RNA-binding protein MEX3D promotes cervical carcinoma tumorigenesis by destabilizing TSC22D1 mRNA

Abstract

RNA-binding proteins (RBPs) have been related to cancer development. Their functions in cervical cancer, however, are virtually unknown. One of these proteins, Mex-3 RNA-binding family member D (MEX3D), has been recently found to exhibit oncogenic properties in a variety of cancer types. In this present study, the functional roles and the regulatory mechanisms underlying MEX3D were examined in cervical cancer. The detection of MEX3D mRNA expression levels in cervical tissues was performed using reverse transcription-quantitative PCR. For functional analysis, for detecting apoptosis and cell proliferation in cervical cancer cells, the Cell Counting Kit-8, colony formation, and flow cytometry were utilized (SiHa and CaSki). The potential mechanisms of MEX3D were assessed and elucidated utilizing western blot analysis, RNA pull-down, RNA immunoprecipitation, and mRNA stability assays. For verification of MEX3D role in vivo, mouse xenograft models were established. When compared to normal cervical tissues, MEX3D expression was observed to be higher in cervical cancer tissues. MEX3D expression was increased in human papillomavirus (HPV) 16 positive cervical cancer tissues and positively regulated by HPV16 E7. When MEX3D expression was knocked down in cervical cancer cells, cell proliferation was decreased, colony formation was inhibited, and apoptosis was promoted. Furthermore, in a mouse xenograft model, knocking down MEX3D expression reduced cervical cancer tumor growth. In addition, MEX3D acted as an RBP to reduce TSC22 domain family protein 1 (TSC22D1) mRNA stability by directly binding to TSC22D1 mRNA. The findings revealed that MEX3D is upregulated by HPV16 E7 and has a crucial oncogenic in cervical cancer development via sponging TSC22D1 for destabilizing its mRNA levels. According to the findings of this study, MEX3D may be a potential therapeutic target for treating cervical cancer patients.