Primary Exploration Of Diagnostic Value Of STAT5of Lung Cancer

Objective:To investigate the expression of STAT5(signal transducer andactivator of transcription5,CEA(carcinoembryonic antig-en) andCyfra21-1(cytokeratin fragment19) in normal human embryonic lungcells MRC-5and lung adenocarcinoma cell A549.The ROC curve wasused to explore the value of STAT5on diagnosis of lung cancer and thepossibility to be a new tumor marker. Methods:1. Expression of proteinof STAT5,CEA and Cyfra21-1in normal human embryonic lung cellsMRC-5and lung adenocarcinoma cell A549were tested byimmunohistochemistry staining (SP). The pictures were analyzed byImage-Pro Plus version6.0(IPP6.0) professional image analysissoftware.The degree of stain was determined by mean opticaldensity(MOD) of sections.2.Using realtime fluores-cence quantitativePCR detects STAT5mRNA,CEA mRNA,Cyfra21-1mRNA in humanlung adenocarcinoma cell line A549and normal human embryonic lungcells MRC-5.ROC curves analy STAT5, CEA, Cyfra21-1protein andmRNA expression in human lung adenocarcinoma cell line A549andnormal human embryonic lung cells MRC-5.Results:1.The results of theimmunohistochemistry：(1)The protein levels of STAT5,CEA andCyfra21-1in lung adenocarcinoma cell A549were apparently higher than that in normal human embryonic lung cells MRC-5.After statisticalanalysis, they had statistically significantdifference(P<0.01).(2)STAT5,CEA,Cyfra21-1andβ-actin were amplifiedrespectively.The amplification efficiency were97.96%、96.77%、95.19%、97.73%.(3)The mRNA levels of STAT5CEA Cyfra21-1in lungadenocarcinoma cell A549were higher than normal human embryoniclung cells MRC-5.(4)The area under ROC curves of STAT5protein andmRNA were0.766and0.807respectively.The of STAT5protein andmRNA were not different compared with each other.(5)The area underROC curves AZof STAT5,CEA,Cyfra21-1mRNA or protein were0.807,0.732,0.721and0.766,0.771,0.749.The AZof STAT5protein andmRNA were not different compared with CEA or Cyfra21-1.(6) STAT5,CEA, CYFRA21-1combined detection can significantly improve theaccuracy of diagnosis of lung cancer, the area under ROC curve of jointdetection of STAT5,CEA and Cyfra21-1was higer than CEA andCyfra21-1.Conclusion:The protein and mRNA of STAT5,CEA,Cyfra21-1expressed in human embryonic cell MRC-5is lower than human lungcancer cell line A549.(2)As a new tumor marker,the diagnotic value ofSTAT5is equivalent to CEA and Cyfra21-1.(3)the combined detectionmethod for early diagnosis of lung cancer has a high value.