Yang Yang, Hu Yunxia, Wang Yuhua, Li Jun, Liu Feng, Huang Leaf
Division of Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States.
Mol Pharm. 2012 Aug 6;9(8):2280-9. doi: 10.1021/mp300152v. Epub 2012 Jun 22.
Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related death. To explore the potential of small interfering RNA (siRNA) therapy for NSCLC, we have developed anisamide-targeted LCP to efficiently deliver siRNA into the cytoplasm of sigma receptor-expressing NSCLC cells. Targeted LCP demonstrated a 9-fold higher siRNA delivery efficiency compared to nontargeted LCP in A549 cells in vitro. To simultaneously target multiple oncogenic mechanisms, we coformulated three siRNA sequences targeting HDM2, c-myc and VEGF oncogenes, and investigated their efficacy of cell-killing in A549 and H460 cells in vitro. The results indicated that the pooled siRNA codelivered by the targeted LCP could effectively and simultaneously knock down HDM2, c-myc and VEGF expressions and significantly inhibit tumor cell growth. After iv injection of mice bearing A549 xenografted tumor with Texas Red-labeled siRNA formulated in the targeted LCP, siRNA was successfully delivered to and concentrated in the tumor cells. Repeated intravenous injections of mice with pooled siRNA formulated in the targeted LCP significantly impaired NSCLC growth in vivo (p < 0.01) for both A549 and H460 tumors, demonstrating an ED50 for the treatment of ∼ 0.2 mg/kg in A549 tumors. The enhanced antitumor activity is due to the fact that the silencing of HDM2/c-myc/VEGF could inhibit tumor proliferation and angiogenesis and also simultaneously induce tumor apoptosis. Our results demonstrate that the targeted LCP is a promising vector to deliver pooled siRNA into tumors and to achieve multiple target blocking. This is potentially a valid therapeutic modality in the gene therapy of human NSCLC.
非小细胞肺癌（NSCLC）是癌症相关死亡的主要原因。为了探索小干扰RNA（siRNA）疗法治疗NSCLC的潜力，我们开发了茴香酰胺靶向的脂质立方液晶（LCP），以有效地将siRNA递送至表达σ受体的NSCLC细胞的细胞质中。在体外A549细胞中，靶向LCP的siRNA递送效率比非靶向LCP高9倍。为了同时靶向多种致癌机制，我们将靶向HDM2、c-myc和VEGF癌基因的三条siRNA序列共同配制，并研究了它们在体外对A549和H460细胞的细胞杀伤效果。结果表明，由靶向LCP共同递送的混合siRNA可以有效且同时敲低HDM2、c-myc和VEGF的表达，并显著抑制肿瘤细胞生长。在用靶向LCP配制的德克萨斯红标记的siRNA静脉注射携带A549异种移植瘤的小鼠后，siRNA成功递送至肿瘤细胞并在其中富集。用靶向LCP配制的混合siRNA对小鼠进行重复静脉注射，对A549和H460肿瘤均显著抑制了体内NSCLC的生长（p < 0.01），表明对A549肿瘤治疗的半数有效剂量（ED50）约为0.2 mg/kg。增强的抗肿瘤活性是由于HDM2/c-myc/VEGF的沉默可抑制肿瘤增殖和血管生成，同时还能诱导肿瘤细胞凋亡。我们的结果表明，靶向LCP是一种有前景的载体，可将混合siRNA递送至肿瘤并实现多靶点阻断。这可能是人类NSCLC基因治疗中的一种有效治疗方式。
