytometer before G1-S and apoptotic characteristic bands in the DNA electrophoresis. The apoptotic rate detected by TUNEL method was significantly higher in the Ad-p27mt group (89.4±3.12%)compared to the control group (3.12±0.13%, P ＜ 0.01).CONCLUSION: Human mutant p27 can induce apoptosis of the human gastric cancer cells in vitro.

Study on biological characters of SGC7901 gastric cancer cell-dendritic cell fusion vaccines

AIM： To detect the biological characters of the SGC7901 gastric cancer cell-dendritic cell fusion vaccines.METHODS： The suspending living SGC7901 gastric cancer cells and dendritic cells were induced to be fusioned by polyethylene glycol. Pure fusion cells were obtained by selective culture with the HAT/HT culture systems. The fusion cells were counted at different time points of culture and their growth curves were drawn to reflect their proliferative activities. The fusion cells were also cultured in culture medium to investigate whether they could grow into cell clones. MTT method was used to test the stimulating abilities of the fusion cells on T lymphocytes＇ proliferations. Moreover, the fusion cells were planted into nude mice to observe whether they could grow into new planted tumors in this kind of immunodeficiency animals.RESULTS： The fusion cells had weaker proliferative activity and clone abilities than their parental cells. When they were cultured, the counts of cells did not increase remarkably, nor could they grow into cell clones in culture medium. The fusion cells could not grow into new planted tumors after planted into nude mice. The stimulating abilities of the fusion cells on T lymphocytes＇ proliferations were remarkably increased than their parental dendritic cells. CONCLUSION： The SGC7901 gastric cancer cell-dendritic cell fusion vaccines have much weaker proliferative abilities than their parental cells, but they keep strong abilities to irritate the T lymphocytes and have no abilities to grow into new planted tumors in immunodeficiency animals. These are the biological basis for their antitumor biotherapies.

Gastric cancer cell lines induced by trichostatin A

AIM： To explore the effect of trichostatin A （TSA） on apoptosis and acetylated histone H3 levels in gastric cancer cell lines BGC-823 and SGC-7901. METHODS： The effect of TSA on growth inhibition and apoptosis was examined by MTT, fluorescence microscopy and PI single-labeled flow cytometry. The acetylated histone H3 level was detected by Western blot. RESULTS： TSA induced apoptosis in gastric cancer cell lines BGC-823 and SGC-7901 was in a dose and time-dependent manner. Apoptotic cells varied significantly between TSA treated groups （37.5 ng/mL 72 h for BGC-823 cell line and 75 ng/mL 72 h for SGC-7901 cell line） and control group （0.85 ± 0.14 vs 1.14 ± 0.07, P = 0.02; 0.94 ± 0.07 vs 1.15 ± 0.06, P = 0.02）. Morphologic changes of apoptosis, including nuclear chromatin condensation and fluorescence strength, were observed under fluorescence microscopy. TSA treatment in BGC-823 and SGC-7901 cell lines obviously induced cell apoptosis, which was demonstrated by the increased percentage of sub-G1 phase cells, the reduction of Gl-phase cells and the increase of apoptosis rates in flow cytometric analysis. The result of Western blot showed that the expression of acetylated histone H3 increased in BGC-823 and SGC-7901 TSA treatment groups as compared with the control group.CONCLUSION： TSA can induce cell apoptosis in BGC-823 and SGC-7901 cell lines. The expression of acetylated histone H3 might be correlated with apoptosis.

