RNA Binding Protein RNPC1 Inhibits Breast Cancer Cell Metastasis via Activating STARD13-Correlated ceRNA Network

RNA binding proteins (RBPs) are pivotal post transcriptional regulators. RNPC1, an RBP, acts as a tumor suppressor through binding and regulating the expression of target genes in cancer cells. This study disclosed that RNPC1 expression was positively correlated with breast cancer patients' relapse-free and overall survival and that RNPC1 suppressed breast cancer cell CDH5 metastasis. Mechanistically, RNPC1 promotes competing endog-HOXDIO STARD13-correlated enous RNA (ceRNA) network crosstalk among STARD13, STARD13 ceRNA network CDH5, HOXD10, and HOXD1 (STARD13-correlated ceRNA HOXD1 network), which we previously confirmed in breast cancer cells through stabilizing the transcripts and thus facilitating the expression of these four genes in breast cancer cells. Furthermore, RNPC1 overexpression restrained the promotion of STARD13, CDH5, HOXD10, and HOXD1 knockdown on cell metastasis. Notably, RNPC1 expression was positively correlated with CDHS, HOXD1, and HOXD10 expression in breast cancer tissues and attenuated adriamycin resistance. Taken together, these results identified that RNPC1 could inhibit breast cancer cell metastasis via promoting a STARD13-correlated ceRNA network.