Objective  To investigate the potential role of ALKBH5-mediated m6A modification of Galectin-9 in the invasion, migration, and proliferation of endometrial stromal cells (ESCs) in endometriosis.

Methods  A total of 20 normal endometrial (NC) specimens and 20 ectopic endometrial (EC) specimens from patients with endometriosis were obtained. The expression of ALKBH5 and Galectin-9 in tissues was detected using  immunohistochemistry, qRT-PCR and Western blot. In addition, 10 cases of normal proliferative endometrial tissues were collected and primary ESCs were extracted, and the mechanism of ALKBH5 in regulating the level and mRNA expression of Galectin-9 m6A was investigated by bioinformatics analysis, methylated RNA immunoprecipitation (MeRIP), and RIP assay. After ALKBH5 overexpression, the proliferation, migration, and invasion abilities of ESCs were determined by Transwell and cell counting kit-8 (CCK-8) assays. The effect of ALKBH5 on ESCs invasion, migration, and proliferation was investigated.

Results  Compared with NC tissues, the expression of ALKBH5 and Galectin-9 was increased in EC tissues from patients with endometriosis (P<0.05). ALKBH5 overexpression could reduce the m6A modification level of Galectin-9 and enhance the stability and expression of Galectin-9 mRNA. ALKBH5 overexpression promoted the invasion, migration, and proliferation of ESCs, while Galectin-9 knockdown partially reversed the promoting effect of ALKBH5 overexpression on ESCs invasion, migration, and proliferation (P<0.05).

Conclusion  ALKBH5 promotes ESCs invasion, migration, and proliferation by promoting Galectin-9 mRNA expression via reducing m6A modification.

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