Expression And Clinicopathological Significance Of AID Protein In Diffuse Large B Cell Lymphoma

Objective:To investigate the expression of AID in diffuse large B cell lymphoma and its relationship with clinicopathologic parameters,immunophenotype,cytogenetics and prognosis.Methods:All tissues investigated in this study were obtained from patients (n=101) who underwent initial treatment between 2003 and 2008 in Jiangxi Province People's Hospital.101 cases of DLBCL tissue and 15 cases of reactive hyperplasia lymphoid tissue were made into 3 tissue microarrays.The expression of AID in tissue microarray were detected by MaxVisionTM/HRP immunohistochemical method.The colocalized expression of AID and CD20,Ki-67 in DLBCL were detected by DouSPTM immunohistochemical double staining method.BCL6 gene rearrangement were detected by fluorescence in situ hybridization. Clinicopathologic parameters and immunochemical data were analyzed by Chi-square and Fisher exact probability tests. The relationships of two factor were analysed by non-parametric Spearman rank correlation analysis. The calculation and comparison of survival rate of DLBCL were analysed by Kaplan-Meier method and Log-Rank test of univariate survival analysis.Results:(1)The positive rate of AID expression was 26.7% in DLBCL,AID mainly express at dark zone of germinal center in reactive proliferation of lymphoid tissue. (2) By colocalized expression analysis of AID and CD20,the expression of AID were found heterogeneity in tumorous B cell.(3) Among 101 cases of DLBCL, The positive rate of AID expression in cases of age exceed or equal 60 was significantly higer than in cases of age less than 60(P<0.05), the expression of AID had no significant relationship with gender,sites of involvement and morphologic variants(P>0.05).(4) The expression of AID had no relationship with immunohistochemistry subgroup (P>0.05) (5) The expression of AID had positive correlation with expression of P53(p<0.05),but had no correlation with CD10,BCL6 and MUM1(P>0.05). (6) The expression of AID had positive correlation with BCL6 gene rearrangement,Ki-67 proliferation index(Ki-67>50%).(7) Among 101 cases of DLBCL, survival data of 42 cases were acquired, the 5-year survival rate of the AID positive patients was lower than the AID negative patients, the difference between them had statistical significance (P=0.042).Conclusions:(1) The positive expression of AID had associated with poor prognosis of DLBCL;(2) The expression of AID had positive correlation with BCL6 gene rearrangement in DLBCL,to hint that AID have a role in BCL6 gene rearrangement.