We collected 27 samples from patients with newly diagnosed MM (NDMM), and 5 samples from relapsed refractory MM (RRMM) patients with exposure to lenalidomide. The results showed that compared with NDMM, the expression of CCL20 mRNA in RRMM was lower (p < 0.01...CCL20 could therefore possibly increase the sensitivity of lenalidomide and Elotuzumab.