VARIATION AND SIGNIFICANCE OF C-MYC PROTEIN IN RAT CARDIAC VOLUME-OVERLOAD HYPERTROPHY

Objective To investigate the change of c-myc protein, which was chosen as the response indicator to volume-overload. Methods The time and spatial course of c-myc protein expression on the model of rat cardiac volume-overload hypertrophy was examined by immunohistochemical study. Results The immunohistochemical study indicated the expression of c-myc protein was increased obviously at 4-6 hours (62.73%) than that of control (45.41%, P<0.01) after the volume-overload, then decreased gradually along with development of volume-overload hypertrophy and was decreased extremely at 5 months(r=-0.514,P<0.01).Conclusion There are disorders in the signal transduction pathways governing the hypertrophic response of cardiomyocytes in hypertrophic myocardium. C-myc gene and the product of it may be only the promoter gene of myocardial hypertrophy. Once switching on,c-myc gene and the product of it do not act anymore;While it may be that c-myc gene and the product of it increased following with myocardial hypertrophy, and have not direct relation to the occurrence and development of myocardial hypertrophy.

INHIBITION OF C-MYC PROTEIN EXPRESSION AND CELL PROLIFERATION IN HL-60 CELLS BY ANTISENSE TRANSCRIPTS TO c-myc

The human promyelocytic cell line HL-60 overexpresses the c-myc protooncogene. Plasmid pDACx carrying antisense human c-myc DNA and neo gene was introduced into HL-60 cells with lipofectin reagent. Upon DNA entering the tar-geted celis and expression of antisense transcripts to c-myc, C-MYC protein level, cell proliferation and colony-forming potentiality were all definitely inhibited.

c-Myc、CDK12在胃癌组织中的表达及临床意义

目的 探讨胃癌组织中c-Myc、细胞周期蛋白依赖性激酶12(CDK12)表达及其与患者临床特征及预后的关系。方法 收集80例胃癌患者的胃癌组织和癌旁组织标本,采用免疫组化法检测标本中的c-Myc、CDK12表达水平。比较胃癌组织和癌旁组织中c-Myc、CDK12阳性表达情况;分析胃癌组织中c-Myc、CDK12阳性表达与患者临床病理特征的关系;分析c-Myc与CDK12阳性表达的相关性,胃癌组织中c-Myc、CDK12阳性表达与胃癌患者预后的关系。结果 胃癌组织中c-Myc、CDK12阳性表达率(77.5%、87.5%)均明显高于癌旁组织(13.8%、15.0%)(P<0.05)。不同年龄、性别、肿瘤最大直径患者胃癌组织中c-Myc、CDK12阳性表达率比较差异无统计学意义(P>0.05);中低分化、Ⅲ~Ⅳ期、侵犯浆膜、有淋巴结转移患者胃癌组织中c-Myc和CDK12阳性表达率分别为88.0%、87.0%、88.9%、90.0%和94.0%、92.6%、97.2%、100.0%,均明显高于高分化、Ⅰ~Ⅱ期、未侵犯浆膜、无淋巴结转移患者胃癌组织的60.0%、57.7%、68.2%、70.0%和76.7%、76.9%、79.5%、80.0%(P<0.05)。相关分析发现,c-Myc、CDK12在胃癌组织中的表达呈正相关性(r=0.487,P=0.016<0.05)。胃癌组织中c-Myc、CDK12阳性患者的3年生存率分别为19.4%、21.4%,均明显低于c-Myc、CDK12阴性患者的55.6%、70.0%(P<0.05)。结论 c-Myc、CDK12在胃癌组织中异常高表达,两者呈正相关性,并与肿瘤的TNM分期、分化程度、肿瘤侵袭深度及淋巴结转移有关,对患者的预后有明显影响,通过检测两者水平可能评估胃癌患者的预后。

