长链非编码RNA结肠癌相关转录本1(CCAT1)参与将多种癌变为恶性癌症类型。先前研究着重于CCAT1作为miRNAs（微小RNA）的诱饵的功能机制，但与肿瘤转移相关的CCAT1蛋白相互作用的调节机制仍然大部分未知。本研究旨在鉴定CCAT1的全蛋白组配偶，并探索CCAT1蛋白相互作用介导的肿瘤转移。采用RNA反义纯化结合质谱(RAP-MS)方法纯化和识别CCAT1-蛋白质复合物。使用注释、可视化和综合发现数据库和真核生物RNA结合蛋白质数据库(EuRBPDB)网站对CCAT1结合蛋白进行生物信息学分析。采用RNA拉取和RNA免疫共沉淀验证CCAT1-Vimentin相互作用。采用Transwell实验评估HeLa细胞的迁移和侵袭能力。RAP-MS方法通过培养含有核苷酸类似物4-硫尿嘧啶的细胞，并使用365纳米波长紫外线进行交联，效果良好。鉴定了631个蛋白质，其中约60%是EuRBPDB数据库记录的RNA结合蛋白。Vimentin是CCAT1结合蛋白之一，参与了肿瘤转移通路。通过VIM敲低并通过过表达CCAT1进行下调的拯救实验证明，CCAT1可以通过稳定Vimentin蛋白增强肿瘤细胞的迁移和侵袭能力。CCAT1可能与Vimentin蛋白结合并稳定其，从而增强癌细胞的迁移和侵袭能力。Copyright © 2023 The Chinese Medical Association, produced by Wolters Kluwer, Inc. under the CC-BY-NC-ND license.

Long non-coding RNA colon cancer-associated transcript 1 (CCAT1) is involved in transforming multiple cancers into malignant cancer types. Previous studies underlining the mechanisms of the functions of CCAT1 primarily focused on its decoy for miRNAs (micro RNAs). However, the regulatory mechanism of CCAT1-protein interaction associated with tumor metastasis is still largely unknown. The present study aimed to identify proteome-wide CCAT1 partners and explored the CCAT1-protein interaction mediated tumor metastasis.CCAT1-proteins complexes were purified and identified using RNA antisense purification coupled with the mass spectrometry (RAP-MS) method. The database for annotation, visualization, and integrated discovery and database for eukaryotic RNA binding proteins (EuRBPDB) websites were used to bioinformatic analyzing CCAT1 binding proteins. RNA pull-down and RNA immunoprecipitation were used to validate CCAT1-Vimentin interaction. Transwell assay was used to evaluate the migration and invasion abilities of HeLa cells.RAP-MS method worked well by culturing cells with nucleoside analog 4-thiouridine, and cross-linking was performed using 365 nm wavelength ultraviolet. There were 631 proteins identified, out of which about 60% were RNA binding proteins recorded by the EuRBPDB database. Vimentin was one of the CCAT1 binding proteins and was participated in the tumor metastasis pathway. Knocked down VIM and rescued the downregulation by overexpressing CCAT1 demonstrated that CCAT1 could enhance tumor migration and invasion abilities by stabilizing Vimentin protein.CCAT1 may bind with and stabilize Vimentin protein, thus enhancing cancer cell migration and invasion abilities.Copyright © 2023 The Chinese Medical Association, produced by Wolters Kluwer, Inc. under the CC-BY-NC-ND license.