DCAF13 promotes ovarian cancer progression by activating FRAS1-mediated FAK signaling pathway

Cullin-RING ubiquitin ligase 4 (CRL4) is closely correlated with the incidence and progression of ovarian cancer. DDB1- and CUL4-associated factor 13 (DCAF13), a substrate-recognition protein in the CRL4 E3 ubiquitin ligase complex, is involved in the occurrence and development of ovarian cancer. However, its precise function and the underlying molecular mechanism in this disease remain unclear. In this study we confirmed that DCAF13 is highly expressed in human ovarian cancer and its expression is negatively correlated with the overall survival rate of patients with ovarian cancer. We then used CRISPR/Cas9 to knockout DCAF13 and found that its deletion significantly inhibited the proliferation, colony formation, and migration of human ovarian cancer cells. In addition, DCAF13 deficiency inhibited tumor proliferation in nude mice. Mechanistically, CRL4-DCAF13 was found to target Fraser extracellular matrix complex subunit 1 (FRAS1) for polyubiquitination and proteasomal degradation. FRAS1 was found to influence the proliferation and migration of ovarian cancer cell through induction of the focal adhesion kinase (FAK) signaling pathway. These findings collectively show that DCAF13 is an important oncogene which promotes tumorigenesis in ovarian cancer cells by mediating FRAS1/FAK signaling. Our findings pave the way to develop new potential targeted therapeutics for ovarian cancer treatment.