BIRC5 and neoplasm: circFAT1 knockdown reduced the mean area immunopositive for YAP1, c-Myc, and Birc5 in tumor tissues, as determined by immunohistochemistry (Fig. 8e), this corresponded to a decrease in the levels of YAP1, c-Myc, and Birc5 protein and mRNA (Fig. 8f and g).