Expressions of vascular endothelial growth factor in cirrhotic tissues and their relations to proto-oncogene c-fos, c-myc

Objective: To investigate the significance of vascular endothelial growth factor (VEGF) in the pathogene- sis of liver cirrhosis and the correlation between VEGF and proto-oncogene c-fos and c-myc in cir- rhotic liver. Methods: The proteins of VEGF, c-fos, and c-myc were identified immunohistochemically in each tissue section of 53 cases of liver cirrhosis. The correlations between VEGF, c-fos and c-myc were analyzed. The levels of VEGF protein in different Child gradings were also compared. Results: The proteins of VEGF were more highly ex- pressed in Child A and B patients than in Child C patients and controls. The expressions of both c-fos and c-myc were not statistically significant between VEGF positive and negative patients. Conclusions: The protein level of VEGF can reflect the compensation status of cirrhosis patients and may act as an anti-cirrhotic factor. The proto-oncogene c- fos, c-myc and VEGF may have different mecha- nisms in the course of cirrhosis or hepatic tumorigen- esis.

Promoter hypermethylation of tissue specific tumor supressor genes and point mutation in K-ras, c-myc proto-oncogenes in urinary (transitional cell) bladder carcinoma

In a total of 83 UN specimens were investigated for proto-oncogene mutations, tumor supressor genes promoter methylation status and c-myc and Ki-67 expression. Point mutations in c-myc were detected in cases with high grade and proliferation index. Mutated K-ras proto-onco- gene profiles were detected in 17 (21%) tumoral spiecemens that examined. Tumor specimens were also showed hypermethylated promoter domain for the SFRP2, MGMT tumor supressor genes. These findings showed the combine effect of mutated c-myc and K-ras oncogene and epigenetic inactivation of tissue specific tumor supressor genes (TS) play a crucial role in tumor progression and recurrence in UN carcinogenesis.

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。

Effects of Cadmium on Hepatocellular DNA Damage,Proto-Oncogene Expression and Apoptosis in Rats

Objective To study the effects of cadmium on hepatocellular DNA damage, expression of proto-oncogenes c-myc, c-fos, and c-jun as well as apoptosis in rats. Methods Cadmium chloride at the doses of 5, 10, and 20 μmol/kg was given to rats by i.p. and there were 5 male SD rats in each group. Hepatocellular DNA damage was measured by single cell gel electrophoresis （or comet assay）, while expression of proto-oncogenes c-myc, c-fos, and c-jun in rat hepatocytes were measured by Northern dot hybridization. C-Myc, c-Fos, and c-Jun were detected with immuno-histochemical method. Hepatocellular apoptosis was determined by TUNEL （TdT-mediated dUTP Nick End Labelling） and flow cytometry. Results At the doses of 5, 10, and 20 μmol/kg, cadmium chloride induced DNA damage in rat hepatocytes and the rates of comet cells were 50.20%, 88.40%, and 93.80%, respectively. Results also showed an obvious dose-response relationship between the rates of comet cells and the dose of cadmium chloride （r=0.9172, P〈0.01）. Cadmium chloride at the doses of 5, 10, and 20 μmol/kg induced expression of proto-oncogenes c-myc, c-fos, and c-jun. The positive brown-yellow signal for c-myc, c-fos, and c-jun was mainly located in the cytoplasm of hepatocytes with immunohistochemical method. TUNEL-positive cells were detected in cadmium-treated rat livers. Apoptotic rates （%） of cadmium-treated liver cells at the doses of 5, 10, and 20 μmol/kg were （17.24 ±2.98）, （20.58± 1.35）, and （24.06±1.77） respectively, being significantly higher than those in the control. The results also displayed an obvious dose-response relationship between apoptotic rates and the dose of cadmium chloride （r=0.8619, P〈0.05）. Conclusion Cadmium at 5-20 μmol/kg can induce hepatocellular DNA damage, expression of proto-oncogenes c-myc, c-fos, and c-jun as well as apoptosis in rats.

