Expression And Significance Of Tumor Suppressor And Apoptosis Genes In Mucosa-associated Lymphoid Tissue Lymphoma: Application Of Tissue Microarray Technique

[Aim] To investigate the protien expression and significance of cell cycle and apoptosis genes in mucosa- associated lymphoid tissues (MALT) lymphoma. [Methods] Tissue arrayer was used to create a 252-dot tissue microarray, consisting of 84 cases of malignant lymphomas arising in esophagus, stomach, intestines, thyroid, saliva gland , orbital cavity and lung, Seven cases of diffuse large B cell lymphomas(DLBCL),9 adenocarcinomas, 1 neuroendocrine tumor,1 squamous carcinoma, 6 T-cell lymphomas and 18 reactive lymphoid nodes were also included as control in the microarray. An immunohistochemical staining (S-P method) was performed to examine the expression of these proteins in all cases.[Result] The expression of Ki-67 and TopoII a were significantly different in clinical stages in L-MALT lymphoma and increased with the more advanced stages (p<0.05) . The index of mutated p53 was no difference among clinical grades in L-MALT lymphomas (x2 =3.058, p =0.217) , but was significantly different between L- and H-MALT lymphomas. Expression of p53 was positively correlated with the malignant degree (r=0.502, p=0.000) . The expression of Bcl-2 and Bax in L-MALT lymphomas was significantly different from that of in H-MALT lymphomas. Bcl-2 expression in the L-was higher than that in the H-MALT lymphomas. On the contrary , Baxexpressed in the H- was higher than that in the L-MALT lymphomas. P53 had the obverse correlation to Bcl-2 in L-MALT lymphomas (r=0.385, p<0.05) . No significantly different expression of C-myc was found in clinical stage in MALT lymphomas. Whereas the cytoplasm expression of c-myc increased with the malignancy (r=0.431, p=0.000) . In L-MALT, H-MALT and DLBCL, mutated p53 was obversely correlated with cytoplasm expression of c-myc ( r=0.365 , p=0.000 ) and reversely correlated with nuclear expression of c-myc ( r=-0.301 , p=0.004 ) . BCL-10 abundantly expressed in germinal central in lymphoid follicular. Cytoplasm expression rate of BCL-10 in L- was lower than that in H-MALT lymphomas (x2=6.197, p=0.013) . Seven cases of MALT lymphomas and 1 DLBCL had the nucleolus expression. Among them 6 cases occurred infiltration in fat tissue and muscle except one case of thyroid which lymphoma cell limited in situ. And the patient attacked DLBCL befallen infiltration in boron marrow and central nerve system and died within 3 months. Only 5 cases expressed the EBV in 84 cases of MALT lymphomas[Conclusion] Ki-67 , Topo II a can be acted as one of the prognostic factor in L-MALT lymphomas; combining p53 and the cytoplasm expression of c-myc we may estimate the prognosis of MALT lymphoma ; Expression of Bcl-2 maybe the early event of the rumor ; higher cytoplasm expression rate of Bcl- 10 may represent the higher malignant degree and nuclear expression of Bcl- 10 may bear on the aggression. EBV did not play a major role in MALT lymphoma.