Expression And Implication Of Activating Transcription Factor5in Colorectal Adenocarcinoma

AIM:To investigate the expression of ATF5(Activating Transcription Factor5) and Bcl-2(B-cell lymphoma/Leukemia-2) in colorectal adenocarcinoma.Methods:RT-PCR and S-P staining was used to examine the mRNA and protein expression level of ATF5and Bcl-2in56colorectal adenocarcinoma and adjacent tissues.Result:The expression levels of both ATF5and Bcl-2mRNA in colorectal adenocarcinoma tissues were higher than the adjacent tissues(P<0.01). And they were related to the differentiation degree and Dukes clinical stagermore ATF5mRNA was detected in poorly differentiated adenocarcinoma tissues than well/moderately differentiated adenocarcinoma tissues(P<0.05) and more in Dukes stage C-D than stage A-B(P<0.05):conversely,less Bcl-2mRNA in poorly differentiated adenocarcinoma tissues than well/moderately differentiated ones(P<0.05) and less in Dukes stage C-D than stage A-B(P <0.05).The immunohistochemistry study indicated that most of the adenocarcinoma tissues(45/56) showed cytoplasm immunoreactivity for ATF5while only a few cells located at the basal part of the lacune showed ATF5staining in adjacent tissues(8/56).Similarly,more colorectal adenocarcinoma tissues (30/56)showed Bcl-2staining than adjacent(5/56). The protein expression levels of both ATF5and Bcl-2were related to the differentiation degree and Dukes clinical stage too,just like the result of RT-PCR.Conclusion:The abnormal expression of ATF5may play an important role in the development and progression of colorectal adenocarcinoma. As it was related to the differentiation and Dukes clinical stage,it can be a new index to predict the prognosis and targeting ATF5may be a potential selective approach for colorectal adenocarcinoma therapy.ATF5may play it’s role by regulating the expression of Bcl-2in colorectal adenocarcinoma.