HNF4A and colorectal carcinoma: Furthermore, results of the TOP/FOP flash assay, which reflects the transcriptional activity of β-catenin-TCF, showed that STEAP3-AS1 knockdown significantly weakened the transcriptional activity of β-catenin-TCF in CRC cells (Fig. 6F), whereas enhanced expression of STEAP3-AS1 increased the activity (Fig. 6G).