组织因子途径抑制物2在胰腺癌中的表达及其对胰腺癌细胞迁徙及浸润转移过程中的作用机制研究

  • 格式:pdf
  • 大小:3.00 MB
  • 文档页数:84

华中科技大学同济医学院2001级博士学位论文

组织因子途径抑制物2在胰腺癌中的表达及其对胰腺癌细胞迁徙和浸润转移过程中的作用机制研究华中科技大学同济医学院附属协和医院普外科博士研究生俞建雄导师

王春友

中文摘要研究背景与目的:胰腺癌是恶性程度最高的肿瘤之一。由于其位置隐蔽,邻近器官多,症状不典型,现有的检查很难早期发现肿瘤,使多数患者在就诊时已是中晚期,手术切除率低(仅为15~30%),生存期短(5年生存率在5%左右)。而且,胰腺癌对现有的放、化疗治疗又极为不敏感。由此可见:常规治疗方法对胰腺癌的治疗效果很不理想。积极探索新的治疗方法,抑制胰腺癌的侵袭性,改善胰腺癌的预后已成为当务之急。组织因子抑制物2(Tissuefactorpathwayinhibitor2.TFPI.2),即先前报道的胎盘蛋白5(PPS),是一种广谱的丝氨酸蛋白酶抑制物,体外能强烈抑制包括纤溶酶、胰蛋白酶、删P一1和I协/IP一3在内等多种蛋白酶,在维持细胞外基质结构完整性以及调控肿瘤细胞侵袭浸润方面起着重要作用。TFPI.2基因分布广泛,在人类肝脏、肾脏、胰腺、骨骼肌等正常组织中都有着丰富表达。我们分析在TFPI-2在人类胰腺癌中表达情况,并转染TFPI一2于人类胰腺癌细胞Panc一1,探讨TFPI-2与Panc-1细胞迁徙和浸润转移能力之间的关系.为临床判断胰腺癌预后及后期的基因治疗奠定基础。方法:用RT—PCR、Westernblot方法检测正常胰腺组织、新鲜胰腺癌组织和癌旁组织中TFPI一2的表达水平,比较TFPI-2表达水平与胰腺癌恶性程度之间的关系:脂质体介导真核表达载体pBos—Cite-neo/TFPl一2转染人类胰腺癌细胞系Panc一1.比较TFPI一2表达组与TFPI-2非表达组在生长曲线、细胞迁徙和浸润能力、细胞凋亡率以及裸小鼠成瘤能力方面的差异性。结果:在正常胰腺组织中存在有TFPI-2的高表达,随着胰腺癌恶性程度的加深,TFPI一2表达水平呈进行性下降,两者之间存在显著的负相关性;脂质体可成功华中科技大学同济医学院2001级博士学位论文

介导真核表达载体pBos—Cite—neo/TFPI一2的稳定转染于Panc-1细胞,并使后者获得TFPI一2的稳定表达:TFPI-2表达组细胞在生长曲线、细胞迁徙能力及细胞凋亡率方面与TFPI一2非表达组之间无明显差异,但在细胞浸润能力、裸小鼠成瘤能力上均显著低于后者。结论:TFPI.2表达水平与胰腺癌恶性程度之间存在着显著的负相关性,可能成为胰腺癌预后的判断指标之一,并为基因治疗胰腺癌提供新的方向;脂质体可成功介导真核表达载体pBos—Cite—neo/TFP%一2的稳定转染于Panc一1,并使后者获得TFPI一2的稳定表达:TFPI-2虽不影响胰腺癌细胞的生长、迁徙能力及细胞凋亡率,但可显著降低胰腺癌细胞浸润能力、裸小鼠成瘤能力。为进一步开展肿瘤基因治疗提供实验依据。关键词:胰腺癌:组织因子抑制物2;预后;生长曲线;迁徙:浸润;基因治疗;成瘤能力;细胞凋亡;

