下调lncRNA MCF2L-AS1靶向miR-33b-5p抑制胃癌细胞增殖、迁移、侵袭并促进凋亡

摘要 目的：探讨lncRNA MCF2L-AS1对胃癌细胞恶性生物学行为的影响及分子机制。方法：选取45例胃癌患者的癌组织及癌旁正常组织,或培养胃黏膜上皮细胞GES-1、胃癌细胞HGC-27,采用RT-qPCR检测MCF2L-AS1和miR-33b-5p的表达水平。采用双荧光素酶报告实验检测MCF2L-AS1和miR-33b-5p的靶向关系。将HGC-27细胞分为si-NC组、si-MCF2L-AS1组、mimic NC组、miR-33b-5p mimic组、si-MCF2L-AS1+inhibitor NC组、si-MCF2L-AS1+miR-33b-5p inhibitor组,分别转染si-NC、si-MCF2L-AS1、mimic NC、miR-33b-5p mimic或共转染si-MCF2L-AS1+inhibitor NC、si-MCF2L-AS1+miR-33b-5p inhibitor。采用MTT实验检测细胞增殖情况,流式细胞术检测细胞凋亡率,克隆形成实验检测细胞克隆形成数,Transwell实验检测迁移和侵袭细胞数。结果：与癌旁正常组织或GES-1细胞相比,胃癌组织或HGC-27细胞中MCF2L-AS1表达水平升高、miR-33b-5p表达水平降低,差异均有统计学意义（P<0.05）。MCF2L-AS1可靶向调控miR-33b-5p。下调MCF2L-AS1或过表达miR-33b-5p,miR-33b-5p表达水平升高,HGC-27细胞凋亡率升高,但细胞增殖、克隆形成数、迁移和侵袭数均减少,差异均有统计学意义（P<0.05）。抑制miR-33b-5p可减弱下调MCF2L-AS1对HGC-27细胞的生物学作用。结论：下调MCF2L-AS1通过上调miR-33b-5p抑制胃癌细胞增殖、迁移、侵袭并促进凋亡;MCF2L-AS1通过靶向调控miR-33b-5p表达进而参与胃癌细胞的恶性生物学行为。     

过表达胃泌素促进胃癌细胞的增殖、迁移和侵袭

胃癌患者转移淋巴结中胃泌素基因的表达量是原发胃癌组织的42倍,推测胃泌素可能与胃癌转移密切相关. 本文通过构建含胃泌素基因的真核表达载体,成功获得过表达胃泌素的稳转胃癌细胞株AGS和SGC-7901, 并用MTT、细胞伤愈实验、Transwell 小室实验及ELISA检测过表达胃泌素对细胞迁移、侵袭及转移相关蛋白基质金属蛋白酶2（MMP-2）分泌能力的影响. 结果显示,过表达胃泌素稳转细胞的相对增殖率、 迁移入细胞致伤区的相对距离比对照组高,迁移和侵袭到Transwell下室面的细胞, 以及培养液中每mg蛋白质的MMP-2浓度也高于对照组的细胞. 结果提示,胃泌素通过促进胃癌细胞分泌MMP-2来增强细胞的迁移和侵袭能力. 该研究对揭示胃癌转移的分子机制具有重要意义.     

IFN-γ Induces Gastric Cancer Cell Proliferation and Metastasis Through Upregulation of Integrin β3-Mediated NF-κB Signaling

