This article was originally published here
Sci Rep. 2021 Jul 19; 11 (1): 14671. doi: 10.1038 / s41598-021-93835-z.
Extramedullary disease (EMM) represents a rare, aggressive and especially resistant phenotype of multiple myeloma (MM). EMM is frequently associated with high-risk cytogenetics, but their complex genomic architecture is largely unexplored. We used whole genome optical mapping (Saphyr, Bionano Genomics) to analyze the genomic architecture of CD138 + cells isolated from bone marrow aspirates of an unselected cohort of patients newly diagnosed with EMM (n = 4) and intramedullary MM (n = 7). Large intrachromosomal rearrangements (> 5 Mbp) within chromosome 1 were detected in all EMM samples. These rearrangements, mainly deletions with / without inversions, encompassed hundreds of genes and resulted in changes in the copy number of genes on large regions of chromosome 1. Compared to intramedullary MM, EMM was characterized by more than deletions (size range 500 bp to 50 kbp) and fewer interchromosomal translocations, and two EMM samples exhibited copy number loss in the 17p13 region. Generalized genomic heterogeneity and new aberrations in IGH / IGK / IGL high risk regions, 8q24 and 13q14 were detected in individual patients but were not specific to EMM / MM. Our pilot study revealed an association of chromosome 1 abnormalities in myeloma cells of the bone marrow with extramedullary progression. Optical mapping has shown the potential to refine the complex genomic architecture in MM and its phenotypes.
PMID: 34282158 | DOI: 10.1038 / s41598-021-93835-z