干扰SULT2B1抑制人肝癌细胞BEL-7402的上皮间质化

目的研究羟基类固醇硫酸基转移酶SULT2B1与人肝癌细胞BEL-7402上皮间质转化的关系及其作用机制。方法细胞分为空白对照组(NC)、阴性对照组(control-siRNA)和SULT2B1干扰组(SULT2B1-siRNA),LipofectamineTM2000脂质体转染细胞,real-time PCR和Western blot检测干扰效果。Western blot检测紧密连接蛋白(ZO-1)、波形蛋白(vimentin)和转录因子ZEB1的表达。结果 SULT2B1干扰BEL-7402细胞后其mRNA与蛋白表达均显著降低(P0.05),ZO-1表达水平升高(P0.05),vimentin的表达及ZEB1的蛋白水平均降低(P0.05)。结论干扰SULT2B1通过下调ZEB1的表达抑制人肝癌细胞BEL-7402的上皮间质化。     

CNTN-1促进人食管癌EC9706细胞侵袭和迁移

目的探讨接触蛋白-1(CNTN-1)在食管癌转移中的作用。方法 q PCR和Western blot检测食管癌细胞系EC9706中CNTN-1的表达;RNA干扰和CNTN-1过表达质粒转染调整EC9706细胞CNTN-1的表达,并将细胞分为空白对照组、scrambled siRNA组、CNTN-1 siRNA组、pcDNA3.1-vector组和pcDNA3.1-CNTN-1组;Brd U和Transwell实验分别检测EC9706细胞增殖、侵袭和迁移能力;qPCR和Western blot检测基质金属蛋白酶MMP-2和MMP-9的表达。结果 CNTN-1在食管癌细胞EC9706中mRNA和蛋白水平较与正常食管上皮细胞显著上调(P0.05);转染CNTN-1siRNA后,EC9706细胞CNTN-1表达水平显著降低(P0.05),细胞增殖、侵袭和迁移能力显著下降(P0.05),同时细胞中侵袭转移相关蛋白MMP-2和MMP-9表达明显下降(P0.05);CNTN-1过表达质粒转染细胞后,EC9706细胞内CNTN-1表达水平上调(P0.05),细胞增殖、迁移和侵袭能力显著升高,同时MMP-2和MMP-9表达明显升高(P0.05)。结论 CNTN-1可能通过调节MMP-2和MMP-9表达促进食管癌细胞的侵袭转移。     

FEN1 siRNA对胃癌细胞生物学特性的影响及机制研究

目的 探讨瓣状核酸内切酶1(FEN1)小干扰RNA(FEN1 siRNA)对胃癌细胞生物学特性的影响及机制。方法 培养胃癌细胞SGC7901,转染FEN1 siRNA和阴性对照序列(siRNA control)分别命名为干扰组和NC组,同时以不做处理的胃癌细胞SGC7901作为对照组。采用实时荧光定量PCR和Western blot检测FEN1 siRNA的转染效果,细胞划痕实验检测胃癌细胞SGC7901迁移能力,Transwell小室检测胃癌细胞的侵袭能力,Western blot检测胃癌细胞中基质金属蛋白酶-2(MMP-2)、基质金属蛋白酶-9(MMP-9)、β-连环蛋白(β-catenin)的蛋白相对表达水平。结果 干扰组细胞中FEN1 mRNA和蛋白水平明显低于对照组及NC组,差异均有统计学意义(P值均＜0.01),而NC组细胞中FEN1 mRNA和蛋白水平与对照组比较,差异均无统计学意义(P值均＞0.05)。干扰组细胞迁移能力、侵袭能力及MMP-2、MMP-9、β-catenin蛋白相对表达水平均明显低于对照组及NC组,差异均有统计学意义(P值均＜0.01);而NC组细胞迁移能力、侵袭能力及MMP-2、MMP-9、β-catenin蛋白相对表达水平与对照组比较,差异均无统计学意义(P值均＞0.05)。结论 转染FEN1 siRNA能够抑制胃癌细胞中FEN1的表达,可抑制胃癌细胞的迁移能力、侵袭能力,其作用机制可能与抑制MMP-2、MMP-9、β-catenin蛋白的表达水平有关。     

