MMP2 and neoplasm: Non-coding RNAs reciprocally regulate FN1: tumor-suppressive hsa_circ_0050386 binds SRSF3 to block FN1 pre-mRNA splicing and suppress metastasis [39], while oncogenic Lnc-PDZD7-3 upregulates FN1 to enhance MMP2/9-mediated invasion [40].