The change of F-18 FDG and H-3 PCV uptakes after transduction of micro RNA for hexokinase II and HSV1-sr39 gene in cancer cells

Objectives Overexpression of hexokinase II (HK II) that catalyzes the initial metabolic step of glycolysis is reported in various cancer cells. Here, we have evaluated the changes in F-18 FDG and H-3 PCV uptake after transfection of a vector containing micro RNA (miRNA) for HK II mRNA and HSV1-sr39 as a reporter gene in the 293 and HCT15 cells.

Methods We have engineered three candidates of miRNA for isoenzymes of human Type II hexokinase (HK-II) and prepared stable cells expressing both miRNA for HK-II and GFP gene in HCT15 and ARO cells. Inhibition of HK-II expression by each miHKII was assessed by RT-PCR, western blot analysis and F-18 FDG uptake. A vector construct containing the miRNA for HK-II gene and HSV1-sr39tk cDNA coupled CMV promoters, was designed as THKII. Expression of two genes was evaluated with using F-18 FDG and H-3 PCV uptakes in 293 and HCT15 stable cells in vitro.

Results In the miHKII transfected cells, the level of mRNA and protein for HK-II-1, 2 and 3 was decreased compared to parent cells. Decreased cellular uptake of F-18 FDG was observed in transfected cells and those were positively correlated with the level of HKII expression. Transfection of THKII to the 293 and HCT15 cells resulted in 14- and 4-fold increases in H-3 PCV uptake than those control cells, while decreased F-18 FDG uptake about 35% and 40% compared to control cells.

Conclusions Transfection of a vector containing miRNA for HK II mRNA and HSV1-sr39 gene resulted in increased H-3 PCV uptake and decreased F-18 FDG uptake in cancer cells, and those are correlated with the level of HK-II expression.