Aldehyde dehydrogenase 1, a target of miR-222, is expressed at elevated levels in cervical cancer.

The aim of the present study was to investigate the expression of microRNA-222 (miR-222) and aldehyde dehydrogenase 1 (ALDH1) in tissues and peripheral blood of cervical cancer patients, and to elucidate their underlying mechanisms of action. Tumor tissues and tumor-adjacent tissues were obtained from 33 cervical cancer patients and peripheral blood was obtained from these patients and 28 healthy subjects. The expression of miR-222 and ALDH1 mRNA was evaluated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). To examine the levels of ALDH1 protein in tissues and blood, western blotting and ELISA were used. To confirm a direct interaction between miR-222 and ALDH1 mRNA, a dual luciferase reporter assay was performed. HeLA cells were transfected with agomiR-222 and expression of ALDH1 in the cells was measured by RT-qPCR and western blotting. MTT assay was preform to investigate the proliferation of HeLA cells. Expression of ALDH1 mRNA and protein was elevated in cervical cancer tissues and peripheral blood from patients compared with tumor-adjacent tissues and healthy controls, while the expression of miR-222 was reduced. Upregulation of miR-222 inhibited HeLA cell proliferation possibly due to a reduction in the expression of ALDH1. A dual luciferase reporter assay showed that miR-222 can bind with the 3'-untranslated seed region of ALDH1 mRNA to regulate its expression. miR-222 regulation of ALDH1 expression may play a role in the prevention of cervical cancer.