miR-106a靶向调控TIMP2对人胃癌细胞增殖、转移及EMT的影响

目的 探讨微小RNA-106a(miR-106a)在人胃癌组织中的表达及其与癌细胞增殖、转移的关系。方法 收集人胃癌和配对癌旁福尔马林固定-石蜡包埋样本共50对,Real-time PCR法检测miR-106a在人胃癌组织中的表达;培养人低分化胃癌细胞系SGC-7901、BGC-823、MKN-45和永生化人胃黏膜上皮细胞GES-1,Real-time PCR法检测miR-106a在人胃癌细胞中的表达;MTT法检测细胞增殖,Transwell法检测细胞迁移和侵袭,生物信息学和双荧光素酶法鉴定miR-106a靶基因,Western blot检测靶蛋白TIMP2、MMP2、MMP9、E-cadherin、N-cadherin表达。结果 Real-time PCR检测显示,与癌旁组织比较,miR-106a在人胃癌组织中高表达,差异有统计学意义(P＜0.001);与GES-1细胞比较,miR-106a在人胃癌细胞SGC-7901、BGC-823、MKN-45中普遍高表达,差异有统计学意义(P＜0.001)。MTT检测显示抑制miR-106a后胃癌细胞SGC-7901、BGC-823增殖能力下降(P＜0.01)。Transwell显示胃癌细胞BGC-823迁移、侵袭能力下降(P＜0.001)。双荧光素酶法显示TIMP2野生型报告基因与miR-106a mimic共转后,其荧光素酶活性较miR-106a NC组明显下降(P＜0.001),但TIMP2突变型报告基因无明显变化。Western blot显示抑制miR-106a后TIMP2表达升高,MMP2、MMP9表达下降,E-cadherin表达升高,N-cadherin表达下降。结论 miR-106a在人胃癌中的高表达可能通过靶向TIMP2而影响癌细胞的增殖、转移和上皮-间质转化。     

miR-34a regulates cisplatin-induce gastric cancer cell death by modulating PI3K/AKT/survivin pathway

The purposes of this study were to determine the expression profiles of microRNA-34a (miR-34a) in human gastric cancer cell line (SGC-7901) and cisplatin-resistant cell lines (SGC-7901/DDP), and to establish the correlation between miR-34a expression profile and the sensitivity of human gastric cancer cell to cisplatin-based pattern, thereby providing new methods and strategies for treating gastric cancer. Gastric cancer cell line (SGC-7901) and cisplatin-resistant cell line (SGC-7901/DDP) were cultivated in vitro, respectively. Quantitative real-time PCR (qRT-PCR) and Western blot were utilized to determine the expression profiles of miR-34a and survivin in both gastric cancer cell lines. With miR-34a mimic and miR-34a inhibitor transfected into SGC-7901 and SGC-7901/DDP for 48 h, post-transfection changes of miR-34a expression was determined; the effects of miR-34a ectopic expression on the viability of cisplatin-induce gastric cancer cell were assayed by the MTT method. The effects of miR-34a ectopic expression on apoptosis of cisplatin-induce gastric cancer cell were determined by Annexin V/propidium iodide (PI) double staining method and flow cytometry. The effects of miR-34a ectopic expression on the AKT and p-AKT expression of cisplatin-induce gastric cancer cells were determined by Western blot and flow cytometry with the PI3K pathway inhibitor Wortmannin. As shown by qRT-PCR and Western blot analyses, the expression of miR-34a in cisplatin-resistant cell lines decreased significantly in comparison to that of SGC-7901 cell line (p?<?0.05), while significant up-regulation of survivin expression was also observed (p?<?0.05). Compared with the control group, the expression of miR-34a increased significantly in SGC-7901 cells transfected with miR-34a mimic for 48 h (p?<?0.01). After miR-34a inhibitor transfection, the expression of miR-34a decreased significantly (p?<?0.05). The viability of cisplatin-induce gastric cancer cells increased significantly (p?<?0.05) with significant decrease of apoptosis after miR-34a expression inhibition, as demonstrated by MTT and flow cytometry with miR-34a over-expression, the viability of cisplatin-induce gastric cancer cells decreased significantly (p?<?0.05), with significant apoptosis increase (p?<?0.05). As shown by Western blot and flow cytometry, in comparison to the control group, Wortmannin could inhibit miR-34a inhibitor and DDP induced up-regulation of p-AKT significantly (p?<?0.05) and stimulated apoptosis. In conclusion, miR-34a expression was down-regulated in cisplatin-resistant cell lines. miR-34a over-expression could improve the sensitivity of gastric cancer cells against cisplatin-based chemotherapies, with PI3K/AKT/survivin signaling pathway possibly involved in the mechanism.     

