【Abstract】ObjectiveTo study the antitumor effects of DNA electrotransfer in muscle (ETM) by using established animal model for human anaplastic thyroid cancer cell line TA-K.MethodsNude mice with implanted TA-K were divided into five groups including: control group, pcDNA-3 plasmid electrotransfered into muscle (pcDNA ETM group), TIMP-3 plasmid injected into muscle (TIMP-3 IM group), TIMP-3 plasmid electrotransfered into muscle (TIMP-3 ETM group), TIMP-3 plasmid electrotransfered into implanted tumor (TIMP-3 ETT group). Electrical parameters used in electrotransfer were: 200 V/cm, 20 ms/pulse; 8 pulses, 1 Hz in muscle and 600 V/cm, 20 ms/pulse; 1 pulses, 1 Hz in implanted tumor respectively. ResultsThe growth of TA-K was inhibited more significantly in the groups of TIMP-3 plasmid electrotransfered into muscle and TIMP-3 plasmid electrotransfered into implanted tumor than the other groups (P＜0.05), and the content of TIMP-3 protein in tumor tissues was higher in these two groups . ConclusionAnti-oncogene has the antitumor effects by DNA electrotransfer in muscle.