Department of Radiology, Molecular Imaging Program at Stanford (MIPS), Stanford University School of Medicine, 3155 Porter Drive, Palo Alto, California 94305, United States.
ACS Appl Mater Interfaces. 2020 Mar 11;12(10):11307-11319. doi: 10.1021/acsami.9b20071. Epub 2020 Mar 2.
Gene-directed enzyme-prodrug therapy (GDEPT) is a promising approach for cancer therapy, but it suffers from poor targeted delivery in vivo. Polyethylenimine (PEI) is a cationic polymer efficient in delivering negatively charged nucleic acids across cell membranes; however, it is highly toxic in vivo. Hence, we efficiently reduced PEI toxicity without compromising its transfection efficiency by conjugating it with poly(d,l-lactic--glycolic acid) (PLGA) and poly(ethylene glycol) (PEG) as triblock copolymers through a multistep synthetic process. The synthesized nanoparticles showed efficient delivery of loaded nucleic acids to tumor cells in vitro and in vivo in mice. We used this nanoparticle to deliver a rationally engineered thymidine kinase (TK)-p53-nitroreductase (NTR) triple therapeutic gene against hepatocellular carcinoma (HCC), where p53 tumor suppressor gene is mutated in more than 85% of cancers. TK-p53-NTR triple gene therapy restores p53 function and potentiates cancer cell response to delivered prodrugs (ganciclovir (GCV) and CB1954). We used SP94 peptide-functionalized PLGA-PEG-PEI nanoparticles for the optimal delivery of TK-p53-NTR therapeutic gene in vivo. The nanoparticles prepared from the conjugated polymer showed high loading efficiency for the DNA and markedly enhanced TK-NTR-mediated gene therapy upon the simultaneous coexpression of p53 by the concurrent rescue of the endogenous apoptotic pathway in HCC cells of both p53-mutant and wild-type phenotypes in vitro. In vivo delivery of TK-p53-NTR genes by SP94-targeted PLGA-PEG-PEI NP in mice resulted in a strong expression of suicide genes selectively in tumors, and subsequent administration of GCV and CB1954 led to a decline in tumor growth, and established a superior therapeutic outcome against HCC. We demonstrate a highly efficient approach that exogenously supplements p53 to enable synergy with the outcome of TK-NTR suicide gene therapy against HCC.
基因导向酶前药疗法（GDEPT）是一种很有前途的癌症治疗方法，但它在体内的靶向递送效果不佳。聚乙烯亚胺（PEI）是一种有效的阳离子聚合物，可将带负电荷的核酸递送到细胞膜内；然而，它在体内具有很高的毒性。因此，我们通过多步合成过程，将其与聚（D，L-乳酸-乙醇酸）（PLGA）和聚乙二醇（PEG）缀合，成功地降低了 PEI 的毒性，而不影响其转染效率。合成的纳米颗粒显示出有效地将负载的核酸递送到体外和体内的肿瘤细胞中。我们使用这种纳米颗粒来传递一种经过合理设计的胸苷激酶（TK）-p53-硝基还原酶（NTR）三重治疗基因，用于治疗肝细胞癌（HCC），其中超过 85%的癌症中 p53 肿瘤抑制基因发生突变。TK-p53-NTR 三重基因治疗恢复了 p53 功能，并增强了癌细胞对递送至的前药（更昔洛韦（GCV）和 CB1954）的反应。我们使用 SP94 肽功能化的 PLGA-PEG-PEI 纳米颗粒来优化体内 TK-p53-NTR 治疗基因的传递。该聚合物制备的纳米颗粒对 DNA 具有高负载效率，并显著增强了 TK-NTR 介导的基因治疗，同时通过共表达 p53 来增强，通过同时挽救 HCC 细胞中内源性凋亡途径来增强，在 p53 突变型和野生型表型中均如此。在小鼠体内通过 SP94 靶向的 PLGA-PEG-PEI NP 传递 TK-p53-NTR 基因，导致自杀基因在肿瘤中选择性强表达，随后给予 GCV 和 CB1954 可导致肿瘤生长下降，并建立了针对 HCC 的卓越治疗效果。我们展示了一种高效的方法，该方法通过外源性补充 p53 来与 TK-NTR 自杀基因治疗针对 HCC 的结果产生协同作用。
