趋化因子CXCL5通过调控ERK/MAPK信号通路抑制肿瘤免疫促进鼻咽癌恶化的机制研究

目的:探讨CXC趋化因子配体-5(CXCL5)促进鼻咽癌(NPC)恶化的作用,并研究其潜在的分子机制。方法:收集2017年6月~2019年2月我院收治的98例NPC患者作为研究对象。另选取38例同期在我院进行体检的健康志愿者作为对照。ELISA检测NPC患者和健康者的血清CXCL5水平。免疫组化和Western blot检测NPC患者肿瘤组织及癌旁正常组织中CXCL5及其受体CXCR2的表达水平。Western blot检测CXCL5对CNE-2细胞PI3K/AKT、ERK/MAPK及NF-κB信号通路的影响。用稳定表达CXCL5或对照质粒的CNE-2细胞建立小鼠鼻咽癌移植瘤模型,绘制肿瘤生长及小鼠生存曲线。Western blot检测各组小鼠肿瘤组织中CXCL5及p-ERK1/2的表达水平。流式细胞术检测各组小鼠肿瘤组织中CD4+T细胞、CD8+T细胞与CD56+CD16+NK细胞数量。分离BALB/c小鼠的外周血单核细胞(PBMC),使用重组CXCL5蛋白与ERK/MAPK信号通路抑制剂SCH772984处理后检测NK细胞的活性水平。结果:NPC患者的血清CXCL5水平显著高于健康者(P<0.05)。NPC患者肿瘤组织中CXCL5与CXCR2的表达水平均显著高于癌旁正常组织(P<0.05)。CXCL5能显著增加CNE-2细胞p-ERK1/2的表达水平(P<0.05)。与对照组相比,过表达CXCL5组小鼠的肿瘤生长曲线与生存曲线有显著差异(P<0.05)。过表达CXCL5组小鼠肿瘤组织CXCL5与p-ERK1/2的表达水平均显著高于对照组(P<0.05)。过表达CXCL5组小鼠肿瘤组织中CD4+T细胞、CD8+T细胞与CD56+CD16+NK细胞数量均显著低于对照组小鼠(P<0.05)。重组CXCL5处理能显著降低正常PBMC中NK细胞的活性(P<0.05),而不影响SCH772984预处理的PBMC中NK细胞的活性(P>0.05)。结论:NPC患者血清及肿瘤组织中CXCL5的水平均显著增高,CXCL5可能通过调控ERK/MAPK信号通路抑制肿瘤免疫从而发挥促进NPC恶化的作用。

lncRNA GAS5通过抑制MAPK/ERK信号通路阻断乳腺癌细胞的上皮-间质转化过程

目的:探讨lncRNA GAS5对乳腺癌细胞恶性生物学行为的影响及相关机制。方法:采用qPCR检测lncRNA GAS5在乳腺癌组织中和细胞系中的表达差异;Transwell实验和划痕实验分别检测lncRNA GAS5对乳腺癌细胞侵袭和迁移的影响;Western blot检测lncRNA GAS5对EMT的影响以及潜在作用机制;裸鼠成瘤实验验证lncRNA GAS5对动物体内成瘤的影响。结果:与癌旁正常组织相比,lncRNA GAS5在乳腺癌组织中呈低表达,而且在MDA-MB-231细胞中的表达最低;lncRNA GAS5的上调显著减低了MDA-MB-231细胞的侵袭和迁移能力;lncRNA GAS5的过表达使MDA-MB-231细胞中的E-cadherin蛋白显著升高,而N-cadherin、Vimentin和Snail蛋白的表达显著降低,而使用MAPK/ERK信号通路的抑制剂U0126能抵消lncRNA GAS5对MDA-MB-231细胞EMT的影响;结论:lncRNA GAS5能通过抑制MAPK/ERK信号通路阻断乳腺癌细胞的上皮-间质转化过程。

