CircCCND1调节miR-340-5p/TGIF1轴对H446肺癌细胞恶性生物学行为的影响

背景与目的 肺癌是常见的肺部恶性肿瘤,探究肺癌发生发展的分子机制是当前研究的热点。环状RNA细胞周期蛋白D1 (circular RNA Cyclin D1,CircCCND1)在肺癌中高表达,可能是治疗肺癌的潜在靶点。本研究旨在探讨CircCCND1调节miR-340-5p/转化生长因子β诱导因子同源框1 (transforming growth factor β-induced factor homeobox 1,TGIF1)轴对肺癌细胞恶性生物学行为的影响。方法 检测人正常肺上皮细胞BEAS-2B及人肺癌H446细胞中CircCCND1、miR-340-5p及TGIF1 mRNA表达。将体外培养的H446细胞分为对照组、CircCCND1 siRNA组、miR-340-5p mimics组、阴性对照组、CircCCND1 siRNA+miR-340-5p inhibitor组,检测细胞增殖、线粒体膜电位、凋亡、迁移和侵袭情况,以及各组细胞CircCCND1、miR-340-5p、TGIF1 mRNA、BCL2相关X蛋白(BCL2-associated X protein,Bax)、剪切的半胱天冬氨酸蛋白酶3 (cleaved Caspase-3)、N-钙黏蛋白(N-cadherin)、E-钙黏蛋白(E-cadherin)、TGIF1蛋白表达,并验证miR-340-5p与CircCCND1、TGIF1的靶向关系。结果 与BEAS-2B细胞相比,H446细胞CircCCND1、TGIF1 mRNA升高,miR-340-5p表达降低(P<0.05)。敲低CircCCND1或上调miR-340-5p表达可抑制H446细胞增殖、迁移、侵袭,降低TGIF1 mRNA和TGIF1蛋白表达,促进细胞凋亡;下调miR-340-5p可拮抗敲低CircCCND1对H446肺癌细胞恶性生物学行为的抑制作用。CircCCND1可能靶向下调miR-340-5p,miR-340-5p可能靶向下调TGIF1。结论 敲低CircCCND1可抑制肺癌H446细胞恶性行为,其作用可能是通过调控miR-340-5p/TGIF1轴实现的。

TGIF1在红细胞分化中的功能和机制研究

目的筛选潜在的促红系分化因子,并验证其对红系分化的促进作用,探讨促分化机制。方法首先通过对高通量组学测序数据的分析,找到潜在红系调控转录因子;之后在红系分化的细胞模型TF-1细胞系中干扰该因子的表达,观察该因子的异常表达对红系分化的影响;进一步对目的基因敲低的细胞系进行转录组测序,同时利用生物信息学的手段分析受影响的红系相关因子以及通路。结果高通量组学测序分析得到潜在促红系分化调控因子TGIF1。TGIF1敲低细胞中,ε-珠蛋白、γ-珠蛋白、红系特异转录因子(GATA1、KLF1)、以及红系细胞表面特异糖蛋白标志分子CD235a的m RNA表达量及血红蛋白浓度均低于对照组。TGIF1过表达细胞的γ-珠蛋白m RNA高于对照组;促红细胞生成素诱导3天后,TGIF1过表达细胞表面CD235a的表达高于空白细胞组。进一步对稳定敲低TGIF1的TF-1细胞系进行高通量转录组测序分析,发现Smad复合物和相关靶基因表达上调,而GATA1和ALAS2的表达量则降低。结论 TGIF1是一个促红系分化的转录调控因子,可能通过影响转化生长因子β(transforming growth factor-β,TGFβ)通路中Smad复合物和相关靶基因的表达,或通过影响GATA1和ALAS2的表达来调控红系分化过程。

