OBJECTIVE: To probe into the effect of lidocaine on apoptosis

migration and invasion of bladder cancer cell T24 by up-regulating MDC1-AS and its mechanism. METHODS: Flow cytometry and Transwell experiment were used to analyze the effect of lidocaine（ 1. 25

2. 5 and 5 mg/ml） on apoptosis

migration and invasion of T24 cells. Normal cultured T24 cells were took as the control group. Real-Time quantitative polymerase chain reaction was used to analyze the expression level of mediator of DNA damage checkpoint protein 1 antisense RNA（ MDC1-AS）.The effects of over-expression of MDC1-AS on apoptosis

migration and invasion of T24 cells were analyzed. MDC1-AS over-expression plasmid（ pcDNA-MDC1-AS） and its control（ pcDNA）

MDC1-AS small interfering RNA（ si-MDC1-AS） and its control（ si-NC） were transfected into T24 cells; T24 cells transfected with si-NC and si-MDC1-AS were incubated with the culture medium containing 5 mg/ml lidocaine for 2 h

which were recorded as lidocaine 5 mg/ml +si-NC group and lidocaine 5 mg/ml + si-MDC1-AS group. RESULTS: Compared with the control group

the apoptosis rate of T24 cells and the expression of Bax protein increased significantly

the expression of Bcl-2 protein decreased significantly

the number of migration and invasion cells decreased significantly

and the expression of MDC1-AS increased significantly after treatment with 2. 5 and 5 mg/ml lidocaine

with statistically significant difference（ P <0. 05）. Compared with the pcDNA group

the expression of MDC1-AS in T24 cells of the pcDNA-MDC1-AS group increased significantly

the apoptosis rate and the expression of Bax protein increased significantly

the number of migration and invasion cells and the expression of Bcl-2 protein decreased significantly

the differences were statistically significant（ P < 0. 05）. Compared with the lidocaine 5 mg/ml + si-NC group

the expression of MDC1-As in T24 cells decreased significantly in the lidocaine 5 mg/ml + si-MDC1-AS group

the apoptosis rate and the expression of Bax protein decreased significantly

while the number of migration and invasion cells and the expression of Bcl-2 protein increased significantly

the differences were statistically significant（ P < 0. 05）. CONCLUSIONS:Lidocaine inhibits the migration and invasion of bladder cancer cell T24 and promotes cell apoptosis by up-regulating the expression of MDC1-AS.