Detection And Significance Of Chromosome Abnormalities Where Bcl-2 And Bcl-6 Genes Locating In DLBCL

BackgroundDiffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin's lymphomas, which represents approximately 30% to 59% of these disorders.Recently, using cDNA microarray technology, DLBCL can be divided into prognostically significant subgroups with germinal center B-cell-like (GCB), activated B-cell-like (ABC), or type 3 gene expression profiles. The GCB group has a significantly better survival than the ABC group, The type 3 group is heterogeneous and not well defined, but has a poor outcome similar to the ABC group. So now we simply devide DLBCL into two groups:GCB and non-GCB. The GCB represents the group with better prognosis, whereas the non-GCB represents the worse.Since 2002, attentions have been placed on the prognostic value of protein expression and progresses have been achieved. In 2004, using the cDNA microarray results as a golden standard, Hans et al found that the expression of CD10, BCL-6 and MUM1 can be combined to divide cases of DLBCL into GCB and non-GCB subgroups with an outcome closely related to prognosis.According to the WHO, detection of genetic abnormalities is the most reliable method for the classification of malignant lymphomas. New genetic method using fluorescent-labelled DNA, FISH, is of great value to the diagnosis of genetic abnormalities. Most researchers abroad use thin paraffin embedded tissue sections in FISH detection, which is easily available and can be compared with the corresponding HE stained sections for the correct allocation of the desired regions. Whereas, this method can inevitably lead to the overlaps, or even the destructions of nuclei, which can result in the error of the detection. What's more, paraffin and fixatives in the tissues can't be removed completely so that the binding of DNA and probes may be blocked.Chromosomal regions with obvious different DNA copy numbers between tumor cells and normal ones can be obtained by scanning the entire genome based on CGH. We constructed tree models of multi-steps and multi-pathways process of DLBCL tumorigenesis by analysing CGH results in different labs recent years. We classified DLBCL into 3 types based on the tree models we constructed. Three genes, CD10(3q25.1-q25.2), BCL-6(3q27) and MUM1 (6p25-p23), used for the...