NDRG2genecopynumberisnotalteredincolorectalcarcinoma
摘要: AIMToinvestigateifthedown-regulationofN-mycDownstreamRegulatedGene2(NDRG2)expressionincolorectalcarcinoma(CRC)isduetolossoftheNDRG2allele(s).METHODSThefollowingwereinvestigatedinthehumancolorectalcancercelllinesDLD-1,LoVoandSW-480:NDRG2mRNAexpressionlevelsusingquantitativereversetranscriptionpolymerasechainreaction(qRT-PCR);interactionoftheMYCgene-regulatoryproteinwiththeNDRG2promoterusingchromatinimmunoprecipitation;andNDRG2promotermethylationusingbisulfitesequencing.Furthermore,weperformedqPCRtoanalysethecopynumbersofNDRG2andMYCgenesintheabovethreecelllines,8normalcolorectaltissuesamplesand40CRCtissuesamples.RESULTSAsexpected,NDRG2mRNAlevelswerelowinthethreecolorectalcancercelllines,comparedtonormalcolon.EndogenousMYCproteininteractedwiththeNDRG2corepromoterinallthreecelllines.Inaddition,theNDRG2promoterwasheavilymethylatedinthesecelllines,suggestinganepigeneticregulatorymechanism.UnalteredgenecopynumbersofNDRG2wereobservedinthethreecelllines.Inthecolorectaltissues,onenormalandthreeCRCsamplesshowedpartialorcompletelossofoneNDRG2allele.Incontrast,theMYCgenewasamplifiedinonecelllineandinmorethan40%oftheCRCcases.CONCLUSIONOurstudysuggeststhatthereductioninNDRG2expressionobservedinCRCisduetotranscriptionalrepressionbyMYCandpromotermethylation,andisnotduetoallelicloss. ...
(共8页)
开通会员,享受整站包年服务