胃癌模型大鼠胃黏膜组织Cyclin D1、c-Myc、CKIT的表达意义及其与胃癌病变程度的相关性

目的探讨胃癌模型大鼠胃黏膜组织细胞周期蛋白D1(cyclinD1)、c-Myc、CKIT的表达意义及其与胃癌病变程度的相关性。方法选择48只健康成年雌性大鼠,按照随机数字表法将其分为对照组、研究1组、研究2组、研究3组,每组各12只。研究1组、研究2组、研究3组均制备成胃癌模型。对照组给予等量0.9%氯化钠溶液,第24周处死取材;研究1组、研究2组、研究3组制备成胃癌大鼠后分别于第8、16、24周取材。分析各组大鼠一般情况及胃黏膜组织病理切片,采用蛋白质印迹法检测胃黏膜组织Cyclin D1、c-Myc、CKIT蛋白的表达,采用逆转录聚合酶链式反应(RT-PCR)法测定胃黏膜组织Cyclin D1、c-Myc、CKIT mRNA的表达,采用Spearman分析法测定胃黏膜组织Cyclin D1、c-Myc、CKIT表达与胃癌病变程度相关性。结果对照组大鼠胃黏膜完整正常,外膜层、肌层、黏膜下层、黏膜层等结构清晰,且无炎症细胞浸润;研究1组大鼠胃黏膜组织与对照组大鼠接近,不存在炎症细胞,且黏膜腺体结构基本正常;研究2组大鼠胃黏膜组织存在破损,细胞核变大,基底部部分腺体细胞形态异常,存在轻度异型性,为早期胃癌;研究3组大鼠胃黏膜组织增加破损,核质比变大,细胞形态不规则,部分腺体存在扩张,黏膜下层及肌层存在炎症细胞浸润,为胃癌进展期。研究1组、研究2组、研究3组胃黏膜组织Cyclin D1、c-Myc、CKIT蛋白均呈显著高于对照组,差异均有统计学意义(P<0.05),胃黏膜组织Cyclin D1、c-Myc、CKIT蛋白在研究1组、研究2组、研究3组中逐渐升高趋势。研究1组、研究2组、研究3组胃黏膜组织Cyclin D1、c-Myc、CKIT mRNA均呈显著高于对照组,差异均有统计学意义(P<0.05),胃黏膜组织Cyclin D1、c-Myc、CKIT mRNA在研究1组、研究2组、研究3组中逐渐升高趋势。采用Spearman相关性结果分析显示,胃黏膜组织Cyclin D1、c-Myc、CKIT表达与胃癌病变程度呈正相关(r=0.382、0.781、0.993,均P<0.001)。结论胃癌模型大鼠胃黏膜组织Cyclin D1、c-Myc、CKIT呈高表达,其与胃癌病变程度密切相关。

鳜弹状病毒N蛋白与鳜c-Myc互作调控谷氨酰胺代谢机制

为了研究鳜弹状病毒(SCRV)如何调控鳜c-Myc(Sc-c-Myc)进而调控谷氨酰胺代谢的分子机制,本研究通过免疫共沉淀联合蛋白质谱寻找可能与Sc-c-Myc互作的病毒蛋白,初步分析确定为核衣壳蛋白(N蛋白);Co-IP结果显示,SCRV的N蛋白与Sc-c-Myc存在相互作用。通过PCR扩增获得了带有Flag标签序列的SCRV-N基因的ORF片段,并构建了SCRV-N蛋白过表达载体pcDNA-N-Flag;将pcDNA-N-Flag质粒转染鳜脑组织细胞系(CPB细胞系),荧光共定位结果显示,Sc-c-Myc与SCRV-N在细胞质内存在共定位现象;通过逆转录实时定量PCR(RT-qPCR)和免疫印记(Western blot)检测转染pcDNA-N-Flag的CPB细胞系中Sc-c-Myc及谷氨酰胺代谢通路关键酶(GLS1、GDH和IDH2)的表达变化,发现Sc-c-Myc、GLS1的转录水平和蛋白水平均显著上调。综上表明,SCRV的N蛋白与Sc-c-Myc互作促进Sc-c-Myc的表达,进而调控宿主细胞谷氨酰胺代谢途径,为SCRV防控提供了新的靶点。

