Abstract: Objective The aim of this study was to investigate the effects and possible mechanism of arisaema decipiens volatile oil(ADVO)on the malignant biological behavior of thyroid cancer cells. Methods Human thyroid cancer TPC-1 cells were cultured in medium containing different concentrations of ADVO for 48 hours,and the cell viability was detected by CCK-8 method to screen for the optimal concentration.TPC-1 cells were divided into the blank group(conventional culture)and ADVO group(60 μg/mL),miR-762 mimics group(transfected with miR-762 mimics),miR-762 mimics NC group(transfected with miR-762 mimics NC),ADVO+miR-762 mimics group(60 μg/mL+transfected with miR-762 mimics),and ADVO+miR-762 mimics NC group(60 μg/mL+transfected with miR-762 mimics NC).The CCK-8 assay,flow cytometry and Transwell assays were performed in this study.The dual luciferase reporter gene assay was used to verify the targeting relationship between the miR-762 and neurofibromatosis type 2(NF2)gene.The relative expression of miR-762 and NF2 mRNA was detected by RT-qPCR.The expression of merlin,Yes-related protein 1(YAP1),p-YAP1,cleavage cysteine protease-3(C-caspase-3),E-cadherin and vimentin proteins was detected by Western blot. Results The viability of TPC-1 cells decreased with the increase of ADVO concentration(P＜0.05),and the viability of TPC-1 cells at the concentration of 60 μg/mL of ADVO was close to 50%.Compared with the blank group,the cell viability,the expression of miR-762,YAP1 and vimentin protein decreased,the apoptotic rate,the expression of NF2 mRNA and Merlin,p-YAP1,C-caspase-3 and E-cadherin proteins increased,and the number of cell migration and invasion decreased in the ADVO group(P＜0.05).ADVO could weaken the overexpression of miR-762 and inhibit the malignant biological behavior of TPC-1 cells(P＜0.05).According to bioinformatics prediction and the dual luciferase reporter gene assay,NF2 gene might be a potential target gene of miR-762. Conclusion ADVO can inhibit the proliferation,invasion and migration of TPC-1 cells and promote their apoptosis.The mechanism of action may be related to inhibiting the expression of miR-762,increasing the level of Merlin protein encoded by its target gene NF2,and activating related tumor suppressor signals.

Key words: Arisaema decipiens volatile oil, Thyroid cancer, microRNA 762, Neurofibromatosis type 2 gene