沉默ERK5对胃癌SGC-7901、BGC-823细胞生物学功能的影响

目的 探讨沉默细胞外信号调节激酶5（extracellular signal regulated kinase 5,ERK5）对胃癌细胞SGC-7901、BGC-823生物学功能的影响。方法 实时荧光定量PCR法（qRT-PCR）检测人胃癌细胞株和人胃黏膜上皮细胞株ERK5 mRNA的表达水平。应用短发荚RNA（shRNA）干扰技术沉默胃癌细胞SGC-7901、BGC-823中ERK5的表达。CCK-8法检测ERK5沉默后胃癌细胞的生长能力,平板克隆实验检测细胞克隆形成能力,Transwell 实验检测细胞侵袭和迁移能力,流式细胞仪检测细胞凋亡和周期分布。结果 与胃黏膜上皮细胞GES-1相比,胃癌细胞SGC-7901、BGC-823、AGS、HGC-27中ERK5 mRNA均呈高表达,相对表达量分别为2.696±0.501、1.865±0.185、1.793±0.137和1.530±0.093（P<0.05）。ERK5-shRNA有效沉默胃癌细胞SGC-7901、BGC-823中ERK5的表达水平,沉默效率分别为（74.4±1.5）%和（69.1±3.9）%,差异有统计学意义（P<0.05）。沉默 ERK5的表达能有效抑制胃癌细胞增殖、克隆形成、迁移和侵袭能力（P<0.05）,而促进胃癌细胞凋亡（P<0.05）,并诱导细胞周期阻滞于G0/G1期。结论 沉默ERK5可显著抑制胃癌细胞SGC-7901、BGC-823的生长侵袭,促进细胞凋亡,ERK5可能是胃癌治疗的潜在靶点。     

Down-regulation of miR-212 expression by DNA hypermethylation in human gastric cancer cells

There has been few report discussing the expression and function of miR-212 in gastric cancer (GC). The aim of this pilot study was to investigate the expression of miR-212 in both gastric cancer tissues and gastric cancer cells and further explores the possible reasons for this change and the impact on the development of gastric cancer. qRT-PCR was used to detect the expression of miR-212 in primary GC tissues, adjacent normal tissues, gastric cancer cell lines BGC-823, SGC-7901, MKN-45, and normal gastric mucosa cell line GES. The expression of miR-212 was evaluated before and after treatment with methylation inhibitor-5-Aza-2'-deoxycitidine (5-Aza-dC), finally anti-miRNA and dual luciferase reporter assay were used to prove that MYC is a target gene of miR-212. The results showed that a significant reduction of miR-212 expression in GC tissues was observed compared to that in normal tissues (P = 0.002). At the same time, miR-212 expression level in normal gastric mucosa cell line GES was higher than that of in gastric cancer cell lines BGC-823, SGC-7901, and MKN-45 (P = 0.015, 0.008, 0.044, respectively). Computer sequence analysis showed the hypermethylation of CpG islands(CPI) in the promoter regions of miR-212 led to the lower expression of miR-212 in gastric cell strains (BGC-823 and SGC-7901). MiR-212 expression was significantly recovered after treatment with methylation inhibitor 5-Aza-dC (P = 0.016, 0.000, 0.015, respectively). Then, the results of AMOs transfection and dual luciferase reporter assay showed that Myc is a target of miR-212, which will be helpful to verify the function of miR-212 in carcinogenesis. The conclusion could be deduced from the study that decreased expression of miR-212 may be due to hypermethylation of CPI in gastric cancer cells, and miR-212 might act on the progression of gastric cancer through the potential target gene Myc.     

