miR-135a acts as a tumor suppressor by targeting ASPH in endometrial cancer.

: Endometrial cancer (EC) ranks as the fourth most commonly diagnosed cancer type in women worldwide. MicroRNAs (miRNAs) are important regulators with crucial roles in regulating diverse biologic processes, including tumor initiation and progression. Previous studies have demonstrated that miR-135a was correlated with tumorigenesis in various cancers. However, its expression and biologic role in EC remained to be determined. This study aimed to clarify whether miR-135a acts as a tumor suppressor in EC by regulating the expression of aspartate-β-hydroxylase (ASPH). Expression of miR-135a was measured by qRT-PCR and the results demonstrated that miR-135a was downregulated in EC cell lines compared to a normal cell line. Cell counting kit-8 (CCK-8) and wound-healing assays demonstrated that overexpression of miR-135a significantly inhibited cell proliferation and migration. Online prediction algorithm and dual luciferase activity reporter assay revealed that ASPH acts as a direct target of miR-135a. ASPH expression was downregulated in EC cell lines when miR-135a was overexpressed. Collectively, our results indicate that miR-135a targets ASPH to inhibit EC cell proliferation and migration, suggesting a tumor suppressive role of miR-135a in EC.