Interferon γ (IFN-γ), a multifunctional cytokine, was upregulated in the resected gastric cancer tissue. However, whether IFN-γ is involved in the regulation of gastric cancer has not been well elucidated. Herein, we aimed to investigate the effects and mechanism of IFN-γ on gastric cancer. In this study, we found a vital role of IFN-γ in enhancing proliferation, inhibiting apoptosis, and promoting cell migration and invasion in gastric cancer cells SGC-7901 and MGC-803. Additionally, IFN-γ activated nuclear factor κB (NF-κB) signaling pathway by upregulating the phosphorylation expression of p65 and IκBα, and induced the expression of integrin β3 in vitro. Therefore, to further investigate the relationship between IFN-γ and integrin β3, SGC-7901 cells were transfected with integrin β3 siRNA. And then cells expressed lower cell viability, migration, and invasion rates, while cell apoptosis was significantly enhanced. Meanwhile, expression of integrin β3, MMP-2, MMP-9, and NF-κB, including p65 and IκBα, and the nuclear translocation of NF-κB/p65 were dramatically repressed, whereas IFN-γ significantly improved the effects. Moreover, in vivo, the experiment of xenograft model and pulmonary metastasis model also retarded in integrin β3 siRNA group. And the expression of integrin β3, MMP-2, MMP-9, and NF-κB was repressed. However, the treatment with IFN-γ improved tumor volume, lung/total weight, tumor nodules, and the protein expression described above compared with integrin β3 siRNA group. Overall, the results indicated that IFN-γ induces gastric cancer cell proliferation and metastasis partially through the upregulation of integrin β3-mediated NF-κB signaling. Hence, the inhibition of IFN-γ or integrin β3 may be the key for the treatment of gastric cancer.     

G蛋白偶联胆汁酸受体1促进胃癌细胞的增殖、迁移和侵袭的实验研究

目的:探讨G蛋白偶联胆汁酸受体1(G-protein coupled bile acid receptor 1,GPBAR1/TGR5)对胃癌细胞增殖、迁移和侵袭的影响。方法:免疫组织化学染色方法(Immunohistochemistry,IHC)检测胃癌及癌旁组织芯片中TGR5表达情况;qRT-PCR及Western blot检测胃癌细胞系中TGR5表达水平;小干扰RNA处理AGS、MKN-45胃癌细胞后构建TGR5敲减细胞系,慢病毒载体转染胃癌SGC-7901细胞构建TGR5过表达细胞系;CCK-8实验、平板克隆形成实验、裸鼠皮下移植瘤实验检测TGR5对细胞增殖的影响;流式细胞仪检测TGR5对细胞周期及凋亡的影响;Tanswell实验检测TGR5对胃癌细胞迁移及侵袭的影响;Western blot检测上皮间充质转化(Epithelial-mesenchymal transition,EMT)相关分子β-连环蛋白(β-catenin)、锌脂蛋白转录因子(Snail)、E盒结合锌指蛋白(Zinc finger E-box binding homeobox 1,ZEB)1在AGS、MKN-45及SGC-7901胃癌细胞中的表达。结果:TGR5在胃癌及癌旁组织中均有表达,胃癌组织TGR5高表达率(41.0%)显著高于癌旁组织(9.5%),伴肠化生癌旁组织TGR5高表达率(50%)显著高于不伴肠化生的癌旁组织(0%),胃癌组织TGR5表达与肿瘤大小相关。TGR5在正常人胃上皮永生化细胞株GES-1及各胃癌细胞系中均有表达。TGR5表达敲低的AGS和MKN-45细胞增殖能力减弱、凋亡率显著升高、侵袭和迁移能力显著降低。过表达TGR5的SGC-7901细胞增殖能力增强、克隆形成能力提高、凋亡率明显减低、侵袭和迁移能力显著升高。此外,TGR5过表达显著上调了间质细胞标志物β-catenin、Snail、ZEB1的表达水平。结论:TGR5能够增强胃癌细胞增殖及迁移能力,并抑制细胞凋亡。TGR5可能通过EMT途径介导胃癌细胞转移。     

MicroRNA-137 Contributes to Dampened Tumorigenesis in Human Gastric Cancer by Targeting AKT2