Current concepts in ameloblastoma-targeted therapies in B-raf proto-oncogene serine/threonine kinase V600E mutation: Systematic review

BACKGROUND Ameloblastomas are common benign epithelial odontogenic neoplasms that present an aggressive and unpredictable behavior that may modify treatment strategies.Different signaling pathways that participate in the progression of these tumors have been identified.B-raf proto-oncogene serine/threonine kinase(BRAF)is a protein involved in the behavior of ameloblastomas,and it is related to many cell mechanisms.BRAF gene mutations have been identified in ameloblastomas,of which the BRAF V600E(valine substituted by glutamic acid at amino acid 600)mutation has been the most common and can be present concomitantly with other mutations that may be involved in its behavior.Targeted therapies have been used as an alternative in the case of resistance or contraindications to conventional treatments.AIM To document the presence of BRAF V600E and additional mutations,their behavior,and targeted therapies in these tumors.METHODS An electronic literature search was conducted according to PRISMA guidelines in PubMed/MEDLINE,Cochrane,EMBASE,and SpringerLink using the terms“ameloblastomas”,“BRAF V600E”,“additional mutations”,and“targeted therapies”.Ameloblastomas were classified according to WHO guidelines.Inclusion criteria were articles in English,published not more than 10 years ago,and studies with laboratory works related to BRAF V600E.Articles were evaluated by two independent reviewers and retrieved for full-text evaluation.The EBLIP Critical Appraisal Checklist was used to evaluate the quality of the eligible studies.Descriptive statistical analysis was performed.RESULTS Two independent reviewers,with a substantial concordance indicated by a kappa coefficient of k=0.76,evaluated a total of 19 articles that were included in this study.The analysis registered 521 conventional ameloblastomas(AM),81 unicystic ameloblastomas(UA),13 ameloblastic carcinomas(AC),three metastatic ameloblastomas(MA),and six peripheral ameloblastomas(PA),of which the histopathological type,anatomic location,laboratory tests,expression of BRAF mutation,and additional mutations were registered.The BRAF V600E mutation was found in 297 AM(57%),63 UA(77.7%),3 AC(23%),1 MA(50%),and 5 PA(83.3%).Follicular type predominated with a total of 116 cases(40%),followed by plexiform type with 63 cases(22.1%).Furthermore,both types presented additional mutations,in which alterations in JAK3 P132T,SMARCB1,PIK3CA,CTNNB1,SMO,and BRAF G606E genes were found.Four case reports were found with targeted therapy to BRAF V600E.CONCLUSION The identification of BRAF V600E and additional mutations as an aid in targeted therapies has been a breakthrough in alternative treatments of ameloblastomas where surgical treatments are contraindicated.

Polymerase chain reaction-single strand conformational polymorphism analysis of rearranged during transfection proto-oncogene in Chinese familial hirschsprung's disease

AIM: To investigate the relationship between mutations of rearranged during transfection (RET) proto-oncogene and Chinese patients with Hirschsprung's disease (HD), and to elucidate the genetic mechanism of familial HD patient at the molecular level.METHODS: Genomic DNA was extracted from venous blood of probands and their relatives in two genealogies.Polymerase chain reaction (PCR) products, which were amplified using specific primers (RET, exons 11, 13, 15and 17), were electrophoresed to analyze the single-strand conformational polymorphism (SSCP) patterns. The positive amplified products were sequenced. Forty-eight sporadic HD patients and 30 normal children were screened for mutations of RET proto-oncogene simultaneously.RESULTS: Three cases with HD in one family were found to have a G heterozygous insertion at nucleotide 18 974 in exon 13 of RET cDNA (18 974insG), which resulted in a frameshift mutation. In another family, a heterozygosity for T to G transition at nucleotide 18 888 in the same exon which resulted in a synonymous mutation of Leu at codon 745 was detected in the proband and his father. Eight RET mutations were confirmed in 48 sporadic HD patients.CONCLUSION: Mutations of RET proto-oncogene may play an important role in the pathogenesis of Chinese patients with HD. Detection of mutated RET proto-oncogene carriers may be used for genetic counseling of potential risk for HD in the affected families.

Expressions of estrogen receptor subtypes and c-met proto-oncogene in endometrial carcinoma and their correlation

Objective To investigate the expressions of estrogen receptor(ER)subtypes and c-met proto-oncogene in human endometrial carcinomas and to assess the clinical significance of ER and c-met in this carcinoma.Methods Reverse transcription PCR(RT-PCR)was used to detect the expressions of ERα,ERβ and c-met proto-oncogene mRNA in 30 samples of endometrial carcinoma and 11 samples of normal endometrium.Results The expression of ERα in endometrial carcinoma(0.70±0.40)was significantly reduced in comparison to that in normal endometrium(1.14±0.56,P<0.05).A similar finding was made for the expression of ERβ in carcinoma(0.24±0.18)versus normal tissues(0.48±0.20,P<0.05).In contrast,c-met mRNA expression was increased in endometrial carcinoma(1.45±0.72)compared to that in normal endometrium(0.42±0.31,P<0.01).A decrease tendency of the expression of ERα was also found from Stage Ⅰ(0.82±0.41)to a more severe Stag Ⅱ-Ⅲ of endometrial carcinoma(0.42±0.17,P<0.05).The analysis of ERα and ERβ mRNA revealed a decrease tendency from shallow to deep invasion of the uterine muscles(P<0.05).We found that the expressions of ERα and ERβ were negatively correlated with c-met proto-oncogene with a coefficient correlation of-0.63(P<0.01)and-0.32(P<0.05),respectively.Conclusion ERα and ERβ are both involved in mutagenic action of carcinogen.C-met proto-oncogene plays an important role in the carcinogenesis and development of endometrial carcinoma.C-met and ER expressions show a negative correlation in the development of endometrial carcinoma.

