Study Reveals Tumor and Immune Cell Changes in Advanced Multiple Myeloma

A team led by researchers from the Max Delbrück Center have made strides in understanding the progression of multiple myeloma. The study, published in Science Immunology, focused on how tumor cells diversify and interact with immune cells after breaking through the bone marrow.

Multiple myeloma often develops unnoticed over decades. In its advanced stages, lesions can form, damaging bones and spreading cancer. The team investigated these lesions to understand what occurs when myeloma cells exit the bone marrow. They found that tumor cells undergo drastic diversification upon leaving the bone, which appears to help them adapt to new environments and spread further.

According to senior author Niels Weinhold, “We suspect that this diversity helps the cancer cells adapt to survival outside the bone, enabling them to spread to other areas of the body.” 

Using advanced single-cell and spatial omics technologies, the researchers analyzed immune system responses to this "outbreak" of cancer cells. They observed notable changes in immune cell types and numbers within the microenvironment of these lesions. For instance, T cells in affected areas exhibited altered receptors and surface molecules, potentially adapting to the tumor's increased heterogeneity.

“There seems to be a co-evolution between tumor and immune cells, in which both sides react to changes in the other,”  explained co-author Simon Haas. This interaction may influence disease progression positively or negatively. The team is now exploring which factors impact this dynamic.

The study also revealed that diagnostic samples taken from the pelvis may not fully represent the disease's complexity. Lesion-specific sampling could provide more precise diagnostics and inform tailored therapies.