猫CDH1基因在过表达c-MYC成纤维细胞中的表达变化及生物信息学分析

[目的]试验旨在研究骨髓细胞瘤病毒癌基因同源物(myelocytomatosis viral oncogene homolog, c-MYC)对猫成纤维细胞的影响及其与E-钙黏蛋白(cadherin 1,CDH1)基因表达和分子特性的关系,为将其应用于猫肿瘤疾病防治和组织损伤修复提供依据。[方法]通过组织贴壁法对猫胎儿成纤维细胞进行分离培养,利用电转仪将PB-TRE-c-MYC质粒转染至细胞并观察细胞形态,利用实时荧光定量PCR检测CDH1基因的表达情况,并通过生物信息学软件分析CDH1蛋白的理化性质和结构特征。[结果]过表达c-MYC导致细胞形态发生变化,从间质细胞的长梭型向上皮细胞的鹅卵石状发生转变,且使上皮细胞标志基因CDH1的表达极显著上调(P<0.01)。生物信息学分析显示,猫CDH1蛋白有881个氨基酸,其中含量最多的是亮氨酸,定位于细胞膜,存在4个CA结构域,介导细胞与细胞的接触,属于亲水性的酸性蛋白,主要由无规则卷曲组成,可能存在由Sec易位子转运并被信号肽酶Ⅰ(Sec/SPⅠ)切割的信号肽位点。[结论]猫CDH1基因的表达可被外源性重编程因子c-MYC激活,其编码的钙黏蛋白可促进猫胎儿成纤维细胞的间质-上皮转化,以抑制细胞癌化。

基于ERK介导C-Myc/PD-L1协同作用探讨参芪抑瘤方联合顺铂对H22肝癌荷瘤小鼠的抑瘤机制

目的:探讨参芪抑瘤方联合顺铂经ERK介导C-Myc/PD-L1相协途径对H22肝癌荷瘤小鼠的抑瘤作用及其机制。方法:60只SPF级雄性昆明小鼠,采用随机数字表法取10只小鼠作为空白组,其余50只小鼠复制H22肝癌荷瘤小鼠模型,模型复制成功后将模型小鼠随机分为模型组、顺铂组[2.5×10^(-3) g/(kg·3 d)]、参芪抑瘤方低[13.515 g/(kg·d)]、中[27.030 g/(kg·d)]、高剂量[54.060 g/(kg·d)]联合顺铂[2.5×10^(-3) g/(kg·3 d)]组,每组10只,治疗13 d,末次给药24 h后,麻醉处死小鼠,测定小鼠肿瘤抑制率和脾指数、胸腺指数;HE染色观察小鼠肿瘤组织病理学变化;ELISA试剂盒检测肿瘤组织匀浆液中EGF、IFN-γ含量;IHC法和Western blot法检测肿瘤组织中p-ERK1/2、C-Myc、PD-L1蛋白表达;RT-PCR法检测肿瘤组织中ERK、C-Myc、PD-L1mRNA表达水平。结果:与空白组相比,模型组小鼠平均体质量和脾脏指数均降低(P<0.05);与模型组相比,各治疗组肿瘤抑制效果明显,且参芪抑瘤方联合顺铂组以剂量依赖性方式抑制肝癌小鼠肿瘤生长,提高小鼠平均体质量和脾指数、胸腺指数,促进肿瘤细胞坏死,增加坏死面积,降低肿瘤组织中EGF和IFN-γ含量以及p-ERK1/2、C-Myc、PD-L1蛋白表达和ERK、C-Myc、PD-L1 mRNA表达(P<0.05);与顺铂组相比,参芪抑瘤方中、高剂量联合顺铂组治疗效果显著,差异具有统计学意义(P<0.05)。结论:参芪抑瘤方联合顺铂能有效抑制H22肝癌荷瘤小鼠的肿瘤生长,显著下调肿瘤组织中C-Myc与PD-L1蛋白表达,该机制可能通过调控ERK信号通路相关蛋白表达发挥抑瘤作用。