华蟾素通过调控MYH9/USP7/c-MYC通路抑制急性髓系白血病细胞免疫逃逸

【目的】探讨华蟾素调控肌球蛋白重链9(MYH9)/泛素特异性蛋白酶7(USP7)/骨髓细胞瘤病毒癌基因(c-MYC)通路对急性髓系白血病(AML)细胞免疫逃逸的影响。【方法】(1)体内实验:建立裸鼠异种移植瘤模型,评估华蟾素对AML细胞在体内生长和免疫逃逸的影响。(2)体外实验:使用不同浓度的华蟾素处理人AML细胞株HL-60,细胞计数试剂盒8(CCK-8)法检测细胞活力,Transwell实验检测细胞侵袭能力。将HL-60细胞与活化的CD8^(+)T细胞共培养,流式细胞术检测CD8^(+)T细胞表面标志物CD25的表达,酶联免疫吸附分析(ELISA)检测共培养上清液中细胞因子[白细胞介素2(IL-2)和干扰素(IFN-γ)]的水平,CytoTox96非放射性细胞毒性分析评估CD8^(+)T细胞对HL-60细胞的毒性。Western Blot法检测MYH9、USP7和c-MYC的蛋白表达,免疫共沉淀(Co-IP)法检测MYH9、USP7和泛素化之间的相互作用。转染MYH9过表质粒,验证华蟾素在AML中的作用机制。【结果】华蟾素抑制裸鼠移植瘤生长,增强CD8^(+)T细胞抗肿瘤的能力。华蟾素浓度依赖性地抑制HL-60细胞活力、侵袭。华蟾素处理后上调CD8^(+)T细胞表面标志物CD25的表达,同时还上调IL-2和IFN-γ水平。华蟾素增强CD8^(+)T细胞对HL-60细胞的毒性。华蟾素抑制HL-60细胞MYH9、USP7和c-MYC的蛋白表达,MYH9通过募集USP7促进c-MYC去泛素化,华蟾素抑制MYH9介导的c-MYC去泛素化。【结论】华蟾素可通过抑制MYH9的表达进而减少去泛素化酶USP7对c-MYC的募集,促进c-MYC泛素化降解,从而抑制AML细胞免疫逃逸。

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。

Mutation of RET proto-oncogene in Hirschsprung's disease and intestinal neuronal dysplasia

AIM： To investigate the genetic relationship between Hirschsprung＇s disease （HD） and intestinal neuronal dysplasia （IND） in Chinese population.METHODS： Peripheral blood samples were obtained from 30 HD patients, 20 IND patients, 18 HD/IND combined patients and 20 normal individuals as control. Genomic DNA was extracted according to standard procedure. Exons 11,13,15,i7 of RET proto-oncogene were amplified by polymerase chain reaction （PCR）. The mutations of RET proto-oncogene were analyzed by single strand conformational polymorphism （SSCP） and sequencing of the positive amplified products was performed.RESULTS： Eight germline sequence variants were detected. In HD patients, 2 missense mutations in exon 11 at nucleotide 15165 G→A （G667S）, 2 frameshifc mutations in exon 13 at nucleotide 18974 （18974insG）, 1 missense mutation in exon 13 at nucleotide 18919 A→G （K756E） and 1 silent mutation in exon 15 at nucleotide 20692 G→A（Q916Q） were detected. In HD/IND combined patients, 1 missense mutation in exon 11 at nucleotide 15165 G→A and 1 silent mutation in exon 13 at nucleotide 18888 T→G （L745L） were detected. No mutation was found in IND patients and controls.CONCLUSION： Mutation of RET proto-oncogene is involved in the etiopathogenesis of HD. The frequency of REr proto-oncogene mutation is quite different between IND and HD in Chinese population, IND is a distinct clinical entity genetically different from HD.