Curcumin inhibits cell growth and induces cell apoptosis through upregulation of miR-33b in gastric cancer

In this work, the in vitro experiments about biological mechanisms of curcumin were conducted using the gastric cancer cell lines SGC-7901 and BGC-823. After 24-h exposure to curcumin at the concentrations of 5, 10, 15, 20, and 40 μmol/L, two cells showed the decreased proliferation and increased apoptosis abilities. Real-time PCR, Cell Counting Kit-8 (CCK-8) assay, western blotting, and cell apoptosis assay were used to further study the underlying mechanisms of curcumin. The first stage of our studies showed that curcumin affected the expression of miR-33b, which, in turn, affected the expression of the X-linked inhibitor of apoptosis protein (XIAP) messenger RNA (mRNA). Next, curcumin was also identified to regulate the proliferation and apoptosis of SGC-7901 and BGC-823 cells. Further bioinformatics analysis and luciferase reporter assays proved that XIAP was one of the target genes of miR-33b. In the next stage, SGC-7901 and BGC-823 cells were treated with 20 μL curcumin, miR-33b mimics, and small interfering RNA (siRNA) of XIAP, respectively. The results showed that curcumin had similar effects on cell growth and apoptosis as the upregulation of miR-33b and the upregulation of the siRNA of XIAP. The results that followed from the restore experiments showed that curcumin affected cell growth and apoptosis presumably by upregulating the XIAP targeting in gastric cancer. Collectively, our results indicate that curcumin-miR-33b-XIAP coupling might be an important mechanism by which curcumin induces the apoptosis of SGC-7901 and BGC-823 cells.

     

MicroRNA-6884-5p Regulates the Proliferation,Invasion, and EMT of Gastric Cancer Cells by Directly Targeting S100A16

S100 binding protein A16 (S100A16) expression levels are closely associated with microRNA (miRNA) processing. Higher levels of S100A16 are reported during the progression of many cancers. Our study mainly explored the interaction between S100A16 and miR-6884-5p in gastric cancer (GC). Quantitative real-time polymerase chain reaction (qRT-PCR) was used to determine the level of S100A16 and miR-6884-5p in GC tissues and cell lines. The si-S100A16, pcDNA-S100A16, miR-6884-5p mimic or inhibitor was transfected into GC cells, and the effects of S100A16 and miR-6884-5p on the proliferation, invasion, and epithelial–mesenchymal transition (EMT) were explored by qRT-PCR and Western blot assays. Luciferase assays were performed to validate S100A16 as an miR-6884-5p target in GC cells. In our study, we found that the level of miR-6884-5p was significantly decreased and the expression of S100A16 was significantly increased in GC tissues and cell lines. There was a close association between these changes. Knockdown of S100A16 significantly inhibited the proliferation, invasion, and EMT of GC cells. The bioinformatics analysis predicted that S100A16 is a potential target gene of miR-6884-5p, and the luciferase reporter assay confirmed that miR-6884-5p could directly target S100A16. Introduction of miR-6884-5p to GC cells had similar effects to S100A16 silencing. Overexpression of S100A16 in GC cells partially reversed the inhibitory effects of the miR-6884-5p mimic. miR-6884-5p inhibited the proliferation, invasion, and EMT of GC cells by directly decreasing S100A16 expression.     

