The pattern of Mesenchymal stem cell expression is an independent marker of outcome in multiple myeloma

Mesenchymal stem cells (MSCs) are an essential component of the bone marrow (BM) microenvironment and have shown to support cancer evolution in multiple myeloma (MM). Despite the increasing evidence that MM MSCs differ from their healthy counterparts, little knowledge exists as to whether MSCs independently influence disease outcome. The aim of the present study was to determine the importance of MSCs in disease progression and outcome in MM. To determine the impact of MSCs on MM outcome in an in vivo system, we first identified genes from cultured MSCs that were specific to MSC expression and were not or minimally expressed in PCs or other cells present in BM aspirates. We then applied this MSC gene signature to whole BM biopsies of MM patients compared to healthy controls and determined MSC expression scores specific to MM and predictive of outcome. Molecular subgroup definitions: CD-1: CCND1/CCND3 (group 5) CD-2: CCND1/CCND3 (group 6) HY: Hyperdiploid LB: Low bone disease MF: MAF/MAFB MS: MMSET PR: Proliferation Discussion of these molecular subgroups is available in: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1895543/