THE EFFECT OF DEXMEDETOMIDINE ON BREAST CANCER CELL GROWTH AND METASTASIS BY REGULATING THE EXPRESSION OF CIRCRNA AND ITS EFFECT MECHANISM

Mingxin Ji, Peng Zhao, Yunfeng Cui, Xinyu Li^*

Department of Anesthesiology, The Second Hospital of Jilin University, Changchun, 130041, China

Objective: The present study aims to study the effect of dexmedetomidine on the growth and metastasis of breast cancer cells by regulating the expression of circular RNA (circRNA) and its mechanism. 

Methods: As many as 25 pairs of freshly frozen breast cancer tissues and adjacent normal tissues were collected from the Second Municipal Affiliated Hospital. Breast adenocarcinoma cells MDA-MB-231 were purchased from the American Type Culture Collection. According to the purpose of the experiment, the obtained tissue samples were divided into healthy control group (normal tissue) and observation group (breast cancer tissue). According to cultured cells, they were divided into: MDA-MB-231 group (cells cultured under normal conditions) and dexmedetomidine treatment group (1µM dexmedetomidine cultured cells). The researchers obtained the informed consent from each patient, and the study was approved by the ethics committee of the First Hospital. The expression of circRNA in the tissue samples and cell lines of the different treatment groups was analyzed by RT-PCR. The cell proliferation of the two groups was determined by MTT following 24h, 48h and 72h. Transwell migration was carried out to detect cell invasion and migration. CCK-8 was used to detect cell viability. The protein expression of α2-ADR and STAT3 in the cells was analyzed by Western blot. 

Results: The mRNA expression of circPGAP3, circANKS1B and circTHSD4 in the observation group was higher than that of the healthy group (P<0.05), and the mRNA expression of circ CYP24A1 in the observation group was lower than that in the healthy group (P<0.05). The mRNA expression of circPGAP3, circANKS1B and circTHSD4 in the dexmedetomidine group was higher than that of the MDA-MB-231 group (P<0.05), and the mRNA expression of circ CYP24A1 in the dexmedetomidine group was lower than that of the MDA-MB-231 group (P<0.05). The absorbance value of the dexmedetomidine treatment group was higher than that of the MDA-MB-231 group following 24h and 48h (P<0.05), and the absorbance value of the dexmedetomidine treatment group was higher than that of the MDA-MB-231 group following 72h (P<0.05). The number of cell invasion and cell migration in the dexmedetomidine treatment group was higher than that of the MDA-MB-231 group (P<0.05). The apoptosis rate of the dexmedetomidine treatment group was lower than that of the MDA-MB-231 group (P<0.05), and the cell viability of the dexmedetomidine treatment group was higher than that of the MDA-MB-231 group (P<0.05). The protein expression of α2-ADR and STAT3 in the dexmedetomidine treatment group was higher than that of the MDA-MB-231 group (P<0.05). 

Conclusion: dexmedetomidine promoted the growth and migration of breast cancer cells by regulating the expression of circRNA.