Altered Serum Annexin A2 Might Be a New Potential Diagnostic Biomarker in Human Colorectal Cancer

Objective. Annexin A2 is a calcium dependent phospholipid binding protein that is a biomarker in cancers. However, the value of serum Annexin A2 in the diagnosis of colorectal cancer (CRC) is not clear. This study aimed to investigate clinical utility of serum Annexin A2 as a potential biomarker for CRC. Methods. Annexin A2 was analyzed in 20 cases of CRC tissues and 20 controls of normal adjacent paired tissues. Serum Annexin A2 was calculated in 59 CRC patients and 44 healthy subjects. Receiver operating characteristic (ROC) curve and logistic regression were utilized to evaluate the diagnostic effectiveness and construct diagnostic model. Results. Annexin A2 in CRC tissues was slightly higher than in normal adjacent paired tissues (chi 2=6.0652, p<0.05). Serum Annexin A2 in CRC patients was significantly lower than in healthy controls (p<0.05). Besides, the levels of serum Annexin A2 were lower in patients with poor tumor differentiation than in well or moderate tumor differentiation (p=0.0111). ROC analysis indicated the diagnostic efficacy of serum Annexin A2 was better than carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA199) for CRC. Furthermore, joint detection of Annexin A2 and CEA had the maximum area under the ROC curve (AUC) in discriminating CRC from healthy controls (AUC 0.931, sensitivity 86.4%, specificity 84.7%, positive predictive value 87.9%, and negative predictive value 82.2%). Conclusions. Serum Annexin A2 may be a non-invasive and promising biomarker for the diagnosis of CRC, and the joint detection of Annexin A2 and CEA may have been favorable clinical applied value in the diagnosis of CRC.