To verify the PMEPA1 signature in BLCA, we focused on PMEPA1 expression, relationship with clinical parameters and immune cells in BLCA, and the IHC result in the Xiangya cohort showed that the macrophages (in the central tumor and peritumoral stroma) were strongly associated with PMEPA1 expression. Here, PMEPA1 is linked to bladder transitional cell carcinoma.