688 泰山医学.院学报 JOURNAL OF TAISHAN MEDICAL COLLEGE Vo134 Nn 9 2013 C。_。myc expression is not related with pathological progression of gastric cancerl WANG Ke—qiang ZHU Bei HAN Guo-xin LIU Zhen—hong DONGYE Shen一 L/Yan (1.Central Laboratory of the Affiliated Hospital ofTaishan Medical College,Taian 271000,China; 2・Institute of Oneology,Medical College of Wuhan University&Department of Oncolgye。 Zhongnan Hospital of Wuhan University,Wuhan 430071,China) Abstract:Objective:Oncogene c—myc plays an important role in many tumors.This study was conducted to investi. gate the relationship of c—myc oncogene expression with major pathological characteristics of gastirc cancer(GC).Meth. ods Ei ghty—one GC specimens were studied for c—myc oncogene ampliifcation using non—radioactive in situ hybridization method.The c—myc overexpression status was con'elated with tumor differentiation。tumor invasion and lymph node metas. tasis.Results Among the 81 pathology confirmed GC patients,55(67.9%)were ound tfo have c—myc overexpression in cancer tissues.The rates f oe—myc overexpression were 72.7%(24/33)in intestinal type GC and 64.6%(31/48)in difuse tpey GC(P>0.05);74.3%(36/35)in well diferentiated tumor nd 63.O%(29/46)ian poody diferentiated tumor(P>0.05);81.8%(9/11)in tumors limited to superficila muscles and 65.7%(46/70)in tumors invading into deep muscle and beyond(P>0.05);and 66.7%(38/57)in tumors with lymph node metstasesa and 70.8%(17/24) in tumors itwhout lymph node metastases(P>0.05).Conclusions c—myc oncogene overexpression may be arI indepond- ent proliferation indicator for GC,and c—myc amplification is a common finding in advanced—stage GC. Key words:Gastric cancer;c—myc gene;in situ hybridization;clinical pathology C—myc基因表达与胃癌病理进展无关 王克强 朱蓓‘ 韩国新‘ 刘振中 东野圣伊 李雁 430071) (1.泰山医学院附属医院,山东泰安271000; 2.武汉大学医学院肿瘤研究所,武汉大学中南医院肿瘤科,湖北武汉摘要:目的 癌基因c—myc在许多肿瘤中都起重要作用。本课题研究胃癌组织中e—myc癌基因表达与胃癌 主要病理特征的关系。方法应用非放射性原位杂交技术检测8l例胃癌标本中c—myc基因的扩增情况,分析其 与肿瘤分化、肿瘤浸润和淋巴结转移的关系。结果—在81例胃癌标本中,c—myc基因扩增者有55例(67.9%)。c myc基因扩增率在肠型胃癌是72.7%(24/33),弥漫型胃癌是64.6%(31/48)(P>0.05);在高分化肿瘤中占 74.3%(36/35),低分化肿瘤中占63.O%(29/46)(P>0.05);在肿瘤浸润浅肌层者占81.8%(9/11),浸润深肌 层者占65.7%(46/70)(P>0.05);有淋巴结转移者占66.7%(38/57),无淋巴结转移者占70.8%(17/24)(P> 0.05)。结论c—myc基因扩增可能是表示胃癌增生程度的指标,是晚期胃癌中常见的癌基因改变。 关键词:胃癌;c—myc基因;原位杂交;临床病理 中图分类号:R446.8文献标识码:A文章编号:1004-7115(2013)09-0688-04 doi:10.3969/j.issn.1004—7l15.2013.09.015 The c—myc gene,mapped on human chromo— some 8q24,encodes the transcription factor c—myc affects cell cycle regulation,apoptosis and metabolism, and negatively affects cellular diferentiation and cell adhesion.Ectopic expression of the c—myc oncopro- tein prevents cell cycle arrest in response to growth・。 protein,which heterodimerizes with a partner protein, Max,to regulate gene expression.c—myc positively Biography:Wang Ke—qing(1962一),man,bom ian Xintai Shandong,Associate professor,mostly engage in morphology Corresponding author:LI Yah. 泰山医学院 学报 689 JOURNAL OF TAISHAN MEDICAL COLLEGE Vo1.34 N饥9 2013 inhibitory signals, leading to uncontrolled cell prolifer- ation.Moreover,c—myc activation in quiescent cells Road.National Hi—Tech Industry Development Zone. Luoyang,Henan Province,China).The probe COn— centration was 15 7 g/ml and sensitivity was 0.1 pg DNA.After treatment with 0.1N He1,RNase A,pro— tease K and 0.1%Glycin,the slides were pre—hy— is sufficient to induce cell cycle entry in the absence of growth factors.[ 】Deregulated c——myc expression and signal pathway contibutre to he neoplasttic phenotype of deregulated growth,anchorage—independent growth, and glycolytic metabolism.c—myc overexpression is observed in many different malignancies such as breast cancer,ovarian cancer,gastric cancer,lung cancer, bridized f0r l h at room temperature in pre—hybridiza— tion solution(4×SSC,50%formamide,1×Denhardt solution.0.5%PEG and 0.5 mg/ml ssDNA).After washing the hybridization solution(probe concentration colorectal cance and other cancers[ ~9。