Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA.
Cancer center, University of Virginia, Charlottesville, VA, USA.
Theranostics. 2018 Apr 11;8(10):2782-2798. doi: 10.7150/thno.23050. eCollection 2018.
Advances in genomics and proteomics drive precision medicine by providing actionable genetic alterations and molecularly targeted therapies, respectively. While genomic analysis and medicinal chemistry have advanced patient stratification with treatments tailored to the genetic profile of a patient's tumor, proteomic targeting has the potential to enhance the therapeutic index of drugs like poly(ADP-ribose) polymerase (PARP) inhibitors. PARP inhibitors in breast and ovarian cancer patients with BRCA1/2 mutations have shown promise. About 10% of the patients who received Olaparib (PARP inhibitor) showed adverse side effects including neutropenia, thrombocytopenia and in some cases resulted in myelodysplastic syndrome, indicating that off-target effects were substantial in these patients. Through proteomic analysis, our lab previously identified plectin, a cytolinker protein that mislocalized onto the cell surface during malignant transformation of healthy ovarian tissue. This cancer specific phenotype allowed us to image pancreatic cancer successfully using plectin targeted peptide (PTP) conjugated to nanoparticles or displayed on capsid protein of adeno-associated virus (AAV) particles. The goal of this study was to integrate the available pharmacogenomics and proteomic data to develop effective anti-tumor therapies using a targeted drug delivery approach. Plectin expression and localization in human ovarian tumor specimens were analyzed followed by confirmation of cell surface plectin localization in healthy and ovarian cancer cell lines. PTP-conjugated liposomes were prepared and their specificity for plectin+ cells was determined and . A remote loading method was employed to encapsulate a PARP inhibitor (AZ7379) into liposomes. An ideal buffer exchange method and remote loading conditions were determined based on the amount of lipid and drug recovered at the end of a remote loading process. Finally, tumor growth studies were performed to determine the efficacy of PTP liposomes in preventing PARP activity in mice bearing OVCAR8 (high grade epithelial ovarian cancer (EOC)) tumors. PTP liposomal AZ7379 delivery not only enhanced PARP inhibition but also resulted in decelerated tumor growth in mice bearing subcutaneous and intraperitoneal OVCAR8 tumors. In mice bearing subcutaneous or intraperitoneal tumors, treatment with PTP liposomes resulted in a 3- and 1.7-fold decrease in tumor volume, respectively, compared to systemic drug treatment. Targeted drug delivery assisted by genomic and proteomic data provides an adaptable model system that can be extended to effectively treat other cancers and diseases.
基因组学和蛋白质组学的进展通过提供可操作的遗传改变和针对分子的治疗方法分别推动精准医学。虽然基因组分析和药物化学已经通过针对患者肿瘤的遗传特征来定制治疗方法来推进患者分层，但蛋白质组靶向有可能增强聚（ADP-核糖）聚合酶（PARP）抑制剂等药物的治疗指数。在 BRCA1/2 突变的乳腺癌和卵巢癌患者中，PARP 抑制剂已显示出前景。约 10％接受奥拉帕利（PARP 抑制剂）治疗的患者出现不良反应，包括中性粒细胞减少症、血小板减少症，在某些情况下导致骨髓增生异常综合征，表明这些患者的脱靶效应很大。通过蛋白质组分析，我们的实验室先前鉴定了 plectin，一种在健康卵巢组织恶性转化过程中错误定位于细胞表面的细胞连接蛋白。这种癌症特异性表型使我们能够成功地使用与纳米颗粒偶联的 plectin 靶向肽（PTP）或显示在腺相关病毒（AAV）颗粒衣壳蛋白上的 PTP 来对胰腺癌进行成像。本研究的目的是整合可用的药物基因组学和蛋白质组学数据，通过靶向药物递送方法开发有效的抗肿瘤疗法。分析了人卵巢肿瘤标本中的 plectin 表达和定位，随后确认了健康和卵巢癌细胞系中细胞表面 plectin 的定位。制备了 PTP 缀合的脂质体，并确定了它们对 plectin+细胞的特异性。采用远程加载方法将 PARP 抑制剂（AZ7379）封装在脂质体中。根据远程加载过程结束时回收的脂质和药物量，确定了理想的缓冲液交换方法和远程加载条件。最后，进行了肿瘤生长研究，以确定携带 OVCAR8（高级上皮性卵巢癌（EOC））肿瘤的小鼠中 PTP 脂质体预防 PARP 活性的功效。PTP 脂质体 AZ7379 递送不仅增强了 PARP 抑制作用，而且还导致携带皮下和腹腔 OVCAR8 肿瘤的小鼠的肿瘤生长速度减慢。在携带皮下或腹腔肿瘤的小鼠中，与全身药物治疗相比，PTP 脂质体治疗导致肿瘤体积分别减少了 3 倍和 1.7 倍。基因组学和蛋白质组学数据辅助的靶向药物递送提供了一个可适应的模型系统，可扩展用于有效治疗其他癌症和疾病。
