Jab1/Cops5: a promising target for cancer diagnosis and therapy.

C-Jun activation domain-binding protein1 (Jab1), the fifth component of the constitutive photomorphogenic-9 signalosome (COPS5/Csn5) complex, functions in several cellular processes to affect different signaling pathways. Dysregulation of Jab1/Csn5 both restrains tumor suppressors and activates oncogenes to contribute oncogenesis. Jab1 overexpressed in various tumors and played an essential part in cancer initiation, progression and prognosis, which has spurred strong research interest in developing inhibitors for cancer therapy. Here, we summarize the multiple signaling pathways and functions of Jab1/Csn5 in tumorigenesis. By querying the Oncomine database, a cancer microarray database and web-based data-mining platform aimed at facilitating discovery from genome-wide expression analyses, we investigated statistically the differential expression of Jab1/Csn5 between different cancer samples and the corresponding normal tissue samples, cancer samples with different histological types, different cancer types, and different clinical outcomes. These statistical data confirmed the significant role of Jab1/Csn5 in carcinogenesis, indicating Jab1/Csn5 as a biomarker and a therapeutic target in different cancers.