SOX13 promotes colorectal cancer metastasis by transactivating SNAI2 and c-MET.

Metastasis is a major cause of high recurrence and poor survival of patients with colorectal cancer (CRC), although the mechanisms associated with this process remain poorly understood. In this study, we report a novel mechanism by which SOX13 promotes CRC metastasis by transactivating SNAI2 and c-MET. SOX13 overexpression was significantly correlated with more aggressive clinicopathological features of CRC and indicated poor prognosis in two independent cohorts of CRC patients (cohort I, n = 363; cohort II, n = 390). Overexpression of SOX13-promoted CRC migration, invasion, and metastasis, whereas SOX13 downregulation caused the opposite effects. Further mechanistic investigation identified SNAI2 and MET as important target genes of SOX13 using serial deletion and site-directed mutagenesis luciferase reporter and chromatin immunoprecipitation (ChIP) assays, as well as functional complementation analyses. In addition, SOX13 was shown to be a direct target of HGF/STAT3 signaling, and the c-MET inhibitor crizotinib blocked the HGF/STAT3/SOX13/c-MET axis, significantly inhibiting SOX13-mediated CRC migration, invasion and metastasis. Moreover, in clinical CRC tissues, SOX13 expression was positively correlated with the expression of SNAI2, c-MET, and HGF. CRC patients with positive coexpression of SOX13/SNAI2, SOX13/c-MET, or HGF/SOX13 exhibited a worse prognosis. In summary, SOX13 is a promising prognostic biomarker in patients with CRC, and blocking the HGF/STAT3/SOX13/c-MET axis with crizotinib could be a new therapeutic strategy to prevent SOX13-mediated CRC metastasis.