HDAC5对胃癌SGC-7901细胞增殖和凋亡的影响

  目的   探讨HDAC5在胃癌细胞中的表达及其对胃癌SGC-7901细胞增殖和凋亡的影响。  方法   通过Western blot检测HDAC5和Twist1在胃癌细胞株及正常胃黏膜上皮细胞中的表达。使用MTT及流式细胞术分别检测HDAC5和Twist1对胃癌SGC-7901细胞增殖和凋亡的影响。  结果   HDAC5和Twist1在胃癌细胞株中的表达量均明显高于正常胃黏膜上皮细胞（P < 0.05）。沉默HDAC5的表达可使胃癌SGC-7901细胞中Twist1表达降低,并抑制其增殖、促进凋亡;而过表达HDAC5作用相反（P < 0.05）。此外,沉默Twist1可抑制SGC-7901细胞的增殖、促进其凋亡（P < 0.05）。  结论   HDAC5可能通过上调Twist1的表达水平促进胃癌细胞的增殖、抑制凋亡,从而促进胃癌的发生发展。      

胃癌组织中高表达的 miR-504 通过 TP53INP1 调控胃癌细胞 BGC-823 的生物学行为

目的：探究微小 RNA-504（miRNA-504）在胃癌（GC）组织中的表达水平及其对GC细胞生物学行为的调控机制。方法：收集2020年6月至2020年12月期间三亚中心医院外科收治的48例胃癌患者的肿瘤组织及癌旁组织标本,qPCR检测组织中 miR-504、肿瘤蛋白 53 诱导型核蛋白 1（tumor protein 53-induced nuclear protein 1,TP53INP1）mRNA 的水平 ,WB 法检测TP53INP1水平。体外培养人胃癌细胞 BGC-823,分为对照组（正常培养的 BGC-823细胞）、miR-504 mimic组、mimic-NC组、miR-504 inhibitor组、inhibitor-NC组、miR-504 inhibitor+si-NC组、miR-504 inhibitor+si-TP53INP1组,qPCR检测细胞中miR-504和TP53INP1 mRNA的表达,MTT法、流式细胞术、划痕实验和Transwell侵袭实验分别检测各组细胞的增殖、凋亡、迁移和侵袭能力,WB法检测各组细胞中增殖、迁移和侵袭相关蛋白（Cyclin D1、E-cadherin、MMP-2、MMP-9）以及TP53INP1的表达。双荧光素酶报告基因实验进一步验证miR-504与TP53INP1 mRNA的靶向关系。结果：与癌旁组织相比,胃癌组织中miR-504的表达显著升高（P<0.05）,而TP53INP1 mRNA 和蛋白表达水平显著降低（P<0.05 或P<0.01）,miR-504和TP53INP mRNA 两者的表达呈负相关（P<0.01）。与对照组相比,miR-504 mimic组BGC-823细胞中miR-504的表达显著升高（P<0.05）、TP53INP1 mRNA和蛋白的表达显著降低（均P<0.05）,且细胞增殖率、划痕愈合率、侵袭入Transwell小室下层的细胞数量,Cyclin D1、MMP-2、MMP-9蛋白表达均显著增加,细胞凋亡率和E-cadherin蛋白表达均显著降低（均P<0.05）。转染miR-504 inhibitor能显著下调BGC-823中miR-504的表达、上调TP53INP1 mRNA和蛋白的表达,抑制细胞的增殖、迁移与侵袭能力而促进细胞凋亡（均P<0.05）;而下调TP53INP1的表达可明显减弱miR-504下调对BGC-823细胞增殖、迁移与侵袭的抑制作用（P<0.01）。miR-504高表达能明显抑制野生型TP53INP1质粒的荧光素酶活性（P<0.05）。结论：miR-504在胃癌组织中呈高表达,下调miR-504可抑制胃癌BGC-823细胞的恶性生物学行为而促进其凋亡,其作用机制可能与靶向调控TP53INP1的表达有关。     

MicroRNA-181a Functions as an Oncomir in Gastric Cancer by Targeting the Tumour Suppressor Gene ATM

