摘要
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.
4-甲基哌嗪-1-二硫代甲酸-(3-氰基-3,3-二苯基)丙酯盐酸盐(TM208)是一种新合成的氨基二硫代甲酸酯类化合物,具有良好的体内抗肿瘤作用,且毒性较低。探讨TM208与临床已知抗癌药联用能否提高疗效并降低毒性,可为TM208的临床试验提供依据。本实验通过小鼠肝癌H_(22)移植瘤模型考察了TM208与顺铂(DDP)、环磷酰胺(CTX)、5-氟尿嘧啶(5-Fu)分别联合用药的体内抗肿瘤作用及毒性。体内实验结果证实,5-Fu(5 mg/kg/2d)与TM208(100 mg/kg/d)联用后可显著增强对H_(22)肿瘤的抑制作用(P<0.01),且几乎不增加毒性;而DDP和CTX则不能。进一步研究表明,TM208与5-Fu联用可通过下调cyclin B1,cdc2,cdk7和上调p21,p53的表达引起H_(22)实体瘤细胞发生G_2/M周期阻滞。同时此联合用药方案也可下调cyclin D1,cyclin E的表达,对cdk4,cdk2的表达则没有影响。Cdc2 mRNA的表达与其蛋白表达趋势一致,而cyclin B1mRNA表达在各组间没有差异。总之,TM208与5-Fu联用可提高抗肿瘤疗效,毒性不变,其抗肿瘤作用与细胞周期阻滞及其相关蛋白的表达变化有关。
基金
National High Technology Research and Development Program of China('863' Program,Grant No.2004AA2Z3783)
National Natural Science Foundation(Grant No.20172006 and 20672009)
