However, some cytokines have dual effects on tumors; IL-6 and IL-8 can directly suppress MM cells or recruit immunosuppressive cells to the tumor microenvironment or promote tumor angiogenesis, such as myeloid-derived suppressor cells (MDSCs), regulatory T cells (T regs) and tumor-associated macrophages (TAMs). Here, CXCL8 is linked to Miyoshi myopathy.