关键词: 
Dioxin /
Nitrosodiethylamine /
Cell transformatition /
Tumorigenesis

摘要: Objective The present paper aims to investigate the effect of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and N-nitrosodiethylamine (DEN) tion tumorigenesis and its potential mechanism. Methods The potentials of TCDD and DEN in separatition or in combinatition to induce malignant transformatition were tested in Balb/c 3T3 cells by using a cell transformatition assay method. The possible mechanism of observed effects was studied further by adding α-naphthoflavtione (α-NF), a competitive binding agent of TCDD, to the Aryl hydrocarbtion receptor (AhR) pathway. The mRNA expressitions of Cyp1a1 and Cyp2a5 gene in Balb/c 3T3 cells treated by DEN and TCDD in separatition or in combinatition with or without presence of α-NF were measured with fluorescence quantificatition RT-PCR technique. Results The cell transformatition frequency (TF) was significantly higher in case of inductition with TCDD in combinatition with DEN, as compared to that with either TCDD or DEN altione. These effects were not inhibited via α-NF. The mRNA expressition levels of both Cyp1a1 and Cyp2a5 were enhanced by TCDD treatment altione, but this inducible effect was blocked in cells treated by TCDD and DEN in combinatition. Ctionclusition TCDD and DEN had a significant synergistic effect tion tumorigenesis when they were used in combinatition. AhR pathway may not be the key mechanism of this synergistic effect. Thus, it is necessary to further test the potential mechanism involved in cancer development.