Construction of SET overexpression vector and its effects on the proliferation and apoptosis of 293T cells

摘要

The expression of SET nuclear proto-oncogene (SET) is commonly associated with cell proliferation and tumorigenesis. In the present study, a eukaryotic SET expression plasmid (pEGFP-N1-SET) was constructed and transiently transfected into 293T human embryonic kidney cells. Transfection led to expression of the SET oncoprotein at high levels, as indicated by polymerase chain reaction and western blot analysis. In addition, the relative mRNA and protein expression of protein phosphatase 2A in pEGFP-N1-SET-transfected 293T cells was downregulated compared with that in empty vector-transfected cells. Furthermore, overexpression of SET increased the percentage of 293T cells in S and G(2)/M phases compared with the control transfectants. An increase in B-cell lymphoma 2 (Bcl-2) and a decrease in Bcl-2-associated X (Bax) protein expression was observed in the pEGFP-N1-SET-transfected cells compared with that in the controls, and their susceptibility to As4S4-induced apoptosis was decreased. The protein SET is involved in a number of cellular processes, including DNA replication, chromatin remodeling, gene transcription, differentiation, migration and cell cycle regulation. SET is overexpressed in several neoplasms, particularly in acute myeloid leukemia. The findings of the present study suggested that the SET gene may contribute to tumorigenesis and may be a potential novel effective therapeutic target for leukemia and other cancer types.