miR-508-5p慢病毒过表达载体构建及对MAPK1/ERK信号通路靶向抑制作用的研究

目的:构建能高效表达成熟miR-508-5p小分子的慢病毒过表达载体,研究其对MAPK1/ERK信号通路靶向调控作用。方法:利用化学合成miR-508-5p茎环结构RNA,并将其克隆入线性化的pSicoR质粒中,经双酶切及测序鉴定;同时构建与miR-508-5p互补靶基因MAPK1的3'非翻译区,将其克隆入线性化的Report载体中。利用脂质体转染试剂将鉴定阳性的pSicoR-miR-508-5p重组质粒转染HEK-293T细胞,进一步通过Relative luciferase activity、Western blot及real-time PCR试验检测MAPK1蛋白和mRNA相对表达水平。结果:酶切及测序结果证明成功构建pSicoR-miR-508-5p及Report-MAPK1 3'-UTR重组质粒,并通过实验证实miR-508-5p过表达明显抑制MAPK1的蛋白表达水平及mRNA相对含量(P<0.05);抑制miR-508-5p的表达,又明显上调MAPK1的蛋白表达水平及mRNA相对含量(P<0.05)。结论:成功构建pSicoR-miR-508-5p慢病毒过表达载体,证实miR-508-5p直接靶标MAPK1的表达,在转录后水平对其进行负调控,为进一步研究miRNA对细胞通路和细胞周期的调控作用奠定了基础。

Phytochemical analysis of Berberis lyceum methanolic extract and its antiviral activity through the restoration of MAPK signaling pathway modulated by HCV NS5A

Objective:To evaluate the antiviral activity and phytochemicals of selected plant extracts and their effect on the mitogen-activated protein kinase(MAPK)signaling pathway modulated by hepatitis C virus(HCV)nonstructural protein 5 A(NS5A).Methods:A total of ten plant extracts were initially screened for their toxicities against Hep G2 cells.The non-toxic plants were tested for their inhibitory effect on the expression of HCV NS5A at both m RNA and protein levels using real-time PCR and Western blotting assays,respectively.The differential expression of the genes associated with MAPK pathway in the presence of NS5A gene and plant extract was measured through real-time PCR.Subsequently,the identification of secondary metabolites was carried out by phytochemical and HPLC analysis.Results:The phytochemical profiling of Berberis lyceum revealed the presence of alkaloids,phenols,saponins,tannins,flavonoids,carbohydrates,terpenoids,steroids,and glycosides.Similarly,quercetin,myricetin,gallic acid,caffeic acid,and ferulic acid were identified through HPLC analysis.The methanolic extract of Berberis lyceum strongly inhibited HCV RNA replication with an IC50 of 11.44μg/m L.RT-PCR and Western blotting assays showed that the extract reduced the expression of HCV NS5A in a dosedependent manner.Berberis lyceum extract also attenuated NS5A-induced dysregulation of the MAPK signaling pathway.Conclusions:Our findings suggest that Berberis lyceum extract strongly inhibits HCV propagation by reducing HCV NS5A-induced perturbation of MAPK signaling.

Experimental study on the effect of cryoablation on lung cancer mice based on MAPK/ERK signaling pathway

Objective:To study the regulatory effect of cryoablation on MAPK/ERK signaling pathway in mice with lung adenocarcinoma.Methods:Lewis mouse lung adenocarcinoma cell line was used to establish subcutaneous transplanted tumor model in C57BL/6 mice.Ten mice were randomly divided into two groups:sham operation group and cryoablation group,with 5 mice in each group.The cryoablation group was treated with double circulation-rewarming ablation,and the sham operation group was treated with incision and suture at the transplanted tumor.The tumor tissues were taken 14 days after operation.Detect the effect of cryoablation on MAPK/ERK pathway related proteins by Western blot,such as KRAS,RAF1,MEK1,ERK1/2,P-RAF1,P-MEK1,P-ERK1/2.The expression of KRAS gene was further verified by qRt-PCR.Results:Compared with the sham operation group,the phosphorylated proteins P-RAF1,P-MEK1 and P-ERK1/2 in tumor tissue after cryoablation were decreased(P<0.05),and the key molecule KRAS in MAPK/ERK pathway was decreased in protein and gene expression(P<0.05).Conclusion:Cryoablation can negatively regulate MAPK/ERK signaling pathway by down-regulating KRas expression.