TGIF1表达水平对乳腺癌细胞上皮型钙黏附蛋白和Twist1蛋白表达的影响

目的:观察转化生长因子β-同源诱导因子1(TGIF1)表达水平对乳腺癌细胞上皮型钙黏附蛋白(E-cadherin)和人Twist相关蛋白1(Twist1)表达的影响。方法:24只6周龄SPF级Balb/c雌性小鼠随机分为对照组、TGIF1沉默组、TGIF1正常组和TGIF1过表达组,TGIF沉默组小鼠给予慢病毒颗粒TGIF shRNA (h) lentiviral particles(sc-36,659-V)干扰的4T1乳腺癌细胞构建乳腺癌小鼠模型,TGIF1正常组小鼠采用乳腺癌细胞(4T1)构建乳腺癌小鼠模型,TGIF1过表达组采用TGIF1过表达的4T1乳腺癌细胞建立乳腺癌小鼠模型,测定各组小鼠乳腺肿瘤组织中TGIF1、E-cadherin和Twist1蛋白水平。结果:TGIF1过表达组小鼠肿瘤体积明显大于TGIF1正常组和沉默组,组间差异比较有统计学意义(P<0.05);TGIF1正常组、TGIF1沉默组、TGIF1过表达组TGIF1和Twist1蛋白表达水平明显高于对照组,E-cadherin明显低于对照组,组间差异比较有统计学意义(P<0.05);TGIF1沉默组TGIF1和Twist1蛋白表达水平明显低于TGIF1正常组,E-cadherin明显高于TGIF1正常组,组间差异比较有统计学意义(P<0.05);TGIF1过表达组TGIF1和Twist1蛋白表达水平明显高于TGIF1正常组,E-cadherin明显低于TGIF1正常组,组间差异比较有统计学意义(P<0.05);Pearson相关性分析结果显示,乳腺癌组织TGIF1表达水平与E-cadherin蛋白表达水平呈明显负相关,与Twist1蛋白水平呈明显正相关(P<0.05)。结论:TGIF1可通过调控E-cadherin和Twist1干预EMT途径从而影响乳腺癌的转移和侵袭,值得进一步研究。

NH4Cl promotes apoptosis and inflammation in bovine mammary epithelial cells via the circ02771/miR-194b/TGIF1 axis

Excess ammonia(NH_(3))in the circulation of dairy animals can reduce animal health and the quality of products for human consumption.To develop effective prevention and treatment methods,it is essential to examine the molecular mechanisms through which excess NH_(3) may affect the mammary gland.The present study used bovine mammary epithelial cells(BMECs)to evaluate the effects of exogenous NH_(4)Cl on the abundance of circular RNAs(circRNAs)using high-throughput sequencing.Among the identified circRNAs,circ02771 was the most significantly upregulated by exogenous NH_(4)Cl(P<0.05),with a fold change of 4.12.The results of the apoptosis and proliferation assays,transmission electron microscopy,H&E staining,and immunohistochemistry revealed that circ02771 increased apoptosis and inflammation.A double luciferase reporter assay revealed that circ02771 targeted miR-194b,and the overexpression of circ02771(pcDNA-circ02771)reduced(P<0.05)the expression of miR-194b and led to apoptosis and inflammation.Circ02771 also enhanced the expression of transforming growth factor beta-induced factor homeobox 1(TGIF1),which is a target gene of miR-194b.Overall,this study suggests that the circ02771/miR-194b/TGIF1 axis plays a role in mediating the effects of NH_(4)Cl on BMECs.Therefore,this axis provides a novel target to help control hazards within the mammary gland from high circulating NH_(4)Cl levels.

Effect of TGIF1 expression on epithelial cadherin and Twist1 protein expression in breast cancer cells

