Notch信号通路与神经干细胞的增殖分化

Notch信号通路是调节细胞增殖分化的一条古老的途径，传统观点认为它是通过“旁侧抑制”发挥作用的，近来许多研究表明，Notch系统也有激活和指导细胞分化的作用。神经干细胞是一种有自新能力的多能干细胞，是神经元和神经胶质细胞的共同前体细胞，对于它的研究是一个全新的领域。这一老一新的结合可使我们从一个不同以往的角度看待一些神经系统疾病，如Alzheimer′s病等疾病的发病机制和治疗方案。     

Notch信号通路与神经干细胞的增殖分化

Notch信号通路是调节细胞增殖分化的一条古老的途径,传统观点认为它是通过“旁侧抑制”发挥作用的,近来许多研究表明,Notch系统也有激活和指导细胞分化的作用。神经干细胞是一种有自新能力的多能干细胞,是神经元和神经胶质细胞的共同前体细胞,对于它的研究是一个全新的领域。这一老一新的结合可使我们从一个不同以往的角度看待一些神经系统疾病,如Alzheimer's病等疾病的发病机制和治疗方案。     

缺氧对滋养细胞Notch信号通路的影响

目的探讨缺氧条件下Notch信号通路在滋养细胞中的表达改变。方法利用实时荧光定量PCR(RT-qPCR)技术检测二氯化钴(CoCl2)化学缺氧条件下人早孕绒毛滋养细胞株(the human first-trimester extravillous tropho-blast cell line,TEV-1)中Notch1及Jagged1 mRNA的表达情况。结果 (1)与正常对照组相比,缺氧条件下滋养细胞Notch1 mRNA表达量无明显变化(P>0.05)。(2)随着缺氧时间的延长,滋养细胞Jagged1 mRNA表达量逐渐降低,与正常对照组相比具有统计学意义(P<0.05)。结论缺氧条件下滋养细胞Notch1及Jagged1表达平衡失调,可能参与滋养细胞功能调控。     

薯蓣皂苷通过调控SIRT1-FoxO1-自噬通路减轻糖尿病大鼠胰岛素抵抗

目的:探究薯蓣皂苷是否通过调控沉默信息调节因子1(sirtuin 1,SIRT1)-叉头框蛋白O1(forkhead box protein O1,FoxO1)-自噬通路减轻糖尿病大鼠胰岛素抵抗。方法:将60只SPF级SD大鼠随机分为对照组、模型组、低剂量(5 mg/kg)薯蓣皂苷组、中剂量(10 mg/kg)薯蓣皂苷组、高剂量(20 mg/kg)薯蓣皂苷组和薯蓣皂苷(20 mg/kg)+EX-527(SIRT1抑制剂)组,每组10只。高脂饲料喂养4周后腹腔注射链脲佐菌素以构建2型糖尿病(type 2 diabetes mellitus,T2DM)大鼠模型,低、中、高剂量薯蓣皂苷组和薯蓣皂苷+EX-527组大鼠分别灌胃相应剂量药物,对照组和模型组大鼠灌胃等量生理盐水,每天1次,为期4周。全自动生化分析仪检测血清中空腹血糖(fasting blood glucose,FBG)、高密度脂蛋白胆固醇(high-density lipoprotein cholesterol,HDL-C)、低密度脂蛋白胆固醇(low-density lipoprotein cholesterol,LDL-C)、甘油三酯(triglyceride,TG)和总胆固醇(total cholesterol,TC)水平,酶联免疫吸附实验检测血清空腹胰岛素(fasting insulin,FINS)水平,计算胰岛素抵抗指数(homeostasis model assessment-insulin resistance,HOMA-IR)和胰岛素敏感指数(insulin sensitivity index,ISI),行口服葡萄糖耐量实验(oral glucose tolerance test,OGTT),计算OGTT曲线下区域面积(area under curve,AUC);HE染色观察大鼠胰腺组织损伤情况;使用Western blot检测胰腺组织中beclin-1、LC3及SIRT1-FoxO1自噬通路相关蛋白的表达。结果:与对照组相比,模型组FBG、AUC、FINS、HOMA-IR、体重、TG、TC和LDL-C水平、胰腺组织损伤程度及FoxO1水平显著增加,ISI、beclin-1、LC3-II/LC3-I和SIRT1水平显著降低(P<0.05);与模型组相比,低、中、高剂量组FBG、AUC、FINS、HOMA-IR、体重、TG、TC和LDL-C水平、胰腺组织损伤程度及FoxO1水平以薯蓣皂苷剂量依赖性的方式显著降低,ISI、beclin-1、LC3-II/LC3-I和SIRT1水平以薯蓣皂苷剂量依赖性的方式显著增加(P<0.05);与高剂量薯蓣皂苷组相比,薯蓣皂苷+EX-527组FBG、AUC、FINS、HOMA-IR、体重、TG、TC和LDL-C水平、胰腺组织损伤程度及FoxO1水平显著增加,ISI、beclin-1、LC3-II/LC3-I和SIRT1水平显著降低(P<0.05)。结论:薯蓣皂苷可能通过激活SIRT1-FoxO1-自噬通路减轻T2DM大鼠胰岛素抵抗。     