miR-431-5p通过MAPK/ERK通路促进食管鳞癌细胞增殖和迁移

为了检测miR-431-5p在食管鳞癌(Esophageal squamous cell carcinoma,ESCC)中的表达,探讨其功能,利用TCGA公共数据库分析miR-431-5p在食管癌中的表达,通过RT-qPCR检测miR-431-5p在组织和细胞中表达;再利用miR-431-5p模拟物和抑制剂,通过CCK-8实验、细胞划痕和Transwell实验以及蛋白免疫印迹实验,检测miR-431-5p对ESCC细胞增殖、侵袭和迁移的影响以及分子作用机制。结果显示:miR-431-5p在食管癌中高表达;转染miR-431-5p模拟物后,KYSE30细胞增殖率、迁移率和侵袭率分别增加了24.19%,30.86%和50.29%(P<0.05);而转染miR-431-5p抑制剂后,TE-11细胞数量、迁移率分别降低了21.43%和9.52%(P<0.05);miR-431-5p模拟物增加KYSE30细胞p-ERK表达量11.68%;miR-431-5p抑制剂降低TE-11细胞p-ERK表达量45.73%。研究结果表明:miR-431-5p通过MAPK/ERK通路促进ESCC细胞的增殖、侵袭和迁移。该研究为开发食管鳞癌治疗的有效靶点提供实验依据。

MAPK/ERK regulation of P53 in human epidermoid carcinoma cell line A431

Objective:To observe the impact of activation and inhibition of mitogen activated protein kinases(MAPK)/extracellular signalregulated protein kinase(ERK)signaling pathway on the proliferation and apoptosis of cutaneous squamous cell carcinoma(SCC).cells and investigate the interaction mechanism between MAPK/ERK signaling pathway and tumor suppressor gene P53 in SCC.Methods:Human A431 cells were cultured and divided into MAPK/ERK inhibition groups with low-,medium-and highconcentration of inhibitors(PD98059+DMSO),MAPK/ERK activation groups with low-,medium-and high-concentration of stimuli(IGF+PBS)and blank control group(DMSO).The cell proliferation in vitro was detected by MTT assay,with the cell apoptosis detected by flow cytometry(FCM)and the protein expression of P-ERK and P53 detected by western blot in each group.Results:The A431 cell proliferation was inhibited by different concentrations of PD98059 with a clear concentration-effect and time-effect relationship(p<.05);and the cell proliferation was promoted by the different concentrations of IGF with a clear concentration-effect and time-effect relationship(p<.05).The FCM results showed a significant increase in the apoptosis rate of A431 cells which were treated with PD98059,with a clear concentration-effect relationship(p<.05);while the apoptosis rate was decreased significantly after A431 cells were treated with IGF,also with a concentration-effect relationship(p<.05).The western blot results showed that the expression of P-ERK protein was decreased but the expression of P53 was increased after A431 cells were treated with PD98059.With the concentration of PD98059 going up,the decrease in P-ERK and the increase in P53 were more significant(p<.05);while the expression of P-ERK protein was increased but the expression of P53 was decreased after A431 cells were treated with IGF.With the concentration of IGF going up,the increase in P-ERK and the decrease in P53 were more significant(p<.05).According to Pearson correlation analysis,the expression of P53 was negatively correlated to that of P-ERK(p<.05).Conclusions:After MAPK/ERK signaling pathway was activated by IGF in A431 cells,the expression of pro-apoptotic factor P53 was decreased with the ability of cell proliferation enhanced and the ability of apoptosis reduced.However,after the inhibition of MAPK/ERK signaling pathway,the expression of pro-apoptotic factor P53 was increased with the ability of cell proliferation reduced and the ability of apoptosis increased.