2华中科技大学同济医学院2001级博士学位论文

Theexpressionoftissuefactorpathwayinhibitor2(TFPI一2)

inpancreaticcancer

andit’Sroleinmigrationandinvasion

ofpancreaticcancercelllinePane-1

Generalsurgerydepartment,Unionhospital,Tongjimedicalcollege,RUST

DoctorCandidate:YuJianxiong

Tutor:ProfessorWangChunyou

AbstractBackground&Objectives:PancreaticCancerremainsoneofthemost

challenging

malignanttumoringeneralsurgery.CurrentScreenmodalitiesarcunableto

identify

it

forinaccessiblelocation,proximitytoothervitalorgans,inherentlyaggressivepattern

ofgrowth,andatypicalsymptom,whichmakemostpatients

havelocal

or

metastasis

spreadatthetimeofpresentationthatprecludessurgicalresection.Lessthan30%ofcasesareconstitutecandidatesforresectionandtheoverall5-yearsurvivalrateislessthan5%.Furthermore,pancreaticcancerishi曲lyresistantto

current

available

chemotherapyandradiationprotocols.Therefore,newmodalitiesinthetreatmentofthisdiseasetoimproveit’Sprognosisarerequiredurgently.Humantissuefactorpathwayinhibitor-2(TFPI・2),alsocalledplacentalprotein5(PP5),isanewly

serine

proteaseinhibitorthatinhibitsplasmin,trypsin,metrixmetaUoproteinase

1and3in

vitro,whichisimportanttomaintaintheintegrityofextracellularmatrixandregulate

themigrationandinvasionoftumor.TFPI-2transcriptsal'eabundantinvariousadulthumantissues,suchasliver,kidney,pancreas,andskeletalmuscle.Weattemptto

establishthecorrelationbetweentheexpressionlevelofTFPI-2andtheprogression

ofpancreaticcancerafterdetectingtheexpressionlevelofTFPI一2inpancreatic

cancer,andtoidentify

theroleofTFPI一2inpancreatic

cancercellPane一1’S

migration

andinvasionaftertransffedngTFPI-2intoPane-1,basing

forclinical

prognosis

and

subsequentgenetherapy.Methods:ExpressionlevelofTFPI-2innormalandcancerousorjuxta-cancerous

pancreaswastestified

withWesternBlotandRT-PCR

respectively;thecorrelation

1华中科技大学同济医学院2001级博士学位论文betweentheexpressionlevelofTFPI一2andprogressionofpancreaticcancerwas

testedwitllSpearman’Srho.HumanTFPI-2expressionvector

pBos-Cite-neo/TFPI一2

wastransfferedintohumanpancreaticcancer

cellslinePane-1

with

Iipofectamine2000.Growthcurve,thenumberofcellspassingthrough

membraneof

Boydenchamberandtheabilityoftumorigenesisinnudemiceofpancreatic

cancer

celleitherTFPI一2expressingornotwere

determinedandcomparedbyANOVA.

Besides,theratioofcellapoptosiswasalsodetectedwithflowcytometry

and

compared.Results:Theexpression

levelofTFPI-2is

highest

in

normalpancreas,andis

decreasingalongwiththeprogressionofpancreaticcaneer,with

asignificantly

negativecorrelationbetweenexpressionlevelofTFPI-2

and

themalignancy-Human

TFPI.2expressionvector

pBos—Cite・neo/TFPI・2can

betransfferedinto

human

pancreaticcancercelllinePane.1withlipofectamine2000

successfully:TFPI-2

mRNAandproteincanbe

expressed

in

stablytransfectedgroup・There

isno

differencebetweentheTFPI・2expressinggroupandnon-TFPI-2expressinggrouponcellgrowthcurve,migration

andcell

apoptosis,but

ininvasion

assay,the

numberof

TFPI.2-expressingcellstoUaverse

aMatrigel-eoated

membranewas

obviously

decreasedcompared

withthatof

nonexpressingcells;Thesizegrown

innudemiceis

significantlysmallerthanits

counterpartat

3weeks・

Conclusions:Thereissignificantlynegativecorrelationbetweentheexpressionlevel

ofTFPI.2andtheprogressionofpancreafic

cancer,indicatingTFPI_2wouldbeanew

candidateforgenetherapyforpancreaticcancer.pBos—Cite-neo/TFPI-2canbetranfferedintohumanpancreaticcancercelllinePane-1with