薯蓣皂苷通过调控SIRT1-FoxO1-自噬通路减轻糖尿病大鼠胰岛素抵抗

目的:探究薯蓣皂苷是否通过调控沉默信息调节因子1(sirtuin 1,SIRT1)-叉头框蛋白O1(forkhead box protein O1,FoxO1)-自噬通路减轻糖尿病大鼠胰岛素抵抗。方法:将60只SPF级SD大鼠随机分为对照组、模型组、低剂量(5 mg/kg)薯蓣皂苷组、中剂量(10 mg/kg)薯蓣皂苷组、高剂量(20 mg/kg)薯蓣皂苷组和薯蓣皂苷(20 mg/kg)+EX-527(SIRT1抑制剂)组,每组10只。高脂饲料喂养4周后腹腔注射链脲佐菌素以构建2型糖尿病(type 2 diabetes mellitus,T2DM)大鼠模型,低、中、高剂量薯蓣皂苷组和薯蓣皂苷+EX-527组大鼠分别灌胃相应剂量药物,对照组和模型组大鼠灌胃等量生理盐水,每天1次,为期4周。全自动生化分析仪检测血清中空腹血糖(fasting blood glucose,FBG)、高密度脂蛋白胆固醇(high-density lipoprotein cholesterol,HDL-C)、低密度脂蛋白胆固醇(low-density lipoprotein cholesterol,LDL-C)、甘油三酯(triglyceride,TG)和总胆固醇(total cholesterol,TC)水平,酶联免疫吸附实验检测血清空腹胰岛素(fasting insulin,FINS)水平,计算胰岛素抵抗指数(homeostasis model assessment-insulin resistance,HOMA-IR)和胰岛素敏感指数(insulin sensitivity index,ISI),行口服葡萄糖耐量实验(oral glucose tolerance test,OGTT),计算OGTT曲线下区域面积(area under curve,AUC);HE染色观察大鼠胰腺组织损伤情况;使用Western blot检测胰腺组织中beclin-1、LC3及SIRT1-FoxO1自噬通路相关蛋白的表达。结果:与对照组相比,模型组FBG、AUC、FINS、HOMA-IR、体重、TG、TC和LDL-C水平、胰腺组织损伤程度及FoxO1水平显著增加,ISI、beclin-1、LC3-II/LC3-I和SIRT1水平显著降低(P<0.05);与模型组相比,低、中、高剂量组FBG、AUC、FINS、HOMA-IR、体重、TG、TC和LDL-C水平、胰腺组织损伤程度及FoxO1水平以薯蓣皂苷剂量依赖性的方式显著降低,ISI、beclin-1、LC3-II/LC3-I和SIRT1水平以薯蓣皂苷剂量依赖性的方式显著增加(P<0.05);与高剂量薯蓣皂苷组相比,薯蓣皂苷+EX-527组FBG、AUC、FINS、HOMA-IR、体重、TG、TC和LDL-C水平、胰腺组织损伤程度及FoxO1水平显著增加,ISI、beclin-1、LC3-II/LC3-I和SIRT1水平显著降低(P<0.05)。结论:薯蓣皂苷可能通过激活SIRT1-FoxO1-自噬通路减轻T2DM大鼠胰岛素抵抗。     

Notch1通过非经典的Notch信号通路调节胰腺星形细胞的活化

目的:探讨Notch1在胰腺星形细胞(pancreatic stellate cells,PSCs)活化中的作用。方法:利用免疫组织化学法与免疫荧光双标法检测Notch1在人胰腺导管腺癌(pancreatic ductal adenocarcinoma,PDAC)组织的表达情况;原代分离培养小鼠PSCs,利用油红O染色、Western blot及RT-qPCR法对其进行鉴定,并利用Western blot及RT-qPCR检测Notch1及其下游关键分子HES1的表达情况;转染Notch1小干扰RNA(Notch1 siRNA)至小鼠PSCs后,利用Western blot检测α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)、纤连蛋白(fibronectin)、I型胶原(collagen typeⅠ,ColⅠ)、Notch1及HES1的表达情况;利用划痕实验与CCK-8实验检测Notch1 siRNA对小鼠PSCs迁移与细胞活力的影响。结果:免疫组化与免疫荧光双标染色结果显示,Notch1表达在α-SMA阳性的PDAC间质细胞中;成功培养了小鼠PSCs细胞,且...     