Based on our previous experiments, this study is to further investigate the functional significance of miR-181a and its target gene in gastric cancer. Expression of miR-181a was detected by qRT-PCR in three normal gastric tissues and three human gastric cancer cell lines (SGC-7901, MGC-803, and BGC-823 cells). After transfection with miR-181a inhibitor, proliferation, apoptosis, migration, and invasion of the SGC-7901 cells were evaluated. Ataxia-telangiectasia mutation (ATM) was predicted as a target gene of miR-181a with bioinformatics analysis, and was verified by lucifersae reporter assay. Expression of ATM protein in HEK293T cells and tissues was measured by Western Blot. Expression of ATM mRNA in HEK293T cells was measured by RT-PCR. Compared with three non-tumour tissues, the expression of miR-181a in three gastric cancer cells was significantly increased by 26.68, 14.83 and 14.96 folds; Compared with Negative Control(NC) and blank groups, transfection of miR-181a inhibitor led to inhibition of SGC7901 cell proliferation, invasion, and migration as well as promotion of apoptosis. A luciferase reporter assay demonstrated that ATM was a direct target of miR-181a, miR-181a mimics transfection down regulated ATM mRNA and protein expression. There was inverse correlation between miR-181a and ATM protein expression in gastric cancer and normal gastric tissues. Our study demonstrates that over-expression of miR-181a might be involved in development of gastric cancer by promoting proliferation and inhibiting apoptosis probably through directly targeting ATM. miR-181a modulation may be a potential strategy for the development of miRNA-based therapy of gastric cancer.     

MicroRNA-181a promotes gastric cancer by negatively regulating tumor suppressor KLF6

MicroRNAs have emerged as crucial regulators of tumorigenesis. However, it remains unknown whether miR-181a is involved in the pathogenesis of gastric cancer. In this study, we found that miR-181a is overexpressed in human gastric cancer tissues. Ectopic expression of miR-181a mimic promoted the proliferation, colony formation, migration, and invasion and inhibited the apoptosis of SGC-7901 gastric cancer cells, whereas ectopic expression of miR-181a inhibitor inhibited the malignant phenotypes of SGC-7901 cells. Site-directed mutagenesis and luciferase reporter assay demonstrated that miR-181a repressed KLF6 expression by targeting its 3??-UTR. Western blot analysis further showed that KLF6 protein was significantly decreased or increased when miR-181a mimic or inhibitor was transfected into SGC-7901 cells, respectively. In summary, these data suggest that KLF6 gene is a direct target of miR-181a and miR-181a functions as an oncomir in gastric cancer by repressing the expression of tumor suppressor KLF6.     

miR-325-3p靶向CLDN1基因调控胃癌上皮间质转化和侵袭转移

目的 探讨miR-325-3p靶向CLDN1基因对胃癌上皮间质转化和侵袭转移的影响。方法 选取人胃黏膜上皮细胞株GES-1以及人胃癌细胞株HGC27、SGC-7901、MKN-45和MGC-803,并检测细胞中miR-325-3p和CLDN1的表达。双荧光素酶报告实验验证miR-325-3p和CLDN1的靶向关系,干预胃癌细胞中miR-325-3p和CLDN1的表达,qRT-PCR和Western blot检测细胞中N-cadherin、Vimentin和MMP2的表达,CCK-8检测细胞增殖活力,Transwell和流式细胞仪分别检测细胞侵袭和凋亡能力。结果 相对于GES-1细胞,MGC-803细胞中miR-325-3p表达降低而CLDN1表达增高（均P<0.05）,双荧光素酶报告实验证实CLDN1为miR-325-3p的靶基因。过表达miR-325-3p能够抑制胃癌细胞的增殖、侵袭和上皮间质转化,促进胃癌细胞凋亡,抑制miR-325-3p则能够促进胃癌细胞的增殖、侵袭和上皮间质转化,抑制胃癌细胞凋亡（均P<0.05）。而过表达CLDN1则能够逆转miR-325-3p过表达对胃癌细胞生物学行为的影响。结论 miR-325-3p能够靶向抑制CLDN1进而抑制胃癌细胞的侵袭转移和上皮间质转化,促进胃癌细胞凋亡,miR-325-3p有望成为治疗胃癌的新靶点。     

