ABSTRACT
AIM:To investigate the effect of trichostatin A(TSA)on p27kip1 gene expression in vascular smooth muscle cells.METHODS:Reverse transcription-polymerase chain reaction(RT-PCR)was used to measure the level of p27kip1 mRNA.The protein levels of p27kip1 and S-phase kinase-associated protein-2(skp2)were determined by Western blotting.20S proteasome activity was quantified by using a fluorogenic proteasome-specific substrate.RESULTS:TSA did not affect mRNA level of p27kip1 in VSMCs,but attenuated serum-induced downregulation of p27kip1 through stabilizing p27kip1 turnover.In addition,TSA decreased the expression of skp2,an F-box protein that targets p27kip1 for degradation,but had no effect on proteasome activity.CONCLUSION:TSA regulates p27kip1 expression at the post-translational level in VSMCs.
ABSTRACT
AIM: To investigate the effects of p27kip1 ge ne on DNA replication and protein synthesis in esophageal carcinoma cells. METHODS: Recombinant adenovirus Ad-p27kip1 was constructed and transf ected into esophageal carcinoma cell EC-9706, and its effects on DNA replication , protein synthesis and the growth of esophageal carcinoma cells were explored b y means of cell growth count, -TdR, -Leucine incorporation meth od and flow cytometry. RESULTS: The growth of esophageal carcino ma cells was inhibited obviously. The radioactive intensity of -TdR and -Leucine in Ad-p27kip1 group decreased significantly than that in contr ol group after EC-9706 transfection (P