Objective: To observe the effect of the expression of transforming growth factor β-homologous inducible factor 1 (TGIF1) on the expression of epithelial cadherin (E-cadherin) and human Twist-related protein 1 (Twist1) in breast cancer cells. Methods: Total of twenty-four 6-week-old female SPF Balb/c mice were randomly divided into a control group, a TGIF1-silencing group, a TGIF1-normal group, and a TGIF1-overexpression group. In the TGIF1-silencing group, 4T1 breast cancer cells were interfered by lentivirus shRNA (H) lentiviral particles (sc-36659-v) to construct a breast cancer model. TGIF1-normal group used breast cancer cells (4T1) to construct a mouse model of breast cancer. And the TGIF1-overexpression group used 4T1 breast cancer cells with TGIF1 overexpression to establish a mouse model of breast cancer. Determination of TGIF1, E-cadherin and Twist1 protein levels in breast tumor tissue of mice in each group. Results: The tumor volume of mice in the TGIF1-overexpression group was significantly larger than that in the TGIF1-normal group and the TGIF1-silencing group, and the differences between the groups were statistically significant (P <0.05).The expression levels of TGIF1 and Twist1 protein in TGIF1-normal group, TGIF1-silencing group, and TGIF1-overexpression group were significantly higher than those in control group, and E-cadherin was significantly lower than that in control group. The differences between groups were statistically significant (P <0.05).The expression level of TGIF1 and Twist1 protein in TGIF1-silencing group was significantly lower than that in TGIF1-normal group, and E-cadherin was significantly higher than that in TGIF1-normal group (P < 0.05).The expression levels of TGIF1 and Twist1 proteins in the TGIF1-overexpression group were significantly higher than those in the TGIF1-normal group, and E-cadherin was significantly lower than that in the TGIF1-normal group. The differences between the groups were statistically significant (P <0.05). Pearson correlation analysis showed that the expression level of TGIF1 in breast cancer tissue was significantly negatively correlated with the expression level of E-cadherin protein, and was significantly positively correlated with the level of Twist1 protein (P <0.05). Conclusion: TGIF1 can affect the metastasis and invasion of breast cancer by regulating E-cadherin and Twist1 to interfere with the EMT pathway, which deserves further study.

circ_0001429靶向miR-139-5p/TGIF1分子轴调控膀胱癌T24细胞恶行生物学行为

目的:探究circ0001429通过调控miR-139-5p/转录生长因子影响因子1(TGF-interacting factor 1,TGIF1)分子轴对膀胱癌T24细胞恶性生物学行为的影响。方法:采用q PCR实验检测circ0001429在膀胱癌细胞系SW780、T24、5637和人膀胱上皮永生化细胞SV-HUC-1中的表达水平,双荧光素酶报告基因实验验证miR-139-5p、circ0001429与TGIF1之间的靶向调控关系;将T24细胞分为NC组、sh-circ0001429组、miR-139-5p mimics组、sh-TGIF1组、pcDNA-circ0001429+sh-TGIF1组、miR-139-5p mimics+pcDNA-TGIF1组以及sh-circ0001429+miR-139-5p inhibitor组,Western blotting检测各组细胞中TGIF1的表达水平,CCK-8法、Transwell实验和流式细胞术分别检测circ0001429、miR-139-5p和TGIF1对T24细胞增殖、侵袭、迁移和凋亡的影响。结果:circ0001429在3珠膀胱癌细胞系中呈高表达(均P<0.01),敲降circ0001429可以显著抑制T24细胞增殖、侵袭、迁移并促进细胞凋亡(P<0.05或P<0.01);双荧光素酶报告基因验证结果显示,circ0001429与miR-139-5p、miR-139-5p与TGIF1存在靶向关系;过表达miR-139-5p显著抑制T24细胞增殖、侵袭、迁移并促进细胞凋亡(均P<0.01)。回复实验进一步证实circ0001429和TGIF1竞争性结合miR-139-5p促进T24细胞增殖、侵袭、迁移且抑制细胞凋亡(均P<0.01)。结论:circ0001429与TGIF1竞争结合miR-139-5p促进膀胱癌细胞T24的增殖、侵袭、迁移且抑制细胞凋亡。

