Vav3 在小细胞肺癌组织中的表达及 对细胞迁移和侵袭能力的影响

Effect of Vav3 on cell migration and invasion in small cell lung cancer

摘要:

目的 探讨Vav3 在小细胞肺癌（SCLC）组织中的表达及对细胞迁移和侵袭能力的影响。方法 选 取SCLC 患者87 例及同期因肺外伤行手术治疗的正常肺组织50 例作为对照组，免疫组织化学（免疫组化）检 测SCLC 和对照组组织中Vav3 蛋白的表达，培养人小细胞肺癌H446 细胞并分为siRNA-Vav3 组、siRNA- 对 照序列组和空白组，实时荧光定量PCR 技术检测各组细胞中Vav 3 基因表达，划痕实验检测各组细胞迁移能 力，Transwell 法检测各组细胞迁移和侵袭能力。结果 SCLC 组织中Vav3 蛋白阳性表达率为81.6%，高于对照 组的14.0%（χ2=17.739，P =0.000）；SCLC 组织中Vav3 蛋白表达与临床分期、远处转移和生存状态有关（P = 0.024、0.016 和0.014）；Vav3 蛋白阳性表达组患者平均生存时间23.14 个月，而阴性表达组则为44.89 个月，差 异有统计学意义（χ2=6.280，P =0.012）；siRNA-Vav3 组细胞中Vav3 mRNA 相对表达量低于siRNA- 对照序列 组和空白组（P=0.000）；siRNA-Vav3 组细胞24 h 后划痕愈合率低于siRNA- 对照序列组和空白组，siRNAVav3 组迁移细胞数低于siRNA- 对照序列组和空白组（P =0.000）；siRNA-Vav3 组侵袭细胞数低于siRNA- 对 照序列组和空白组（P =0.000）。结论 Vav3 蛋白在SCLC 组织中呈高表达，且与患者预后相关，特异性沉默 SCLC 细胞中Vav3 基因可抑制细胞迁移和侵袭能力。

Abstract:

Objective To investigate the expression of Vav3 in small cell lung cancer (SCLC) and its effect on cell migration and invasion. Methods Totally 87 cases of SCLC and 50 cases of normal lung tissues were involved. Expressions of Vav3 proteins in lung tissue were measured by immunohistochemistry. Human small cell lung cancer cell line H446 were divided into siRNA-Vav3 group, siRNA-vehicle group and blank group. Real-time fluorescence quantitative PCR was utilized to detect Vav3 gene expression. Cellular migration and invasioncapability were determined by scratching assay and Transwell assay, respectively. Results Positive rate of Vav3 protein in SCLC tissues was increased significantly compared with control group (81.6% vs 14.0%, χ2 = 17.739, P = 0.000). Expression of Vav3 was positively correlated with clinical stage, distant metastasis and survival rate (P = 0.024, 0.016, and 0.014,respectively). Average survival time (month) in Vav3 positively expressed group was shortened dramatically when compared with that in Vav3 negatively expressed group (23.14 vs 44.89, χ2 = 6.280, P = 0.012). PCR results suggested that siRNA-Vav3 knocked down Vav3 expression compared with siRNA-vehicle group and blank group (P = 0.000). Cells in siRNA-Vav3 group experienced obviously decreased healing rate and migration capability compared with siRNA-control sequence group and blank group (P = 0.000). Conclusion Silencing of Vav3 inhibits cell migration and invasion ability and is potentially a prognostic biomarker for SCLC.