Clusterin: Review of research progress and looking ahead to direction in hepatocellular carcinoma

Liver cancer, a large proportion of which is hepatocellular carcinoma (HCC), is diagnosed in more than 700000 people each year worldwide. Liver cancer is particularly prevalent in Asia, Sub-Saharan Africa and the South Pacific, where hepatitis B and hepatitis C infection rates are very high. However, due to resistance to chemotherapy, patients with intermediate and advanced-stage disease cannot benefit from this treatment. Clusterin, which is overexpressed in many different cancers, is a stress-induced cytoprotective protein that confers treatment resistance. Custirsen (OGX-011) is a novel 2'-methoxyethyl modified phosphorothioate antisense oligonucleotide that targets secretory clusterin protein expression and is currently in clinical trials for patients with different cancers. In recent years, a number of different clinical trials have been performed, and two phase III clinical trials of custirsen evaluating combinations with chemotherapy in patients with metastatic castration-resistant prostate cancer and metastatic non-small cell lung cancer are currently in progress. The aims of this review are to summarize the current state of research on clusterin, predict future research directions and analyze the potential of the clinical application of custirsen in HCC.