The role of ubiquitin-specific protease 14 (USP14) in cell adhesion-mediated drug resistance (CAM-DR) of multiple myeloma cells.

OBJECTIVE

Cell adhesion-mediated drug resistance (CAM-DR) is one of the mechanisms underlying the drug resistance in multiple myeloma (MM). Ubiquitin-specific protease 14 (USP14) is downregulated in the apoptotic model and upregulated in the adhesive model of MM. This study was undertaken to determine the role of USP14 in CAM-DR of MM cells.

METHODS

We examined the expression of USP14 in the apoptotic model of MM. The mechanism of USP14 in the process of apoptosis was further explored by flow cytometry assay and co-immunoprecipitation. We then performed the cell co-culture and adhesion assay and cell viability assay to investigate the effect of USP14 on adhesive rate and drug resistance in MM.

RESULTS

We discovered that USP14 played a negative role in cell apoptosis, which is correlated with Bcl-xl. Moreover, overexpression of USP14 in MM cell adhesion model could enhance the ability of cell adhesion by regulating Wnt-signaling pathways, thereby promoting the CAM-DR in MM.

CONCLUSIONS

USP14 participates in CAM-DR of MM through acting as a bridge between Bcl-xl apoptotic pathway and Wnt-signaling pathways and may be represented as a good candidate for pursuing clinical trials in MM.