In tllis pa- . O.27 g/m1)was added,the slides were sealed with per,we studied c—myc expression profile in GC tis. sues using in situ hybridization,and explored the sig— nificance of this gene in GC pathological progression. 1 Materials and Methods 1.1 Clinical specimens Ei ght—one pathology—con— ifrmed gastirc carcinoma specimens were collected from Jan 2012 to Jun 2013 from the Afifliated Hospital of Taishan Medical College and the Institute of Oncology, Medical College of Wuhan University.There were 53 males and 28 females aged between 37 to 65 years old (mean age 58.6 years).Among these specimens were 35 cases with carcinomas at gas ̄ic cardia,17 cases at gastirc body and 29 cases at antrum.According to Lauren classiifcation.there were 33 cases with intesti. nal type carcinoma and 48 cases with diffused type car. cinoma.Thiay—five cases were with well—differentia. ted carcinoma and 46 were poorly differentiated.In 11 cases cancer invaded superficial muscle layer and in hte rest cancer invaded beyond deep muscle.Fifty— seven of these cases had lymph node metastases and 24 had no lymph node metastases.After surgl’c、al remova1. hte specimens were snap—-frozen in liquid nitrogen and eryo—sectioned at一260C.with thickness between 6 to 10 7 m,which were mounted on aminopropyltrie。 thoxysilane(APES,Sigma,St Louis,Ohio,USA) treated slides. 1.2 In situ hybridization H—C—myc probe was pur- chased from Sina~American Biotechnology Companv (No.007,Sanshan Road。National Hi—Tech Indu8一 try Development Zone,Luoyang,Henan Province, China),with the length of 1.4 kb(Exon 3).Non— radioactive digoxigenin—l 1一UTP labeling was per. formed using random priming method,with reagent kit from Boehringer mannheims(purchased from Sino—A. merican Biotechnology Company,No.007,Sanshan cover glass and treated in formamide chamber at 95℃ for 1O一15 min.Then the slides were hybridized over— night at 42℃in a humid chamber.after which the cover glass was removed in 2×SSC solution,and alka— line phosphatase labeled anti—DIG antibody(1:500 dilution)was added and incubated for 2 h.After wash. ing.5一bromo一4一chloro一3一indoxyl phosphate di— sodium(BCIP)/nitroblu—tetrazolium(NBT)color development substrate was added and kept in the dark ofr color reaction,which was terminated by TE buffer washing when color reaction was sumcient.The slides were counter—stained with eosin.and sealed.Normal gastric tissues from the same specimens were treated in the same fashion as negative controls,and positive control slides were provided by the probe supplier. 1.3 Slides interpretation When the slides were viewed under microscope(400 x),dark brown—blue granules and particles could be found in positively stained cells,and the background was stained red bv eosin.Positive and negative stained specimens were re.. corded respectively.Data on conventional pathology of the specimens were collected from routine pathological report based on gross pathology and hematoxylin and e. osin(HE)stained tissue slides. 1.4 Statistical analysisComparisons between c myc positive rates in diferent pathological subgroups were analyzed using Chi—square test.with P<0.05 as sta— tistica1 significance. 2 RESUI 2.1 c—myc expression in GC tissues Of the 81 GC specimens,55(67.9%)were found to have c—myc overexpression,which showed dark~brown granules in cancer tissue.The relationship of c—myc overexpres。 sion and the pathologic characteristics of tumors were summarized in Table 1 NS:not signiifcant’Chi—square test 2.2 Correlation between c—myc overexpression and not reached statistically signiifcance( =0.135,P> major pathological characteristics Three major pathologi. 0.05)(Fig 1). cal parameters,tumor diferentiation,depth of tissue c my ̄o、 e oI】≈畦 p|0 e}5冲“ invasion and lymph node metastasis——were particularly 9。 analyzed in this study to explore heitr correlation with c Se —myc expression. 