Gadolinium texaphyrin–methotrexate conjugates. Towards improved cancer chemotherapeutic agents
作者:Wen-Hao Wei、Mark Fountain、Darren Magda、Zhong Wang、Phil Lecane、Mimi Mesfin、Dale Miles、Jonathan L. Sessler
DOI:10.1039/b503664j
日期:——
Conjugates between methotrexate (MTX, Matrex®, N-[4-[[(2,4-diamino-6-pteridinyl)methyl]methylamino]benzoyl]-L-glutamic acid), an antifolate cancer chemotherapeutic to which resistance is often observed, and motexafin gadolinium (MGd), an experimental agent demonstrating selective tumor localization, are described. These systems were prepared in order to test whether linking these two species would produce agents with enhanced activity relative to MTX alone. Both ester- and amide-linked conjugates were synthesized starting from MGd and MTX. The ester conjugate showed greater in vitro anti-proliferative activity against the A549 lung carcinoma cell line at short incubation times than did MTX alone. Neither the amide conjugate, nor MGd, showed any observable activity under these in vitro conditions. These results are rationalized in terms of enhanced cellular uptake of both the ester and amide conjugates that is coupled with an effective rate of release (e.g., inherent or enzyme-mediated hydrolysis) in the case of the ester-linked conjugate, but not the corresponding amide system.
甲氨蝶呤(MTX、Matrex®、N-[4-[[(2,4-二氨基-6-蝶啶基)甲基]甲基氨基]苯甲酰]-L-谷氨酸)之间的结合物,一种经常观察到耐药性的抗叶酸癌症化疗药物,和莫泰沙芬钆(MGd),一种证明选择性肿瘤定位的实验药物,被描述。制备这些系统的目的是测试连接这两个物种是否会产生相对于单独的 MTX 具有增强活性的试剂。酯连接缀合物和酰胺连接缀合物都是从 MGd 和 MTX 开始合成的。与单独的 MTX 相比,酯缀合物在短孵育时间内对 A549 肺癌细胞系表现出更强的体外抗增殖活性。在这些体外条件下,酰胺缀合物和 MGd 均未表现出任何可观察到的活性。这些结果在酯连接缀合物的情况下增强的酯和酰胺缀合物的细胞摄取以及与有效释放速率(例如固有的或酶介导的水解)相结合的方面合理化,但不是相应的酰胺系统。