4-Methylpiperazine-l-carbodithioc-acid-3-cyano-3,3-diphenylpropyl ester hydrochloride（TM208）,a newly synthesized dithiocarbamate derivative,exhibits antitumor effect in vivo with low toxicity.However,the antitumor effect of TM208 in combination with drugs in clinical use for cytotoxic chemotherapy has not been identified.In our study,the antitumor effects and toxicities of TM208 in combination with cisplatin（DDP）,cyclophosphamide（CTX） and 5-fluorouracil（5-Fu）,respectively,were evaluated in vivo using a transplanted solid-type hepatocarcinoma H_（22） mice model.The results suggested that 5-Fu（5 mg/kg/2d） potentiated the antitumor effect of TM208（100 mg/kg/d） with significantly higher tumor inhibition rates（P0.01） and a slight elevation of toxicity;however,DDP and CTX in combination with TM208 did not exhibit similar enhanced antitumor effect.For further investigation,we found that the TM208 and 5-Fu combination therapy led to G_2/M cell cycle arrest of tumor cells in vivo by downregulating the protein expression of cyclin Bl,cdc2,cdk7,and upregulating the expression of p21 and p53.The protein expression levels of cyclin Dl and cyclin E were also downregulated in tumor cells treated with TM208 and 5-Fu,while those of cdk4 and cdk2 remained unchanged.The change of mRNA expression level of cdc2 was consistent with that of its protein in each group,while the mRNA expression of cyclin B1 remained unchanged among each group.These results demonstrated the dosage regimen of TM208 for combination therapy and could serve as evidence for clinical use of TM208 as an antineoplastic drug.
An efficient and environmental-friendly one-pot procedure has been developed for the synthesis of 1,3,4-oxadiazole-5- thioethers by the reaction of acylhydrazine with carbon disulfide and organic halides or α, β-unsaturated carbonyl compounds. The reactions were carried out in water in the presence of potassium phosphate within 2-4 h to afford the expected products in excellent yields.
To identify the metabolite and CYP450 isoforms involved in rat liver microsomal metabolism of TM208. The present study investigated the metabolism of TM208 and the effects of selective CYP450 inhibitors on the metabolism of TM208 in rat liver microsomes. Various specific inhibitors of CYP were used to identify the isoforms of CYP involved in the metabolism of TM208. The inhibitor of CYP2D and that of CYP2B had strong inhibitory effects on TM208 metabolism in a concentration-de- pendant manner, the inhibitor of CYP1A had a modest inhibitory effect, and the inhibitor of CYP3A seemed not to have an obvious inhibitory effect on TM208 metabolism. TM208 might mainly be metabolized by CYP2D and CYP2B in rat liver microsomes.
＜正＞Combining the SAR of quinazoline-based EGFR inhibitors and the research progress of dithiocarbamic acid est...
Ri-Dong Li,Xin Zhang,Peng Liu,Qi Sun,Run-Tao Li~*,Ze-Mei Ge~* State Key Laboratory of Natural and Biomimetic Drugs,School of Pharmaceutical Sciences, Peking University,38 Xueyuan Road,Beijing 100191,PR China