ATP1A1基因沉默抑制人胶质瘤细胞U251侵袭

目的探讨沉默Na+/K+ATP酶A1亚基(ATP1A1)对人U251胶质瘤细胞系侵袭能力的影响及其机制。方法用shRNA-ATP1A1慢病毒感染人U251胶质瘤细胞,RT-q PCR及Western blot分别检测ATP1A1 mRNA和蛋白的表达;MTT法检测细胞体外的增殖;细胞划痕实验及Transwell小室检测细胞的迁移及侵袭能力;Western blot检测基质金属蛋白酶2/9(MMP-2/9)的表达。结果沉默ATP1A1细胞的ATP1A1 mRNA和蛋白表达均受到了明显抑制;细胞的增殖和迁移、侵袭能力也显著受抑(P0.05);MMP-2和MMP-9的表达也明显降低(P0.05)。结论靶向ATP1A1干扰能够明显抑制胶质瘤U251细胞的体外增殖、迁移及侵袭,其机制可能与MMP-2、MMP-9的下调相关,ATP1A1可能作为胶质瘤治疗的一个潜在靶点。     

miR-149-3p 靶向FOXM1 抑制人胃癌细胞SGC-7901 生长和迁移

目的:探究miR-149-3p靶向FOXM1抑制人胃癌细胞SGC-7901生长和迁移的机制。方法:体外培养人胃癌细胞SGC-7901,并分为:Ctrl组、miR-NC组、miR-149-3p mimic组、pLV-FOXM1组和pLV-FOXM1+miR-149-3p mimic组;使用RT-PCR分别检测正常组织、原位肿瘤组织和转移后肿瘤组织中miR-149-3p和FOXM1 mRNA的表达水平并分析miR-149-3p与FOXM1的线性关系;使用miR-NC、miR-149-3p mimic转染细胞后检测miR-149-3p和FOXM1 mRNA表达水平;双荧光素酶检测miR-149-3p与FOXM1的靶向关系;CCK-8检测细胞增殖情况,体外侵袭实验检测细胞侵袭情况,划痕实验检测细胞迁移情况;蛋白质印迹检测N-cadherin、E-cadherin、MMP-2、MMP-9、FOXM1、PCNA、p21的表达水平。结果:相比原位肿瘤组织和转移后肿瘤组织,正常组织中FOXM1 mRNA表达较低、miR-149-3p表达较高。荧光素酶报告实验表明miR-149-3p序列上有FOXM1的结合位点。相比空白对照组(Ctrl),miR-149-3p mimic组细胞增长受到显著抑制,FOXM1、P21、E-cadherin蛋白表达水平显著升高(P0.05);单位面积细胞侵袭数目、细胞迁移能力、PCNA、N-cadherin、MMP-9、MMP-2蛋白表达水平显著降低(P0.05)。相比Ctrl组,pLV-FOXM1组细胞生长受到促进,FOXM1、P21、E-cadherin蛋白表达水平显著降低(P0.05);单位面积细胞侵袭数目、细胞迁移能力、PCNA、N-cadherin、MMP-9、MMP-2蛋白表达水平显著升高(P0.05)。相比pLV-FOXM1组,miR-149-3p+pLV-FOXM1组细胞增长受到显著抑制,FOXM1、P21、E-cadherin蛋白表达水平显著升高(P0.05);单位面积细胞侵袭数目、细胞迁移能力、PCNA、N-cadherin、MMP-9、MMP-2蛋白表达水平显著降低(P0.05)。结论:miR-149-3p可以靶向FOXM1抑制人胃癌细胞SGC-7901的生长侵袭和迁移,其机制与调控细胞生长侵袭和迁移的蛋白有关。     

