Effects of suppressor of cytokine signaling 1 silencing on human melanoma cell proliferation and interferon-γ sensitivity.

The aim of the current study was to observe the effects of suppressor of cytokine signaling 1 (SOCS1) silencing in human melanoma cells on cell biological behavior and interferon-γ (IFN-γ) sensitivity, and to investigate the use of SOCS1 as a therapeutic target in the treatment of melanoma. Western blot analysis and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) were used to verify that SOCS1 interference effectively silenced the expression of SOCS1 in the Mel526 human melanoma cell line. For IFN-γ stimulation, western blot analysis was used to observe changes in expression levels of signal transduction and transcription activator (STAT) 1 and phosphorylated STAT (pSTAT) 1. Changes in the expression levels of IFN-γ regulatory factor 1 (IRF-1) were measured with RT-qPCR. Changes in the sensitivity of melanoma cells to IFN-γ were detected using an MTT assay. The cell proliferation rate was observed by cell counting and changes in the cell cycle were detected with flow cytometry. The results revealed that SOCS1 interference effectively silences SOCS1 expression in Mel526 cells. However, the S stage of the cell cycle was markedly extended. Following the inhibition of SOCS1 expression, the proliferation experiment demonstrated that the proliferation ability of Mel526 cells was decreased. Following IFN-γ stimulation, the expression levels of pSTAT and IRF-1 increased significantly compared with those in the controls. The MTT experiment showed that SOCS1 interference caused the median inhibitory concentration (IC50) of oxaliplatin in Mel526 cells to decrease significantly. In conclusion, SOCS1 interference reduced the proliferation ability of Mel526 human melanoma cells and increased their sensitivity to IFN-γ.