Lectin from Agrocybe aegerita as a Glycophenotype Probe for Evaluation of Progression and Survival in Colorectal Cancer


Background: Agrocybe aegerita Lectin (AAL) has been identified to have high affinity for sulfated and α2-3-linked sialic acid glycoconjugates, especially the sulfated and sialyl TF (Thomsen-Friedenreich) disaccharide. Thisstudy was conducted to investigate the clinicopathological and prognostic value of AAL in identifying aberrantglycosylation in colorectal cancer (CRC). Materials and
Methods: Glycoconjugate expression in 59 CRC tissueswere detected using AAL-histochemistry. Clinicopathological associates of expression were analyzed with chisquaretest or Fisher’s exact test. Relationships between expression and the various clinicopathological parameterswas estimated using Kaplan-Meier analysis and Cox regression models.
Results: AAL specific glycoconjugateexpression was significantly higher in tumor than corresponding normal tissues (66.1% and 46.1%, respectively,p=0.037), correlating with depth of invasion (p=0.015) and TNM stage (p=0.024). Patients with lower expressionlevels had a significantly higher survival rate than those with higher expression (p=0.046 by log rank test andp=0.047 by Breslow test for overall survival; p=0.054 by log rank test and P=0.038 by Breslow test for progressfree survival). A marginally significant association was found between AAL specific glycoconjugate expression andoverall survival by univariate Cox regression analysis (p=0.059).
Conclusions: Lower AAL specific glycoconjugateexpression is a significant favorable prognostic factor for overall and progress free survival in CRC. This is thefirst report about the employment of AAL for histochemical analysis of cancer tissues. The binding characteristicsof AAL means it has potential to become a powerful tool for the glycan investigation and clinical application.