miR-34a通过Notch1信号通路对肺癌干细胞的抑制

BACKGROUND:It has been proved that miR-34a plays an inhibitory role in the growth of lung cancer stem cells, but the underlying mechanism remains unclear. OBJECTIVE:To explore the inhibitory effect of miR-34a on lung cancer stem cells and the underlying mechanism. METHODS:The CD133⁺ lung cancer stem cells were separated from lung cancer A549 cell lines using magnetic activated cell sorting method. And miR-34a-overexpressing CD133⁺ lung cancer stem cells were established by liposome transfection technology. Besides, the targeted relationship between miR-34a and Notch1 was analyzed by the dual-luciferase reporter. Afterwards, Notch1 silencing was performed by gene knockout, and its effect on lung cancer stem cells was determined. RESULTS AND CONCLUSION:After sorted and detected by immunomagetic selection and flow cytometry assay respectively, a high rate of CD133⁺ lung cancer stem cell was obtained. And qRT-PCR detected that the expression level of miR-34a in CD133⁺ lung cancer stem cells was significantly lower than that in CD133^- lung cancer stem cells. Moreover, miR-34a-overexpressing CD133⁺ lung cancer stem cells were successfully constructed and miR-34a significantly inhibited proliferation and induced apoptosis of lung cancer stem cells. Dual-luciferase reporter assay indicated that Notch1 mRNA was a target of miR-34a. In addition, Notch1 silencing obviously inhibited proliferation and induced apoptosis of lung cancer stem cells. These findings suggest that miR-34a can inhibite lung cancer stem cells via the Notch1 signaling pathway.     

薯蓣皂苷抑制ERK/p38MAPK信号通路减轻过敏性哮喘小鼠炎症反应

目的探讨薯蓣皂苷对过敏性哮喘小鼠炎症反应的影响及对ERK/p38MAPK信号通路的调控作用。方法 SPF级BALB/c小鼠40只,随机分为对照组、过敏性哮喘模型组、薯蓣皂苷组与地塞米松组,每组10只。利用卵白蛋白致敏联合雾化激发法建立小鼠过敏性哮喘模型。HE染色观察肺组织炎症细胞浸润情况;ELISA检测小鼠血清中OVA特异性免疫球蛋白和小鼠肺泡灌洗液中炎性因子表达;Western blot检测各组小鼠肺组织MAPK信号通路相关蛋白ERK1/2、p38 MAPK、JNK、p-ERK1/2、p-p38 MAPK及p-JNK蛋白表达。结果薯蓣皂苷降低过敏性小鼠肺组织炎性浸润,降低血清中OVA特异性IgE含量(P0.05),降低BALF中炎性因子IL-4、IL-5及IL-13,促进IFN-的表达水平(P0.05),抑制哮喘小鼠肺组织p-ERK1/2,p-p38 MAPK及p-JNK蛋白的表达水平(P0.05)。结论薯蓣皂苷抑制过敏性哮喘小鼠炎症反应,与MAPK信号通路相关。     

Notch信号通路与肝癌的研究进展

Notch信号通路是一种高度保守的信号通路,在调节细胞分化、增殖和凋亡等一系列生理病理过程中都起着关键性的作用。Notch信号在肝癌中频繁发生异常表达及激活突变,其通过多种机制促进肝癌的发生发展,且与肝癌的侵袭、转移和预后密切相关。因此,Notch信号可作为肝癌治疗的一个靶标,为肝癌的治疗提供新的方向和机遇。     

SASH1 inhibits proliferation and invasion of thyroid cancer cells through PI3K/Akt signaling pathway

The SASH1 (SAM- and SH3-domain containing 1) gene, a member of the SLY-family of signal adapter proteins, has an important regulatory role in tumorigenesis, but its implication in thyroid carcinoma has not been yet investigated. In this study, we investigated the role of SASH1 in proliferation and invasion of thyroid cancer cells and the underlying mechanism. Our results demonstrated that SASH1 is down-regulated in thyroid cancer cells. Overexpression of SASH1 inhibits thyroid cancer cell proliferation, migration and invasion with decreased epithelial-mesenchymal transition (EMT). Mechanistically, overexpression of SASH1 inhibits thyroid cancer cell proliferation and invasion through down-regulation of PI3K and Akt phosphorylation. Taken together, the present study showed that the loss or inhibition of SASH1 expression may play an important role in thyroid cancer development, invasion, and metastasis and that SASH1 may be a potential therapeutic target for the treatment of thyroid cancer.     