LASS2/TMSG-1基因过表达对人肺癌95D细胞体外侵袭迁移能力的影响及其机制

目的分析LASS2/TMSG-1基因过表达对人肺癌95D细胞体外侵袭迁移能力的影响,初步探讨LASS2/TMSG-1基因的作用机制。方法运用脂质体转染法将前期已构建好并冷冻保存的Pc DNA3-TMSG-1质粒通过脂质体转染法瞬时转染入95D细胞(高转移潜能,LASS2/TMSG-1低表达),使外源性LASS2/TMSG-1基因在细胞内过表达即LASS2/TMSG-1过表达组,同时设立转染空白质粒的空白对照组和未转染质粒的阴性对照组。应用体外侵袭及迁移实验检测人肺癌95D细胞侵袭及迁移能力的变化;应用qRT-PCR和Western blot法检测LASS2/TMSG-1 mRNA及蛋白的表达;应用Western blot法检测ATP6L、MMP-2及MMP-9在细胞中的表达水平;应用明胶酶谱法检测肿瘤细胞中MMP-2及MMP-9的活性;使用比色法检测细胞中V-ATPase的活性;使用BCECF H+敏感探针检测细胞外H+浓度的变化。结果 LASS2/TMSG-1过表达组细胞的LASS2/TMSG-1表达水平明显升高,而ATP6L表达水平下降,其V-ATPase活性及细胞外H+浓度降低,与空白对照组和阴性对照组相比差异均具有统计学意义(P0.05);MMP-2、MMP-9的表达及活性均降低,与其他两组相比差异有统计学意义(P0.05);并且LASS2/TMSG-1过表达组细胞的体外侵袭及迁移能力明显低于其他两组(P0.05)。结论 LASS2/TMSG-1可能通过结合ATP6L亚基抑制V-ATPase活性,改变细胞外H+浓度,影响MMP-2、MMP-9的表达及活性,进而改变肿瘤细胞的体外侵袭迁移能力等生物学行为。     

基因沉默PRDX1 表达对人结直肠癌SW480 细胞侵袭迁移的影响

目的:探讨RNA 干扰过氧化还原酶1(Peroxiredoxin 1,PRDX1)表达对人结直肠癌SW480 细胞侵袭转移能力的影响。方法:筛选RNA 干扰PRDX1 的慢病毒质粒,与阴性对照慢病毒质粒分组转染结直肠癌SW480 细胞,转染后的SW480 细胞可分为PRDX1 基因沉默组(si-PRDX1)和阴性对照组(Vector)。实时荧光定量PCR(qRT-PCR)和免疫印迹法(Western blot)分别检测两组细胞中PRDX1 mRNA 和蛋白表达;采用Transwell 侵袭和迁移实验检测基因沉默PRDX1 表达对结直肠癌细胞侵袭及迁移能力的影响;通过Western blot 检测两组细胞中基质金属蛋白酶(MMP)家族部分蛋白表达水平。结果:基因沉默PRDX1 表达可有效抑制结直肠癌SW480 细胞中PRDX1 mRNA 和蛋白水平的表达,与阴性对照组相比(Vector),差异均具有统计学意义(P<0.01),说明基因沉默PRDX1 的SW480 细胞系构建成功;Transwell 侵袭和迁移实验显示si-PRDX1组细胞的侵袭及迁移能力较对照组均明显降低(P<0.01);Western blot 结果显示,与Vector 组相比,si-PRDX1 组细胞中组织基质金属蛋白酶抑制剂2(TIMP-2)的表达明显增加,而MMP-2 及MMP-9 的表达显著下降,且差异均具有统计学意义(P<0.05)。结论:基因沉默人结直肠癌SW480 细胞的PRDX1 表达可有效抑制细胞的侵袭、迁移及转移能力,其机制可能会通过调控TIMP-2、MMP-2 及MMP-9 的表达介导。     

全反式维甲酸对小鼠肝癌细胞Hepa1-6增殖、迁移、侵袭的影响及其机制

目的探讨不同浓度的全反式维甲酸(ATRA)对小鼠肝癌细胞Hepa1-6体外增殖、凋亡、迁移和侵袭的影响及肝癌细胞间质标志蛋白和miR200家族的表达情况。方法以Hepa1-6小鼠肝癌细胞为研究对象,给予0、0.1、1.0和10.0μmol/L终浓度的ATRA处理,结晶紫染色检测细胞增殖,锥虫蓝拒染实验计数活细胞。Hoechst检测细胞凋亡,划痕实验检测迁徙能力,Transwell实验检测侵袭能力,荧光定量PCR(real-time PCR)法检测间质标志蛋白N-cadherin、sail和vimentin和0和10μmol/L ATRA处理后的miR200家族的mRNA表达。结果 ATRA处理后Hepa1-6细胞的增殖、迁移、侵袭能力明显下降(P0.05),凋亡率增高(P0.05),间质标志蛋白N-cadherin、sail和vimentin的表达明显下调(P0.05),ATRA的浓度越高,这些作用越明显。10μmol/L ATRA处理后miRNA200a-3p,200c-3p,141-3p显著上调。结论 ATRA呈浓度依赖性促进肿瘤细胞Hepa1-6凋亡,抑制其增殖、迁移及侵袭能力,这可能与ATRA上调microRNA200家族,抑制细胞的间质表型有关。     

