ABSTRACT
OBJECTIVE To evaluate whether the tumor promoting activity syste m based on the ex-pression of 22 tumor pro motion marker genes in Bhas 42 cell transformation assay can be developed to be a new screening technique for predicting tumor promoting potential of che mical.METHODS Chose the 12-O-tetradecanoylphorbol-13-acetate (TPA)as positive che mical and use the Bhas 42 cell lines as test syste m.Define the day of seeding cells as d 0.On d 4,medium in each well was changed with the medium DF5F containing 0.05 mg·L -1 TPA or 0.5 %DMSO,after treat for 24,48 and 72 hrs,collect the cell samples.Extract the RNA fro m the cell samples and detect the expression of Ccnb1 ,Rif1 , Mc m3,Chek1 ,Jun,Fosl1 ,Hells,Vegfa,St mn1 ,Prl2c3,Scarb1 ,Phex,Orm1 ,Orm2,Nup54, Slc2a1 ,Il1 rl1 ,Rad51 ap1 ,Tfrc,Ab1 ,Car13 and Pik3r5 at different ti mepoints by RT-PCR.RESULTS Co mpared to the negative group,the expression of 3 genes was increased after treat with TPA for 24 hr which are Vegfa,Il1 rl1 and Pik3r5;the expression of 12 genes was increased after treat with TPA for 48 hr which are Chek1 ,Hells,Mc m3,Rad51 ap1 ,Vegfa,Il1 rl1 ,Prl2c3,Slc2a1 ,Tfrc,Ab1 ,St mn1 and Rif1 ;the expression of 10 genes was increased after treat with TPA for 72 hr which are Chek1 ,Hells, Rad51 ap1 ,Vegfa,Il1 rl1 ,Prl2c3,Slc2a1 ,Tfrc,St mn1 and Ccnb1 .CONCLUSION The 22 tumor pro-motion marker genes showed different sensitivity to the positive control che mical at different ti mepoints after treat with TPA.The result was consistent with the pro motion activity of TPA.The 22 tumor pro motion marker genes combined with the Bhas 42 cell transformation assay can be developed to be a new screening technique for predicting tumor promoting potential of che mical.