METTL3-mediated NFAT5 Upregulation Promotes Cervical Cancer Progression Through Enhancing the Mitochondrial Function by Transcriptional Regulation of PRDX1

Abstract

Nuclear factor of activated T-cells 5 (NFAT5) is recognized as an oncogene in a variety of tumors. However, the role of NFAT5 in cervical cancer (CC) cell phenotypic alterations remains to be elucidated. Here, we demonstrated that NFAT5 expression was elevated in CC samples and cells using quantitative real-time reverse transcription PCR, Western blot analysis, and immunohistochemistry assays, and high NFAT5 expression showed a poor prognosis. After C-33A cells were transfected with pcDNA-NFAT5 or NFAT5-short hairpin RNA (shRNA), cell proliferation, invasion, and apoptosis were evaluated using CCK-8 and EdU assays, transwell assays, and flow cytometry, respectively. Biomarkers indicating mitochondrial function, including the expression of the d-loop, ATP levels, and mitochondrial membrane potential, were detected. NFAT5 knockdown restrained cell proliferation and invasion, impaired mitochondrial function, and increased the ratio of cell apoptosis; however, NFAT5 overexpression showed the opposite results. RNA immunoprecipitation (RIP) and methylated RIP (MeRIP) assays were performed to identify interactions among NFAT5, methyltransferase-like 3 (METTL3), and insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3). Chromatin immunoprecipitation and dual-luciferase reporter gene assays demonstrated that NFAT5 binds to the peroxiredoxin 1 (PRDX1) promoter to drive PRDX1 transcription. METTL3 enhanced NFAT5 mRNA stability through IGF2BP3-mediated N6-Methyladenosine (m⁶A) modification, and NFAT5 transcriptionally regulated PRDX1 expression. Moreover, the reintroduction of METTL3 or PRDX1 promoted cell growth and mitochondrial function damage in NFAT5-silenced cells. In vivo experiments further demonstrated that NFAT5 promotes CC tumor growth. Taken together, NFAT5 upregulation mediated by the METTL3/IGF2BP3 complex in an m⁶A-dependent manner facilitates CC cell growth by transcriptionally regulating PRDX1 expression, providing a novel target for CC therapy.