参苓白术散通过ERK/p38 MAPK信号通路干预溃疡性结肠炎大鼠结肠组织AQP3、AQP4的表达

目的探讨细胞外信号调节激酶/p38丝裂原活化蛋白激酶(ERK/p38MAPK)信号通路在参苓白术散调控脾虚湿困型溃疡性结肠炎大鼠结肠组织水通道蛋白(aquaporin,AQP)3、AQP4表达中的作用。方法将60只Wistar大鼠按照随机数字表均分为正常组、模型组(氯化钠注射液)、参苓白术散组、U0126+参苓白术散组、SB203580+参苓白术散组。除正常组外,脾虚湿困型溃疡性结肠炎大鼠采用2,4,6-三硝基苯磺酸/乙醇灌肠,结合环境与饮食干预复制。14 d后采用蛋白质印迹法检测各组大鼠结肠组织AQP3、AQP4蛋白的表达,实时荧光定量PCR法检测其mRNA表达情况。结果模型组大鼠AQP3、AQP4蛋白表达及其mRNA的表达水平明显低于正常组(P<0.05),参苓白术散组大鼠结肠组织AQP3、AQP4蛋白及mRNA表达较模型组明显升高,组间比较有显著性差异(P<0.05),SB203580+参苓白术散组及U0126+参苓白术散组大鼠结肠组织AQP3、AQP4蛋白及mRNA表达较模型组有较小幅度升高,与正常组和参苓白术散组相比均有显著性差异(P<0.05)。结论参苓白术散可显著改善大鼠结肠组织AQP3、AQP4蛋白及mRNA表达,ERK/p38 MAPK信号通路参与了参苓白术散对脾虚湿困型溃疡性结肠炎大鼠结肠组织AQP3、AQP4表达的调节作用。

ERK5信号通路与恶性肿瘤研究进展

丝裂原活化蛋白激酶家族是一类介导细胞反应的重要信号系统,是细胞外信号调节激酶5(ERk5)是丝裂原活化蛋白激酶(MAPK)信号通路的重要组成部分,作为MAPK家族发现较晚的转导体,可以被许多胞外刺激因素激活,参与细胞的增殖、分化、凋亡等,诱导细胞发生相应生物学变化,参与机体多种生理病理过程。最近研究表明,ERK5可促进肿瘤血管的生成并对肿瘤细胞生长起重要作用。因此,本文通过总结ERK5信号通路的作用原理及相关研究,为恶性肿瘤的诊断与治疗提供一种新的方法。

MAPK信号通路及STAT3、STAT5A/B在银屑病皮损中表达增高

目的检测寻常型银屑病患者皮损中p38丝裂原活化蛋白激酶(p38 MAPK)、细胞外调节蛋白激酶(ERK1/2)、c-Jun氨基末端激酶(JNK)、丝氨酸/苏氨酸激酶(Akt)、蛋白S6激酶1(p70S6k)、核因子-кB(NF-кB)、信号传导及转录激活因子3(STAT3)、信号传导及转录激活因子5(STAT5A/B)、钙反应元件结合蛋白(CREB)的蛋白表达情况,探讨这些因子在银屑病中的作用。方法收集27例寻常型银屑病患者皮损(银屑病组)及19例健康者皮肤组织(对照组),应用高灵敏MILLIPLEX MAP试剂及Luminex仪检测并定量9种因子的蛋白表达,比较两组之间的表达水平。结果 p38、ERK1/2、JNK、STAT3、STAT5A/B在银屑病组的表达量高于对照组,差异均有统计学意义(均P <0.05);STAT5A/B与p38、ERK1/2、JNK、STAT3呈正相关(均P <0.05)。结论 JNK、p38、ERK1/2、STAT3、STAT5A/B在寻常型银屑病中表达增高,且STAT5A/B与p38、ERK1/2、JNK、STAT3有正相关性,表明STAT5A/B与MAPK因子互相作用,可能共同参与银屑病发病机制。

ERK5信号通路研究现状

细胞外信号调节激酶5(extracellular signal regulated kinase, ERK5)是丝裂原活化蛋白激酶(mitogen activated protein kinase, MAPK)系统中的重要组成部分,也是MAPK信号转导通路中较新的一条通路,近几年备受人们关注。它可以被各种刺激因素激活,对细胞生存、增殖和分化有着重要作用,与血管发育、增殖等功能密切相关。本文从ERK5的来历、结构、性质、特点以及与肿瘤和非肿瘤疾病的关系,并对它以后的研究方向进行综述。

Circ_0053943 complexed with IGF2BP3 drives uveal melanoma progression via regulating N6-methyladenosine modification of Epidermal growth factor receptor