在口腔表皮样癌细胞中c-myc对GS和GLS表达的调控以及对癌瘤生长的裸鼠体内实验研究

目的:用动物实验模型探讨人口腔表皮样癌细胞中c-myc与谷氨酰胺酶(GLS)、谷氨酰胺合成酶(GS)间的相关性。方法:免疫组化检测口腔癌临床样本中c-myc、GLS、GS表达。建立c-myc稳定高表达的KB细胞模型,并移植入裸鼠体内以建立裸鼠成瘤模型,细胞和裸鼠各分为3组(n=6),分别为正常对照组、空载体转染细胞组和c-myc过表达细胞组,观察肿瘤生长;免疫组化检测肿瘤中c-myc、 GLS、 GS的表达情况。结果:c-myc、 GLS、 GS在口腔癌临床样本中高表达;在c-myc高表达细胞模型中c-myc mRNA表达水平显著高于空载体对照组;在动物实验中,随着时间的延长,各组裸鼠成瘤模型均形成肿瘤,c-myc过表达组肿瘤体积及重量增加更为显著(P<0.01);c-myc过表达组瘤组织样本中GLS及GS表达显著高于空载体组和对照组(P<0.01)。结论:在口腔表皮样癌细胞中,c-myc高表达,并使GLS、GS表达升高。

Melatonin inhibits ESCC tumor growth by mitigating the HDAC7/β-catenin/c-Myc positive feedback loop and suppressing the USP10-maintained HDAC7 protein stability

Background:Melatonin,a natural hormone secreted by the pineal gland,has been reported to exhibit antitumor properties through diverse mechanisms of action.However,the oncostatic function of melatonin on esophageal squamous cell carcinoma(ESCC) remains elusive.This study was conducted to investigate the potential effect and underlying molecular mechanism of melatonin as single anticancer agent against ESCC cells.Methods:ESCC cell lines treated with or without melatonin were used in this study.In vitro colony formation and 5-Ethynyl-2’-deoxyuridine(EdU) incorporation assays,and nude mice tumor xenograft model were used to confirm the proliferative capacities of ESCC cells.RNA-seq,qPCR,Western blotting,recombinant lentivirus-mediated target gene overexpression or knockdown,plasmids transfection and co-IP were applied to investigate the underlying molecular mechanism by which melatonin inhibited ESCC cell growth.IHC staining on ESCC tissue microarray and further survival analyses were performed to explore the relationship between target genes’ expression and prognosis of ESCC.Results:Melatonin treatment dose-dependently inhibited the proliferative ability and the expression of histone deacetylase 7(HDAC7),c-Myc and ubiquitin-specific peptidase 10(USP10) in ESCC cells(P<0.05).The expressions of HDAC7,c-Myc and USP10 in tumors were significantly higher than the paired normal tissues from 148 ESCC patients(P<0.001).Then,the Kaplan-Meier survival analysis suggested that ESCC patients with high HDAC7,c-Myc or USP10levels predicted worse overall survival(log-rank P<0.001).Co-IP and Western blotting further revealed that HDAC7physically deacetylated and activated β-catenin thus promoting downstream target c-Myc gene transcription.Notably,our mechanistic study validated that HDAC7/β-catenin/c-Myc could form the positive feedback loop to enhance ESCC cell growth,and USP10 could deubiquitinate and stabilize HDAC7 protein in the ESCC cells.Additionally,we verified that inhibition of the HDAC7/β-catenin/c-Myc axis and USP10/HDAC7 pathway mediated the anti-proliferative action of melatonin on ESCC cells.Conclusions:Our findings elucidate that melatonin mitigates the HDAC7/β-catenin/c-Myc positive feedback loop and inhibits the USP10-maintained HDAC7 protein stability thus suppressing ESCC cell growth,and provides the reference for identifying biomarkers and therapeutic targets for ESCC.