0 60 2.2.1 In terms of tumor differentiation There were 35 (43.2%,35/81)cases with well differentiated tumors and 46(56.8%.46/81)poorly differentiated tumors. Among the 55 c—myc positive cases.26 were well dif- 霉 壶 §_0 至 ferentiated tumor,accounting for 74.3%(26/35)the well differentiated group,and 29 were poorly differenti— :0 1e ated,accounting for 63.0%(29/46)of he poorlty dif- 0 球}m ^u ̄;xtsion∞idi 1 l node‘I艟s i ferentiated group( =1.153,P>0.05)(Fig 1). 2.2.2 In terms of tumor invasion There were l1 cases gIIre 1 Relationship between c—myc overexpression and (13.6%,1 1/81)with tumors invasion limited to the superifcial muscle layer and 70 cases(86.4%,70/ pathological characteristics in gastric cancer.Well=well difer- entiated,poor poody differentiated;S=tumor invading su— 8 1)with tumors invading beyond the deep muscle lay— er.In cases wih stuperficial muscle layer invasion,c— perficial muscle layer,D=tumor invading deep muscle layer; LN一=lymph node metstasis negative.LN+=laymph node metastasis positive.The percentage of c—myc overexpression myc overexpression was found in 9 cases,accounting for 81.8%(9/11)of the group.In cases with deep muscle invasion,c—myc overexpression was observed WaS not statistically significant between poorly diferentiated tumors(63.0%)and well diferentiated turaors(74.3%)(P> in 46 cases,accounting f0r 65.7%(46/70)of the group.The difference in c—myc expression between 0.05),between tumors invading deep muscle(65.7%)than those invading superficial muscle(81.8%)(P>0.05),and between tumors with lymph node metastases(66.7%)and those hese ttwo groups were statistically very signiifcant( without lymph node metastases(70.8%)(P>0.05)(Chi— square test). 3 DISCUSSION GC is one of the most common malignant tumors worldwide and continues to be a highly aggressive ma— 1.13,P>0.05)(Fig 1). 2.2.3 In terms of lymph node metastases There were 57 cases(70.4%,57/81)wiht lymph node metastases and 24 cases(29.6%,24/81)wihoutt lymph node metastases.Of the lymph node positive group,c—myc overexpression was found in 38 cases,which was 66. lignancy with poor prognosis and low long—-term Surviv・・ mainly on the stage of the disease.wi出early GC hay— ing a 5 year survival of 9O一100%and advanced rates.The survival of patients with GC depends 7%(38/57)of the group.In contrast,in the lymph alnode negative group,c—myc overexpression was found in 17 cases,accounting f0r 70.8%(17/24)of the group.The differences between these two groups did tumors a 5 year survival of15—25%.The role of other 泰山医学院 学报 691 MEDICAL COU EGE Vo1.34 No.9 2013 JOURNAL OF TA1SHAN prognostic factors in these tumors is still under mvestl— gation. Conventional pathology demonstrated that tie influence on the histological features.[12’ ]As c— myc may play an important role to predict more rapid certain types of GC usually showed much more aggres。 sive biological behavior than other types,and such pathological features include tumor differentiation, depth of tumor invasion and lymph node metastasis.【10j growth characteristics and fast tumor progression of gas— tric cancer,this molecule could be used as a valuable marker for GC proliferation. REFERENCES: With the development of molecular biology,it has been found that there are many genes involved in GC devel— opment and pathological progression,including the [1]Amati B,Alevizopoulos K,Vlach J.Myc and the cell cycle[J]. Front Biosci,1998,3:D250—268. plasminogen activator(uPA)and its inhibitor PAI一1 cancer,2000,7:143—164. [2]Hap DJ,Dickson RB.C—myc in breast cancer[j].Endocr relat (plasminogen activator inhibitor type 1),the cell—cy— cle regulator cyclin E,epidermal growth factor(EGF), cell proliferation related e—myc,the apoptosis inhibitor bcl一2.the cell adhesion molecule E—cadherin,and hte multifunctional protein beta—catenin.【 ¨The rela— tionship between these molecular markers and the con- ventional pathological parameters is currently under in・ tensive investigation,as elucidation of these molecular profiles may provide more information on biological be— havior of GC. Using highly sensitive in situ hybridization meth— od,we found 67.9%(55/81)of the gastric tumors had c—myc overexpression in the present work,which is similar to the results by Onoda et al,who found that 68.6%of primary gastric carcinoma had c—myc mR— NA overexpression.