MiRNAs play important roles in tumorigenesis. This study focused on exploring the effects and regulation mechanism of miRNA-137 on the biological behaviors of gastric cancer. Total RNA was extracted from tissues of 100 patients with gastric cancer and from four gastric cancer cell lines. Expression of miR-137 was detected by real-time PCR from 100 patients. The effects of miR-137 overexpression on gastric cancer cells’ proliferation, apoptosis, migration and invasion ability were investigated in vitro and in vivo. The target gene of miR-137 was predicted by Targetscan on line software, screened by dual luciferase reporter gene assay and demonstrated by western blot. As a result, the expression of miR-137 was significant reduced in gastric cancer cell line HGC-27, HGC-803, SGC-7901 and MKN-45 as well as in gastric cancer tissues compared with GES-1 cell or matched adjacent non-neoplastic tissues (p<0.001). The re-introduction of miR-137 into gastric cancer cells was able to inhibit cell proliferation, migration and invasion. The in vivo experiments demonstrated that the miR-137 overexpression can reduce the gastric cancer cell proliferation and metastasis. Bioinformatic and western blot analysis indicated that the miR-137 acted as tumor suppressor roles on gastric cancer cells through targeting AKT2 and further affecting the Bad and GSK-3β. In conclusion, the miR-137 which is frequently down-regulated in gastric cancer is potentially involved in gastric cancer tumorigenesis and metastasis by regulating AKT2 related signal pathways.     

下调UCA1通过靶向miR-23b及其下游靶基因抑制胃癌细胞的增殖和转移

摘要 目的：探讨长链非编码RNA尿路上皮癌相关基因1（UCA1）调控胃癌细胞增殖和转移的分子机制。方法：将人胃癌细胞株SGC7901分为：对照组、siRNA-NC组、siRNA-UCA1组、inhibitor-NC组和miR-inhibitor组、si-UCA1+inhibitor-NC组和si-UCA1+miR-inhibitor组。对SGC7901细胞分别转染siRNA-UCA1及阴性对照（siRNA-NC）、miR-inhibitor及阴性对照（inhibitor-NC）,未转染的细胞作为对照组。通过RT-qPCR检测细胞中UCA1和miR-23b-3p的水平。通过CCK-8法、伤口愈合实验和Transwell实验评价细胞的增殖、迁移和侵袭能力。通过Western blot分析细胞中IL6R、BCL2和HSP90B1蛋白的表达。使用pcDNA-UCA1/pcDNA-NC与pGL3-miR-23b-3p-WT/pGL3-miR-23b-3p-Mut共转染细胞,通过双荧光素酶报告实验验证UCA1与miR-23b-3p的靶向关系。结果：细胞培养48 h和72 h后,与对照组比较,siRNA-UCA1组的细胞活力分别降低了31.58%和31.40%（P<0.05）。与对照组比较,siRNA-UCA1组的细胞迁移率[(61.46±5.43)% vs (23.16±3.17)%]、侵袭细胞数量（109.17±9.66 vs 50.83±6.96）、IL6R、BCL2和HSP90B1的蛋白相对表达量均显著降低,而miR-23b-3p相对表达量升高（P<0.05）。与pGL3-miR-23b-3p-WT共转染后,与pcDNA-NC组比较,pcDNA-UCA1组的相对荧光酶活性降低了66.12%（P<0.05）。与si-UCA1+inhibitor-NC组比较,si-UCA1+miR-inhibitor组的细胞活力、细胞迁移率、侵袭细胞数量、IL6R、BCL2和HSP90B1的蛋白相对表达量均显著升高（P<0.05）。结论：下调UCA1通过靶向miR-23b-3p及其下游基因IL6R、BCL2和HSP90B1来抑制胃癌细胞的增殖和转移。     

LncRNA CRNDE promotes cell proliferation,migration and invasion of ovarian cancer via miR-423-5p/FSCN1 axis

Ovarian cancer seriously threatens the health of women. LncRNA CRNDE is known to be upregulated in ovarian cancer. However, the mechanism by which CRNDE regulates the progress of ovarian cancer is largely unknown. MTT assay was applied to measure the cell viability. Colony formation assay was used to measure the cell proliferation. Cell migration was tested by wound healing, and Transwell assay was performed to detect cell invasion. In addition, the expression of miR-423-5p, CRNDE and FSCN1 were detected by RT-qPCR and western blotting, respectively. Meanwhile, dual-luciferase reporter assay and RIP assay were performed to explore the correlation between miR-423-5p and CRNDE (or FSCN1). CRNDE and FSCN1 were upregulated in ovarian cancer cells (SKOV3, CAOV-3, IGROV1, A2780 and C13K), while miR-423-5p was downregulated. Moreover, silencing of FSCN1/CRNDE significantly decreased proliferation, migration and invasion of ovarian cancer cells (SKOV3 and CI3K) via suppressing MMP-2 and MMP-9. In addition, CRNDE could sponge miR-423-5p, and FSCN1 was confirmed to be the direct target of miR-423-5p. Furthermore, CRNDE knockdown-induced inhibition of FSCN1 was notably reversed by miR-423-5p downregulation. Knockdown of CRNDE inhibited cell proliferation, migration and invasion of ovarian cancer via miR-423-5p/FSCN1 axis. Thus, CRNDE may serve a new target for ovarian cancer.