Numerous studies have characterized the critical role of circular RNAs(circRNAs)as regulatory factors in the progression of multiple cancers.However,the biological functions of circRNAs and their underlying molecular mechanisms in the progression of uveal melanoma(UM)remain enigmatic.In this study,we identified a novel circRNA,circ_0053943,through re-analysis of UM microarray data and quantitative RT-PCR.Circ_0053943 was found to be upregulated in UM and to promote the proliferation and metastatic ability of UM cells in both in vitro and in vivo settings.Mechanistically,circ_0053943 was observed to bind to the KH1 and KH2 domains of insulin-like growth factor 2 mRNA-binding protein 3(IGF2BP3),thereby enhancing the function of IGF2BP3 by stabilizing its target mRNA.RNA sequencing assays identified epidermal growth factor receptor(EGFR)as a target gene of circ_0053943 and IGF2BP3 at the transcriptional level.Rescue assays demonstrated that circ_0053943 exerts its biological function by stabilizing EGFR mRNA and regulating the downstream mitogen-activated protein kinase/extracellular signal-regulated kinase(MAPK/ERK)signaling pathway.Collectively,circ_0053943 may promote UM progression by stabilizing EGFR mRNA and activating the MAPK/ERK signaling pathway through the formation of a circ_0053943/IGF2BP3/EGFR RNA-protein ternary complex,thus providing a potential biomarker and therapeutic target for UM.

自制鼻咽解毒胶囊含药血清对鼻咽癌细胞系5-8F存活、凋亡的影响及其机制

目的观察自制鼻咽解毒胶囊含药血清对鼻咽癌细胞系5-8F存活、凋亡的影响,并探讨其机制。方法将对数生长期5-8F细胞分为8组,5%、10%、15%、20%、25%、30%鼻咽解毒胶囊含药血清组分别加入5%、10%、15%、20%、25%、30%鼻咽解毒胶囊含药血清,20%空白血清组加入20%不含药血清,对照组细胞正常培养,培养24、48 h,CCK-8法检测各组细胞存活率。将对数生长期5-8F细胞分为4组,低剂量组加入5%鼻咽解毒胶囊含药血清,中剂量组加入20%鼻咽解毒胶囊含药血清,高剂量组加入30%鼻咽解毒胶囊含药血清,阴性组细胞正常培养,培养24 h,流式细胞术检测细胞凋亡率,RT-qPCR法检测细胞中K-RAS、RAF mRNA相对表达量,Western blot法检测细胞中K-RAS、RAF、p-ERK1/2蛋白相对表达量。结果与对照组比较,20%含药血清组、25%含药血清组、30%含药血清组培养24 h及48 h的细胞存活率降低(P均<0.05);与20%空白血清组比较,25%含药血清组培养48 h和30%含药血清组培养24、48 h的细胞存活率降低(P均<0.05);与同组24 h比较,30%含药血清组培养48 h的细胞存活率降低(P<0.05)。与阴性组比较,低剂量组、中剂量组、高剂量组凋亡率升高(P均<0.05);与低剂量组比较,中剂量组、高剂量组细胞凋亡率升高(P均<0.05);与中剂量组比较,高剂量组细胞凋亡率升高(P<0.05)。与阴性组比较,低剂量组、中剂量组、高剂量组的K-RAS、RAF mRNA相对表达量降低(P均<0.05);与低剂量组比较,中剂量组、高剂量组K-RAS、RAF mRNA相对表达量降低(P均<0.05);与中剂量组比较,高剂量组K-RAS、RAF mRNA相对表达量降低(P均<0.05)。与阴性组比较,高剂量组K-RAS蛋白、RAF蛋白、p-ERK1/2蛋白相对表达量降低,中剂量组的K-RAS、RAF蛋白相对表达量降低,低剂量组RAF蛋白相对表达量降低(P均<0.05);与低剂量组比较,高剂量组K-RAS、RAF、p-ERK1/2蛋白相对表达量及中剂量组K-RAS、p-ERK1/2蛋白相对表达量降低(P均<0.05);与中剂量组比较,高剂量组K-RAS蛋白相对表达量降低(P<0.05)。结论自制鼻咽解毒胶囊含药血清能抑制5-8F细胞存活,并促进细胞凋亡,且呈剂量依赖性,尤以30%鼻咽解毒胶囊含药血清剂量为最佳,作用机制可能与其可抑制MAPK/ERK信号通路有关。

Estrogen and insulin synergistically promote endometrial cancer progression via crosstalk between their receptor signaling pathways