Effects of hypoxia on migration and invasion of esophageal carcinoma Eca109 cells

目的 探讨低氧对食管癌迁移及侵袭能力的影响及其作用机制.方法 采用CoCl2化学低氧法模拟肿瘤低氧微环境,半定量RT-PCR和免疫细胞化学分别检测不同低氧时相时食管癌Eca109细胞中低氧诱导因子-1α(HIF-1α)、E-钙黏蛋白及基质金属蛋白酶-2(MMP-2)mRNA及蛋白的表达.Western印迹法检测雷帕霉素联合低氧处理Eca109细胞后,HIF-1α、E-钙黏蛋白及MMP-2的变化.细胞划痕试验和Transwell实验检测雷帕霉素联合低氧对Eca109细胞迁移及侵袭能力的影响.结果 Eca109细胞在低氧状态下,HIF-1α mRNA无明显变化,仅蛋白表达增多;E-钙黏蛋白的mRNA表达明显降低(P＜0.05),蛋白表达减少;MMP-2 mRNA表达明显升高(P＜0.05),蛋白表达增多.雷帕霉素在低氧状态下可显著抑制HIF-1α及MMP-2表达,促进E-钙黏蛋白高表达.经雷帕霉素处理后,Eca109细胞在低氧状态下,迁移速度减慢,侵袭穿膜细胞数减少(P＜0.05).结论 低氧使Eca109细胞中HIF-1α蛋白表达增多,后者可能通过下调E-钙黏蛋白、上调MMP-2表达促进食管癌在低氧状态下的迁移及侵袭.     

siRNA沉默染色质解旋酶DNA结合蛋白1对卵巢癌HO-8910PM细胞增殖、侵袭、迁移的影响

目的:探究siRNA沉默染色质解旋酶DNA结合蛋白1(CHD1L)对卵巢癌HO-8910PM细胞增殖、侵袭、迁移及相关分子如核因子κB(NF-κB)、基质金属蛋白酶(MMP)的影响。方法:将si-CHD1L、si-NC质粒转染至卵巢癌HO-8910PM细胞,命名为si-CHD1L组、si-NC组,以未经转染细胞作为对照组,实时荧光定量PCR(qRT-PCR)检测细胞CHD1L mRNA表达; CCK-8法检测细胞增殖抑制情况;划痕实验检测细胞迁移能力;Transwell小室系统检测细胞迁移、侵袭能力;蛋白免疫印迹(WB)检测NF-κB、MMP-2、MMP-9蛋白表达。结果:与对照组、si-NC组比较,si-CHD1L组细胞CHD1L mRNA表达降低(P0.05),细胞增殖抑制率升高,细胞迁移能力降低,迁移、侵袭数量降低(P0.05)。与对照组、si-NC组相比,si-CHD1L组NF-κB、MMP-2、MMP-9蛋白表达降低(P0.05)。结论:siRNA沉默CHD1L能够抑制卵巢癌HO-8910PM细胞增殖、侵袭、迁移,并能抑制NF-κB、MMP蛋白的表达,为卵巢癌的靶向治疗提供一定的理论依据。     

SARS-CoV-2 virus NSP14 Impairs NRF2/HMOX1 activation by targeting Sirtuin 1

Most deaths from the COVID-19 pandemic are due to acute respiratory distress syndrome (ARDS)-related respiratory failure. Cytokine storms and oxidative stress are the major players in ARDS development during respiratory virus infections. However, it is still unknown how oxidative stress is regulated by viral and host factors in response to SARS-CoV-2 infection. Here, we found that activation of NRF2/HMOX1 significantly suppressed SARS-CoV-2 replication in multiple cell types by producing the metabolite biliverdin, whereas SARS-CoV-2 impaired the NRF2/HMOX1 axis through the action of the nonstructural viral protein NSP14. Mechanistically, NSP14 interacts with the catalytic domain of the NAD-dependent deacetylase Sirtuin 1 (SIRT1) and inhibits its ability to activate the NRF2/HMOX1 pathway. Furthermore, both genetic and pharmaceutical evidence corroborated the novel antiviral activity of SIRT1 against SARS-CoV-2. Therefore, our findings reveal a novel mechanism by which SARS-CoV-2 dysregulates the host antioxidant defense system and emphasize the vital role played by the SIRT1/NRF2 axis in host defense against SARS-CoV-2.     