长链非编码RNA CASC9在胃癌化疗耐药中的机制研究

目的:观察长链非编码RNA CASC9对胃癌（gastric cancer,GC）细胞增殖、凋亡以及对5-氟尿嘧啶（5-FU）化疗耐药的影响，并探讨其机制。方法:首先采用实时荧光聚合酶链反应法(real-time polymerase chain reaction,RT-PCR)检测永生化胃上皮细胞(GSE-1)和GC细胞(SGC-7901、BGC-823)中CASC9和P-gp的表达水平；在胃癌细胞SGC-7901和BGC-823中抑制CASC9表达后，通过RT-PCR检测P-gp的表达水平；在胃癌细胞SGC-7901中抑制CASC9表达后，再过表达P-gp，应用CCK-8法检测转染后各组光密度值以评价增殖率，应用Annexin V-APC单染色流式细胞术检测各组转染48 h后的细胞凋亡率，在培养基中加入不同浓度的5-FU检测各组细胞存活率。结果:与正常胃黏膜细胞相比，GC细胞中CASC9、P-gp过表达(P＜0.05)；抑制CASC9表达后胃癌细胞中P-gp表达下调(P＜0.05)；胃癌细胞抑制CASC9表达后细胞增殖转移能力明显减弱（P＜0.05），凋亡增加（P＜0.05），化疗耐药减弱（P＜0.05）；而过表达P-gp后恶性表型明显恢复（P＜0.05）。结论:CASC9可通过促进P-gp的表达调节GC细胞的增殖、凋亡和化疗耐药，参与GC的发生发展。     

Down-regulation of miR-212 expression by DNA hypermethylation in human gastric cancer cells

There has been few report discussing the expression and function of miR-212 in gastric cancer (GC). The aim of this pilot study was to investigate the expression of miR-212 in both gastric cancer tissues and gastric cancer cells and further explores the possible reasons for this change and the impact on the development of gastric cancer. qRT–PCR was used to detect the expression of miR-212 in primary GC tissues, adjacent normal tissues, gastric cancer cell lines BGC-823, SGC-7901, MKN-45, and normal gastric mucosa cell line GES. The expression of miR-212 was evaluated before and after treatment with methylation inhibitor-5-Aza-2′-deoxycitidine (5-Aza-dC), finally anti-miRNA and dual luciferase reporter assay were used to prove that MYC is a target gene of miR-212. The results showed that a significant reduction of miR-212 expression in GC tissues was observed compared to that in normal tissues (P = 0.002). At the same time, miR-212 expression level in normal gastric mucosa cell line GES was higher than that of in gastric cancer cell lines BGC-823, SGC-7901, and MKN-45 (P = 0.015, 0.008, 0.044, respectively). Computer sequence analysis showed the hypermethylation of CpG islands(CPI) in the promoter regions of miR-212 led to the lower expression of miR-212 in gastric cell strains (BGC-823 and SGC-7901). MiR-212 expression was significantly recovered after treatment with methylation inhibitor 5-Aza-dC (P = 0.016, 0.000, 0.015, respectively). Then, the results of AMOs transfection and dual luciferase reporter assay showed that Myc is a target of miR-212, which will be helpful to verify the function of miR-212 in carcinogenesis. The conclusion could be deduced from the study that decreased expression of miR-212 may be due to hypermethylation of CPI in gastric cancer cells, and miR-212 might act on the progression of gastric cancer through the potential target gene Myc.

     

miR-361-5p通过靶向CCND1逆转胃癌SGC-7901细胞奥沙利铂耐药性

目的：探讨miR-361-5p对胃癌SGC-7901细胞奥沙利铂（oxaliplatin,OXA）耐药性的影响及其作用机制。方法：采用qPCR法检测miR-361-5p在胃癌细胞MKN-45、MGC80-3、SGC-7901和OXA耐药细胞SGC-7901/OXA中的表达水平。利用脂质体转染技术分别将 miR-361-5p mimics/inhibitor、sh-CCND1 转染到 SGC-7901/OXA 细胞中 ,用 CCK-8 法和流式细胞术检测SGC-7901/OXA细胞的增殖、凋亡和细胞周期。用双荧光素酶报告基因实验验证miR-361-5p与CCND1的靶向关系,用WB法检测 CCND1 的表达水平。结果：miR-361-5p 在多种胃癌细胞和 SGC-7901/OXA 细胞中均低表达（P<0.05 或 P<0.01）。过表达miR-361-5p可显著促进SGC-7901/OXA细胞凋亡,诱导G0/G1细胞周期停滞并抑制细胞增殖（P<0.05或P<0.01）。双荧光素酶报告基因实验结果证实,miR-361-5p靶向负调控CCND1的表达（P<0.01）。敲减CCND1抑制SGC-7901/OXA细胞CCND1表达和细胞增殖,并诱导凋亡和G0/G1周期阻滞（P<0.05或P<0.01）。过表达miR-361-5p靶向下调CCND1进而促进SGC-7901/OXA细胞凋亡,诱导G0/G1细胞周期停滞并抑制细胞增殖（P<0.05或P<0.01）。结论：miR-361-5p过表达可逆转胃癌SGC-7901/OXA细胞对OXA的耐药性,其机制可能与靶向下调CCND1表达有关。     

