Background The Ecotropic viral integration site 5 (Evi5) is recognized as a potential oncogene and a cell cycle regulator. Evi5 regulates the abundance of Emi1, an inhibitor of the anaphase-promoting complex/cyclosome, to govern mitotic fidelity. Evi5 has been shown to be dysregulated in several cancer types. However, the expression and biological function of Evi5 in human laryngeal squamous cell carcinoma (LSCC) are still unknown. Methods Clustered regularly interspaced short palindromic repeats (CRISPR)-based gene editing was used to generate Evi5 knockout (KO) LSCC cells. The proliferation and cell cycle distribution of LSCC cells was determined. The effect of Evi5 on LSCC tumor growth in vivo was studied in a tumor xenograft model in mice. The interaction between Evi5 and c-Myc was detected by immunoprecipitation (IP) assay. Luciferase assay was used to determine the transcriptional activity of c-Myc. Results Here, we show that Evi5 controls LSCC tumorigenesis via the stabilization of c-MYC oncogene. CRISPR-mediated knockout (KO) of Evi5 decreased the proliferation and decreased colony formation ability of LSCC cells. Knockout of Evi5 caused increased G1 phase and decreased S phase cells. In the tumor-bearing nude mice, The transplanted tumors originated from Evi5-KO TU212 cells were significantly decreased when compared with control TU212 cells. At the molecular level, we found that Evi5 interacted with c-MYC and Evi5 antagonized E3 ligase FBXW7-mediated ubiquitination and degradation of c-Myc protein, and promoted c-Myc-dependent transactivation. Conclusion Given the critical role of c-Myc in tumorigenesis, our data suggest that Evi5 is a potential therapeutic target in LSCC, and inhibition of Evi5 should be a prospective strategy for LSCC therapy.

中文翻译：

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Evi5癌基因通过稳定c-Myc蛋白促进喉癌细胞增殖。

背景 Ecotropic 病毒整合位点 5 (Evi5) 被认为是潜在的致癌基因和细胞周期调节剂。Evi5 调节 Emi1 的丰度，Emi1 是后期促进复合物/环体的抑制剂，以控制有丝分裂的保真度。Evi5 已被证明在几种癌症类型中失调。然而，Evi5在人喉鳞状细胞癌（LSCC）中的表达和生物学功能仍然未知。方法 使用基于聚集规则间隔短回文重复 (CRISPR) 的基因编辑来生成 Evi5 敲除 (KO) LSCC 细胞。测定了LSCC细胞的增殖和细胞周期分布。在小鼠的肿瘤异种移植模型中研究了 Evi5 对体内 LSCC 肿瘤生长的影响。通过免疫沉淀 (IP) 测定法检测 Evi5 和 c-Myc 之间的相互作用。荧光素酶测定用于确定 c-Myc 的转录活性。结果 在这里，我们表明 Evi5 通过稳定 c-MYC 癌基因来控制 LSCC 肿瘤发生。CRISPR 介导的 Evi5 敲除 (KO) 降低了 LSCC 细胞的增殖和集落形成能力。敲除 Evi5 导致 G1 期细胞增加和 S 期细胞减少。在荷瘤裸鼠中，与对照 TU212 细胞相比，源自 Evi5-KO TU212 细胞的移植肿瘤显着减少。在分子水平上，我们发现Evi5与c-MYC相互作用，Evi5拮抗E3连接酶FBXW7介导的c-Myc蛋白泛素化和降解，促进c-Myc依赖性反式激活。结论 鉴于 c-Myc 在肿瘤发生中的关键作用，