Expression Of Mismatch Repair Protein In Follicular Lymphoma

Objective: Observe the differential expression of MMR protein in FL of differentgrade, the differential expression of MMR protein between follicular andinterfollicular; analysis the correlation between the differential expression of CD10and MMR protein follicular and interfollicular, the relationship between MMRprotein expression deletion and the occurrence of FL without both t(14;18)chromosomal translocations and BCL-2expression. To explore the role of MMRdefect in pathogenesis and development process of FL, provide some materials forfurther clear of molecular mechanisms of occurrence and development of FL.Methods: All tissues investigated in this study were obtained from Jiangxi provincialpeople’s hospital and Queen Elizabeth Hospital of Hong Kong between2007-2012,include routine and consultation cases, a total of one hundred and sixteen cases of FLand twenty cases of FRH. Expression of CD20, CD3, BCL-2, CD10and ki-67in FLand FRH were detected by MaxvisionTM2/HRP two-step immunohistochemicalstaining method, the t(14;18) chromosomal translocations in FL were detected byFISH, expression of MMR protein（MLH1, MSH2, MSH6and PMS2） in neoplasticB cells both follicular and interfollicular in FL and in follicular B cells of FRH weredetected by DouSPTMdouble immunohistochemical staining method. To explore thedifferential expression of MMR protein in FL of different grade; the differentialexpression of MMR protein in follicular and interfollicular; the correlation betweenthe differential expression of CD10and MMR protein follicular and interfollicular;the relationship between MMR protein expression deletion and the occurrence of FLwithout both t(14;18) chromosomal translocations and BCL-2expression. Chi-squaretest was used to analyze the comparison of the rate of immunohistochemical variables,non-parametric Spearman rank correlation analysis was used to analyze therelationship between two factors.Results:(1) The negative rates of MLH1and MSH2protein expression in FL werehigher than in FRH (P<0.05); there were no significance differences between thenegative rate of MSH6or PMS2protein expression in FL and FRH (P>0.05).(2) Thenegative rate of MLH1or MSH2protein expression in FL which were both negative for t(14;18) and BCL-2expression was higher than that which were both positive;there were no significant differences between the negative rates of MSH6or PMS2protein expression in FL which were both negative for t(14;18) and BCL-2expression and both positive (P>0.05).(3) The negative rate of MLH1and MSH2protein expression in FL of grade3was higher than in FL of grade2(P<0.05), therewere no significant differences between the negative rates of MLH1and MSH2protein expression in FL of other grades(P>0.05); the were no significant differencesbetween the negative rates of MSH6and PMS2in FL of different grades(P>0.05).(4)The negative rates of MLH1、MSH2、MSH6and PMS2protein expression ofneoplastic B cells were significant higher in interfollicular than in follicular (P<0.05).(5)The were no correlations between the differential expression of CD10and theMLH1、MSH2、MSH6and PMS2protein follicular and interfollicular(P>0.05).Conclusions:(1) The negtive rates of MMR protein expression deletion in highergrade FL were higher than that in lower grade FL, the negative rates of MMR proteinexpression of neoplastic B cells were higher in interfollicular than that in follicular, sowe spectulate that MMR protein expression deletion may play a role in theprogression of FL.(2) The were no correlations between the differential expression ofCD10and the MMR protein follicular and interfollicular, so we spectulate that MMRprotein expression deletion was not the resean of the weaker expression of CD10ininterfollicular.(3) The negative rate of MMR protein expression in FL which wereboth negative for t(14;18) and BCL-2expression were higher than that which wereboth positive, so we spectulate that MMR protein expression deletion may havesomething to do with FL which are negative for t(14;18).