Abstract：
Tongue squamous cell carcinoma (TSCC) is prevailing malignancy in the oral and maxillofacial region, characterized by its high frequency. LncRNA CCAT1 can promote tumorigenesis and progression in many cancers. Here, we investigated the regulatory mechanism by which CCAT1 influences growth and metastasis of TSCC. Levels of CCAT1, WTAP, TRIM46, PHLPP2, AKT, p-AKT, and Ki67 in TSCC tissues and cells were assessed utilizing qRT-PCR, Western blot and IHC. Cell proliferation, migration, and invasion were evaluated utilizing CCK8, colony formation, wound healing and transwell assays. Subcellular localization of CCAT1 was detected utilizing FISH assay. m6A level of CCAT1 was assessed using MeRIP. RNA immunoprecipitation (RIP), Co-immunoprecipitation (Co-IP) and RNA pull down elucidated binding relationship between molecules. Nude mouse tumorigenesis experiments were used to verify the TSCC regulatory function of CCAT1 in vivo. Metastatic pulmonary nodules were observed utilizing hematoxylin and eosin (HE) staining. CCAT1 silencing repressed TSCC cell proliferation, migration and invasion. Expression of CCAT1 was enhanced through N6-methyladenosine (m6A) modification of its RNA, facilitated by WTAP. Moreover, IGF2BP1 up-regulated CCAT1 expression by stabilizing its RNA transcript. CCAT1 bond to PHLPP2, inducing its ubiquitination and activating AKT signaling. CCAT1 mediated the ubiquitination and degradation of PHLPP2 by TRIM46, thereby promoting TSCC growth and metastasis. CCAT1/TRIM46/PHLPP2 axis regulated proliferation and invasion of TSCC cells, implying that CCAT1 would be a novel therapeutic target for TSCC patients.
摘要：
舌鳞状细胞癌（TSCC）是口腔颌面部常见的恶性肿瘤，其特点是频率高。LncRNACCAT1可以促进许多癌症的肿瘤发生和进展。这里,我们研究了CCAT1影响TSCC生长和转移的调控机制。CCAT1、WTAP、TRIM46,PHLPP2,AKT,p-AKT,并利用qRT-PCR评估TSCC组织和细胞中的Ki67，Westernblot和IHC。细胞增殖，迁移,利用CCK8，菌落形成，伤口愈合和transwell分析。利用FISH测定法检测CCAT1的亚细胞定位。使用MeRIP评估CCAT1的m6A水平。RNA免疫沉淀(RIP),免疫共沉淀(Co-IP)和RNA下拉阐明了分子之间的结合关系。使用裸鼠肿瘤发生实验来验证CCAT1在体内的TSCC调节功能。使用苏木精和伊红（HE）染色观察转移性肺结节。CCAT1沉默抑制TSCC细胞增殖，移民和入侵。通过N6-甲基腺苷(m6A)修饰其RNA增强CCAT1的表达,由WTAP促成。此外，IGF2BP1通过稳定其RNA转录物上调CCAT1表达。CCAT1与PHLPP2结合，诱导其泛素化并激活AKT信号传导。CCAT1通过TRIM46介导PHLPP2的泛素化和降解，从而促进TSCC的生长和转移。CCAT1/TRIM46/PHLPP2轴调节TSCC细胞的增殖和侵袭，这意味着CCAT1将成为TSCC患者的新治疗靶点。