Gli-1信号通路对TGF-β1诱导的人胃癌细胞上皮间质转化和侵袭的影响

目的:探讨核转录因子神经胶质瘤关联癌基因同源物1（glioma associated oncogene homolog 1,Gli-1）对转化生长因子-β1(transforming growth factor-β1,TGF-β1)诱导的人胃癌SGC-7901细胞发生上皮间质转化（epithelial-mesenchymal transition,EMT）的作用机制。方法:体外采用10 ng/ml TGF-β1对胃癌SGC-7901细胞进行处理,使用倒置显微镜观察细胞形态变化,RT-PCR和Western blot检测EMT上皮表型蛋白E-cadherin和间质表型蛋白Vimentin的表达水平;Transwell细胞侵袭实验检测细胞侵袭能力变化,检测TGF-β1 对SGC-7901细胞发生EMT 的影响;同时采用RT-PCR和Western blot检测Gli-1的mRNA和蛋白表达水平。随后进一步采用Gli-1基因特异性阻断剂GANT 61阻断Gli-1表达,并使用TGF-β1（10 ng/ml）对SGC-7901细胞进行处理,RT-PCR 和Western blot检测Gli-1、E-cadherin和Vimentin mRNA 及其蛋白表达水平的改变,并使用Transwell细胞侵袭实验检测阻断Gli-1对SGC-7901细胞侵袭能力的影响。结果:TGF-β1可以诱导人胃癌SGC-7901细胞发生上皮间质转化并促进细胞侵袭。TGF-β1可以在mRNA和蛋白水平下调上皮表型蛋白E-cadherin的表达、提高Gli-1和间质表型蛋白Vimentin的表达。TGF-β1可以明显提高SGC-7901细胞侵袭,而阻断Gli-1后可以抑制TGF-β1诱导的人胃癌SGC-7901细胞上皮间质转化和细胞侵袭。结论:胃癌SGC-7901细胞中Gli-1 可能参与TGF-β1 介导的EMT 的发生,Gli-1 可能作为胃癌基因治疗中的有效靶点发挥作用。     

miR-138-5p通过靶向TCF3实现对胃癌细胞SGC-7901侵袭和迁移的调控

目的:探讨miR-138-5p 与T细胞因子3 基因（T cell factor 3, TCF3）的靶向关系及其对人胃癌细胞SGC-7901 侵袭和迁移能力的影响。方法：miR-138-5p 模拟物转染SGC-7901 细胞后,实时荧光定量PCR（qRT-PCR）检测miR-138-5p 和TCF3 mRNA的相对表达;生物信息学方法预测miR-138-5p 与TCF3 基因的靶向匹配关系,采用荧光素酶报告基因系统鉴定该关系。miR-138-5p 转染正常胃癌细胞和TCF3 高表达胃癌细胞后,Western blotting 检测TCF3、神经钙黏蛋白（N-cadherin）、波形蛋白（Vimentin）、锌指转录因子（Slug）和上皮型钙黏蛋白（E-cadherin）的表达,Transwell 小室检测胃癌细胞侵袭能力,划痕实验检测细胞迁移能力。结果：miR-138-5p 过表达抑制TCF3 mRNA的表达;生物信息学软件预测显示miR-138-5p 与TCF3 mRNA有靶向结合区域,miR-138-5p mimic 降低TCF3 野生型质粒的荧光素酶活性,不影响TCF3 突变型质粒的荧光素酶活性。miR-138-5p 抑制TCF3 蛋白表达,miR-138-5p 减弱TCF3 过表达对SGC-7901 细胞侵袭和迁移能力的促进作用,同时其下调N-cadherin、Vimentin 和Slug 蛋白表达、上调E-cadherin 蛋白表达。结论：miR-138-5p 抑制胃癌细胞SGC-7901 的侵袭和迁移,与直接靶向调控TCF3 的表达有关。     