[121 c—myc expression is known to be continuously high in proliferating cells but not in most quiescent or terminally differentiated cells。[13. ] Although the incidence of cells with c—-myc DNA am・- plifieation is low(1ess than 12%)in carcinogenesis of hte stomach,Onoda et al reported that e—myc mRNA and c--myc protein were overexpressed in the early stage of stomach cancer:mRNA overexpression in 54. 8%of advanced cases and in 90.0%of early ca— ses. ‘ c—myc plays a central role in normal growth and development,as well as in cellular transformation and carcinogenesis in vitro.1 引Expression of c—myc protein correlated with proliferative activity of gastric cancer cells.However,we could not demonstrate a di— rect relationship between expression of c——myc mRNA nad progression or extent of diseases. Our results suggested that c— myc overexpression was very common in GC and such expression was not related to GC pathological progression.The percentage of c—-myc overexpression was not signiifcantly different between poorly diferentiated GC and well differentiated GC,between tumors invading beyond deep muscle and those limited to superifcial muscle.and between tumors wiht lymph node metastases than those wihtout lymph node metastases.These results are in line with previous findings suggesting that e—-myc overexpression had lit— [3]Sanz—Ortega J,Steinberg SM,Moor E,et a1.Comparative study of tumor angiogenesis and immunohistochemistry for p53,c— ErbB2.c—mye and EGFr as prognostic factors in gastric cancer [J].Histol Histopathol,2000,15:455—462. [4]Ishii HH,Gobe GC,Pan W,et a1.Apoptosis nad cell proliferation in the development of gastric carcinomas:associations with c—myc and p53 protein expression[J].J Gastrenterol Hepatol,2002,17: 966—972. [5]zajac—Kaye M.Myc oncogenc:a key component in cell cycle erg- ulation and.its implication for lung cancer[J].Lung Cancer, 200l,34(2):s43-46. [6]Xie D,Sham JS,Zeng W'F,et a1.Heterogeneous expression and association of beta—catenin,p16 and c—myc in multistage color- ectal tumorigenesis and progression detected by tissue microarray [J].Int J Cancer,2003,107:896—902. [7]Ij Fu—iun,Deng Hui,Wang Hong—wei,et 1a.Effects of external application of chinese mcdicine on diabetic ulcers and the expres— sion8 of B—catenin,c—myc and K6[J].Chin J Integr,2011:17 (4):261—266. [8]A lbihn A,Johnsen JI,Henriksson MA.MYC in oncogenesis and as a target ofr cancer therapies[J].Adv Cancer Res,2010,107: 163—224. [9]Skvotrsova I,Skvortsov S,Raju U,et 1a.Epithelial—to—mesen— chymal transition and c—myc edpression are the detemninants of cetuximab--induced enhancement of squamous cell carcinoma ra- dioresponse[J].Radiother Onoel,2010,96(1):108一l15. [1O]Kim l-O,Karpeh Ms.su『gjca1 approaches and outcomes in the treatment ofgastric cancer[J].Semin Radiat Oncol,2002,12: 162—169. [1 1]Holfer H,Becker KF.Moleculra mechanisms of carcinogenesis in gastric cancer【J].Recent Results Cancer Res,2003,162:65— 72. [12]Onoda N,Maeda K,ChungYS,eta1.Overexpression of c—myc messenger RNA in primary and metsatatic lesions of carcinoma of the stomach[J].J Am Call Surg 1996;182:55—59. [13]Hurlin PJ,Poley KP,Ayer DE,et 1a.Regulation of c—myo and Mad during epidermal diferentiation and HPV—associated tumor. genesis[J].Oncogene,1995,11:2487—2501. [14]Chin L,Schreiber—Agus N,Pellicer I,et 1a.Contrasting roles ofr Myc and Mad protein in cellulra growth and diferentiation[J]. Prec Natl Acad Sei USA,1995,92:8488—8492. [15]Lee LA,Dolde C,Barrett J,cta1.Alink between c—myc~me. diatcd transcriptional repression and neoplsatic transformation[J]. J Clin Invest,1996,97:1687—1695. [16]Kim YJ,Ghu HD,Kim DY,et a1.Expression of cellular onco. genes in human gastirc carcinoma:c—myc,c—erb B2。and C— Ha—ras[J].J surg Oncol,1993,54:167—170. (收稿日期2012—10—8)