Silencing pyruvate kinase M2 sensitizes human prostate cancer PC3 cells to gambogic acid-induced apoptosis / 中华男科学杂志

ABSTRACT

<p><b>OBJECTIVE</b>To study the effect of silencing pyruvate kinase M2 (PKM2) on gambogic acid (GA)-induced apoptosis of human prostate cancer PC3 cells.</p><p><b>METHODS</b>Three specific PKM2 siRNAs and one negative control siRNA (si-NC) were transfected into PC3 cells. The silencing effect of PKM2 siRNAs was determined by real-time fluorescence quantitative PCR (qRT-PCR) and Western blot, and the effects of PKM2 siRNA on the vitality and apoptosis of GA-stimulated PC3 cells detected by MTT and AO/EB double staining, respectively. The mRNA and protein levels of c-myc and cyclin D1 were analyzed by qRT-PCR and Western blot, respectively.</p><p><b>RESULTS</b>All the 3 PKM2 siRNAs effectively reduced the mRNA and protein expressions of PKM2, and PKM2 siRNA-1 exhibited the strongest silencing effect. At 24 h after transfection, the expression levels of PKM2 mRNA and protein were reduced by 70% and 85%, respectively (P < 0.05). Twenty-four hours of treatment with GA (0.5 micromol/L) following transfection with PKM2 siRNA-1 inhibited the vitality of the PC3 cells by 68%, increased their apoptosis, and significantly down-regulated the mRNA and protein levels of c-myc (50% and 35%) and cyclin D1 (60% and 20%) (P < 0.05).</p><p><b>CONCLUSION</b>Inhibition of PKM2 sensitized PC3 cells to GA-induced apoptosis, suggesting that PKM2 may be a potential therapeutic target for sensitizing human prostate cancer to GA.</p>