Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore , 8 Medical Drive, Singapore 117597, Singapore.
J Proteome Res. 2012 Feb 3;11(2):1433-45. doi: 10.1021/pr2010956. Epub 2012 Jan 10.
Metastasis accounts largely for the high mortality rate of colorectal cancer (CRC) patients. In this study, we performed comparative proteome analysis of primary CRC cell lines HCT-116 and its metastatic derivative E1 using 2-D DIGE. We identified 74 differentially expressed proteins, many of which function in transcription, translation, angiogenesis signal transduction, or cytoskeletal remodeling pathways, which are indispensable cellular processes involved in the metastatic cascade. Among these proteins, stathmin-1 (STMN1) was found to be highly up-regulated in E1 as compared to HCT-116 and was thus selected for further functional studies. Our results showed that perturbations in STMN1 levels resulted in significant changes in cell migration, invasion, adhesion, and colony formation. We further showed that the differential expression of STMN1 correlated with the cells' metastatic potential in other paradigms of CRC models. Using immunohistochemistry, we also showed that STMN1 was highly expressed in colorectal primary tumors and metastatic tissues as compared to the adjacent normal colorectal tissues. Furthermore, we also showed via tissue microarray analyses of 324 CRC tissues and Kaplan-Meier survival plot that CRC patients with higher expression of STMN1 have poorer prognosis.
转移在很大程度上导致结直肠癌（CRC）患者的高死亡率。在这项研究中，我们使用 2-D DIGE 对原发性 CRC 细胞系 HCT-116 和其转移性衍生细胞系 E1 进行了比较蛋白质组分析。我们鉴定出 74 种差异表达的蛋白质，其中许多在转录、翻译、血管生成信号转导或细胞骨架重塑途径中发挥作用，这些途径是参与转移级联的不可或缺的细胞过程。在这些蛋白质中，发现 stathmin-1（STMN1）在 E1 中的表达水平明显高于 HCT-116，因此选择其进行进一步的功能研究。我们的结果表明，STMN1 水平的波动导致细胞迁移、侵袭、黏附和集落形成的显著变化。我们进一步表明，STMN1 的差异表达与 CRC 模型中其他范例中细胞的转移潜能相关。通过免疫组织化学，我们还表明，与相邻的正常结直肠组织相比，STMN1 在结直肠原发肿瘤和转移性组织中高度表达。此外，我们还通过对 324 个 CRC 组织的组织微阵列分析和 Kaplan-Meier 生存图表明，STMN1 表达水平较高的 CRC 患者预后较差。
