Abstract:Multiple myeloma (MM) is a malignant tumor of the hematological system caused by abnormal proliferation of plasma cells in bone marrow. The progression of the disease is strongly regulated by immunosuppressive tumor microenvironment (TME), which is beneficial to the spread of tumor cells. The survival of patients have been greatly improved with the clinical application of new drugs. At present, several T cell-based immunotherapies, such as bispecific antibodies, immune checkpoint inhibitors and chimeric antigen receptor T-cell immunotherapy (CAR-T), are successfully entering the field of immunotherapy with very promising results in clinical trials. However, similar to what has been observed in clinical chemotherapy, MM cells appear to be able to evade immunotherapy, especially through interaction with the bone marrow microenvironment. This paper summarizes the changes in cellular composition and related signaling pathways in bone marrow microenvironment during the disease progression, in order to explain the potential mechanism of immune escape of MM cells mediated by the bone marrow microenvironment.