Nucleosome-binding activities within JARID2 and EZH1 regulate the function of PRC2 on chromatin

Polycomb-repressive complex 2 (PRC2) comprises specific members of the Polycomb group of epigenetic modulators. PRC2 catalyzes methylation of histone H3 at Lys 27 (H3K27me3) through its Enhancer of zeste (Ezh) constituent, of which there are two mammalian homologs: Ezh1 and Ezh2. Several ancillary factors, including Jarid2, modulate PRC2 function, with Jarid2 facilitating its recruitment to target genes. Jarid2, like Ezh2, is present in poorly differentiated and actively dividing cells, while Ezh1 associates with PRC2 in all cells, including resting cells. We found that Jarid2 exhibits nucleosome-binding activity that contributes to PRC2 stimulation. Moreover, such nucleosome-binding activity is exhibited by PRC2 comprising Ezh1 (PRC2–Ezh1), in contrast to PRC2–Ezh2. The presence of Ezh1 helps to maintain PRC2 occupancy on its target genes in myoblasts where Jarid2 is not expressed. Our findings allow us to propose a model in which PRC2–Ezh2 is important for the de novo establishment of H3K27me3 in dividing cells, whereas PRC2–Ezh1 is required for its maintenance in resting cells.     

人Man2c1转基因小鼠模型的建立

目的 为在体内研究MAN2C1的生物学意义而建立转hMan2c1基因的小鼠。方法 构建pIRKS2-EGFP-hMan2c1重组表达载体，经体外转染实验鉴定转染的基因能在COS-7细胞表达后，注射人ICR小鼠受精卵，以制备转基因小鼠。用基因组PCR鉴定目的基因在宿主基因组DNA的整合。用RT-PCR和Westernblot分析hMan2c1在转基因小鼠的表达。结果 在116只原代小鼠中，有7只hMan2c1基因组PCR阳性。在所检测的20只F1代小鼠中，有9只hMan2c1基因组PCR阳性。在所检测的21只F2代小鼠中，有16只基因组PCR阳性。用鼠尾组织RT-PCR和Western blot检测hMan2c1基因表达，确定基因组PCR阳性的7个系中有4个系阳性。结论 建立了4个稳定表达hMan2c1的转基因小鼠系，为深入研究MAN2C1的生物学意义打下了基础。     

Role of LFA-1/ICAM-1 in interleukin-2-stimulated lymphocyte proliferation

Major adhesion routes between lymphoid cells involve the receptor/ligand pairs LFA-l/ICAM-1 and CD2/LFA-3, in addition to VLA or CD44 molecules. In this study we evaluated the role of these adhesion receptors in the proliferative response of lymphoid cells to interleukin-2 (IL-2). Blocking studies were performed with a panel of monoclonal antibodies (mAb) directed against these adhesion molecules. Selective inhibition of recombinant (r)IL-2-induced cell proliferation was observed with mAb directed against the a or /3 subunit of LFA-1 or to its ligand ICAM-1. Interestingly, rIL-2-induced proliferation was also inhibited by NKI-L16, an anti-la antibody known to enhance cell-cell interaction. Resting lymphocytes were preferentially susceptible to the inhibition, particularly in an early phase of culture and when stimulated with a relatively low dose of rIL-2. By using mAb that specifically could block distinct rIL-2 activation pathways, LFA-l/ICAM-1 interaction was found to be required for p55 IL-2 receptor (IL-2R)-mediated interaction of rIL-2 with its high-affinity receptor, but not for p75 IL-2R-mediated responses. Furthermore, it was shown that the rIL-2 response of T lymphocytes, but not of natural killer cells, was dependent on LFA-l/ICAM-1 interaction. This suggests that LFA-l/ICAM-1 interaction is required for an optimal rIL-2 response of cells capable of IL-2 secretion. Our data provide evidence for the hypothesis that adhesion receptor-directed release of IL-2 may result in a locally high concentration of IL-2 that triggers high-affinity IL-2R signaling and up-regulates p55 IL-2R to enhance cytokine responsiveness.     

