LAUSR

Squamous cell carcinoma (SCC) is nonmelanoma skin cancer, which is very common in patients having T‐cell immunosuppressant drugs. Anticancerous agents such as cytokines showed effective response on SCC. Human interferon‐gamma (hIFN‐γ), a type II cytokines, are having potent antiproliferative and immunomodulatory effects. In the current study, the fed‐batch cultivation of recombinant Pichia pastoris was carried out, and its effect on cell biomass production, recombinant human interferon‐gamma (rhIFN‐γ) production, and the overflow metabolites was estimated. P. pastoris GS115 strain coexpressed with 6‐phosphogluconolactonase (SOL3) and ribulose‐phosphate 3‐epimerase (RPE1) gene (GS115/rhIFN‐γ/SR) resulted in 60 mg L−1 of rhIFN‐γ production, which was twofold higher as compared with the production from GS115/rhIFN‐γ strain. The antiproliferative potential of rhIFN‐γ was examined on the human squamous carcinoma (A431) cell lines. Cells treated with 80 ng mL−1 of rhIFN‐γ exhibited 50% growth inhibition by enhancing the production of intracellular reactive oxygen species levels and disrupting membrane integrity. Our findings highlight a state of art process development strategy for the high‐level production of rhIFN‐γ and its potential application as a therapeutic drug in SCC therapy.