Essential proteins identification method based on four-order distances and subcellular localization information

Essential proteins are inseparable in cell growth and survival. The study of essential proteins is important for understanding cellular functions and biological mechanisms. Therefore, various computable methods have been proposed to identify essential proteins. Unfortunately, most methods based on network topology only consider the interactions between a protein and its neighboring proteins, and not the interactions with its higher-order distance proteins. In this paper, we propose the DSEP algorithm in which we integrated network topology properties and subcellular localization information in protein–protein interaction(PPI) networks based on four-order distances, and then used random walks to identify the essential proteins. We also propose a method to calculate the finite-order distance of the network, which can greatly reduce the time complexity of our algorithm. We conducted a comprehensive comparison of the DSEP algorithm with 11 existing classical algorithms to identify essential proteins with multiple evaluation methods. The results show that DSEP is superior to these 11 methods.

5-Fluorouracil dose escalation generated desensitized colorectal cancer cells with reduced expression of protein methyltransferases and no epithelial-to-mesenchymal transition potential

Background:Colorectal cancer(CRC)is one of the most frequently diagnosed cancers.In many cases,the poor prognosis of advanced CRC is associated with resistance to treatment with chemotherapeutic drugs such as 5-Fluorouracil(5-FU).The epithelial-to-mesenchymal transition(EMT)and dysregulation in protein methylation are two mechanisms associated with chemoresistance in many cancers.This study looked into the effect of 5-FU dose escalation on EMT and protein methylation in CRC.Materials and Methods:HCT-116,Caco-2,and DLD-1 CRC cell lines were exposed to dose escalation treatment of 5-FU.The motility and invasive potentials of the cells before and after treatment with 5-FU were investigated through wound healing and invasion assays.This was followed by aWestern blot which analyzed the protein expressions of the epithelial marker E-cadherin,mesenchymal marker vimentin,and the EMT transcription factor(EMTTF),the snail family transcriptional repressor 1(Snail)in the parental and desensitized cells.Western blotting was also conducted to study the protein expressions of the protein methyltransferases(PMTs),Euchromatic histone lysine methyltransferase 2(EHMT2/G9A),protein arginine methyltransferase(PRMT5),and SET domain containing 7/9(SETD7/9)along with the global lysine and arginine methylation profiles.Results:The dose escalation method generated 5-FU desensitized CRC cells with distinct morphological features and increased tolerance to high doses of 5-FU.The 5-FU desensitized cells experienced a decrease in migration and invasion when compared to the parental cells.This was reflected in the observed reduction in E-cadherin,vimentin,and Snail in the desensitized cell lines.Additionally,the protein expressions of EHMT2/G9A,PRMT5,and SETD7/9 also decreased in the desensitized cells and global protein lysine and arginine methylation became dysregulated with 5-FU treatment.Conclusion:This study showed that continuous,dose-escalation treatment of 5-FU in CRC cells generated 5-FU desensitized cancer cells that seemed to be less aggressive than parental cells.