miR-138对人胃腺癌细胞SGC-7901增殖的影响

探讨microRNA-138（miR-138）对人胃癌SGC-7901细胞株增殖能力的影响及可能的机制。方法:采用阳离子脂质体Lipofectamine2000将miR-138 RNA转染人胃癌SGC-7901细胞株,采用荧光实时定量PCR检测miR-138表达丰度;采用流式细胞术检测转染后的细胞周期;采用MTT法检测细胞生长曲线;采用Western blotting检测人端粒酶逆转录酶（hTERT）蛋白的表达。结果:转染miR-138 RNA后,SGC-7901细胞内miR-138表达丰度升高,细胞增殖能力受到显著抑制,同时hTERT蛋白表达水平下调。结论:miR-138可抑制人SGC-7901细胞的增殖能力,机制可能是通过抑制靶基因hTERT蛋白的表达。      

异隐丹参酮对胃癌细胞增殖、周期和凋亡的影响

目的 探讨异隐丹参酮（ICTS）对胃癌BGC-823和SGC-7901细胞增殖、周期、凋亡的影响及可能机制。方法 体外培养胃癌细胞系BGC-823、SGC-7901,采用0、5、10、20 μmol／L ICTS处理24、48、72 h后, CCK-8法检测细胞的增殖抑制率;确定ICTS抑制BGC-823和SGC-7901细胞的最佳浓度和最佳作用时间后,流式细胞术检测其细胞周期和凋亡率。Western blotting检测ICTS处理后胃癌细胞中Cyclin D1、Bcl-2、p53、p21蛋白的表达。结果 0、5、10、20 μmol／L ICTS处理BGC-823细胞24 h的增殖抑制率分别为（0.789±0.048）％、（16.74±1.55）％、（33.58±2.26）％、（54.62±2.61）％,差异具有统计学意义（P＜0.05）;0、5、10、20 μmol／L ICTS 处理SGC-7901细胞24 h的增殖抑制率分别为（-0.184±0.023）％、（12.76±1.73）％、（32.95±2.47）％、（53.80±2.65）％,差异具有统计学意义（P＜0.05）。20 μmol／L ICTS 处理BGC-823细胞24、48、72 h的增殖抑制率分别为（54.62±2.61）％、（55.08±2.35）％、（59.72±2.53）％,差异无统计学意义（P＞0.05）;20 μmol／L ICTS 处理SGC-7901细胞24、48、72 h的增殖抑制率分别为（53.80±2.65）％、（55.76±2.47）％、（61.83±2.82）％,差异无统计学意义（P＞0.05）。20 μmol／L ICTS处理BGC-823、SGC-7901细胞24 h后G0／G1期细胞比例为（78.34±7.13）％和（79.57±7.34）％,均高于对照组,差异具有统计学意义（P＜0.05）。ICTS处理组BGC-823、SGC-7901凋亡率分别为（24.78±3.42）％和（28.76±4.21）％,均高于对照组,差异具有统计学意义（P＜0.05）。20 μmol／L ICTS处理BGC-823、SGC-7901细胞24 h后Cyclin D1和Bcl-2蛋白表达量均显著低于对照组,差异有统计学意义（P＜0.05）;p53和p21蛋白表达量显著高于对照组,差异有统计学意义（P＜0.05）。结论 ICTS通过增加p53、p21表达,降低Cyclin D1和Bcl-2表达,进而抑制细胞增殖,增加细胞G0／G1阻滞和凋亡,发挥抗胃癌的作用。