Study Of Anti-lung Cancer Effect And The Mechanism Of Isoalantolactone And Tumor-targeted Compound ZT-3

In this study, isoalantolactone was taken into research, which is reported to have anti-tumor effect. However, there are few reports about its anti-lung-tumor effect. Anti-lung-cancer pharmacodynamics and mechanism of isoalantolactone were taken a futher research in order to study mechanisms of natural anti-tumor compounds and develop drugs with high efficiency and low toxicity. In the second part, glutamine was selected as a target because of its characters: non essential amino acids, enrichment in tumor location, different energy metabolism and key nodes of carbon and nitrogen. This study abandons cytotoxic drug development ideas but choose the perspective of tumor metabolism as anti-tumor targets. That is why glutamine become a targeting carrier in the compound ZT-3. After coupling reaction with oxaloacetate, a simple and feasible synthetic route was designed to synthesize ZT-3. The anti-tumor efficacy evaluation and the amino acid transporter mechanism research was carried on in this article.First part : Isoalantolactone Induces A549 cells Apoptosisand the Relationship with GSTA1Isoalantolactone is a Chinese medicine monomer separated from the Inula helenium L, a part of the Oriental medicine herbs commonly used. Many reports show that isoalantolactone have anti-cancer pharmacological activities. However, its mechanisms are still unknown.Aim of the study— to investigate the anti-cancer activities and mechanisms of isoalantolactone on A549 human lung adenocarcinoma cellsMaterials and Methods—isoalantolactone induced cell apoptosis activity in A549 cells was assayed by MTT, H33258 and PCM, while Cisplatin was chosen as the positive control group and MRC-5 human embryonic lung fibroblasts was chosenas a normal control model. The concentration of the isoalantolactone was setted as 6.25 μmol/L, 12.5 μmol/L, 25 μmol/L, 50 μmol/L and 100 μmol/L. A549 cell line and MRC-5 cell line were cultured in RPMI-1640 medium supplemented with 10% FBS. The anticancer mechanisms of isoalantolactone were researched by Western Blot and Real-time PCR in order to find out the relationship between isoalantolactone and the level of GSTA1 expression.Results—it was found that isoalantolactone exhibited anti-proliferative actions in A549 cells, while the IC50 was 18.7 μM. Isoalantolactone made cell cycle arrest in the S phase and cell apoptosis which was confirmed with flow cytometry and morphological analyses. On the contrary, Isoalantolactone did not display growth inhibition in MRC-5 cells. Furthermore, with the increased concentration of isoalantolactone, the GSTA1 expression had been down-regulated.Conclusion and innovation—these results showed that the anti-proliferative effects of isoalantolactone were specific to cancer cells vs MRC-5. Isoalantolactone could induce A549 cells apoptosis probably by means of down-regulating GSTA1 expression. Isoalantolactone might be a promising anti-cancer traditional medicine monomer.Second part:the desgin, synthesis, pharmacodynamics study and mechanism of new targeting anti-cancer compound ZT-3Aim of the study—the experimenters wanted to design and synthesis of small molecule targeted compounds with broad spectrum, high efficiency and low toxicity, and evaluate its anti-tumor effect and mechanism.Materials and Methods—based on previous study about the enrichment of glutamine, the synthesis of ZT-3 was degined by the way of liquid phase reaction,which was tested by HPLC and represented by LC-MS and NMR.Then, the LD50 of compound was measured by KM mouse in the IVC condition.According to the LD50, nude mouse bearing the tumor was divided into seven groups: model group, positive injected control group, positive oral control group, ZT-3 high-dose oral group, ZT-3 high-dose injected group, ZT-3 low-dose oral group, ZT-3 low-dose injected group. The effect of ZT-3 on the growth inhibition of tumor growth in nude mice wasevaluated by the inhibition rate of tumor growth. Because of its obvious anti-tumor effect, mechanism of the ZT-3 was taken into study. A sodium ion dependent amino acid transporter ASCT2 was choosen as the research object. The experiment studied the relationship of expression of ASCT2 quantity and the ZT-3 drug concentration by RT-PCR and Western blotting.Results—The results showed that ZT-3 had a very good effect on lung cancer cell line in nude mice. The best group had 70.03% inhibition rate.PCR and Western blotting experiments illustrated that the expression of ASCT2 had a good concentration depentend on ZT-3, which proved that ZT-3 suppressed tumor growth may throught the way of ASCT2.Conclusion and innovation—synthetic route of ZT-3 is practicable, and the anti-tumor effect is significant.ASCT2 plays a important role in ZT-3 compund.