As shown in Fig. 1A, Pak4 was highly expressed in various tumors, including bladder urothelial carcinoma (BLCA), breast invasive carcinoma (BRCA), cholangiocarcinoma (CHOL), Esophageal carcinoma (ESCA), head and neck cancer (HNSC) and so on. Here, PAK4 is linked to invasive breast carcinoma.