Abstract
BACKGROUND: It has generally been proven that histone acetylation and deacetylation are involved in the malignant transformation. To date, however, this has rarely been studied in cases of malignant lymphoma. METHODS: We studied nine cases of reactive lymphoid hyperplasia, 78 cases of diffuse large B-cell lymphoma (DLBCL), 13 cases of peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS), and 13 cases of extranodal NK/T-cell lymphoma, nasal type (NKTCL). Thus, we attempted to elucidate the associations of the degree of the expression of histone acetyltransferase 1 (HAT1), histone deacetylase (HDAC) 1, HDAC2, and HDAC3 with the clinical behaviors of above malignant lymphomas using the immunohistochemistry and a western blot analysis. RESULTS: The degree of the expression of HAT1 was higher in cases of DLBCL, PTCL-NOS or NKTCL as compared with reactive lymphoid hyperplasia (p<0.05). The degree of the expression of HAT1 was correlated with that of HDAC1 in cases of DLBCL or NKTCL (p<0.05). The degree of the expression of HAT1 and HDAC1 was correlated with a poor survival in cases of DLBCL or PTCL-NOS (p>0.05). CONCLUSIONS: HAT1, HDAC1, and HDAC2 play a critical role in the development of malignant lymphomas. Both HAT1 and HDAC1 might be indicators for a poor prognosis in cases of DLBCL as cooperating factors.