Bone marrow mesenchymal stromal cells and multiple myeloma: Cellular interactions and therapeutic opportunities.

Bone marrow mesenchymal stromal cells (BM-MSCs) are essential components of the bone marrow microenvironment that support hematopoietic cells and play key roles in immune regulation, tissue repair, and regeneration. In addition to their capacity to differentiate into mesodermal lineages, BM-MSCs exhibit significant immunomodulatory effects. The role of BM-MSCs in the pathobiology of multiple myeloma (MM) has been a focus of research, as these cells promote the survival, proliferation, and retention of plasma cells in the bone marrow through various molecular interactions. Proteomic and genomic characterisation of BM-MSCs in patients with multiple myeloma (MM) has revealed aberrant gene expression, dysregulated cytokine production, and an immunosuppressive phenotype, all of which promote MM cell proliferation and treatment resistance. Several alternative treatment approaches for MM targeting BM-MSCs, including disruption of cell-cell communication, inhibition of soluble growth factors, and the development of immunotherapies such as CAR-T cells, are under investigation.