     

Epigenetic Silencing of miR-338-3p Contributes to Tumorigenicity in Gastric Cancer by Targeting SSX2IP

MicroRNA has been recently recognized as playing a prominent role in tumorigenesis and metastasis. Here, we report that miR-338-3p was epigenetically silenced in gastric cancer, and its down-regulation was significantly correlated with gastric cancer clinicopathological features. Strikingly, restoring miR-338-3p expression in SGC-7901 gastric cancer cells inhibited proliferation, migration, invasion and tumorigenicity in vitro and in vivo, at least partly through inducing apoptosis. Furthermore, we demonstrate the oncogene SSX2IP is a target of miR-338-3p. We propose that miR-338-3p functions as a tumor suppressor in gastric cancer, and the methylation status of its CpG island could serve as a potential diagnostic marker for gastric cancer.     

MiR-9-3p regulates the biological functions and drug resistance of gemcitabine-treated breast cancer cells and affects tumor growth through targeting MTDH

This study explored the role of MTDH in regulating the sensitivity of breast cancer cell lines to gemcitabine (Gem) and the potential miRNAs targeting MTDH. The expression of MTDH in cancer tissues and cells was detected by immunohistochemical staining or qRT-PCR. The target genes for MTDH were predicted by bioinformatics and further confirmed by dual-luciferase reporter assay and qRT-PCR. Cancer cells were transfected with siMTDH, MTDH, miR-9-3p inhibitor, or mimics and treated by Gem, then CCK-8, colony formation assay, tube formation assay, flow cytometry, wound healing assay, and Transwell were performed to explore the effects of MTDH, miR-9-3p, and Gem on cancer cell growth, apoptosis, migration, and invasion. Expressions of VEGF, p53, cleaved caspase-3, MMP-2, MMP-9, E-Cadherin, N-Cadherin, and Vimentin were determined by Western blot. MTDH was high-expressed in cancer tissues and cells, and the cells with high-expressed MTDH were less sensitive to Gem, while silencing MTDH expression significantly promoted the effect of Gem on inducing apoptosis, inhibiting cell migration, invasion, and growth, and on regulating protein expressions of cancer cells. Moreover, miR-9-3p had a targeted binding relationship with MTDH, and overexpressed miR-9-3p greatly promoted the toxic effects of Gem on cancer cells and expressions of apoptosis-related proteins, whereas overexpressed MTDH partially reversed such effects of overexpressed miR-9-3p. The study proved that miR-9-3p regulates biological functions, drug resistance, and the growth of Gem-treated breast cancer cells through targeting MTDH.Subject terms: Cancer, Cell biology     

Upregulation of periostin prevents P53-mediated apoptosis in SGC-7901 gastric cancer cells

Periostin is frequently upregulated in human cancers including gastric cancer and implicated in cancer cell proliferation, invasion, and epithelial–mesenchymal transition. This study was undertaken to investigate the effects of periostin overexpression on the chemosensitivity of gastric cancer cells. We constructed a stable cell line overexpressing periostin in SGC-7901 human gastric cancer cells. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay revealed that periostin had no influence on the proliferation of SGC-7901 cells. Compared to empty vector-transfected cells, overexpression of periostin rendered SGC-7901 cells more resistant to cisplatin or 5-fluorouracil (5-FU)-induced apoptosis, accompanying with less release of cytochrome c from mitochondria and diminished cleavage of caspase-3 and poly (ADP-ribose) polymerase. Periostin-overexpressing cells treated with cisplatin or 5-FU showed significantly (p < 0.05) decreased expression of Bax and p53 proteins and increased expression of Bcl-2 protein, when compared to drug-treated mock counterparts. Restoration of p53 expression by delivering wild-type p53 gene resulted in a marked increase in drug-induced apoptosis in periostin-overexpressing SGC-7901 cells. Periostin overexpression elevated the phosphorylation of Akt. Pretreatment of periostin-overexpressing cells with an Akt inhibitor, MK-2206, partially rescued periostin-mediated inhibition of p53 expression and drug resistance. Taken together, our data indicate that periostin confers protection against cisplatin or 5-FU-induced apoptosis in SGC-7901 cells, likely through modulating the Akt/p53 pathway, and thus represents a potential therapeutic target in gastric cancer.     

