Circular RNA hsa_circ_0001178 facilitates the invasion and metastasis of colorectal cancer through upregulating ZEB1 via sponging multiple miRNAs.

Metastasis is the main cause of increasing cancer morbidity and mortality. However, the underlying mechanism of cancer metastasis remains largely unknown. In the present study, we identified one circular RNA (circRNA) closely related to the metastasis of colorectal cancer (CRC), namely hsa_circ_0001178. CRC patients with high hsa_circ_0001178 were more prone to have metastatic clinical features, advanced TNM stage and adverse prognosis. Stable knockdown of hsa_circ_0001178 significantly weakened CRC cell migratory and invasive capabilities in vitro as well as lung and liver metastases in vivo. Mechanistic study revealed that hsa_circ_0001178 acted as a competing endogenous RNA (ceRNA) for miR-382/587/616 to upregulate ZEB1 (a key trigger of epithelial-to-mesenchymal transition), thereby promoting CRC metastatic dissemination. Of note, ZEB1 could also increase hsa_circ_0001178 expression via physically binding to hsa_circ_0001178 promoter region. Collectively, our data uncover the crucial role of hsa_circ_0001178 in CRC metastasis, and targeted therapy based on this positive feedback ceRNA axis may be a promising treatment for metastatic CRC patients.