Near Infrared Spectroscopy (NIRS) Model-Based Prediction for Protein Content in Cowpea

Cowpea (Vigna unguiculata L. Walp) is a multi-purpose legume with high quality protein for human consumption and livestock. The objective of this work was to develop near-infrared spectroscopy (NIRS) prediction models to estimate protein content in cowpea. A total of 116 cowpea breeding lines with a wide range of protein contents (19.28 % to 32.04%) were selected to build the model using whole seed and ground seed samples. Partial least-squares discriminant analysis (PLS-DA) regression technique with different pre-treatments (derivatives, standard normal variate, and multiplicative scatter correction) were carried out to develop the protein prediction model. Results showed: 1) spectral plots of both the whole seed and ground seed showed higher spectral scatter at higher wavelengths (>1450 nm), 2) data pre-processing affects prediction accuracy for bot whole seed and ground seed samples, 3) prediction using ground seed samples (0.64 R2 0.85) is better than the whole seed (0.33 R2 0.78), and 4) the data pre-processing second derivative with standard normal variate has the best prediction (R2_whole seed = 0.78, R2_ground seed = 0.85). The results will be of interest in cowpea breeding programs aimed at improving total seed protein content.

Food-derived protein hydrolysates and peptides:anxiolytic and antidepressant activities,characteristics,and mechanisms

Globally,the prevalence of anxiety and depression has reached epidemic proportions.Food-derived protein hydrolysates and peptides delivered through dietary supplementation can avoid the negative risks associated with traditional pharmaceuticals while delivering superior anxiolytic and antidepressant effects.This review summarizes current research on food-derived anxiolytic and antidepressant protein hydrolysates and peptides,and subsequently analyses their physicochemical characteristics and elaborates on their mechanisms.The aim of this work is to contribute to the in-depth study and provide a theoretical foundation for the development of related products to better serve patients with anxiety and depression.

Activated Protein C Resistance in Patients with Pre-Eclampsia in Lagos, Nigeria

Background: Preeclampsia is reported to complicate 2% - 8% of pregnancies globally and is an important cause of maternal and perinatal morbidity and mortality. The aetiology and pathogenesis are still poorly understood and substantial improvement has not been made in the prediction, prevention and treatment of the disease. Objective: To compare the frequency of activated protein C resistance (APC-R) in patients with pre-eclampsia to that of normotensive pregnant women and to determine the correlation between activated protein ratio (APC-ratio) and the severity of pre-eclampsia. Methodology: A cross-sectional study was carried out in 100 pre-eclamptic patients and 100 normotensive pregnant controls. The APC-ratio was determined using the modified activated partial thromboplastin time. Study participants with APC-ratio of less than 2.0 were defined as having APC-R. Data was analyzed using SPSS version 22.0. Results: Mean APC-ratio was significantly lower in pre-eclamptics (2.89 ± 1.70) compared to normotensive pregnant women (3.57 ± 1.06) (p = 0.0008) and the levels were also higher in mild (2.95 ± 1.15) compared to severe pre-eclamptics (2.62 ± 1.14). The frequency of APC-R was 26% among women with pre-eclampsia compared to 4% among normotensive controls (p = 0.000). Among 100 pre-eclamptic women 7 (21.2%) out of 33 with mild pre–eclampsia had APC-R, while 19 (28.4%) out of 67 with severe pre-eclampsia had APC-R. APC-ratio had a significant negative correlation with mean arterial blood pressure (r = −0.324;p = 0.000) and proteinuria (r = −0.379;p = 0.000) among study participants. Conclusion: The frequency of activated protein c resistance is significantly higher in pre-eclamptics compared to normotensive pregnant women and this is more pronounced in those with severe pre-eclampsia compared with those with mild disease. APC-R may therefore be used as a marker of severity in the disease.

GmSTF accumulation mediated by DELLA protein GmRGAs contributes to coordinating light and gibberellin signaling to reduce plant height in soybean

Plant height influences plant architecture,lodging resistance,and yield performance.It is modulated by gibberellic acid(GA)metabolism and signaling.DELLA proteins,acting as central repressors of GA signaling,integrate various environmental and hormonal signals to regulate plant growth and development in Arabidopsis.We examined the role of two DELLA proteins,GmRGAa and GmRGAb,in soybean plant height control.Knockout of these proteins led to longer internodes and increased plant height,primarily by increasing cell elongation.GmRGAs functioned under different light conditions,including red,blue,and far-red light,to repress plant height.Interaction studies revealed that GmRGAs interacted with the blue light receptor GmCRY1b.Consistent with this,GmCRY1b partially regulated plant height via GmRGAs.Additionally,DELLA proteins were found to stabilize the protein GmSTF1/2,a key positive regulator of photomorphogenesis.This stabilization led to increased transcription of GmGA2ox-7b and subsequent reduction in plant height.This study enhances our understanding of DELLA-mediated plant height control,offering Gmrgaab mutants for soybean structure and yield optimization.

