The emerging role of FAM46C as a biomarker and therapeutic target in gastric adenocarcinoma.

On a global scale, gastric adenocarcinoma (GCa) accounts for a large burden of death from cancer. Despite advances in systemic therapy and surgical technique, the fatality rate for GCa remains unacceptably high in Europe and North America, where diagnosis is typically made at an advanced stage. Biomarkers that can accurately predict response to new therapies and provide novel therapeutic strategies are urgently sought. FAM46C, a putative noncanonical nucleotidyltransferase, has garnered interest for its tumor suppressor function in multiple myeloma. A frequent and profound depletion of FAM46C has been described in GCa patients from China, Japan and now Canada. Furthermore, the degree of FAM46C depletion meaningfully portends cancer recurrence following resection, and death from GCa. In this review, we provide an updated summary of the literature regarding FAM46C as a biomarker in GCa and explore the potential mechanism(s) through which FAM46C depletion promotes GCa progression, including dis-inhibition of oncogenic Plk4 kinase activity. We highlight the potential for restoration of FAM46C levels as a therapeutic strategy. Norcantharidin, a synthetic analogue of the traditional Chinese medicine cantharidin derived from the blister beetle, is the only bio-available compound presently known to upregulate FAM46C expression and is under investigation in phase one trials in cancer patients.