Abstract
MicroRNAs (miRNAs) are a class of small non-coding RNA molecules that regulate a countless number of genes in the cell, and the aberrant expression of miRNA can lead to cancer. Here, we demonstrate that miR-101-3p regulates the RPL11-MDM2-p53 pathway by targeting ubiquitin-specific peptidase 47 (USP47), consequently inhibiting cancer cell proliferation. We confirm that miR-101-3p directly binds to the 3'-UTR region of the USP47 gene and inhibits USP47 expression. In addition, the overexpression of miR-101-3p suppresses cell proliferation in a p53-dependent manner. MiR-101-3p promotes interaction between RPL11 and MDM2 by inducing the translocation of RPL11 from the nucleolus to the nucleoplasm, thus preventing the MDM2-mediated proteasomal degradation of p53. However, these phenomena are restored by the overexpression of USP47, but not by its catalytically inactive form. Indeed, miR-101-3p regulates RPL11 localization and its interaction with MDM2 by inhibiting the USP47-induced deubiquitination of RPL11. Finally, the expression of miR-101-3p is downregulated in lung cancer patients, and the patients with low miR-101-3p expression exhibit a lower survival rate, indicating that miR-101-3p is associated with tumorigenesis. Together, our findings suggest that miR-101-3p functions as a tumor suppressor by targeting USP47 and could be a potential therapeutic target for cancers.