FOXO4 and breast cancer: For example, hsa_circRNA_103809 regulates CRC proliferation and migration via miR-532-3p/FOXO4 axis [16]; hsa_circRNA_101555 is involved in carcinogenesis of breast cancer [17] hsa_circRNA_102619 played a suppressive role in progression of pancreatic ductal adenocarcinoma [18].