Dicer 在胃癌中的表达意义及对细胞生长和迁移的影响

目的：探究 Dicer 在胃癌中的表达情况、与临床病理参数的相关性及对细胞生长和迁移的作用。方法：收集56例胃癌患者的癌组织样本和癌旁组织样本，利用实时定量 PCR 的方法检测 Dicer 在这些样本中的表达情况。选用2株人胃癌细胞系 AGS 和 MGC803，RNAi 技术干扰下调 Dicer 的表达，CCK －8法分析 Dicer表达下调对胃癌细胞生长情况的影响，迁移小室实验分析 Dicer 表达下调对胃癌细胞体外迁移能力的影响。结果：56例胃癌患者中，14例（25．0％）患者 Dicer 表达水平升高，27例（48．2％）患者表达降低，15例（26．8％）患者表达无明显变化；Dicer mRNA 的表达降低与胃癌患者淋巴结转移和 TNM分期存在关联，而与患者性别、年龄、肿瘤大小及癌细胞分化程度无关。沉默 Dicer 表达后，两株胃癌细胞的生长和迁移能力显著升高。结论：Dicer 在胃癌组织中表达降低，且与患者淋巴结转移和 TNM分期相关，其低表达有利于胃癌细胞的恶性生长和侵袭转移。

Clinical significance of Dicer expression in gastric cancer and functional study on cell growth and migration

Objective:To study the expression and clinical relevance of Dicer in gastric cancer and its roles on cell growth and migration.Methods:A total of 56 pairs of cancer samples and adjacent non -tumor tissues were obtained from gastric cancer patients undergoing primary surgical resection and quantitative RT -PCR was employed to detect the expression of Dicer at mRNA level.Two human gastric cancer cell lines were transfected with small interference RNA against Dicer and examined by qRT -PCR,Western Blot to determine the mRNA and protein level of Dicer.CCK -8 assays were then performed to investigate the effects of Dicer on gastric cancer cell proliferation,Transwell assays were performed to investigate the effects of Dicer on gastric cancer cell migration.Results:Among the 56 pairs of clinical samples,14 /56(25.0%)displayed at least a 1.5 -fold increase,27 /56(48.2%)exhibited an over 1.5-fold decrease and 15 /56 (26.8%)showed no significant change.The mRNA level of Dicer was correlated with lymph node metastasis and TNMstage of patients and was not statistically correlated with the gender,age,tumor size or other clinicopathological characteristics.Functional studies revealed that knocking down Dicer in AGS and MGC803 cells promoted cell growth and migration.Conclusion:Dicer is frequently downregulated in gastric cancer and this downregulation is closely related to lymph node metastasis and TNMstage of patients.Dicer knockdown could promote the growth and migration of gastric cancer cells in vitro.