RESUMO
BACKGROUND & AIMS: Mucin 13 (MUC13) is reportedly overexpressed in human malignancies. However, the clinicopathological and biological significance of MUC13 in human intrahepatic cholangiocarcinoma (iCCA) remain unclear. The aim of this study was to define the role of MUC13 in the progression of iCCA. METHODS: Expression levels of MUC13 in human iCCA samples were evaluated by immunohistochemistry, western blot, and real-time PCR. In vitro and in vivo experiments were used to assess the effect of MUC13 on iCCA cell growth and metastasis. Crosstalk between MUC13 and EGFR/PI3K/AKT signaling was analyzed by molecular methods. The upstream regulatory effects of MUC13 were evaluated by Luciferase and DNA methylation assays. RESULTS: MUC13 was overexpressed in human iCCA specimens and iCCA cells. MUC13 overexpression positively correlated with clinicopathological characteristics of iCCA, such as vascular invasion and lymph node metastasis, and was independently associated with poor survival. Results from loss-of-function and gain-of-function experiments suggested that knockdown of MUC13 attenuated, while overexpression of MUC13 enhanced, the proliferation, motility, and invasiveness of iCCA cells in vitro and in vivo. Mechanistically, we found that the phosphatidylinositol 3-kinase-AKT signal pathway and its downstream effectors, such as tissue inhibitor of metalloproteinases 1 and matrix metallopeptidase 9, were required for MUC13-mediated tumor metastasis of iCCA. MUC13 interacted with epidermal growth factor receptor (EGFR) and subsequently activated the EGFR/PI3K/AKT signaling pathway by promoting EGFR dimerization and preventing EGFR internalization. We also found that MUC13 was directly regulated by miR-212-3p, whose downregulation was related to aberrant CpG hypermethylation in the promoter area. CONCLUSIONS: These findings suggest that aberrant hypermethylation-induced downregulation of miR-212-3p results in overexpression of MUC13 in iCCA, leading to metastasis via activation of the EGFR/PI3K/AKT signaling pathway. LAY SUMMARY: Mucin 13 overexpression has been implicated in the development of malignancies, although its role in intrahepatic cholangiocarcinoma has not been studied. Herein, we show that mucin 13 plays a critical role in intrahepatic cholangiocarcinoma. Mucin 13 could have therapeutic value both as a prognostic marker and as a treatment target.
Assuntos
Neoplasias dos Ductos Biliares/metabolismo , Colangiocarcinoma/metabolismo , Progressão da Doença , Mucinas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/genética , Animais , Neoplasias dos Ductos Biliares/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Colangiocarcinoma/patologia , Receptores ErbB/metabolismo , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Mucinas/genética , Estudos Retrospectivos , Transfecção , Carga Tumoral/genética , Regulação para Cima , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND@#TRIM proteins are important members of E3 ubiquitin ligases, and many studies have confirmed that TRIM family members play an important role in the development of various tumors. We found that TRIM59 expression level in non-small cell lung cancer (NSCLC) was significantly increased through second-generation sequencing. The purpose of this study was to investigate the expression of TRIM59 in NSCLC and its relationship with the clinicopathological parameters as well as the prognosis of patients.@*METHODS@#The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets were excavated to analyze the expression of TRIM59 mRNA in NSCLC and its relationship with the prognosis of patients; The expression of TRIM59 protein in 90 tumor tissues and adjacent tissues was detected by immunohistochemical staining, and the relationship between the expression of TRIM59 protein and clinicopathological parameters and prognosis was analyzed.@*RESULTS@#Overexpression of TRIM59 mRNA in tumor tissues predicted poor prognosis. The expression level of TRIM59 protein was significantly higher in tumor tissues than in adjacent tissues, and TRIM59 protein expression was correlated with tumor size (P=0.007), tumor differentiation (P=0.009), tumor-node-metastasis (TNM) stage (P=0.003) and lymph node metastasis (P=0.003). Multivariate Cox regression analyses showed that along with TNM stage, overexpression of TRIM59 could be considered an independent prognostic factor for NSCLC patients.@*CONCLUSIONS@#The expression of TRIM59 is closely related to the prognosis of NSCLC patients, and it is an independent risk factor for NSCLC patients.