A Budd-Chiari Syndrome Due to C Protein Deficiency: A Case Report at YaoundéGeneral Hospital (Cameroon)

Primary Budd-Chiari syndrome (BCS) is a spontaneously fatal disease characterized by an obstruction of the hepatic venous outflow tract due to thrombosis or a primary disease of the venous wall. The primary form of BCS is extremely rare. This is a disease mainly affecting young adults of both sexes. Clinical manifestations are variable;they can be asymptomatic, acute, or subacute but mostly chronic. Several causes have been identified, such as myeloproliferative syndrome, antiphospholipid syndrome, paroxysmal nocturnal hemoglobinuria, and inherited thrombotic disorders. Data on primary BCS in Sub-Saharan Africa is rare as most publications available are case reports. In these reports, the causes are unknown with poor prognosis in most cases often leading to patient death. We herein present a case report of a male patient diagnosed with a primary BCS at Yaoundé General Hospital (Cameroon) caused by a Protein C deficiency who presented with ascites decompensating liver cirrhosis. Treatment was based on anticoagulants, diuretics and laxatives administration. Two years after the diagnosis, the patient is alive with clinical and paraclinical improvement.

The physiological role of the unfolded protein response in the nervous system

The unfolded protein response(UPR)is a cellular stress response pathway activated when the endoplasmic reticulum,a crucial organelle for protein folding and modification,encounters an accumulation of unfolded or misfolded proteins.The UPR aims to restore endoplasmic reticulum homeostasis by enhancing protein folding capacity,reducing protein biosynthesis,and promoting protein degradation.It also plays a pivotal role in coordinating signaling cascades to determine cell fate and function in response to endoplasmic reticulum stress.Recent research has highlighted the significance of the UPR not only in maintaining endoplasmic reticulum homeostasis but also in influencing various physiological processes in the nervous system.Here,we provide an overview of recent findings that underscore the UPR’s involvement in preserving the function and viability of neuronal and myelinating cells under physiological conditions,and highlight the critical role of the UPR in brain development,memory storage,retinal cone development,myelination,and maintenance of myelin thickness.

LncRNA CDC6通过抑制c-Myc表达调节肺癌细胞增殖、凋亡和上皮间质转化

目的探讨LncRNA CDC6(CDC6)对肺癌细胞增殖、上皮间质转化(epithelial-mesenchymal transition,EMT)和凋亡的影响及其作用机制。方法RT-qPCR检测肺癌组织和细胞中CDC6和c-Myc的mRNA水平,并分析CDC6和c-Myc mRNA水平与患者临床指标的相关性。随后,通过CDC6-siRNA和pcDNA-CDC6转染,或CDC6-siRNA和pcDNA-c-Myc共转染肺癌细胞;MTT法检测细胞增殖能力;流式细胞术检测细胞凋亡;Western Blotting检测增殖、凋亡及EMT相关蛋白的表达。结果LncRNA CDC6在肺癌组织和细胞系中高表达(P<0.05)。CDC6和c-Myc mRNA水平与肺癌的病理分型、TNM分期、分化程度以及淋巴结的转移密切相关。沉默CDC6抑制肺癌细胞增殖,促进细胞凋亡,降低增殖相关蛋白以及EMT相关蛋白表达水平,促进促凋亡蛋白Bax表达,抑制抗凋亡蛋白Bcl-2表达(P<0.05)。过表达CDC6促进肺癌细胞增殖,抑制细胞凋亡,上调增殖相关蛋白以及EMT相关蛋白表达,减少促凋亡蛋白Bax水平,增加抗凋亡蛋白Bcl-2水平(P<0.05)。过表达c-Myc逆转了沉默CDC6对A549细胞增殖、凋亡以及EMT相关蛋白表达的影响。结论LncRNA CDC6通过调控c-Myc促进EMT过程及肺癌细胞的增殖能力,抑制细胞凋亡。

