Compound YSY-01A, a recently synthesized proteasome inhibitor, has shown potent growth-inhibitory effect on tumor cells in previous researches. However, the mechanism of its inhibitory effects, especially on cell cycle, remains largely unclear. This study aims to evaluate the correlation between cell cycle arrest effect of YSY-01A and its anti-cancer effect, and to probe the possible molecular mechanisms for its effects on human colorectal adenocarcinoma cells HT-29. The results suggested that YSY-01A significantly （P0.05） inhibited cellular proliferation of HT-29 cells in a time and concentration-dependent manner. Furthermore, YSY-01A suppressed the G 2 /M transition of HT-29 cells, whereas the mitotic inhibitor paclitaxel induced M phase accumulation. Further investigation revealed that YSY-01A significantly （P0.05） up-regulated the expression levels of a series of cell cycle related protein, such as cyclin B1, Wee1, p-cdc2 （Tyr15）, p53, p21, and p27. The HT-29 cells only exhibited typical cytotoxic symptom when YSY-01A concentration reached 0.5 μM （P0.05）, which was above the dose we used in the mechanism research. In conclusion, YSY-01A showed remarkable anti-cancer activity on HT-29 cells, and its molecular mechanisms are related to G 2 /M cell cycle transition arrest.
目的探索通过前药途径改善MG132稳定性和成药性的方法。方法基于前药设计原理,设计并合成5种MG132前药,通过体外模拟实验,即分别在p H 7.4的PBS、p H 1.0的盐酸溶液和兔血浆中,考察5种前药的稳定性及在兔血浆中MG132的释放情况。结果与结论体外模拟实验发现,前药1可作为注射类前药深入研究;前药2和3适合于作为酶靶向类前药深入研究;作为意外得到的前药4'在中性溶液中稳定,在酸性溶液和血浆中均很不稳定,故不能作为口服类前药;前药5在中性条件下和血浆中都比较稳定,但不释放M G132,可能是生成了稳定的新代谢产物。
