P-122 Expression of apurinic/apyrimidinic endonuclease 1 in colorectal cancer and its relation to tumor progression and prognosis

Apurinic/apyrimidinic endonuclease 1 (APE1) functions in the base excision repair pathways of DNA damage and acts as a redox regulator many transcriptional factors. Overexpression APE1 have been demonstrated to be associated with cancer progression chemoresistance various cancers. Therefore, our study aimed examine expression its relation tumor prognosis patients colorectal (CRC). We investigated 193 CRC receiving curative surgery which usage formalin-fixed paraffin-embedded blocks possible, long term tumor-specific survival rate analysis possible. The was by reverse transcription-polymerase chain reaction, western blotting, immunohistochemistry lymph node tissues. apoptosis, proliferation, angiogenesis cells were determined performing terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay, immunohistochemical staining for Ki-67, CD34 antibodies. overexpressed tissues compared paired normal tissue at mRNA protein levels. significantly advanced stage, lymphovascular invasion, perineural deeper metastasis, distant poor survival. Multivariate that APE1, invasion metastasis independent prognostic factors overall mean Ki-67 index value APE1-positive tumors higher than APE1-negative tumors. However, there no significant difference between apoptotic or microvessel density. These findings indicate overexpression is patients. may novel biomarker present potential factor CRC.