苦荞异槲皮苷对人胃癌细胞SGC-7901增殖及凋亡的影响

从苦荞中提取制备异槲皮苷,研究其对人胃癌细胞SGC-7901增殖、凋亡、迁移和细胞周期的影响。将异槲皮苷作用于人胃癌SGC-7901细胞和人肾上皮细胞系293T,通过噻唑蓝法检测异槲皮苷对其增殖的影响;4’,6-二脒基-2-苯基吲哚(4’,6-diamino-2-phenyl indole,DAPI)荧光染色法观察细胞核的形态学变化;划痕擦伤迁移实验检测异槲皮苷对SGC-7901细胞迁移能力的影响;流式细胞术检测异槲皮苷对SGC-7901细胞凋亡及细胞周期的影响。结果表明:苦荞异槲皮苷可以抑制SGC-7901细胞的增殖,并呈时间和剂量依赖性,当用100μmol/L异槲皮苷作用细胞48 h后,对SGC-7901细胞的增殖抑制率达到35.92%,而对人肾上皮细胞系293T的增殖抑制率仅为3.15%;DAPI荧光染色法观察异槲皮苷处理细胞后,染色体凝聚,有凋亡小体产生;划痕擦伤实验显示,异槲皮苷能抑制SGC-7901细胞的迁移;流式细胞术检测结果表明,异槲皮苷可使G1和S期细胞减少,G2/M期细胞增多,且细胞凋亡率明显增加。综上所述,苦荞麦异槲皮苷能够诱导SGC-7901细胞发生凋亡,阻断细胞周期并抑制细胞增殖和迁移。

半枝莲抑制胃癌SGC-7901细胞浸润转移作用及机理

目的研究半枝莲提取物抑制人胃癌SGC-7901细胞浸润转移的作用及机理。方法采用MTT比色法检测半枝莲提取物对人胃癌SGC-7901细胞的抑制作用;采用不同浓度梯度半枝莲提取物干预细胞,应用AnnexinV-FITC/PI双染色凋亡试剂盒,通过流式细胞仪观察细胞的凋亡情况。结果半枝莲提取物能显著地抑制SGC-7901细胞的增殖,并具有浓度依赖性;作用16 h后,细胞生长密度变疏,细胞皱缩,其中95%氯仿半枝莲提取物高浓度组大部分细胞破碎;细胞有明显的凋亡改变。半枝莲黄酮类化合物B作用肿瘤细胞后uPA的表达与阴性对照组相比显著减弱,并呈现统计学意义(P<0.01)。结论半枝莲提取物具有抗胃癌SGC-7901细胞增殖和诱导胃癌细胞凋亡的作用,并能降低uPA的表达。

人参皂苷CK对胃癌细胞株SGC-7901及其内源性VEGF的影响

目的研究人参皂苷CK对胃癌SGC-7901细胞增殖、细胞周期的影响及其对内源性分泌的血管内皮细胞生长因子(VEGF)的作用。方法以50、25、12.5、6.25、3.125、1.5625μg/ml的人参皂苷CK作用于胃癌细胞株SGC-7901,通过MTT法检测人参皂苷CK对细胞的抑制作用;采用流式细胞术检测细胞周期和细胞凋亡;ELISA定量检测细胞培养液中内源性VEGF的含量变化。结果 MTT法显示人参皂苷CK对胃癌细胞株SGC-7901有抑制作用,并且呈浓度、时间依赖关系;SGC-7901细胞经人参皂苷作用后出现明显凋亡峰,且细胞周期被阻滞在G0/G1期;人参皂苷CK处理组VEGF含量低于对照组(P<0.05),高浓度组低于低浓度组(P<0.05),且随着作用时间延长,VEGF含量降低。结论人参皂苷CK可通过诱导凋亡抑制胃癌细胞株SGC-7901生长,并可抑制SGC-7901细胞内源性分泌VEGF,人参皂苷CK可能成为一种潜在的抗胃癌药物。

芫菁体内结合斑蝥素对胃癌SGC-7901细胞增殖的抑制作用

本文考察了芫菁体内结合斑蝥素和人工合成的斑蝥素盐类衍生物斑蝥素酸镁的体外抗肿瘤活性。采用WST-1法检测两者在体外对人胃腺癌SGC-7901细胞增殖的抑制作用。实验结果显示两者对SGC-7901细胞均表现出明显的抑制效果,且随药物浓度升高其抑制作用增强,呈剂量效应关系;其半数抑制浓度(IC50)分别为10.86和8.65μmol/L。此外,通过流式细胞术检测表明,结合斑蝥素能引起SGC-7901细胞G0～G1期阻滞;斑蝥素酸镁则引起SGC-7901细胞S期阻滞,两者均能通过干预SGC-7901细胞的周期来抑制其增殖。

