Development of the optimal therapies based on molecular genetics of multiple myeloma

1.多发性骨髓瘤中新染色体易位的鉴定：1)t(1;14)(p34;q32)：通过基因组克隆分离ODA细胞的1p34断点，发现E3/LAPTm5基因在表达上存在断裂。2)t(1;14)(p34;q32)：通过基因组克隆分离ODA细胞的1p34断点，发现其第一个内含子E3/LAPTm5基因被破坏。有趣的是，这个基因在60%的骨髓瘤细胞系中表达被关闭。该现象是由基因调控序列的高甲基化引起的。MGUS/smoldering multiple myeloma（SMM）患者的2.14q32易位采用双色fish分析方法对16例MGUS/SMM患者纯化浆细胞的14q32染色体易位进行了检测。56%的病例携带14q32易位，其中三分之二在14q32（IgH）和11q13（CCND1）位点之间，并伴随CyclinD1.3的核表达。鉴定多发性骨髓瘤不同的发育途径：建立CCND1、FGFR3、MUM1、c-MAF、MAFB和c-MYC基因的定量RT-PCR检测方法，应用于19个细胞系和30份骨髓瘤样本的研究。该研究确定了至少三种不同的多发性骨髓瘤发育途径，这些途径起源于CCND1、FGFR3和c-MAF/MAFB基因的表达改变。

1.Identification of novel chromosomal translocations found in multiple myeloma :1)t(1;14)(p34;q32) : 1p34 breakpoint of ODA cells was isolated by genomic cloning and found to have disrupted E3/LAPTm5 gene in terms of its expression. This phenomenon was caused by hypermethylation of the regulatory sequences of the gene.2)t(1;14)(p34;q32) : 1p34 breakpoint of ODA cells was isolated by genomic cloning and found to have disrupted E3/LAPTm5 gene in the first intron. Interestingly, this gene was shut off in 60% of the myeloma cell lines in terms of its expression. This phenomenon was caused by hypermethylation of the regulatory sequences of the gene.2.14q32 translocations in MGUS/smoldering multiple myeloma(SMM)Purified plasma cells derived from 16 MGUS/SMM patients were examined concerning 14q32 chromosomal trans locations by means of double color-FISH analysis. 56% of the cases carried 14q32 translocations, in which two thirds were between 14q32(IgH) and 11q13(CCND1) loci with concomitant nuclear expression of CyclinD1.3.Identification of the distinct developmental pathways of multiple myeloma :Quantitative RT-PCR assay was established for CCND1, FGFR3, MUM1, c-MAF, MAFB and c-MYC genes, and applied for the study of 19 cell lines and 30 myeloma samples. It led to the identification of at least three distinct developmental pathways of multiple myeloma, which originated from altered expression of CCND1, FGFR3 and c-MAF/MAFB genes.