CAFs-derived exosomes promote the development of cervical cancer by regulating miR-18a-5p-TMEM170B signaling axis

Mounting studies have showed that tumor microenvironment (TME) is crucial for cervical cancer (CC), and cancer-related fibroblasts (CAFs) play a major role in it. Recently, exosomal miRNAs secreted by CAFs have been found to be potential targets for cancer diagnosis and therapy. In this paper, we aimed to investigate the function of CAFs-mediated exosome miR-18a-5p (CAFs-exo-miR-18a-5p) in CC. First, in combination with bioinformatic data analysis of the GEO database (GSE86100) and RT-qPCR of CC clinical tissue samples and cell lines, miR-18a-5p was discovered to be markedly up-regulated in CC. Next, CAFs-secreted exosomes were isolated and it was found that miR-18a-5p expression was dramatically promoted in CC cell lines when treated with CAFs-exos. The CAFs-exo-miR-18a-5p was then elucidated to stimulate the proliferation and migration and inhibit the apoptosis of CC cells. In order to clarify the underlying mechanism, we further screened the target genes of miR-18a-5p. TMEM170B was selected by bioinformatic data analysis of online databases combined with RT-qPCR of CC clinical tissues and cells. Luciferase reporter gene analysis combined with molecular biology experiments further elucidated that miR-18a-5p suppressed TMEM170B expression in CC. Finally, both cell and animal experiments demonstrated that TMEM170B over-expression attenuated the oncogenic effect of CAFs-exo-miR-18a-5p. In conclusion, our study indicates that CAFs-mediated exosome miR-18a-5p promotes the initiation and development of CC by suppressing TMEM170B signaling axis, which provides a possible direction for the diagnosis and therapy of CC.