ABSTRACT
Objective To investigate the effect of transcriptional internediary factor 1 gamma (Tif1γ)and its signal pathway related proteinson apoptosis of human pancreatic cancer cell line Capan-1 treated with either gemcitabine (GEM) or raltitrexed (RTX).Methods Capan-1 cells were treated with GEM of 559 μmol/L or RTX of 0.86 μmol/L for 36 h.The cell apoptosis of Capan-1 was determined using flow cytometry.Protein levels of Tif1γ,TGF-β1,Smad3,p-Smad3,Smad4,Bcl2,BAX and Caspase3 in Capan-1 cells were determined by Western blot.Results The late apoptosis and death ratio after RTX treatment were 28.7％ ± 5.1％ and 3.7％ ± 0.5％,respectively,showing significant difference from that after GEM treatment or untreated control group (P＜0.01).The results of Western blot showed that the relative protein levels of Tif1 γ,TGF-β1,p-Smad3,BAX and Caspase3 in Capan-1 cells were increased in RTX group compared with those in GEM group or control group (P＜0.05).The relative protein levels of Smad4 and the Bcl2/Bax ratio were decreased in RTX group compared with those in GEM group or control group (P＜0.05).Conclusions Increased level of Til1γ by RTX treatment resulted in decreased level of Smad4 to regulate the balance of Bcl2/Bax,increased Caspase3 and increased apoptosis in Capan-1 cells.