醫(yī)院培訓課件：《信號轉(zhuǎn)導與腫瘤》

信號轉(zhuǎn)導與腫瘤

SignalTransductionandCancer細胞信號轉(zhuǎn)導————生命的表述語言細胞信號轉(zhuǎn)導研究是當前生命科學領(lǐng)域的一個核心細胞信號轉(zhuǎn)導是研究細胞感受并轉(zhuǎn)導環(huán)境(也包含內(nèi)環(huán)境)刺激、調(diào)節(jié)代謝生理反應(yīng)和基因表達的分子途徑的一門科學。生命科學研究論文發(fā)表最集中的領(lǐng)域之一全球藥物開發(fā)四分之一集中的領(lǐng)域HistoryOverview1951 NGF(1stgrowthfactor)1957 cAMP(1971Nobel)Phosphorylation;Proteinkinase(1992Nobel)

1960 EGF(1980Nobel)1970’ Gprotein;Gprotein-coupledreceptor(1994Nobel)1978 Src(1stproteintyrosinekinase)1986 Rb(1sttumorsuppressorgene)1990’ Cross-talkNobelPrizesinSignalingStudy信號轉(zhuǎn)導與腫瘤一、信號轉(zhuǎn)導的概念和基本組成二、信號轉(zhuǎn)導系統(tǒng)的特征三、重要的信號轉(zhuǎn)導通路四、腫瘤信號轉(zhuǎn)導的異常五、以信號轉(zhuǎn)導為靶的腫瘤治療六、常用的信號轉(zhuǎn)導研究方法七、發(fā)展方向細胞信號轉(zhuǎn)導指細胞通過細胞表面（或胞內(nèi)）受體接受外界信號，通過系統(tǒng)級聯(lián)傳遞機制，將胞外信號轉(zhuǎn)導為胞內(nèi)信號，最終引起細胞生理反應(yīng)或特定基因的表達，引起細胞伯應(yīng)答反應(yīng)，這種特定的反應(yīng)系統(tǒng)稱之為細胞信號通路一、信號轉(zhuǎn)導的概念和基本組成概念信號受體

信號轉(zhuǎn)導級聯(lián)通路細胞核（轉(zhuǎn)錄因子染色體）基因表達蛋白質(zhì)表達譜的改變信號傳導過程生物效應(yīng)信號識別信號轉(zhuǎn)導ExtracellularfactorsMembranereceptorsAdaptorproteinsSecondmessengersIntracellularkinasesTranscriptionfactors基本組成刺激細胞增殖的因子1) GrowthFactors

(家族性；受體為酪氨酸激酶；相對特異性；多樣性）2) Cytokines(ILs,CSFs,IFN)

(受體不具酪氨酸激酶活性） 3)Hormones,Neurotransmitters (通過GPCR傳遞信號）其它細胞外因子 TNFs,Adhesionmolecules(Fibronectin,Laminin, Collagen)ExtracellularFactors生長因子受體

酪氨酸激酶(tyrosinekinase)

EGFR,IGFR,PDGFR,FGFR,NGFR,HGFR

G蛋白耦聯(lián)受體(GPCR)

最大的受體家族 7-transmembrane

無激酶活性，通過G蛋白傳導信號細胞因子受體 1）淋巴細胞表面受體(TCR,BCR) 2)白介素受體 3）細胞凋亡受體(Fas,TNFR)粘附因子受體

1）Cadherins 2)Integrins 3)Igsuperfamily 4)SelectinsMembraneReceptors生長因子受體142012EGFRsignaling

本身不具有催化活性，在信號轉(zhuǎn)導通路中起著重要的橋梁作用，將被配體激活的受體與其下游的信號轉(zhuǎn)導分子相連接，溝通整條信號轉(zhuǎn)導通路。AdaptorProteinsAdaptorProteinDomainsPTB:Phosphotyrosinebindingdomain(BindP-tyrosine)SH2:Src-homologydomain2(BindP-tyrosine)SH3:Src-homologydomain3(BindProline-richmotif(PXXP))PH:Pleckstrinhomology(PIP2phospholipidbinding)WW:BindPXPX,P-serineorP-threoninePDZ:Bindhydrophobic residuesatC-terminusFYVE:BindPtdIns-3P

