We discovered that the infiltration abundance of macrophage M2 was dramatically increased in the group with high ACTA2 (p<0.001), FLNA (p<0.001), TAGLN (p=0.002) and TPM1 (p<0.001) expression compared with the low expression group, which demonstrated a clear correlation between the amount of M2 infiltration and the expression of the four genes in the immune microenvironment of bladder cancer. The gene discussed is FLNA; the disease is urinary bladder cancer.