RT-qPCR showed the expression of CHI3L1, IL-10, RETNLB (Fizz1), and Arg1, to confirm the M2 macrophages (Supplementary Figure 1A) The results showed that the expression level of both CD68 and CD206 were significantly increased in cancer tissues compared with paracancerous tissues (Figure 1D). Here, RETNLB is linked to cancer.