Interferon gamma-induced hub genes and key pathways: A study based on biological network analysis and experimental validation

By performing a biological network analysis, we identified some hub genes, which were up- or down-regulated in the breast cancer (BC) cell line after treatment with IFN-γ. Moreover, several pathways including cytokine-cytokine receptor interaction, TNF signaling pathway, NOD-like receptor signaling pathway, and NF-κB signaling pathway were detected that their activation leads to the antiproliferation, proapoptosis, and antiviral activities. To validate in silico results, the bioactivity of recombinant human IFN-γ (hIFN-γ) produced in different hosts was analyzed by antiviral and anticancer assays. The antiviral role of the hIFN-γ preparations was evaluated by inhibition of Vesicular Stomatitis Virus (VSV)-mediated cytopathic effects on Vero cells. A dose-dependent increase in cell viability was observed at different concentrations of recombinant proteins. The maximum amount of the cell viability detected for the hIFN-γ preparations was determined at a concentration of 32.00 pg/mL. To analyze the cytotoxic efficacy of the hIFN-γ preparations on the growth and development of tumor cells, a BC cell line (MCF-7) was treated with both recombinant protein forms in a time- and dose-dependent way. The highest level of inhibiting cell proliferation was detected at a concentration of 32.00 pg/mL hIFN-γ after 72 h incubation. Anticancer and antiviral functions of IFN-γ were confirmed via the expression analysis of hub genes cd74, cxcl10, il6, and stat1 using RT-PCR. Furthermore, the hIFN-γ preparations were significantly able to up-regulate the expression of proapoptotic Bax and p53 and to down-regulate Bcl-2 as an antiapoptotic gene, showing the cytotoxic effect of hIFN-γ toward MCF-7 cells via apoptosis induction.