Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital of Soochow University, Suzhou, 215006, China.
Institute of Respiratory Diseases, Soochow University, Suzhou, 215006, China.
Cell Commun Signal. 2022 Jan 31;20(1):16. doi: 10.1186/s12964-021-00818-8.
Non-small cell lung cancer (NSCLC) is the most common type of lung cancer and the most lethal tumour worldwide. Copine 1 (CPNE1) was identified as a novel oncogene in NSCLC in our previous study. However, its specific function and relative mechanisms remain poorly understood.
The biological role of CPNE1 and RACK1 in NSCLC was investigated using gene expression knockdown and overexpression, cell proliferation assays, clonogenic assays, and Transwell assays. The expression levels of CPNE1, RACK1 and other proteins were determined by western blot analysis. The relationship between CPNE1 and RACK1 was predicted and investigated by mass spectrometry analysis, immunofluorescence staining, and coimmunoprecipitation. NSCLC cells were treated with a combination of a MET inhibitor and gefitinib in vitro and in vivo.
We found that CPNE1 facilitates tumorigenesis in NSCLC by interacting with RACK1, which further induces activation of MET signaling. CPNE1 overexpression promoted cell proliferation, migration, invasion and MET signaling in NSCLC cells, whereas CPNE1 knockdown produced the opposite effects. In addition, the suppression of the enhancing effect of CPNE1 overexpression on tumorigenesis and MET signaling by knockdown of RACK1 was verified. Moreover, compared to single-agent treatment, dual blockade of MET and EGFR resulted in enhanced reductions in the tumour volume and downstream signaling in vivo.
Our findings show that CPNE1 promotes tumorigenesis by interacting with RACK1 and activating MET signaling. The combination of a MET inhibitor with an EGFR-TKI attenuated tumour growth more significantly than either single-drug treatment. These findings may provide new insights into the biological function of CPNE1 and the development of novel therapeutic strategies for NSCLC. Video Abstract.
非小细胞肺癌（NSCLC）是最常见的肺癌类型，也是全球最致命的肿瘤。在我们之前的研究中，CPNE1 被鉴定为 NSCLC 的一种新的癌基因。然而，其具体功能和相关机制仍知之甚少。
采用基因表达敲低和过表达、细胞增殖实验、集落形成实验和 Transwell 实验研究 CPNE1 和 RACK1 在 NSCLC 中的生物学作用。通过 Western blot 分析测定 CPNE1、RACK1 和其他蛋白的表达水平。通过质谱分析、免疫荧光染色和免疫共沉淀预测和研究 CPNE1 与 RACK1 的关系。在体外和体内用 MET 抑制剂和吉非替尼联合处理 NSCLC 细胞。
我们发现 CPNE1 通过与 RACK1 相互作用促进 NSCLC 肿瘤发生，进而诱导 MET 信号的激活。CPNE1 过表达促进 NSCLC 细胞的增殖、迁移、侵袭和 MET 信号，而 CPNE1 敲低则产生相反的效果。此外，通过敲低 RACK1 验证了 CPNE1 过表达对肿瘤发生和 MET 信号增强作用的抑制。此外，与单药治疗相比，MET 和 EGFR 的双重阻断在体内导致肿瘤体积和下游信号的减少更为显著。
我们的研究结果表明，CPNE1 通过与 RACK1 相互作用促进肿瘤发生，并激活 MET 信号。MET 抑制剂与 EGFR-TKI 的联合使用比单一药物治疗更能显著抑制肿瘤生长。这些发现可能为 CPNE1 的生物学功能提供新的见解，并为 NSCLC 的新治疗策略的发展提供新的思路。
