目的：研究RNA干扰沉默核干细胞因子（nucleostemin， NS ）基因表达对人肺腺癌A549细胞株增殖和凋亡的影响。方法：向A549细胞内分别转染靶向 NS 基因的siRNA表达载体pcDNA4/C-NS-silencer和空载体pcDNA4/C vector作为silencer组和vector组，以不转染质粒的A549细胞为normal组，Real-time PCR检测转染pcDNA4/C-NS-silencer对A549细胞内 NS 基因表达的影响。CCK-8法检测沉默 NS 基因对A549细胞增殖的影响，流式细胞术检测对细胞周期的影响，Hoechst33258核染色法和流式细胞术检测对细胞凋亡的影响。结果： Silencer组 NS 基因表达较vector组和normal组明显被抑制（0.166±0.024 vs 0.497±0.022、0.505±0.032, 均 P <0.01）；Silencer组A549细胞增殖活性显著低于vector组和normal组 (0.518±0107 vs 0.855±0.102、0.832±0.158，均 P <0.05)；Silencer组A549细胞周期阻滞于G0/G1期；Silencer组细胞核皱缩呈致密浓染，染色质碎裂呈块状并有边集现象，且细胞凋亡率较vector组与normal组显著增高\[(34.80±6.77)% vs (9.70±150)%, (8.16±2.01)%， P <0.01\]。 结论： RNA干扰沉默 NS 基因可抑制人肺腺癌A549细胞的增殖，促进细胞凋亡。

Objective: To determine the effect of silencing nucleostemin ( NS ) gene expression on proliferation and apoptosis of non-small cell lung cancer (NSCLC) A549 cells in vitro . Methods: The recombinant pcDNA4/C-NS-silencer targeting the NS gene was constructed. Human NSCLS A549 cells were transfected with pcDNA4/C-NS-silencer or the control vectorpcDNA4/C. NS mRNA abundance was assessed by real-time RT-PCR, cell proliferation by CCK-8 assay, and cell cycle progress and apoptosis by flow cytometric assay with Hoechst33258 staining in untransfected and transfected A549 cells. Results: Compared with control vector-transfected and untransfected A549 cells, A549 cells transfected with pcDNA4/C-NS-silencer had significantly lower NS mRNA abundance (0.166±0.024 vs 0.497±0.022, 0.505±0032, P <0.01) and a significantly lower proliferation activity (0.518±0.107 vs 0.855±0.102, 0.832±0.158, P <005). NS gene silencing resulted significant increases in the percentage of cells in G1/G0 phase, in chromatin condensation and fragmentation, and in apoptosis (\[34.80±6.77\]% vs \[9.70±1.50\]%, \[8.16±2.01\]% P <0.01), as compared with control vector-transfected and untransfected A549 cells. Conclusion: RNAi-mediated silencing of the NS gene results in human non-small cell lung cancer cell proliferation, G-1 arrest and apoptosis, thereby possessing a therapeutic potential.

国家自然科学基金资助项目(No. 81372293, No. 81241088)；黑龙江省教育厅科学技术研究项目(No. 12531736)； 黑龙江省卫生厅科研课题(No. 2009-456)