Functional analysis of Cullin 3 E3 ligases in tumorigenesis

• Published in: Biochimica et biophysica acta. Reviews on cancer 2018-01, Vol.1869 (1), p.11-28
• Main Authors: Cheng, Ji, Guo, Jianping, Wang, Zhiwei, North, Brian J., Tao, Kaixiong, Dai, Xiangpeng, Wei, Wenyi
• Format: Article
• Language: English
• Subjects: Animals; Carcinogenesis - genetics; Carcinogenesis - metabolism; Cullin 3; Cullin Proteins - genetics; Cullin Proteins - physiology; Humans; Keap1; Mouse models; SPOP; Tumorigenesis; Ubiquitin; Ubiquitin-Protein Ligases - genetics; Ubiquitin-Protein Ligases - physiology; Ubiquitination - genetics
• ISSN: 0304-419X; 1879-2561
• DOI: 10.1016/j.bbcan.2017.11.001

Cullin 3-RING ligases (CRL3) play pivotal roles in the regulation of various physiological and pathological processes, including neoplastic events. The substrate adaptors of CRL3 typically contain a BTB domain that mediates the interaction between Cullin 3 and target substrates to promote their ubiquitination and subsequent degradation. The biological implications of CRL3 adaptor proteins have been well described where they have been found to play a role as either an oncogene, tumor suppressor, or can mediate either of these effects in a context-dependent manner. Among the extensively studied CRL3-based E3 ligases, the role of the adaptor protein SPOP (speckle type BTB/POZ protein) in tumorigenesis appears to be tissue or cellular context dependent. Specifically, SPOP acts as a tumor suppressor via destabilizing downstream oncoproteins in many malignancies, especially in prostate cancer. However, SPOP has largely an oncogenic role in kidney cancer. Keap1, another well-characterized CRL3 adaptor protein, likely serves as a tumor suppressor within diverse malignancies, mainly due to its specific turnover of its downstream oncogenic substrate, NRF2 (nuclear factor erythroid 2-related factor 2). In accordance with the physiological role the various CRL3 adaptors exhibit, several pharmacological agents have been developed to disrupt its E3 ligase activity, therefore blocking its potential oncogenic activity to mitigate tumorigenesis. •CRL3s display various neoplastic roles depending on their substrate specificity.•Keap1 functions as an anti-tumor adaptor of CRL3s mainly through degrading NRF2.•SPOP acts as a context-dependent adaptor in a variety of malignancies.•CRL3-targeted therapy is a promising strategy against diverse neoplastic events.