LncRNA MT1JP acts as a tumor inhibitor via reciprocally regulating Wnt/β-Catenin pathway in retinoblastoma

OBJECTIVE: The aim of this study was to investigate the roles of MT1JP and beta-catenin in retinoblastoma. PATIENTS AND METHODS: We performed quantitative Reverse Transcriptase-Polymerase Chain Reaction (qRT-PCR) to quantify the expressions of MT1JP and beta-catenin in 44 retinoblastoma tissues and matched non-tumor tissues. What's more. retinoblastoma cell lines were transfected with pcDNA3.1-MT1JP, after which proliferation, cell cycle, apoptosis, and expression of beta-catenin as well as its downstream targets were assayed. We also conducted TOP-Flash reporter assay to explore the activity of Wnt/beta-catenin signaling pathway. RESULTS: The results revealed that MT1JP was down-regulated, while beta-catenin was highly expressed in retinoblastoma cells. Meanwhile, the forced expression of MT1JP impaired the expression of the beta-catenin protein and its downstream targets such as cyclin D1. c-myc. CONCLUSIONS: We demonstrated that MT1JP was a tumor suppressor by negatively modulating the activity of the Wnt/beta-catenin signaling pathway in the development of retinoblastoma and might function as a prognostic biomarker and therapeutic target.