BACKGROUND The oncogene IQ motif-containing GTPase activating protein 3 (IQGAP3) is ubiquitously overexpressed in several human cancers. This study was designed to explore the expression and role of IQGAP3 in colorectal cancer. METHODS We first assessed the IQGAP3 expression level in colorectal cancer. The correlation of IQGAP3 expression with the clinicopathological characteristics and prognosis was then assessed. At last, we investigated the function of IQGAP3 in colorectal cancer by knocking down its expression in colorectal cancer cell lines. RESULTS Consistent with the conclusions drawn from The Cancer Genome Atlas database, IQGAP3 was upregulated in colorectal cancer at the tissue level and cellular level. Based on immunohistochemistry results of the tissue microarrays, we demonstrated that higher expression of IQGAP3 was associated with higher tumor node metastasis stage (P = 0.005), higher incidence of lymph node metastasis (P = 0.004), and shorter overall survival (P = 0.022). Knockdown of IQGAP3 in colorectal cancer cell lines remarkably decreased their proliferation and migration abilities. CONCLUSION Our data provide evidence that IQGAP3 significantly promote malignant progression of colorectal cancer and could serve as a potential therapeutic target.

中文翻译：

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IQGAP3 的高表达表明结直肠癌患者预后不良。

背景 含有致癌基因 IQ 基序的 GTP 酶激活蛋白 3 (IQGAP3) 在几种人类癌症中普遍过度表达。本研究旨在探讨 IQGAP3 在结直肠癌中的表达和作用。方法 我们首先评估了结直肠癌中 IQGAP3 的表达水平。然后评估IQGAP3表达与临床病理学特征和预后的相关性。最后，我们通过降低 IQGAP3 在结直肠癌细胞系中的表达来研究 IQGAP3 在结直肠癌中的功能。结果 与癌症基因组图谱数据库得出的结论一致，IQGAP3 在结直肠癌中的组织水平和细胞水平上调。基于组织微阵列的免疫组化结果，我们证明 IQGAP3 的较高表达与较高的肿瘤淋巴结转移阶段（P = 0.005）、较高的淋巴结转移发生率（P = 0.004）和较短的总生存期（P = 0.022）相关。在结肠直肠癌细胞系中敲低 IQGAP3 显着降低了它们的增殖和迁移能力。结论 我们的数据提供证据表明 IQGAP3 显着促进结直肠癌的恶性进展，并可作为潜在的治疗靶点。