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。

THE PRELIMINARY APPLICATION OF IN SITU HYBRIDI-ZATION IN DETECTING PROTO-ONCOGENES EXPRESSION IN HUMAN LEUKEMIC CELLS

An in situ hybridization technique with 35S labelled proto-oncogene probes (c-myc & c-fes) was used to detect their expression in bone marrow cells of 22 cases of leukemia of various types and immature granulocytes and erythroblasts of 16 nomal myelograms as controls. Both c-myc and c-fes were detectable in leukemic cells as well as in immature granulocytes and erythroblasts of normal bone marrow, but the expression extent varied in different cases. The levels of c-myc expression in leukemic cells were higher than those in controls (P<0.001). There was no difference of c-fes expression in two groups of bone marrow cells (P>0.05). This technique provides us a new method in studying variations of proto-oncogene expression in leukemic cells.

Malignant pheochromocytoma in neurofibromatosis; mutation screening of RET proto-oncogene, VHL and SDH gene

AIM: To investigate pathogenic mutations related to malignant pheochromocytoma in neurofibromatosis(NF).METHODS: We present a patient with NF and metastatic pheochromocytoma in whom genetic screening for presence of pathogenic mutations in RET protooncogene, von Hippel-Lindau(VHL) and succinate dehydrogenase complex subunits B(SDHB) genes were investigated. RET proto-oncogene mutation screening for exons 10, 11, 13, 14, 15, 16 were examined by polymerase chain reaction(PCR) and direct DNA sequencing in patient. Mutation screening for exons 1, 2, 3 of VHL gene was carried out. Both forward and reverse strandswere subjected to direct sequencing after PCR amplification. The entire coding sequence of SDHB gene was screened for the presence of pathogenic mutations by PCR-sequencing.RESULTS: A 45-year-old man presented with abdominal pain and hypertension over the previous year. The patient was a known case of neurofibromatosis type 1(NF1) who presented at the age of 15 years with hyperpigmented and hypopigmented lesions. After complete evaluation for hypertension, biochemical tests and imagings indicated a malignant pheochromocytoma of 120 mm × 70 mm in size. The patient underwent left adrenalectomy, nephrectomy and splenectomy. After surgery the symptoms improved and blood pressure was controlled. After 5 years he was admitted again for evaluation of hypertensive crisis. Biochemical tests were again consistent with pheochromocytoma and disease relapse. Imaging studies and liver biopsy confirmed metastatic pheochromocytoma to the liver and para-aortic area. 131 Iodine-metaiodobenzylguanidine therapy was carried out. Genetic screening of VHL(exons 1, 2, 3), RET proto-oncogene(exons 10, 11, 13, 14, 15, 16) and SDH complex subunits revealed no pathogenic mutation. CONCLUSION: We conclude that mutations in the NF1 gene are responsible for the patient's clinical findings. However, would be helpful to further examine somatic mutations for a more precise study of genotypephenotype correlation.

A NOVEL Ser73Gly VARIATION OF SUCCINATE DEHYDROGENASE,SUBUNIT D AND A Cys634Gly MUTATION IN Ret PROTO-ONCOGENE OBSERVED IN A CHINESE MULTIPLE ENDOCRINE NEOPLASIA TYPE 2A PATIENT

Multiple endocrine neoplasia type 2A （ MEN2A ） is an autosomal dominant cancer syndrome that is characterized by medullary thyroid carcinoma （MTC）, pheochromaocytoma （50% - 60% of cases ）, and hyperplasia of the parathyroid glands （ 20% - 30% of cases ）. MEN-2A comprises a heterogeneous group of neoplastic disorders that most commonly have a single missense substitution of the Ret proto-oncogene （RET） involving exons 10 and 11. Here, we reported a novel case of MEN2A associated with two variations in two distinct genes, Cys634Gly in RET and a rare Ser73Gly substitution in succinate dehydrogenase, subunit D （SDHD）. Because the patient presented with medullary thyroid carcinoma and pheochromocytoma but without parathyroid gland involvement, we speculated that this clinical feature could be correlated with the two substitutions. This is the first report of a MEN2A case involving two different changes one in the RET gene and the other in the SDHD gene.

