MMP9 and colorectal carcinoma: Circ-APLP2 has been proven to act as a miR-101-3p sponge to regulate the Notch1 signaling pathway in CRC and activate proliferation and metastasis-related signals (c-Myc, cyclin D1, MMP-2, and MMP-9), thereby promoting the proliferation and liver metastasis of CRC (96).