Production of DUSP1 protein using the baculovirus insect cell expression system and its in vitro effects on cancer cells.

Abstract

The aim of the present study was to produce the human dual specificity phosphatase 1 (DUSP1) protein with biological activity and to investigate its in vitro effects on cancer cells. DUSP1 protein was expressed in the baculovirus expression system and purified by Ni-affinity chromatography followed by dialysis in PBS. The purified protein was verified by SDS-PAGE and western blot analysis. Six cancer cell lines were then cultured in the presence of DUSP1 for various periods of time, and the phosphorylated extracellular signal-regulated kinase (p-ERK) content in each cell line was subsequently determined by western blot analysis. Compared to the β-actin level, the amount of p-ERK markedly decreased after 1 h, indicating that DUSP1 suppressed the expression of p-ERK in 6 cancer cell lines examined. Human cervical cancer cells were also collected and counted following co-culture with DUSP1 to examine its effect on the growth rate of cancer cells. A baculovirus expression system for the production of DUSP1 protein was successfully constructed. The p-ERK content was found to be significantly decreased when the cancer cell lines were exposed to DUSP1. The capability of binary fission was reduced when the cells were examined under a microscope. The proliferation of human cervical cancer cells was also inhibited by DUSP1.