PSMA-Targeted Stably Linked "Dendrimer-Glutamate Urea-Methotrexate" as a Prostate Cancer Therapeutic
PSMA-Targeted Stably Linked "Dendrimer-Glutamate Urea-Methotrexate" as a Prostate Cancer Therapeutic
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DOI：
10.1021/bm401777w
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发表时间：
2014-03-01
影响因子：
6.2
通讯作者：
Thomas, Thommey P.
中科院分区：
文献类型：
--
作者：
Huang, Baohua;Otis, James;Thomas, Thommey P.
实现有效的基于纳米颗粒的靶向药物递送的重要标准之一是药物不会在脱靶位点过早释放。在这里，我们报告了一种血清稳定的基于树枝状聚合物的药物缀合物的临床前评价，该药物缀合物能够通过前列腺特异性膜抗原（PSMA）主动靶向前列腺癌（PC）细胞。通过不含Cu的“点击”化学将多分子PSMA结合小分子谷氨酸脲（GLA;靶向剂）和药物甲氨蝶呤（MTX）缀合至S代PAMAM树枝状聚合物（G5）。GLA通过稳定的酰胺键缀合，MTX通过酯（Es）-或酰胺（Am）-偶联缀合，分别产生G5-GLA（m）-（Es）MTXn和G5-GLA（m）-（Am）MTXn。在含血清的培养基中，游离MTX从“G5-GLA（m）-（Es）MTX n”中缓慢释放，72 h内从树枝状聚合物中释放的MTX接近8%，而G5-GLA（m）-（Am）MTX n上的MTX完全稳定。G5-GLA（m）-（Am）MTXn结合并内化到表达PSMA的LNCaP细胞中，但不结合并内化到PSMA阴性的PC 3细胞中。缀合物抑制重组二氢叶酸还原酶并在LNCaP细胞中诱导有效的细胞毒性，但在PC 3细胞中不诱导。与游离GLA的作用类似，稳定的酰胺连接的树枝状聚合物-GLA能够抑制PSMA的N-乙酰化α-连接的酸性二肽酶（NAALADase）活性。G5-GLA（m）-MTXn可用作血清稳定的纳米颗粒缀合物，以特异性且有效地靶向和治疗PSMA过表达的前列腺肿瘤。
One of the important criteria for achieving efficient nanoparticle-based targeted drug delivery is that the drug is not prematurely released at off-target sites. Here we report the preclinical evaluation of a serum-stable dendrimer-based drug conjugate capable of actively targeting into prostate cancer (PC) cells, delivered through the prostate-specific membrane antigen (PSMA). Multiple molecules of PSMA-binding small molecule glutamate urea (GLA; targeting agent) and the drug methotrexate (MTX) were conjugated to generation S PAMAM dendrimer (G5) through Cu-free "click" chemistry. The GLA was conjugated through a stable amide bond, and the MTX was conjugated either through ester (Es)- or amide (Am)-coupling, to generate G5-GLA(m)-(Es)MTXn and G5-GLA(m)-(Am)MTXn, respectively. In serum-containing medium, free MTX was slowly released from "G5-GLA(m)-(Es)MTXn", with similar to 8% MTX released from the dendrimer in 72 h, whereas the MTX on G5-GLA(m)-(Am)MTXn was completely stable. The G5-GLA(m)-(Am)MTXn bound and internalized into PSMA-expressing LNCaP cells, but not into PSMA-negative PC3 cells. The conjugate-inhibited recombinant dihydrofolate reductase and induced potent cytotoxicity in the LNCaP cells, but not in the PC3 cells. Similar to the action of free GLA, stable amide-linked dendrimer-GLA was capable of inhibiting the enzyme N-acetylated alpha-linked acidic dipeptidase (NAALADase) activity of PSMA. The G5-GLA(m)-MTXn may serve as a serum-stable nanoparticle conjugate to specifically and effectively target and treat PSMA-overexpressing prostate tumors.