APC and colorectal carcinoma: miR-135a/b is also predicted to target and inhibit secreted frizzled-related protein 4 (SFRP4), the latter is a Wnt/β-catenin inhibitor through binding and repressing extracellular Wnt proteins [34].On the other hand, miR-135b can be transcriptionally activated by β-catenin/TCF4, which shows that miR-135b is significantly upregulated in human CRC and in the tumors of an Apc mutation mouse model [35].