Expression And Significance Of Pokemon In Diffuse Large B-Cell Lymphoma And Multiple Myeloma

Objectives:Investigate the expression of Pokemon in diffuse large B-cell lymphoma (DLBCL) and multiple myeloma(MM),To explore the expression of Pokemon and its function in pathogenesis of DLBCL and MM.Methods:Immunohistochemical method(SP) was used to examine the expression of Pokemon,p53,Bcl-6,CD10 and MUM1 protein in 50 cases DLBCL and 10 cases reactive lymphoid hyperplasia(RLH).Pokemon was detected with RT-PCR and Western blot respectively in different cell lines,e g,cervical carcinoma cell line Hela and MM cell line KM3,15 cases of bone marrow mononuclear cells(BMMNCs) of multiple myeloma and 10 cases of peripheral blood mononuclear cells(PBMNCs) of healthy subjects.Results:1.In 50 cases of DLBCL patients,35 cases(70.0%) were found to express Pokemon protein;whereas 1 out of 10 cases was Pokemon protein positive in RLH(10.0%).The expression rate of Pokemon protein in DLBCL was significantly higher than in RLH (P＜0.01).No significant difference of the expression rate of Pokeman protein was found in 20 cases GCB(germinal center origin of B-cell) of DLBCL patients(12/20, 60.0%) and in 30 cases non-GCB(non-germinal center origin of B-cell) patients (23/30,76.7%)(P＞0.05).However,the expression rate of mutant p53 protein in GCB DLBCL(5/20,25.0%) was significantly lower than in non-GCB DLBCL(16/30, 53.3%)(P＜0.05).Among 35 cases of Pokemon protein positive DLBCL patients,18 cases and 16 cases were expressed mutant p53 protein and Bcl-6 protein, respectively.In 15 cases of DLBCL patients Pokemon protein negative,only 3 cases and 2 cases expressed mutant p53 protein and Bcl-6 protein,respectively.The Pokemon protein expression was positively correlated with mutant p53 protein and Bcl-6 protein expression in DLBCL.Pokemon expression was confirmed not to be associated with the DLBCL patients'age,sex and in extranodal or nodal areas.2.Pokemon was over-expressed in MM cell line KM3.In 15 cases of MM patients,6 cases(40.0%) were found to over-express Pokemon in there BMMNCs;whereas 2 out of 10 cases(20.0%) were Pokemon positive in PBMNCs of healthy subjects.The expression rate of Pokemon in BMMNCs of MM was higher than in PBMNCs of healthy subjects by relative quantitative analysis was carried out based on the photodensity ratio(Pokemon/β-actin).Conclusion:1.In our study,significant differences of the expression rates of Pokemon protein were found in 50 cases DLBCL(70.0%) and in 10 cases RLH(10.0%),accorded with the report of Maeda about the expression rate of Pokemon protein in 130 cases DLBCL (60%).The expression rates of Pokemon protein were 60.0%(12/20) and 76.7%(23/30) in GCB and non- GCB DLBCL,respectively.Consequently,the expression rate was higher in non-GCB DLBCL which had worse prognosis than in GCB,nevertheless,had no differences.The expression rate of mutant p53 protein was higher in DLBCL (42.0%) than in RLH(0.0%),the result essentially accorded with the domestic report (38.0%).The positive rate of Pokemon protein had positive relation with the expression rate of mutant p53 protein(P＜0.05),which revealed maybe the synergism of Pokemon and mutant p53 protein participated in the pathogenesis of DLBCL.The Pokemon-p53 pathway may play a role in carcinogenesis and progression of DLBCL. 2.6 cases(40.0%) were found to over-express Pokemon in 15 cases BMMNCs of MM patients by RT-PCR and Western blot,whereas 2 out of 10 cases was Pokemon positive in PBMNCs of healthy subjects(20.0%).Pokemon was over-expressed in MM.