Objective:ToexaminetheexpressionsofMDM2,P53andP27proteinsinchronicesophagitis,para-cancermucosaandesophagealcarcinoma.Methods:ImmunohistochemistrywasusedtodetecttheexpressionsofMDM2,P53andP27proteinsinforty-sevenpatientssufferingfromchronicesophagitisandeighty-fivecasesofesophagealcarcinomaandcorrespondingpara-cancermucosa.Flowcytometry((FCM)wasappliedtodetectthequantitiesoftheseproteinsexpressedinfreshtissuesof48casesofesophagealcancerandtheirpara-cancertissuesand24casesofrelativenormalmucosaatthesurfaceofcuttingedge.Results:Immunohistochemistryresultsshowedthattheexpressionsofthethreestudiedproteinswereverysimilarintheepitheliaofchronicesophagitisandpara-cancermucosa(P>0.05).BoththequalitativeandquantitativestudiesdisplayedthattheP53proteinhadnoexpressionanditsaccumulationswouldappearonlyintheearlystagesofesophaguscancerationwhiletheMDM2andP27proteinshaddifferentdegreesofexpressionsincasesofnormalesophagealmucosa.MDM2proteinmarkedlyincreasedintheadvancedstagesofesophagealcanceration.AquantitativestudyshowedthattheexpressionofP27proteinhadalinearityofdecreasingtendency(F=9.132,P=0.002)inthecourseofesophagealcanceration.Conclusion:Chronicesophagitismaybeaprecancerouslesion.OwingtothechangesoftheP53andP27proteins,wecanalsoconcludethattheseoccurintheearlystagesofesophagusoncogenesis,howeverthechangesofMDM2expressionmayoccurintheadvancedstageofesophagealcanceration.
