IGH/MAFB Translocation, Dual Fusion LPH044 - Detail

The t(14:20) translocation is one of seven recurrent IGH translocations that are referred to as primary oncogenic events in around 73% of multiple myeloma cases¹. These translocations result in a transcription product that dysregulates further controlling genes such as the cyclin family of cell cycle control genes which then disrupts normal cell division. In the case of the t(14;20) translocation, the reciprocal rearrangement brings a truncated form of the IGH μ-Enhancer (Eμ, located between the Joining (J) segments and the constant region of the IGH gene) in close contact with the MAFB gene². The resultant fusion and the up-regulated transcription product has been shown to cause overexpression of CyclinD3 in around 7% of tumours³. Of the seven translocation partners of IGH in Multiple Myeloma (including CCND1, CCND2, CCND3, c-MAF, MAFA and FGFR3/MMSET), MAFB has a prevalence of around 2%⁴. The three genes in the MAF family provide equally poor prognosis for patients and a similar phenotype but the MAFB translocation shows a different prevalence in Multiple myeloma patients (2%) compared to MGUS/SMM cases as around 7% of these tumours have the rearrangement⁵.

Reference:/Bibliographie/Literatur/Bibliografia

1. Avet-Loiseau H et al (2002) Blood 99: 2185-2191
2. Boersma-Vreugdenhil GR et al (2004) B. J. Haematology 126: 355-363
3. Bergesgagel PL et al (2005) Blood 106: 296-303
4. Zhan F et al (2007) Blood 109: 1692-1700
5. Chng W et al (2007) Best Pract. Res. Clin. Haematol. 20: 571-596