RESUMO
Objective To investigate the suppression effect, the apoptosis and TGF-β_1 mRNA expression of rhDCN and dororubicin(ADM) on leukemic K562 cell line. Methods K562 cells in Logarithmic growth phase were divided into Saline group, pcDNA3.1 (+)-DCN group, ADM group, and pcDNA3.1 (+)-DCN-ADM group. Morphology change of cell was detected by Wright stain, cell proliferation activity was assessed by MTT. The apoptosis index of K562 cells was assessed by FCM, and TGF-β_1 mRNA of cell was assessed by RT-PCR. Results Wright stain showed that more pronounced morphological apoptosis changes of K562 cells in combined group. MTT method results showed that the proliferation inhibition rate of the combined group was (61±1.32) % higher than that of individual intervention group [DCN group, (20±1.90) %; ADM group, (47±1.04) %](P <0.05). FCM results showed that the apoptosis index of the combined group was (61.30± 0.9) %, higher than that of Individual intervention group [DCN group, (28.25±1.3) %; ADM group, (31.85± 1.5) %](P <0.05). TGF-β_1 mRNA synthesis of combined group was significantly decreased. Conclusion rhDCN can markedly enhance cytotoxicity of ADM on K562 cells, and the mechanisms of apoptosis may be due to down-regulation of TGF-β_1 mRNA. Specific mechanisms will be further studied.