DNA methylation and miR-92a-3p-mediated repression of HIP1R promotes pancreatic cancer progression by activating the PI3K/AKT pathway

Pancreatic cancer (PAAD) is a highly malignant tumour characterized of high mortality and poor prognosis. Huntingtin-interacting protein 1-related (HIP1R) has been recognized as a tumour suppressor in gastric cancer, while its biological function in PAAD remains to be elucidated. In this study, we reported the downregulation of HIP1R in PAAD tissues and cell lines, and the overexpression of HIP1R suppressed the proliferation, migration and invasion of PAAD cells, while silencing HIP1R showed the opposite effects. DNA methylation analysis revealed that the promoter region of HIP1R was heavily methylated in PAAD cell lines when compared to the normal pancreatic duct epithelial cells. A DNA methylation inhibitor 5-AZA increased the expression of HIP1R in PAAD cells. 5-AZA treatment also inhibited the proliferation, migration and invasion, and induced apoptosis in PAAD cell lines, which could be attenuated by HIP1R silencing. We further demonstrated that HIP1R was negatively regulated by miR-92a-3p, which modulates the malignant phenotype of PAAD cells in vitro and the tumorigenesis in vivo. The miR-92a-3p/HIP1R axis could regulate PI3K/AKT pathway in PAAD cells. Taken together, our data suggest that targeting DNA methylation and miR-92a-3p-mediated repression of HIP1R could serve as novel therapeutic strategies for PAAD treatment.     

白藜芦醇通过Pi3K/AKT 通路抑制胃癌SGC-7901 细胞增殖和迁移

目的:验证白藜芦醇是否可以抑制胃癌SGC-7901细胞增殖和迁移及其信号通路。方法:用不同浓度白藜芦醇干预SGC-7901细胞,再用LY-294002和IGF-1分别用来抑制和激活Pi3K/AKT通路。MTT法测细胞增殖,划痕试验和Transwell试验测细胞迁移,Western blot检测细胞迁移相关蛋白(MMP-2、MMP-9)、细胞迁移相关蛋白(P21、P27)、以及AKT、p-AKT的表达情况;结果:相比于对照组,白藜芦醇组胃癌细胞增殖和迁移减弱(P=0.001),p-AKT表达减少(P0.001);LY-294002可以抑制p-AKT的表达(P=0.004),和白藜芦醇一样可以抑制胃癌细胞的增殖和迁移;IGF-1可以显著增加p-AKT的表达(P0.001),可以逆转白藜芦醇对胃癌细胞增殖和迁移的抑制作用。结论:白藜芦醇通过抑制Pi3K/AKT信号通路抑制胃癌细胞增殖和迁移。     

