Our recent report indicates that FBXO31 functions as a tumor suppressor in gastric cancer, and the loss of FBXO31 protein is associated with a higher malignant phenotype and poorer prognosis.
The SCF<sup>FBXO46</sup> ubiquitin ligase complex mediates degradation of the tumor suppressor FBXO31 and thereby prevents premature cellular senescence.
Ectopic expression of FBXO31 dramatically inhibited xenograft tumor growth in nude mice. miR-20a and miR-17 mimics inhibited, whereas the inhibitor of miR-20a and miR-17 increased, the expression of FBXO31, respectively. miR-20a and miR-17 directly bind to the 3'-UTR of FBXO31.
This study was designed to investigate the expression profile of FBXO31 in HCC and the possibility that FBXO31 might function as a tumor suppressor in HCC cell lines.
One of these factors is an F-box protein, FBXO31, a candidate tumour suppressor encoded in 16q24.3, a region in which there is loss of heterozygosity in breast, ovarian, hepatocellular and prostate cancers.
We propose that FBXO31 functions as a tumor suppressor by generating SCF(FBXO31) complexes that target particular substrates, critical for the normal execution of the cell cycle, for ubiquitination and subsequent degradation.