c-Myc通过lnc-TBL1XR1-5影响口腔鳞状细胞癌的发生发展

目的研究c-Myc调节的长链非编码RNA TBL1XR1-5(lnc-TBL1XR1-5)对口腔鳞状细胞癌(OSCC)进展的影响。方法根据c-Myc的表达对TCGA数据库中头颈部鳞状细胞癌(HNSCC)样本进行生物信息学分析,筛选出c-Myc表达密切相关的lnc-TBL1XR1-5。实时定量聚合酶链式反应(qRT-PCR)检测c-Myc和lnc-TBL1XR1-5在OSCC癌组织和癌旁组织中的表达关系,分析其在HOK、HN6、CAL27细胞系中表达差异,c-Myc过表达和敲低对lnc-TBL1XR1-5的影响。双荧光素酶报告基因测定用于验证c-Myc与lnc-TBL1XR1-5启动子区的结合。RNA荧光原位杂交(RNA FISH)用于确定lnc-TBL1XR1-5在OSCC细胞系中的定位。通过qRT-PCR、细胞计数、CCK-8、集落形成等实验观察lnc-TBL1XR1-5的过表达或敲低对OSCC细胞增殖的影响,并通过划痕实验、Transwell实验等观察lnc-TBL1XR1-5的过表达或敲低对OSCC细胞迁移的影响,最后通过观察培养基颜色和pH变化观察lnc-TBL1XR1-5的过表达或敲低对OSCC细胞代谢的影响。结果c-Myc对lnc-TBL1XR1-5在OSCC细胞系和组织中的表达具有正调控作用。通过双荧光素酶报告基因测定验证了c-Myc与lnc-TBL1XR1-5启动子区的结合。RNA FISH显示lnc-TBL1XR1-5定位于OSCC细胞的细胞核。lnc-TBL1XR1-5的过表达促进了OSCC细胞系的迁移、代谢和增殖,而敲低则具有相反的作用。结论c-Myc在OSCC中正向调节lnc-TBL1XR1-5,lnc-TBL1XR1-5促进OSCC的迁移、增殖和代谢。

Effect of cisplatin-based concurrent radiochemotherapy on malignant degree of advanced cervical cancer and expression of proto-oncogene and tumor suppressor genes

Objective:To study the effect of cisplatin-based concurrent radiochemotherapy on the malignant degree of advanced cervical cancer and the expression of proto-oncogene and tumor suppressor genes.Methods: A total of 82 patients with advanced cervical cancer who were treated in our hospital between July 2013 and December 2016 were collected and divided into control group and observation group according to random number table, with 41 cases in each group. The control group of patients received radiotherapy alone, while the observation group of patients received cisplatin-based concurrent radiochemotherapy. Tumor marker levels in serum as well as proto-oncogene and tumor suppressor gene expression in tumor tissue were compared between two groups of patients before and after treatment.Results:Before treatment, differences in tumor marker levels in serum as well as proto-oncogene and tumor suppressor gene expression in tumor tissue were not statistically significant between two groups of patients. After treatment, serum tumor markers SCC, CA50, CA724 and CEA levels of observation group were significantly lower than those of control group;proto-oncogene DEK, c-myc and PIK3CA mRNA expression in tumor tissue were significantly lower than those of control group;tumor suppressor genes p53, SOCS-1, FHIT and PTEN mRNA expression in tumor tissue were significantly higher than those of control group.Conclusions:Cisplatin-based concurrent radiochemotherapy can effectively reduce the tumor malignancy and balance the proto-oncogene / tumor suppressor gene expression in patients with advanced cervical cancer.

基于细胞系和类器官研究c-Myc在肝癌治疗和耐药中的作用

目的:基于肝癌细胞系与类器官的药物基因组学数据探讨骨髓细胞瘤癌基因(c-Myc)的潜在治疗效果。方法:收集肝癌细胞系的药敏、功能基因组和基因表达数据,评估c-Myc的表达与药敏的关联。统计c-Myc表达在肝癌测序队列中的差异和预后相关性。免疫组织化学染色验证c-Myc在肝癌患者的表达,检测其与类器官生物库类器官的药敏关联。选取三种不同的c-Myc抑制剂在肝癌细胞系和类器官上进行药物筛选,检测干预c-Myc对二维、三维水平的肿瘤杀伤作用。生物信息学分析探究c-Myc与靶向耐药的相关性。结果:生物信息学分析联合免疫组织化学鉴定c-Myc在肝癌中调控药敏的潜在作用。c-Myc在癌组织中的表达明显高于癌旁组织,而且c-Myc的表达在靶向药耐药患者中高于靶向药敏感患者(P<0.05)。药敏实验揭示了c-Myc抑制剂THZ1、ABBV-744、JQ1可杀伤肿瘤细胞及类器官,并且与仑伐替尼在细胞系SNU-739中显示出显著的协同致死作用(协同系数均>1)。进一步的类器官生物库数据分析显示,c-Myc与干性介导的靶向耐药显著正相关(R=0.87)。结论:c-Myc在在靶向治疗耐药患者中高表达,并且抑制c-Myc可在二维、三维体外模型中起到很好的肿瘤杀伤效果,肝癌中可作为一个新的靶点。