High expression of AZGP1 is associated with poor prognosis in colorectal cancer: a retrospective study

Abstract Background Alpha-2-glycoprotein 1, zinc-binding (AZGP1) is a 41 kDa secreted glycoprotein that has been considered as a potential prognostic biomarker. High expression of AZGP1 in serum is considered to be an indicator of poor prognosis in CRC, however further validation in tissue specimens is lacking. Methods We detected the expression level of AZGP1 in 859 CRC patients and 210 normal mucosa samples by immunohistochemistry and analyzed the relationship between AZGP1 expression and clinicopathological parameters of CRC patients. The relationship between AZGP1 and overall survival of patients was also analyzed to verify the prognostic value of AZGP1 in CRC patients. Multivariate analysis of prognostic factors in CRC patients using Cox proportional hazards regression models. Results The high expression rate of AZGP1 in colorectal adenocarcinoma was 48.4% higher than that in adjacent mucosal tissues and 13.3% (P<0.001). The expression level of AZGP1 was related to the depth of invasion ( P <0.001), lymph node metastasis ( P =0.023), distant metastasis ( P =0.002) and pTNM stage( P =0.003). Univariate analysis found that histological type, differentiation, invasion, lymph node metastasis, distant metastasis, pTNM stage and AZGP1 expression were associated with the prognosis of CRC patients (all P < 0.05). Multivariate analysis suggested lymph node metastasis (95% CI : 0.331-0.775, HR : 0.506, P =0.002), distant metastasis (95% CI: 0.126-0.293, HR : 0.192, P <0.001) and AZGP1 (95% CI : 0.262-0.637, HR : 0.408, P <0.001) were independent prognostic indicators. Conclusion AZGP1 is a useful indicator for predicting the prognosis of CRC. Its predictive effect is weaker than that of lymph node metastasis and distant metastasis.