Lenalidomide, a drug used in the treatment of MM, has been shown to affect the PD-1/PD-L1 axis by downregulating the expression of PD-L1 on MM cells [9, 13] and by decreasing the levels of regulatory T cells and T-cell expression of PD-1 [13, 70, 71]. This evidence concerns the gene PDCD1 and Miyoshi myopathy.