ABSTRACT
Objective To study the synergistic antitumor effects of quercetin and cisplatin in human prostate cancer PC3 cells and LNCaP cells.Methods Twelve h after PC3 cells or LNCaP cells were seeded,different dose of quercetin (10 μmol/L,20 μmol/L,40 μmol/L,80 μmol/L,160 μmol/L) or cisplatin (0.01 μmol/L,0.05 μmol/L,0.1 μmol/L,1 μmol/L,10 μmol/L),or quercetin (20 μmol/L) + cisplatin (0.01 μmol/L,0.05 μmol/L,0.1 μmol/L,1 μmol/L,10 μmol/L) were added for48 h and then the antiproliferative effects were detected with MTT assay.After incubated with quercetin (20 μmol/L) or cisplatin (0.05 μ mol/L),or quercetin (20 μ mol/L) + cisplatin (0.05 μmol/L) for48 h,cell cycle distribution and apoptosis of PC3 cells or LNCaP cells were detected by flow cytometer,PI and Annexin V staining.Protein expression was detected by Western blotting.Results After treatment with quercetin or cisplatin alone,the IC50 were (0.99 ± 0.13) μmol/L,(0.75 ± 0.09) μmol/L and (91.60 ± 6.10) μ mol/L,(72.90±4.70) μ mol/L for LNCaP cells or PC3 cells,respectively;The IC50 were (0.11±0.06)μ mol/L,(0.07±0.02) μmol/L for quercetin + cisplatin treatment (Compared with quercetin,P＜0.01 ;Compared with cisplatin,P＜0.05.After treatment with cisplatin or quercetin + cisplatin for 48 h,the S phase percent of LNCaP cells or PC3 cells were (22.4±2.7)％,(31.2±2.4)％ and (20.1±1.6)％,(31.0±2.5)％,respectively,(Compared with control,P＜0.05,however,treatment with quercetin alone has no significant difference (Compared with control,P＞0.05).After treatment with cisplatin or quercetin + cisplatin for 48 h,the apoptotic percent of LNCaP cells or PC3 cells were (14.8 ± 1.9) ％,(39.6 ± 3.1) ％ and (11.5± 1.2) ％,(34.1 ±3.3) ％,respectively,(compared with control,P ＜ 0.05,however,treatment with quercetin alone had no significant difference (compared with control,P＞0.05).After treatment with quercetin alone for 48 h,the activation of caspase-3,caspase-8 and caspase-9 were slightly increased,the expressions of Bax and p21 were up-regulated,the expressions of Bcl-2 and CDK2 were down-regulated.Furthermore,these effect of cisplatin and quercetin + cisplatin were significantly enhanced (compared with quercetin,P＜0.05;compared with quercetin,P＜0.01,respectively.Conclusions The combination modality with quercetin and cisplatin has a better treatment effect in vitro not only in androgen-dependent LNCaP cells but also in androgen-independent PC3 cells.