PLK1在套细胞淋巴瘤中的表达及临床意义

PLK1 Expression in Mantle Cell Lymphoma and Its Clinical Significance

目的:研究PLK1在套细胞淋巴瘤中的表达,探讨shRNA干扰沉默PLK1基因表达对套细胞淋巴瘤Jeko-1细胞增殖、凋亡、周期的影响。方法:应用免疫组织化学S-P法检测42例套细胞淋巴瘤和30例反应性增生淋巴结炎患者组织中PLK1蛋白并进行分析与比较。PLK1 shRNA慢病毒感染Jeko-1细胞,应用RQ-PCR检测PLK1 mRNA的表达及Western blot检测PLK1蛋白的表达,鉴定PLK1 shRNA干扰沉默效果,CCK-8试验检测细胞增殖,AnnexinⅤ/PI双染检测细胞凋亡, PI单染检测细胞周期,Western blot测定凋亡相关蛋白BAX BCL-2、Caspase-3的变化。结果:套细胞淋巴瘤患者组织中PLK1阳性率66.67%(28/42),明显高于增生淋巴结炎患者组织的20%(6/30)(P <0.05)。PLK1阳性表达与套细胞淋巴瘤患者B症状、IPI评分、Ann-Arbor临床分期存在相关性(P <0.05)。PLK1 shRNA慢病毒感染Jeko-1细胞72 h后,PLK1 mRNA和PLK1蛋白表达明显下降(P<0.05),PLK1 shRNA组细胞增殖率明显低于对照和Neg shRNA组(P <0.05),PLK1 shRNA组细胞的凋亡率为(27.42±3.44)%,明显高于对照组的(1.23±0.42)%和Neg shRNA组的(2.07±0.58)%(P <0.05)。细胞周期分析发现,PLK1 shRNA组的G2/M期细胞比例为(27.21±3.59)%,高于对照组的(13.28±2.63)%及Neg shRNA组的(14.34±2.37)%(P <0.05)。凋亡相关蛋白检测显示,促凋亡蛋白BAX上调,抑制凋亡蛋白BCL-2表达下调、caspase-3表达上调。结论:PLKl在套细胞淋巴瘤患者组织中过量表达,干扰沉默PLK1基因可抑制人套细胞淋巴瘤Jeko-1细胞细胞增殖,诱导细胞凋亡,阻滞细胞周期于G2/M期。

Objective:To explore the expression level of PLK1 in mantle cell lymphoma(MCL),and the effect of silencing PLK1 gene by RNA interference on the cell proliferation,apoptosis,and cell cycle.Methods:S-P immunohistochemistry technique was used to detect the expression of PLK1 in tissues of 42 patients with MCL and 30 patients with reactive proliferative lymphodenitis(RPL),their expression levels were compared and analyzed.The Jeko-1 cells were transfected with lentivirus contaiming PLK-1 shRNA,then the mRNA and protein expression of PLK-1 was detected by real-time guantitative PCR and Western blot nespectively,and the silencing efficacy of PLK-1 shRNA was identificd.The cell proliferation was detected by CCK method,the cell apoptosis was detected by Annexin V/PI double staining,the cell cycle was detected by PI single staining,the changes of apoptosis-related proteins BAX,BCL-2 and Caspase 3 were detected by Western blot.Results:The positive expression rate of PLK-1 in tissue of MCL patients was66.67%(28/42),which was significanfly higher than 20%(6/30)in tissue of RPL patients(P<0.05).The PLK-1 positive expression correlated with B symptom,IPI score,Ann-Arbor stage(P<0.05).After infection of Jeko-1 cells with lentivirus containing PLK-1 shRNA for 72 hours,the mRNA and protein expressions of PLK-1 were significantly downregulated(P<0.05),the proliferation rate of cells in group of PLK-1 shRNA was significanly lower than that in control and Neg shRNA groups(P<0.05);the apoptosis rate of cells in PLK-1 shRNA group was(27.42±3.44)%,which was significantly higher than that in control group(1.23±0.42)%and Neg shRNA group(2.07±0.58)%(P<0.05).The cell cycle analysis showed that the cell ratio in G2/M phase of PLK-1 shRNA group was(27.21±3.59)%,which was higher than that in control group(13.28±2.63)%and Neg shRNA group(14.34±2.37)%.The detection of apoptosis-related proteins showed that the expression of BAX was up-regulated,the expression of BCL-2 was down-regnlated and the expression of caspase 3 was up-regulated.Conclusion:The PLK-l overexpression appears in tissue of MCL patients.The silencing PLK-1 gene can inhibit the proliferation of Jeko-1 cells,induce the apopotosis of Jeko-1 cells and arrestes cell cycle in G2/M phase.