叶酸通过下调ERK1/2信号通路抑制血管平滑肌细胞增殖和迁移

目的:探讨叶酸(folic acid,FA)对血管平滑肌细胞(VSMCs)增殖和迁移的影响及其机制。方法:取SD大鼠的主动脉,采用组织贴块法培养VSMCs,随机分组进行实验。采用CCK-8和Ed U法检测叶酸对VSMCs活力和增殖能力的影响。采用划痕实验和Transwell法检测叶酸对VSMCs迁移和侵袭的影响。采用Western blot法检测细胞增殖核抗原(PCNA)蛋白表达以及血小板源性生长因子受体(PDGFR)和细胞外信号调节激酶1/2(ERK1/2)蛋白的磷酸化水平。结果:叶酸抑制血小板源性生长因子(PDGF)诱导的VSMCs的活力,并呈浓度依赖性(P0.05)。叶酸抑制PDGF诱导的VSMCs的迁移,并呈浓度依赖性(P0.05)。叶酸降低PCNA表达和PDGFR磷酸化水平,并抑制PDGF激活的ERK1/2信号通路。结论:叶酸降低PDGF诱导的VSMCs PCNA和p-PDGFR蛋白水平,下调ERK1/2信号通路,从而抑制VSMCs的增殖和迁移。     

MiR-211 inhibits cell proliferation and invasion of gastric cancer by down-regulating SOX4

Introduction: Previous studies have shown that the dysregulation of miRNAs are frequently associated with cancer progression. Deregulation of miR-211 has been observed in various types of human cancers. However, its biological function in gastric cancer (GC) is still unknown. Methods: The expression of miR-211 in GC was detected by using quantitative real-time PCR (qRT-PCR). The miR-211 mimics and inhibitor were designed and transfected into BGC-823 cells. Then, we explore the probable biological function of miR-211 in gastric cancer cell proliferation and invasion in vitro. A luciferase reporter assay and western blot were performed to confirm the target gene of miR-211. Results: MiR-211 was significantly down-regulated in GC. Over-expression of miR-211 inhibited gastric cancer cell proliferation and invasion in vitro, conversely, down-regulated expression of miR-211 promoted gastric cancer cell proliferation and invasion. In addition, the sex-determining region Y-related high mobility group box 4 (SOX4) is identified as a target of miR-211 in GC cells, and SOX4 expression levels was inversely correlated with miR-211. Furthermore, knockdown of Sox4 inhibited the proliferation and invasion in GC cells. Conclusion: miR-211 could inhibit GC cell proliferation and invasion partially by down-regulating SOX4. MiR-211 might be a potential therapeutic target for GC treatment in the future.     

miR-145-5p靶向TPM3通过ERK信号通路抑制甲状腺癌TPC-1细胞侵袭和转移

目的 探讨miR-145-5p对甲状腺癌细胞侵袭和转移的影响.方法 将miR-145-5p mimic质粒、mimic-NC质粒、TPM3质粒分别或联合转入甲状腺癌细胞,RT-qPCR检测miR-145-5p与TPM3 mRNA的表达,双荧光素酶报告检测靶向关系,Transwell法检测细胞侵袭能力,划痕实验检测细胞迁...     

Reprogramming of cancer-associated fibroblasts by apoptotic cancer cells inhibits lung metastasis via Notch1-WISP-1 signaling