DD:Deathdomain;apoptosis 定義：細胞外因子與受體結(jié)合后，在細胞內(nèi)產(chǎn)生的具有生物活性的小分子。

種類：cAMP,cGMP,DAG,IP3,Ca2+

功能：

cAMPPKA cGMPPKG DAGPKC Ca2+(calmodulin)CAMKI,II,III&MLCKSecondMessengersVeryimportantforsignalingSerine/ThreoninekinasesImportantkinases

Mitogen-activatedproteinkinse(MAPK) ProteinKinaseA(activatedbycAMP) ProteinKinaseG(activatedbycGMP) ProteinKinaseC(activatedbyDAG) CAMK(activatedbyCa2+/Calmodulin) PI3K(Growthfactorreceptor)IntracellularKinases特異性網(wǎng)絡(luò)性，多樣性通路之間的多層次交流(cross-talk)不同的信號可以激活同一條轉(zhuǎn)導通路同一信號往往能夠激活多條轉(zhuǎn)導通路二、信號轉(zhuǎn)導系統(tǒng)的特征三、重要的信號轉(zhuǎn)導通路MAPKPathwayBiologicalEffectProliferationStressApoptosisInflammationRAS-RAF-MEK-MAPK?Ligandbindsreceptor?LigandbindsreceptorPTK?AutophosphorylationontyrosinePPPPRAS-RAF-MEK-MAPK?LigandbindsreceptorPTK?Autophosphorylationontyrosine?GRB2(aSH2-andSH3-containingprotein)bindstothereceptorphosphotyrosinemotifY-V/L-N-XviaitsSH2domainPPPPRAS-RAF-MEK-MAPKSH2SH3GRB2SOS?LigandbindsreceptorPTK?Autophosphorylationontyrosine?GRB2(aSH2-andSH3-containingprotein)bindstothereceptorphosphotyrosinemotifY-V/L-N-XviaitsSH2domain?TheSH3ofGRB2bindsconstitutivelytotheproline-richsequenceintheC-terminusofSOS(aguaninenucleotideexchangefactorforRAS).

PPPPSH2SH3GRB2SOSRAS-RAF-MEK-MAPK?RecruitmentofSOStothecloseproximityofRASinthemembranePPPPSH2SH3GRB2SOSRASGDPRAS-RAF-MEK-MAPK?RASbecomesactivatedbyexchangingGDPforGTPPPPPSH2SH3GRB2SOSGDPGTPRASRAS-RAF-MEK-MAPK?TheRAS-GTPeffectordomaininteractswiththeN-terminalregulatoryregionoftheRAF(serine/threonineproteinkinase),hencerecruitingRAFtothemembranePPPPSH2SH3GRB2SOSRASGTPRAFRAS-RAF-MEK-MAPK14-3-3?ActivationofRAF(mostlikelybyphosphorylationofRAFandbindingtothescaffoldprotein14-3-3)PPPPSH2SH3GRB2SOSRASGTPRAFRAS-RAF-MEK-MAPK14-3-3?ActivatedRAFinturnactivatesMEK(alsocalledMAPKkinase;adualspecificitykinase)byphosphorylationontwoconservedserineresiduesinMEK.PPPPSH2SH3GRB2SOSRASGTPRAFMEKPPRAS-RAF-MEK-MAPK14-3-3?ActivatedMEKactivatesMAPK(aserine/threonineproteinkinase)byphosphorylationofconservedthreonineandtyrosineresidues.PPPPSH2SH3GRB2SOSRASGTPRAFMEKPPMAPKPPRAS-RAF-MEK-MAPK14-3-3?ActivatedMAPKphosphorylatesanumberofsubstratesintheplasmamembraneandthecytoplasm;PPPPSH2SH3GRB2SOSRASGTPRAFMEKPPMAPKPPSubstratesSubstratesPPRAS-RAF-MEK-MAPK14-3-3?ActivatedMAPKphosphorylatesanumberofsubstratesintheplasmamembraneandthecytoplasm;italsotranslocatedintothenucleus(withinmin)whereitphosphorylatesnucleartranscriptionfactors.PPPPSH2SH3GRB2SOSRASGTPRAFMEKPPSubstratesRAS-RAF-MEK-MAPKMAPKPPMAPKPP14-3-3?ActivatedMAPKphosphorylatesanumberofsubstratesintheplasmamembraneandthecytoplasm;italsotranslocatedintothenucleus(withinminutes)whereitphosphorylatesnucleartranscriptionfactors.

