Cancer increases the global disease burden substantially, but it remains a challenge to manage it. The search for novel biomarkers is essential for risk assessment, diagnosis, prognosis, prediction of treatment response, and cancer monitoring. This paper examined NEDD8 ultimate buster-1 (NUB1) and F-adjacent transcript 10 (FAT10) proteins as novel biomarkers in cancer. This literature review is based on the search of the electronic database, PubMed. NUB1 is an interferon-inducible protein that mediates apoptotic and anti-proliferative actions in cancer, while FAT10 is a ubiquitin-like modifier that promotes cancer. The upregulated expression of both NUB1 and FAT10 has been observed in various cancers. NUB1 protein binds to FAT10 non-covalently to promote FAT10 degradation. An overexpressed FAT10 stimulates nuclear factor-kappa β, activates the inflammatory pathways, and induces the proliferation of cancer. The FAT10 protein interacts with the mitotic arrest deficient 2 protein, causing chromosomal instability and breast tumourigenesis. FAT10 binds to the proliferating cell nuclear antigen protein and inhibits the DNA damage repair response. In addition, FAT10 involves epithelial-mesenchymal transition, invasion, apoptosis, and multiplication in hepatocellular carcinoma. Our knowledge about them is still limited. There is a need to further develop NUB1 and FAT10 as novel biomarkers.