体外扩增CIK细胞杀伤胃癌细胞SGC-7901

目的：观察CIK细胞增殖情况，了解扩增后的最佳应用时机，并观察体外对SGC-7901的杀伤作用。方法：健康人外周血单核细胞（PBMC）在体外条件下经过多种细胞因子的共同刺激诱导成CIK细胞，计数培养不同时间的CIK细胞，用流式细胞术检测CIK细胞的表型特征。用MTT法检测杀伤活性，对比CIK细胞与5-FU对SGC-7901的杀伤作用，并观察了两者联合应用的效果。结果：CIK细胞随体外培养时间的延长，数量及杀伤活性均增加。体外培养20d增殖124倍，CD3^＋、CD56^＋双阳性细胞的比例达66．1％，其后两者数量增长缓慢；体外实验显示CIK细胞对胃癌SGC-7901细胞株有明显的杀伤作用，最高杀伤效率为73．13％，其杀伤作用优于5-FU，P〈0．05。二者联合应用杀伤作用降低。结论：CIK细胞具有较强的抗胃癌细胞活性；体外培养15～20d时应用较为合适；联合应用时5-FU可降低CIK细胞的杀伤效率。

miR-140在人胃癌组织中的表达及对SGC-7901胃癌细胞功能的影响

目的:研究microRNA-140(miR-140)在人胃癌和正常胃组织中的表达水平,以及调控miR-140表达后对SGC-7901胃癌细胞功能的影响。方法:采用实时荧光定量PCR检测miR-140在人胃癌和正常胃组织中的表达水平;将miR-140 mimics(miR-140上调表达)和miR-140 inhibitors(miR-140下调表达)分别通过脂质体转染至人胃癌SGC-7901细胞中,同时设置未转染对照组(control组)和miRNA无义序列转染对照组(NC组)。实时荧光定量PCR检测转染后各组细胞中miR-140的表达变化;MTT方法检测各组细胞的生长活力和顺铂(DDP)作用下的生长抑制率;流式细胞术检测各组的细胞周期和凋亡率;Transwell实验检测各组细胞侵袭能力;Western blot检测各组细胞中组蛋白脱乙酰酶4(HDAC4)蛋白表达。结果:miR-140在人胃癌组织中表达水平显著低于正常胃组织(P<0.05)。与control和NC组相比,miR-140 mimics组中SGC-7901细胞活力和侵袭能力下降,细胞周期被阻滞,DDP作用下细胞生长抑制率和凋亡率上升,且HDAC4蛋白表达下调,差异均有统计学意义(P<0.05);而miR-140 inhibitors组中SGC-7901细胞活力和侵袭能力上升,细胞周期被促进,DDP作用下细胞生长抑制率和凋亡率下降,且HDAC4蛋白表达上调,差异均有统计学意义(P<0.05)。结论:miR-140在胃癌组织中低表达,可作为抑癌因子调控胃癌细胞活力、细胞周期变化、凋亡、侵袭并通过下调HDAC4发挥作用。miR-140可能作为胃癌诊断和治疗的新靶点。

D-氨基葡萄糖衍生物对人胃癌细胞系SGC-7901增生的影响

目的:观察D-氨基葡萄糖衍生物体外对人胃癌SGC- 7901细胞增生的影响,探讨其可能作用机制. 方法:采用MTT法,筛选药物作用最佳浓度.用流式细胞仪分析诱导凋亡前后的细胞DNA含量,透射电镜观察凋亡细胞的超微结构.免疫组化测定CD44表达. 结果:D-氨基葡萄糖衍生物能明显抑制胃癌细胞的增长(P<0.01),MTT法显示抑制程度具有时间和剂量效应关系,统计组间比较差异有显著性(P<0.01);流式细胞仪分析可见亚二倍体(Sub-G1)凋亡峰;电镜观察到凋亡细胞的典型变化,免疫组化及光密度检测示CD44表达下降(216.5±7.0 vs 190.0±14.2,P=0.000). 结论:D-氨基葡萄糖衍生物通过诱导肿瘤细胞凋亡而抑制人胃癌SGC-7901细胞增生,同时还有下调CD44的作用.