Transcriptionofgenesimportantforcellproliferation.PPPPSH2SH3GRB2SOSRASGTPRAFMEKPPRAS-RAF-MEK-MAPKSubstratesMAPKPPMAPKPPPDephosphorylationbytyrosinephosphatasesBindingofinhibitoryproteinsEndocytosisDegradationTerminationofSignalTransductionPKC:ProteinkinaseCPTP:ProteintyrosinephosphataseUb:Ubiquitin四、腫瘤信號轉(zhuǎn)導的異常多階段(Multiplestages)：激發(fā)、促進、進展和轉(zhuǎn)移多通路(Multiplepaths)：增殖、分化、凋亡、侵襲與轉(zhuǎn)移多基因(Multiplegenes)：瘤基因、抑瘤基因、損傷修復相關(guān)基因、細胞周期調(diào)控基因腫瘤的發(fā)生是一個涉及多個階段、多條通路、多個基因的病理過程腫瘤的本質(zhì)特征自己自足的生長信號抗生長信號不敏感抵抗細胞死亡潛力無限的復制能力持續(xù)的血管生成組織浸潤和轉(zhuǎn)移避免免疫摧毀促腫瘤炎癥細胞能量異?；蚪M不穩(wěn)定和突變Self-SufficiencyinGrowthSignalsInsensitivitytoAntigrowthSignalsResistingCellDeathLimitlessReplicativePotentialSustainedAngiogenesisTissueInvasionandMetastasisAvoidingImmuneDestructionTumorPromotionInflammationDeregulatingCellularEnergetics1.RoleofTGF-binCarcinogenesis2.NF-kBinCarcinogenesis3.Wnt/b-cateninPathway4.ErbB/HERinCarcinogenesis5.PI3K/AktinCarcinogenesis五、以信號轉(zhuǎn)導為靶的腫瘤治療所謂靶向治療(targetedtherapy)就是將靶向藥物與對促進腫瘤形成和發(fā)展有重要作用的蛋白相結(jié)合，抑制這些蛋白的功能，從而減緩腫瘤細胞的增殖和侵襲轉(zhuǎn)移等特性，達到治療腫瘤的目的。腫瘤信號轉(zhuǎn)移通路的研究

——使腫瘤靶向治療成為可能抗信號轉(zhuǎn)導治療針對信號轉(zhuǎn)導系統(tǒng)各組成部分受體激酶連接蛋白轉(zhuǎn)錄因子組合靶標/信號通路MechanismofActionofImatinibMesylate(STI-571;Gleevec)HER2過表達細胞Trastuzumab與HER2受體結(jié)合生長信號

被阻斷抑制腫瘤

細胞生長Trastuzumab作用：

靶標抗癌藥物就是針對分子靶點的抗癌藥物，這類藥物的針對性強，效果顯著。改變了傳統(tǒng)化療藥物對所有快速分裂的細胞全面打擊的方式。這類藥物的出現(xiàn)，標志著癌癥治療新時代的開始。研究熱點集中在針對細胞表面靶標的單克隆抗體和信號轉(zhuǎn)導抑制劑。Proteinexpression Westernblot √ Proteinphosphorylation

Kinaseassay √DNA-proteininteraction

Gelshiftassay(Mobilityshiftassay) Rep