Objective: Despite evidence that estrogens and insulin are involved in the development and progression of many cancers, their synergistic role in endometrial carcinoma(EC) has not been analyzed yet.Methods: Here, we investigated how estrogens act synergistically with insulin to promote EC progression. Cell growth in vitro and in vivo, effects of estradiol and insulin on apoptosis and cell cycle distribution, and expression and activation of estrogen receptor(ER), insulin receptor(InsR), and key proteins in the PI3K and MAPK pathways were examined after combined stimulation with estradiol and insulin.Results: Compared to EC cells treated with estradiol or insulin alone, those treated with both estradiol and insulin exhibited stronger stimulation. Estradiol significantly induced phosphorylation of InsR-β and IRS-1, whereas insulin significantly induced phosphorylation of ER-α. In addition, treatment with both insulin and estradiol together significantly increased the expression and phosphorylation of Akt, MAPK, and ERK. Notably, InsR-β inhibition had a limited effect on estradiol-dependent proliferation,cell cycle, and apoptosis, whereas ER-α inhibition had a limited insulin-dependent effect, in EC cell lines. Insulin and estradiol individually and synergistically promoted EC xenograft growth in mice.Conclusions: Estrogen and insulin play synergistic roles in EC carcinogenesis and progression by activating InsR-β and ER-α,promoting a crosstalk between them, and thereby resulting in the activation of downstream PI3K/Akt and MAPK/ERK signaling pathways.

氧化应激在鱼藤素致SH-SY5Y细胞神经毒性中的作用

目的研究氧化应激与鱼藤素致神经毒性的相关性,为后续鱼藤素的结构改造和联合用药提供机制基础。方法将鱼藤素(1.56~100μmol·L-1)与SH-SY5Y细胞共孵育培养24~72 h,采用CCK-8法测定细胞存活率;比色法测定乳酸脱氢酶(lactate dehydrogenase,LDH)漏出量、丙二醛(malondialdehyde,MDA)含量、谷胱甘肽过氧化物酶(glutathione peroxidase,GPx)和超氧化物歧化酶(superoxide dismutase,SOD)的活力;流式细胞术检测活性氧(reactive oxygen species,ROS)含量;免疫印迹法检测细胞中MEK、EGF、RAS、CREB蛋白的表达情况。结果鱼藤素对SH-SY5Y细胞增殖有抑制作用,且呈浓度和时间依赖性(P<0.05)。鱼藤素损伤细胞后,LDH漏出量、MDA和ROS含量明显增加,GPx和SOD的活力下降(P<0.05)。同时MAPK/ERK信号通路中MEK、EGF、RAS、CREB蛋白水平出现不同程度的下调。结论鱼藤素致SH-SY5Y神经细胞的损伤与氧化应激密切相关,MAPK/ERK信号通路可能在其中起介导作用。

CD5 expression promotes IL-10 production through activation of the MAPK/Erk pathway and upregulation of TRPC1 channels in B lymphocytes

CD5 is constitutively expressed on T cells and a subset of mature normal and leukemic B cells in patients with chronic lymphocytic leukemia(CLL).Important functional properties are associated with CD5 expression in B cells,including signal transducer and activator of transcription 3 activation,IL-10 production and the promotion of B-lymphocyte survival and transformation.However,the pathway(s)by which CD5 influences the biology of B cells and its dependence on B-cell receptor(BCR)co-signaling remain unknown.In this study,we show that CD5 expression activates a number of important signaling pathways,including Erk1/2,leading to IL-10 production through a novel pathway independent of BCR engagement.This pathway is dependent on extracellular calcium(Ca2+)entry facilitated by upregulation of the transient receptor potential channel 1(TRPC1)protein.We also show that Erk1/2 activation in a subgroup of CLL patients is associated with TRPC1 overexpression.In this subgroup of CLL patients,small inhibitory RNA(siRNA)for CD5 reduces TRPC1 expression.Furthermore,siRNAs for CD5 or for TRPC1 inhibit IL-10 production.These findings provide new insights into the role of CD5 in B-cell biology in health and disease and could pave the way for new treatment strategies for patients with B-CLL.

