Hypoxia-induced DTL promotes the proliferation, metastasis, and sorafenib resistance of Hepatocellular Carcinoma through Notch Signaling Pathway

Abstract

Denticleless E3 ubiquitin protein ligase homolog (DTL), the substrate receptor of the CRL4A complex, plays a central role in genome stability. Even though the oncogenic function of DTL has been investigated in several cancers, its specific role in Hepatocellular Carcinoma (HCC) still needs further elucidation. Data from a clinical cohort (n = 209), RNA-sequencing, and public database (TCGA and GEO) were analyzed, indicating that DTL is closely related to patient prognosis and could serve as a promising prognostic indicator in HCC. Functionally, DTL promoted the proliferation, metastasis, and sorafenib resistance of HCC in vitro. In the orthotopic tumor transplantation and tail vein injection model, DTL promoted the growth and metastasis of HCC in vivo. Mechanically, we revealed for the first time that DTL was transcriptionally activated by hypoxia-inducible factor 1α (HIF-1α) under hypoxia and functioned as a downstream effector molecule of HIF-1α. DTL facilitates HCC cell proliferation, metastasis, and epithelial-mesenchymal transition through the Notch pathway. These results suggested that DTL may be a potential biomarker and therapeutic target for HCC.