miR-670-5p对肺癌细胞增殖、迁移、侵袭的影响

目的: 探讨miR-670-5p对肺癌细胞增殖、迁移和侵袭的影响,分析其调控WW结构域氧化还原酶基因(WWOX)的机制。方法: 收集2016年1月至2017年10月收治的28例肺癌组织和对应癌旁组织,实时荧光定量PCR(RT-qPCR)检测肺癌组织、癌旁组织中miR-670-5p的表达水平。将肺癌细胞A549分为anti-miR-NC组(转染anti-miR-NC)、anti-miR-670-5p组(转染anti-miR-670-5p)、anti-miR-670-5p+si-NC组(转染anti-miR-670-5p与si-NC)、anti-miR-670-5p+si-WWOX组(转染anti-miR-670-5p与si-WWOX)。转染48 h后,RT-qPCR或蛋白质印记(Western blot)检测转染效果。细胞计数试剂盒(CCK-8)检测细胞活力;Transwell实验检测细胞迁移和侵袭能力;Western blot检测P21、上皮细胞钙粘蛋白(E-cadherin)和基质金属蛋白酶2(MMP-2)蛋白的表达水平。双荧光素酶报告基因实验和Western blot验证miR-670-5p和WWOX的靶向关系。结果: 肺癌组织中miR-670-5p的表达水平较癌旁组织显著升高(P＜0.05)。抑制miR-670-5p可抑制MMP-2蛋白表达(P＜0.05),促进P21和E-cadherin表达(P＜0.05),抑制A549细胞增殖、迁移和侵袭(P＜0.05)。WWOX是miR-670-5p的靶基因,miR-670-5p负调控WWOX表达。抑制WWOX可部分逆转anti-miR-670-5p对A549细胞增殖、迁移和侵袭的影响(P＜0.05)。结论: miR-670-5p通过靶向WWOX能够促进肺癌细胞增殖、迁移、侵袭。     

LncRNA H19 regulates smooth muscle cell functions and participates in the development of aortic dissection through sponging miR-193b-3p

Background: Multiple studies showed that long-chain noncoding RNA H19 (LncRNA H19) is high-expressed in human and mouse abdominal aortic aneurysms (AAAs). We speculated that it plays an important role in arterial disease, and therefore studied the role and mechanism of H19 in aortic dissection (AD).Methods: The expressions of related genes in human aortic smooth muscle cells (HASMCs) induced by platelet-derived growth factor BB (PDGF-BB) or in the aortic tissue of AD patients/mice were identified by Western blot and quantitative real-time polymerase chain reaction. The targeting relationship between H19 and miR-193b-3p was predicted and verified by bioinformatics analysis, dual luciferase assay, RNA pull-down assay, RNA immunoprecipitation (RIP), and Pearson correlation coefficient. The H19 and miR-193b-3p effects on the biological functions of tissues and cells were examined by MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide, thiazolyl blue tetrazolium bromide) assay, wound-healing assay, and Hematoxylin–Eosin (HE) staining.Results: LncRNA H19 was abnormally high-expressed in thoracic aorta tissues of AD patients, and it could competitively bind to and inhibit miR-193b-3p. In the PDGF-BB group, the expressions of H19, matrix metallopeptidase (MMP) 2 (MMP-2) and MMP-9 were up-regulated and the expressions of miR-193b-3p, α-SMA, and SM22α were down-regulated; moreover, the proliferation and migration rate of HASMCs were increased. However, H19 silencing reversed the regulation of PDGF-BB on HASMCs. More interestingly, miR-193b-3p inhibitor could partially reverse the effect of H19 silencing. In addition, the above results were verified by animal experiments, showing that shH19 and up-regulated miR-193b-3p could significantly reduce the thoracic aorta pathological damage in AD mice.Conclusion: LncRNA H19 regulated smooth muscle cell function by sponging miR-193b-3p and it participated in the development of AD.     

