Involvement of SENP1 protein in resistance of dacarbazine in melanoma

Abstract

Objective  To investigate the genes and signaling pathways associated with drug resistance in melanoma and establish their relationship with melanoma drug resistance. Methods  A375 and M14 melanoma cells were used as the experimental model to develop a drug-resistant melanoma cell line by gradually increasing the concentration of dacarbazine (DTIC). Transcriptomics was employed to analyze significant changes in genes and pathways within the drug-resistant melanoma cell line. Real-time quantitative polymerase chain reaction (RT-qPCR) and Western blotting(WB) were conducted to validate the altered genes.  Results  (1) Successful construction of melanoma drug-resistant cell lines: drug-resistant cell lines,namely A375 and M14,were successfully established by gradually increasing the dosage of DTIC. The determination of their the half maximal inhibitory concentration (IC50) values to DTIC indicated a significant change in cell sensitivity. Flow cytometry analysis revealed that drug-resistant melanoma cells exhibited a notable ability to resist apoptosis induced by DTIC. (2) Identification of genes and signaling pathways associated with melanoma drug resistance: transcriptomic analysis by the established DTIC-resistant melanoma cell lines demonstrated that increased expression of SENP1 was correlated with abnormal activation of the Hippo signaling pathway. (3) Implication of aberrant expression of ubiquitin-specific protease SENP1 in DTIC resistance: WB analysis of wild-type and drug-resistant melanoma cell lines revealed upregulation of both SENP1 and YAP expressions in drug-resistant cells. (4) The involvement of SENP1 in DTIC resistance was confirmed by gene knockout and the effect of SENP1 on ubiquitination of YAP was preliminarily confirmed by protein interaction experiments. Conclusion  A positive correlation existed between SENP1 and DTIC resistance in melanoma,which may contribute to alterations in the Hippo signaling pathway and enhance melanoma tolerance to DTIC. 

Keywords

melanoma / drug resistance / transcriptome / Ubiquitin-like specific proteases / Hippo signaling pathway