Surviving winter on the Qinghai-Xizang Plateau:Extensive reversible protein phosphorylation plays a dominant role in regulating hypometabolism in hibernating Nanorana parkeri

Changes in protein abundance and reversible protein phosphorylation(RPP)play important roles in regulating hypometabolism but have never been documented in overwintering frogs at high altitudes.To test the hypothesis that protein abundance and phosphorylation change in response to winter hibernation,we conducted a comprehensive and quantitative proteomic and phosphoproteomic analysis of the liver of the Xizang plateau frog,Nanorana parkeri,living on the Qinghai-Xizang Plateau.In total,5170 proteins and 5695 phosphorylation sites in 1938 proteins were quantified.Based on proteomic analysis,674 differentially expressed proteins(438 up-regulated,236 down-regulated)were screened in hibernating N.parkeri versus summer individuals.Functional enrichment analysis revealed that higher expressed proteins in winter were significantly enriched in immune-related signaling pathways,whereas lower expressed proteins were mainly involved in metabolic processes.A total of 4251 modified sites(4147 up-regulated,104 down-regulated)belonging to 1638 phosphoproteins(1555 up-regulated,83 down-regulated)were significantly changed in the liver.During hibernation,RPP regulated a diverse array of proteins involved in multiple functions,including metabolic enzymatic activity,ion transport,protein turnover,signal transduction,and alternative splicing.These changes contribute to enhancing protection,suppressing energy-consuming processes,and inducing metabolic depression.Moreover,the activities of phosphofructokinase,glutamate dehydrogenase,and ATPase were all significantly lower in winter compared to summer.In conclusion,our results support the hypothesis and demonstrate the importance of RPP as a regulatory mechanism when animals transition into a hypometabolic state.

Neuroprotective effects of acteoside in a glaucoma mouse model by targeting Serta domain-containing protein 4

AIM:To explore the therapeutic effect and main molecular mechanisms of acteoside in a glaucoma model in DBA/2J mice.METHODS:Proteomics was used to compare the differentially expressed proteins of C57 and DBA/2J mice.After acteoside administration in DBA/2J mice,anterior segment observation,intraocular pressure(IOP)monitoring,electrophysiology examination,and hematoxylin and eosin staining were used to analyze any potential effects.Immunohistochemistry(IHC)assays were used to verify the proteomics results.Furthermore,retinal ganglion cell 5(RGC5)cell proliferation was assessed with cell counting kit-8(CCK-8)assays.Serta domain-containing protein 4(Sertad4)mRNA and protein expression levels were measured by qRT-PCR and Western blot analysis,respectively.RESULTS:Proteomics analysis suggested that Sertad4 was the most significantly differentially expressed protein.Compared with the saline group,the acteoside treatment group showed decreased IOP,improved N1-P1 wave amplitudes,thicker retina,and larger numbers of cells in the ganglion cell layer(GCL).The IHC results showed that Sertad4 expression levels in DBA/2J mice treated with acteoside were significantly lower than in the saline group.Acteoside treatment could improve RGC5 cell survival and reduce the Sertad4 mRNA and protein expression levels after glutamate injury.CONCLUSION:Sertad4 is differentially expressed in DBA/2J mice.Acteoside can protect RGCs from damage,possibly through the downregulation of Sertad4,and has a potential use in glaucoma treatment.