TOP2A在非小细胞肺癌中的高表达促进肿瘤细胞的增殖和侵袭能力

目的:探讨编码拓扑异构酶Ⅱα的基因TOP2A在非小细胞肺癌组织中的表达情况及其生物学功能。方法:采用荧光定量PCR方法检测102例非小细胞肺癌及其癌旁组织中TOP2A的mRNA表达水平，Western blot检测其中5对组织中TOP2A蛋白表达水平，分析TOP2A 表达与非小细胞肺癌主要临床病理特征的相关性。干扰非小细胞肺癌细胞株A549和HCC827中TOP2A的表达，MTT法检测其表达对肿瘤细胞增殖的影响，Transwell法检测TOP2A表达下调对肿瘤细胞侵袭能力的影响。应用流式细胞术检测TOP2A敲降后细胞的凋亡率和细胞周期。结果:TOP2A在非小细胞肺癌组织中的表达水平相较癌旁组织明显上升（P<0.05），干扰TOP2A的表达会抑制非小细胞肺癌细胞的增殖和侵袭。流式细胞凋亡率实验结果显示转染siTOP2A后的非小细胞肺癌细胞早期凋亡率增加；流式周期分析显示siTOP2A转染后的细胞S期发生阻滞抑制细胞增殖。同时，TOP2A表达水平与非小细胞肺癌的肿瘤分期、淋巴结转移密切相关（P<0.05）。结论:TOP2A在非小细胞肺癌中表达上调，与肿瘤增殖和侵袭等生物学行为密切相关。

Overexpression of TOP2A in non -small cell lung cancer promotes cancer cell prolifera-tion and invasion

Objective:To investigate the expression and effects of topoismerase Ⅱ alpha(TOP2A)in non -small cell lung cancer(NSCLC)and the biological function.Methods:The expression level of TOP2A was detected in 102 cases of NSCLC tumor tissues and their corresponding adjacent normal tissues by Real time fluorescent quantitative PCR(qRT -PCR).Western blot assay was used to detect the protein level of TOP2A in five pairs of the tissues a-bove.The relationship between the expression of TOP2A and the NSCLC clinicopathological features was analyzed as well.Interference sequence of TOP2A was designed and transfected into A549 and HCC827 cells.Cell proliferation of A549 and HCC827 was analyzed by MTT.Transwell assay was employed to examine the invasiveness of the transfected cells.The cell apoptotie rate and cell cycle was assayed by flow cytometry.Results:Both mRNA and protein level of TOP2 A in NSCLC tissues was significantly higher than that in their corresponding adjacent normal tissues (P <0.05).Interference of TOP2A inhibited the proliferation and invasion of A5 49 and HCC827 cells.The flow cytom-etry assay revealed that most transfected cells were blocked in S phase ,while cell apoptosis increase(P <0.05). Overexpression of TOP2A in NSCLC tissues was associated with TNMstage and lymph node metastasis(P <0.05).Conclusion:TOP2A was upregulated in NSCLC tissues and promote cell proliferation and invasion.