Lack of F1 anti-parental resistance in H-2b/d F1 hybrids devoid of β2-microglobulin

F₁ hybrid mice often reject parental hematopoietic grafts, a phenomenon known as hybrid resistance. Hybrid resistance is mediated by natural killer (NK) cells and although the molecular interactions responsible for this phenomenon are largely unknown, one hypothesis suggests that parental cells are rejected because they fail to express a complete set of host major histocompatibility complex (MHC) class I molecules. Inherent in this theory is that NK cells in the F₁ hybrid are instructed by self MHC class I molecules to form an NK cell repertoire capable of reacting against cells lacking these self MHC class I molecules. Here, we show that C57BL/6 x DBA/2 mice (H-2^b/d) devoid of β₂-microglobulin (β₂m) are incapable of rejecting β₂m?/? parental C57BL/6 cells (H-2^b) both in vivo and in vitro. From this, we conclude that the development of an NK cell repertoire, at least in F₁ mice of the H-2^b/d haplotype, requires expression of MHC class I molecules complexed with β₂m.     

Th1/Th2、Tc1/Tc2亚群在乙肝肝硬化患者中的作用

目的 :探讨乙肝肝硬化患者外周血 (PBMC)中CD4 和CD8 T细胞内Th1和Th2类细胞的平衡状态 ,探明Th1、Th2类细胞在乙肝肝硬化中的作用。方法 :乙肝肝硬化患者CD4 T细胞和CD8 T细胞中IFN γ 和IL 4 细胞的百分率 ,观察乙肝肝硬化患者Th1 Th2、Tc1 Tc2比例的变化。结果 :乙肝肝硬化患者PBMC中CD4 ,CD8细胞 ,CD4 CD8比值与健康对照者相比无统计学差异 (P >0 0 5 ) ,Th1细胞及Tc1细胞百分率为 8 8% ,9 0 % ,较健康对照者 7 5 % ,7 7%升高 (P <0 0 5 )。结论 :乙肝肝硬化患者外周血T细胞亚群发生Th1类偏移 ,在乙肝肝硬化的发生和发展中可能起重要作用     

MMP2 role in breast cancer brain metastasis development and its regulation by TIMP2 and ERK1/2

Matrix metalloproteinase 2 (MMP2) is important in breast cancer (BC) invasion and metastasis. We previously reported that BC brain metastases, in a rat syngeneic model developed in our laboratory, have high expression and activity of MMP2. The MMP2 mechanism of action in the brain is still under intense scrutiny. To study the role of MMP2 in the development of BC brain metastasis we transfected ENU1564 rat mammary adenocarcinoma cells with tissue inhibitor of MMP2 (TIMP2). Animals inoculated with ENU1564-TIMP2 cells had decreased orthotopic tumor growth, decreased orthotopic metastastic behavior and did not develop brain metastases. These results were associated with decreased MMP2 activity, demonstrated by gel zymography. Mitogen activated protein kinase (MAPK) pathway components, such as ERK1/2, have been correlated to MMP expression and/or astrocyte activity. We found that BC brain metastases have peripheral astrocyte reactivity and higher expression of glial fibrillary acidic protein (GFAP) and phosphorylated-ERK1/2 (p-ERK1/2). Additionally, rat astrocyte-conditioned media increased in vitro invasion of ENU1564 cancer cells and increased expression of MMP2 and p-ERK1/2. Blockage of ERK1/2 phosphorylation by treatment with MEK inhibitor (PD98059) decreased the expression of MMP2 in cancer cells grown in rat astrocyte-conditioned media. Our results are highly suggestive that MMP2 plays a role in the development of BC metastases, in particular to the brain. Furthermore, our results suggest that astrocyte factors and the ERK1/2 signaling pathway may be associated with BC brain metastasis development; and that ERK1/2 may regulate MMP2 in a way that is modifiable by astrocyte factors.