The interplay between apoptotic cancer cells and the tumor microenvironment modulates cancer progression and metastasis. Cancer-associated fibroblasts (CAFs) play a crucial role in promoting these events through paracrine communication. Here, we demonstrate that conditioned medium (CM) from lung CAFs exposed to apoptotic cancer cells suppresses TGF-β1-induced migration and invasion of cancer cells and CAFs. Direct exposure of CAFs to apoptotic 344SQ cells (ApoSQ) inhibited CAF migration and invasion and the expression of CAF activation markers. Enhanced secretion of Wnt‐induced signaling protein 1 (WISP-1) by CAFs exposed to ApoSQ was required for these antimigratory and anti-invasive effects. Pharmacological inhibition of Notch1 activation or siRNA-mediated Notch1 silencing prevented WISP-1 production by CAFs and reversed the antimigratory and anti-invasive effects. Enhanced expression of the Notch ligand delta-like protein 1 on the surface of ultraviolet-irradiated apoptotic lung cancer cells triggered Notch1-WISP-1 signaling. Phosphatidylserine receptor brain-specific angiogenesis inhibitor 1 (BAI1)-Rac1 signaling, which facilitated efferocytosis by CAFs, participated in crosstalk with Notch1 signaling for optimal production of WISP-1. In addition, a single injection of ApoSQ enhanced WISP-1 production, suppressed the expression of CAF activation markers in isolated Thy1⁺ CAFs, and inhibited lung metastasis in syngeneic immunocompetent mice via Notch1 signaling. Treatment with CM from CAFs exposed to ApoSQ suppressed tumor growth and lung metastasis, whereas treatment with WISP-1-immunodepleted CM from CAFs exposed to ApoSQ reversed the antitumorigenic and antimetastatic effects. Therefore, treatment with CM from CAFs exposed to apoptotic lung cancer cells could be therapeutically applied to suppress CAF activation, thereby preventing cancer progression and metastasis.     

METTL3 promotes the proliferation and invasion of esophageal cancer cells partly through AKT signaling pathway

Methyltransferase-like 3 (METTL3) is identified as a methyltransferase responsible for N⁶-methyladenosine (m⁶A) modification of mRNA, miRNA and lncRNA. Emerging evidences suggest that METTL3 is involved in tumorigenesis and progression of multiple tumor types. However, the functional role of METTL3 in esophageal cancer (EC) remains unclear. We used specific shRNA to down-regulate the METTL3 expression, and used pcDNA3.1-METTL3 cDNA plasmid to up-regulate the METTL3 expression in Eca-109 and KY-SE150 cells. Biological functions of METTL3 were performed by CCK-8, colony formation, apoptosis analysis, transwell and wound healing assays. Finally, an in-depth mechanism study was performed by an AKT inhibitor. METTL3 knockdown reduced the proliferation, clonality, migration and invasion of Eca-109 and KY-SE150 cells, and induced cell apoptosis, which may be mediated by activation of the mitochondrial apoptotic pathway. Further, METTL3 overexpression promoted the proliferation, clonality, migration and invasion of Eca-109 and KY-SE150 cells, and inhibited cell apoptosis. In addition, METTL3 regulated the expression of Wnt/β-catenin and AKT signaling pathway components. A double-effect inhibitor (BEZ235) inhibited AKT and mTOR phosphorylation and hindered the effect of METTL3 overexpression on the proliferation and migration of Eca-109 and KY-SE150 cells. Our data suggest that METTL3 plays a carcinogenic role in human EC progression partially through AKT signaling pathways, suggesting that METTL3 may serve as a potential therapeutic target for EC therapy.     

大黄素抑制肺癌A549细胞增殖、迁移和侵袭及对SDF1/CXCR4轴信号通路的影响

目的探讨大黄素对人肺癌A549细胞系增殖、侵袭和迁移能力以及SDF1/CXCR4轴信号通路的影响。方法采用MTT法检测不同浓度大黄素对肺癌A549细胞系的抑制率。通过划痕实验、Transwell小室侵袭实验分别检测大黄素对A549细胞迁移及侵袭能力的影响。荧光定量PCR检测细胞中SDF1和CXCR4基因表达,Western blot法检测A549细胞内SDF1/CXCR4轴信号通路中SDF1和CXCR4等关键蛋白表达水平的变化情况。结果大黄素对肺癌A549细胞的增殖具有抑制作用,呈浓度依赖性。大黄素以浓度依赖的方式抑制A549细胞的增殖、侵袭和迁移。荧光定量PCR检测发现大黄素处理A549细胞中SDF1和CXCR4基因表达降低。Western blot结果提示大黄素可抑制SDF1/CXCR4轴信号通路的SDF1和CXCR4蛋白的表达。结论在一定浓度范围内,大黄素可抑制人非小细胞肺癌A549细胞的增殖、迁移和侵袭,下调分泌蛋白SDF1和CXCR4的表达,其机制可能与抑制SDF1/CXCR4轴信号通路中的SDF1和CXCR4蛋白有关。     

Trichosanthin inhibits the proliferation of cervical cancer cells and downregulates STAT-5/C-myc signaling pathway

Background

Previous studies have indicated that Trichosanthin (TCS) exerts anti-virus, immunoregulation and a broad spectrum anti-tumor pharmacological activities. Trichosanthin is a promising agent for the treatment of cervical cancer. However, the exact effects and potential mechanism of TCS on cervical cancer are not well known.