Wild-type PTEN gene enhances the inhibitory effect of artesunate on K562 cell growth

AIM: To investigate the effect of wild-type PTEN transfection on the sensitivity of human leukemia K562 cells to artesunate (ART) and its molecular mechanism. METHODS: The adenovirus containing wild-type PTEN (Ad-WT-PTEN) or empty vectors (Ad) were transfected into K562 cells[with multiplicity of infection (MOI)=200]. The untransfected cells served as normal control. The effect of wild-type PTEN on the inhibition of K562 cell growth by ART was observed. The sensitizing ratio of PTEN combined with ART based on IC₅₀ was calculated. The viability of K562 cells was detected by MTT assay. The apoptosis was analyzed by flow cytometry. The mRNA level of PTEN was assessed by real-time PCR. The protein expression of PTEN, p-Akt and Akt was detected by Western blot. The activity of caspase-3/7 was measured by caspase activity kits. RESULTS: The sensitivity of K562 cells to ART was significantly increased by 2.25 folds after transfected with PTEN based on the IC₅₀. The cell viability in Ad-WT-PTEN+ART group was significantly lower than that in Ad+ART group after transfection for 3 d (P<0.01). The apoptotic rate in Ad-WT-PTEN+ART group was significantly higher than that in Ad+ART group (P<0.01). The expression of PTEN at mRNA and protein levels in the K562 cells after transfection with PTEN was significantly increased, and the protein level of p-Akt and caspase-3/7 activity were down-regulated, particularly in PTEN combined with ART group. CONCLUSION: The wild-type PTEN gene enhances the sensitivity of the K562 cells to ART by down-regulating the level of p-Akt and up-regulating the caspase-3/7 activity.