Hypoxia-inducible factor-1α–mediated upregulation of CD99 promotes the proliferation of placental mesenchymal stem cells by regulating ERK1/2

BACKGROUND As human placenta-derived mesenchymal stem cells(hP-MSCs)exist in a physiologically hypoxic microenvironment,various studies have focused on the influence of hypoxia.However,the underlying mechanisms remain to be further explored.AIM The aim was to reveal the possible mechanisms by which hypoxia enhances the proliferation of hP-MSCs.METHODS A hypoxic cell incubator(2.5%O2)was used to mimic a hypoxic microenvironment.Cell counting kit-8 and 5-ethynyl-20-deoxyuridine incorporation assays were used to assay the proliferation of hP-MSCs.The cell cycle was profiled by flow cytometry.Transcriptome profiling of hP-MSCs under hypoxia was performed by RNA sequencing.CD99 mRNA expression was assayed by reverse transcription-polymerase chain reaction.Small interfering RNA-mediated hypoxia-inducible factor 1α(HIF-1α)or CD99 knockdown of hP-MSCs,luciferase reporter assays,and the ERK1/2 signaling inhibitor PD98059 were used in the mechanistic analysis.Protein expression was assayed by western blotting;immunofluorescence assays were conducted to evaluate changes in expression levels.RESULTS Hypoxia enhanced hP-MSC proliferation,increased the expression of cyclin E1,cyclin-dependent kinase 2,and cyclin A2,and decreased the expression of p21.Under hypoxia,CD99 expression was increased by HIF-1α.CD99-specific small interfering RNA or the ERK1/2 signaling inhibitor PD98059 abrogated the hypoxia-induced increase in cell proliferation.CONCLUSION Hypoxia promoted hP-MSCs proliferation in a manner dependent on CD99 regulation of the MAPK/ERK signaling pathway in vitro.

Tobacco-specific Carcinogen 4-(Methylnitrosoamino)-1-(3-pyridyl)-1-butanone(NNK) Activating ERK1/2 MAP Kinases and Stimulating Proliferation of Human Mammary Epithelial Cells

Cigarette smoking is correlated with the development of various cancers. 4- （Methylnitresoamino） -1- （3-pyridyl） - 1-butanone（NNK） is one of the major tobacco-specific carcinogens in the cigarette smoke, which increases the risk of breast cancer. In the present study, it was demonstrated that NNK rapidly activated ERK1 and ERK2 MAP kinases in human normal mammary epithelial cells. It was found that there are two different routes for the activation of ERK1/2 with NNK. One is from nicotinic receptor nAchR to MEK1/2, and the other is from tyrosine kinase containing receptor to MEK1/2. The tobacco-specific carcinogen NNK shows a strong proliferative effect on normal human mammary epithelial cells and cancer mammary epithelial cells.

ERK5 MAPK信号转导通路研究进展

MAPK信号转导通路是一条关键的调节细胞增生和凋亡的通路。MAPK信号转导通路的异常与多种肿瘤或增殖性疾病关系密切。因此,MAPK是潜在的治疗分子靶。目前已鉴定了4条MAPK信号转导通路：ERK1／2、JNK、P38和ERK5。其中ERK5信号途径是相对较新的一条通路。本文拟从ERK5信号转导通路的性质特点、功能以及与人类疾病关系各方面分别加以综述。

CAFs调控MAPK/ERK5通路抑制结直肠癌HT-29细胞凋亡

为探讨肿瘤相关成纤维细胞(CAFs)对结直肠癌细胞增殖和凋亡的影响及分子机制,本研究通过组织贴壁法从结直肠癌组织中分离CAFs,并验证CAFs中α-SMA的表达;通过Transwell建立CAFs和结直肠癌细胞系HT-29共培养系统,CCK8检测结直肠癌HT-29细胞活力;流式细胞术检测HT-29细胞凋亡率;通过实时荧光定量PCR和Western blotting检测结直肠癌细胞中VEGF的mRNA和蛋白表达以及ERK5磷酸化水平。与对照NFs相比,α-SMA在结CAFs中表达显著增加(p<0.01)。CCK8结果表明CAFs促进结直肠癌细胞的增殖;流式结果显示CAFs能抑制细胞凋亡;Real-time RT-PCR和Western blotting结果显示CAFs促进结直肠癌细胞内VEGF的mRNA和蛋白表达,并促进ERK5磷酸化。本研究初步表明,CAFs激活MAPK/ERK5通路和VEGF的表达,可促进结直肠癌HT-29细胞增殖。