多聚嘧啶区结合蛋白1通过调控基因的可变剪接促进胆管癌细胞的生长、迁移及侵袭能力

胆管癌是一种起病隐匿、侵袭性强、致死率高的原发性恶性肿瘤。多聚嘧啶区结合蛋白1(polypyrimidine tract-binding protein 1,PTBP1)已被报道,在多种类型肿瘤组织中异常高表达并参与癌症进展,但其在胆管癌中的作用仍未见报道。该研究旨在探讨PTBP1在胆管癌中的生物学功能,并初步解析其分子机制。本文利用公开的癌症基因组图谱(the cancer genome atlas,TCGA)数据,分析了胆管癌及癌旁组织中的PTBP1 mRNA表达水平。结果显示,PTBP1在胆管癌组织中的表达水平显著高于癌旁组织(P<0.05)。随后,在胆管癌细胞系RBE和HuH28中,通过CCK-8和细胞平板克隆实验,评价了PTBP1对胆管癌细胞生长能力的影响。结果显示,过表达PTBP1可显著促进胆管癌细胞的生长(P<0.01),而敲低PTBP1显著抑制胆管癌细胞的生长(P<0.001)。Transwell和Invasion实验结果显示,过表达PTBP1可显著促进胆管癌细胞的迁移和侵袭(P<0.001),而敲低PTBP1显著抑制胆管癌细胞的迁移和侵袭(P<0.001)。转录物组测序和通路富集分析结果显示,在胆管癌细胞中,敲低PTBP1后上调表达的基因显著富集于p53信号通路;而下调表达的基因显著富集于胆固醇代谢、Rho GTPase和TGF-β等信号通路。基于上述转录物组测序数据,本文还分析发现,敲低PTBP1可导致一系列基因发生异常的mRNA可变剪接事件,例如参与TGF-β调控的TGIF1及与p53活性相关的GNAS基因等。综上所述,PTBP1可能通过调控一系列基因的可变剪接而影响多个癌症相关的信号通路,从而促进胆管癌的进展。

Ghrelin alleviates 6-hydroxydopamine-induced neurotoxicity in SH-SY5Y cells

Ghrelin is a neuropeptide that has various physiological functions and has been demonstrated to be neuroprotective in a number of neurological disease models.However,the underlying mechanisms of ghrelin in Parkinson’s disease remain largely unexplored.The current study aimed to study the effects of ghrelin in a 6-hydroxydopamine(6-OHDA)-induced Parkinson’s disease model and evaluate the potential underlying mechanisms.In the present study,we treated an SH-SY5 Y cell model with 6-OHDA,and observed that pretreatment with different concentrations of ghrelin(1,10,and 100 nM)for 30 minutes relieved the neurotoxic effects of 6-OHDA,as revealed by Cell Counting Kit-8 and Annexin V/propidium iodide(PI)apoptosis assays.Reverse transcription quantitative polymerase chain reaction and western blot assay results demonstrated that 6-OHDA treatment upregulatedα-synuclein and lincRNA-p21 and downregulated TG-interacting factor 1(TGIF1),which was predicted as a potential transcription regulator of the gene encodingα-synuclein(SNCA).Ghrelin pretreatment was able to reverse the trends caused by 6-OHDA.The Annexin V/PI apoptosis assay results revealed that inhibiting eitherα-synuclein or lincRNA-p21 expression with small interfering RNA(siRNA)relieved 6-OHDA-induced cell apoptosis.Furthermore,inhibiting lincRNA-p21 also partially upregulated TGIF1.By retrieving information from a bioinformatics database and performing both double luciferase and RNA immunoprecipitation assays,we found that lincRNA-p21 and TGIF1 were able to form a double-stranded RNA-binding protein Staufen homolog 1(STAU1)binding site and further activate the STAU1-mediated mRNA decay pathway.In addition,TGIF1 was able to transcriptionally regulateα-synuclein expression by binding to the promoter of SNCA.The Annexin V/PI apoptosis assay results showed that either knockdown of TGIF1 or overexpression of lincRNA-p21 notably abolished the neuroprotective effects of ghrelin against 6-OHDA-induced neurotoxicity.Collectively,these findings suggest that ghrelin exerts neuroprotective effects against 6-OHDA-induced neurotoxicity via the lincRNA-p21/TGIF1/α-synuclein pathway.