TFAP2E methylation promotes 5 ‑fluorouracil resistance via exosomal miR‑106a‑5p and miR‑421 in gastric cancer MGC‑803 cells.

TFAP2E methylation promotes 5‑fluorouracil resistance via exosomal miR‑106a‑5p and miR‑421 in gastric cancer MGC‑803 cells. Mol Med Rep. 2019 May 14;: Authors: Jingyue S, Xiao W, Juanmin Z, Wei L, Daoming L, Hong X Abstract Hypermethylation of transcription factor activating enhancer‑binding protein 2e (TFAP2E) has been reported to be associated with chemoresistance to 5‑fluorouracil (5‑FU) in gastric cancer (GC). In the present study, the molecular mechanism governing this chemoresistance was investigated. Drug‑resistant human GC MGC‑803/5‑FU cells were established and TFAP2E expression and methylation levels were assessed. Autocrine exosomes from GC culture medium were isolated and characterized. MicroRNA (miRNA) microarray analysis was used to determine the miRNA expression profile of GC cell‑derived exosomes. Exosomes collected from MGC‑803/5‑FU cells were co‑cultured with control cells, and 5‑Aza‑2'‑deoxycytidine (5Aza) was added into MGC‑803/5‑FU cells to investigate the relationship between TFAP2E, exosomes and chemosensitivity. In the present study, it was demonstrated that hypermethylation of TFAP2E resulted in its reduced expression and 5‑FU chemoresistance in GC cells. miRNAs miR‑106a‑5p and miR‑421 were highly expressed and regulated the chemoresistance induced by TFAP2E methylation. Target gene prediction using miRBase, TargetScan and PicTar revealed that E2F1, MTOR and STA...
Source: Molecular Medicine Reports - Category: Molecular Biology Tags: Mol Med Rep Source Type: research