miR-216b-5p靶向调控BTN3A2促进胶质瘤细胞LN-229的迁移以及侵袭能力

大量证据表明microRNA（miRNA）通过靶向调控靶基因的表达从而在肿瘤侵袭与转移中发挥重要作用。然而关于microRNA-216b-5p (miR-216b-5p )通过靶向嗜乳脂蛋白第3亚家族膜蛋白A2（butyrophilin subfamily 3 member A2,BTN3A2）促进胶质瘤侵袭与转移的机制尚不明确。本研究通过GSE15824与GSE4290差异表达分析筛选出同时在2个芯片中表达上调的BTN3A2（P＜0.05）。生存曲线结果显示,高表达BTN3A2病人总生存期明显下降（P＜0.001）。表达量分析结果显示,BTN3A2表达随WHO分级升高而升高（P＜0.05）,同时1p/19q未联合缺失与IDH突变型病人BTN3A2表达升高（P＜0.001）。基因集富集分析（gene set enrichment analysis,GSEA）结果显示,BTN3A2与众多癌症相关通路有关（P＜0.05）;Western印迹结果显示,BTN3A2在7例胶质瘤组织和胶质瘤细胞系U87、U251和LN-229中表达上调,过表达miR-216b-5p （miR-216b-5p mimics）后BTN3A2蛋白表达水平降低;Transwell结果显示,转染BTN3A2干扰质粒（si-BTN3A2）和miR-216b-5p mimics后可以抑制LN 229细胞体外迁移与侵袭能力（P＜0.05）;在线预测网站证实,miR-216b-5p 为BTN3A2潜在靶基因;生存曲线结果显示,与低表达miR-216b-5p 病人相比,高表达病人生存率明显上调（P=0.025）;荧光定量RT PCR结果显示,miR-216b-5p 在胶质瘤U87、U251和LN-229细胞中表达下降（P＜0.05）;双荧光素酶结果显示,BTN3A2存在与miR-216b-5p 的结合靶点(P<005);综上所述,BTN3A2可能通过结合miR-216b-5p 促进胶质瘤细胞LN 229的迁移以及侵袭。     

Inhibitory effects of γ-tocotrienol on invasion and metastasis of human gastric adenocarcinoma SGC-7901 cells

Natural vitamin E is a mixture of two classes of compounds, tocopherols and tocotrienols. Recent research has revealed that tocotrienols, especially γ-tocotrienol, exhibit not only the same antioxidant ability as tocopherols, but also remarkable anticancer capacity in cancer cell lines. In this study, the invasion and metastatic capacities of gastric adenocarcinoma SGC-7901 cells and the correlation with antimetastasis mechanisms induced by γ-tocotrienol were explored. The results showed the inhibitory effects of γ-tocotrienol at doses of 15, 30, 45 and 60 μmol/L for 48 h on cell migration and cell matrigel invasion; activities of matrix metalloproteinase (MMPs) increased in SGC-7901 cells when compared to the control group (P<.05 or P<.01). An increasing trend in the chemotactic responses to fibronectin (FN) in SGC-7901 cells was found in the γ-tocotrienol treatments. SGC-7901 cell attachment decreased in the γ-tocotrienol-treated groups in comparison with the control group (P<.01). The mRNA expressions of MMP-2 and MMP-9 showed that γ-tocotrienol significantly reduced the matrigel invasion capability through down-regulation of the mRNA expressions of MMP-2 and MMP-9 (P<.01), and up-regulation of tissue inhibitor of metalloproteinase-1 (TIMP-1) and TIMP-2 in SGC-7901 cells by treatment with γ-tocotrienol for 48 h (P<.05). γ-Tocotrienol also significantly increased the mRNA expression of nm23-H1 in SGC-7901 cells (P<.01). These findings suggest a potential mechanism of γ-tocotrienol-mediated antitumor metastasis activity and indicate the role of vitamin E as potential chemopreventative agents against gastric cancer.     

CRKL promotes cell proliferation in gastric cancer and is negatively regulated by miR-126

V-crk avian sarcoma virus CT10 oncogene homolog-like (CRKL) is a member of CRK family and act as an adaptor protein participating in intra-cellular signal transduction. The role of CRKL in gastric cancer (GC) remains unclear. In this study, we show that CRKL was aberrantly highly expressed in both GC tumor specimens and cell lines (SGC-7901, MKN-45, MKN-28 and SUN-16). The expression of CRKL was significantly correlated with GC clinicopathologic features including tumor size, local invasion, lymph node metastasis and TNM stages. Knock-down of CRKL in SGC-7901 cells induced a suppression of cell proliferation along with a significant arrest of cell cycle in G0/G1 phase, however, no significant influence was observed on cell apoptosis. We validate that miR-126, a suppressor in GC, was a negative regulator of CRKL by directly combining with the 3′ untranslated region of CRKL mRNA, and over-expression of miR-126 inhibited the protein expression of CRKL significantly. These results suggest that CRKL may function as an oncogene in GC by promoting the GC cell proliferation, which provides us a likely biomarker and a potential target for GC prevention, diagnosis and therapeutic treatment. Moreover, the targeting relationship between CRKL and miR-126 partly reveals the mechanism of miR-126 on GC suppression.