Evaluation Of Anti-tumor Effect Of Neo-irinotecan Derivatives ZBH-1208in Vitro

Malignant tumor is one of the major diseases of imperiling human health. Itprevail anticancer drugs research in home and abroad. As a semi-synthetic derivativeof camptothecin, Irinotecan(CPT-11) had become a promising anti-cancer drugs inrecent years. It overcome the poor water solubility and side effects cause bycamptothecin and had shown eminent anti-tumor effect in clinic. However, resistanceand untoward reaction limits its clinical application in recent reports. Studies instructthat it is feasible to get the lower toxicity and higher the pharmacological activity bystructural modification and transformation than CPT-11.As raw materials for structural modification and transformation twelve novelderivatives of irinotecan had been tested for their antiproliferative activities in varioushuman cancer cell lines in vitro and evaluated by MTT assay for their cell cytotoxicity.ZBH-1208was the highest water-solubility and antiproliferative activity in twelvenovel derivatives.The study investigated the inhibition effect on the growth of tumor cells treatedwith neo-irinotecan derivatives ZBH-1208in vitro and probed the mechanisms. MTTassay was executed to evaluate the preliminary anti-tumor effect of ZBH-1208Cytotoxicity was assessed by the tumor cell growth inhibition rates and IC50. Theresults showed that ZBH-1208had significant anti-proliferation effects on A549,NCI-H446, HeLa, SGC-7901, MCF-7, SW1116, SMMC-7721cell lines, and wassignificant variant with concentration and time. IC50of seven cancer cell treated withZBH-1208were significantly lower than that of CPT-11(P<0.05). Comparison withCPT-11, the acetylcholinesterase inhibition rates were measured using modifiedEllman method. The ZBH-1208inhibition of acetylcholinesterase activity was lowerthan CPT-11. The results showed that the neo-irinotecan derivatives ZBH-1208wasmore efficient and lower-toxicity in significant inhibit growth of the tumor cells.Then，the antitumor mechanisms of SW1116cells treated with ZBH-1208invitro. Flow cytometry analyzed the Caspase-3expression and cycle distribution of thetumor cells treated with ZBH-1208. Western blotting was used to detect theProcaspase-3, Caspase-3, PARP and cleaved PARP. Finally, the activity of DNA Topo I was detected by agarose gel electrophoresis. The results showed that the typicalapoptotic changes were observed in tumor cells by the light microscope andfluorescence microscopy. Additionally, cell cycle of the tumor cells treated withZBH-1208were arrested in G2/M phase. The expression of active Caspase-3andcleaved PARP in the tumor cell was generally up-regulated, conversely, theexpressions of procaspase-3and PARP were down-regulated. The most of the DNAkeep its integrity superhelixed in the increasing concentration of ZBH-1208. Theresults revealed that the helicase catalytic process of DNA Topo I was affected byZBH-1208, thereby inhibiting the replication, transcription of DNA and otherprocesses, which ultimately lead to the tumor cells death.In conclusion, the present study evaluate the inhibition effect on the growth oftumor cells of neo-irinotecan derivatives ZBH-1208in vitro and further explored itsanticancer mechanisms. The proliferation of the tumor cells treated with ZBH-1208were inhibited by apoptosis induction and cell cycle arrested. ZBH-1208plays a roleof DNA Topo I inhibitors in apoptosis induction and cell cycle arrested. The studyalso provides the research, experimental and theoretical reference in structuralmodification transformation and development of similar compounds. It is a valuableanti-tumor drug in developing research and future clinic application.