Combined Tumor– and Neovascular-“Dual Targeting” Gene/Chemo-Therapy Suppresses Tumor Growth and Angiogenesis.
- 1State Key Laboratory of Biotherapy/Geriatrics and Cancer Center, West China Hospital, and Collaborative Innovation Center for Biotherapy, Sichuan University , Chengdu 610041, China.
- 2College of Pharmacy, Southwest University for Nationalities , Chengdu 610041, China.
- 3Department of Pathology/Collaborative Innovation Center of Biotherapy, Medical School of Nankai University , Tianjin 300071, China.
A rational combination is critical to achieve efficiently synergistic therapeutic efficacy for tumor treatment. Hence, we designed novel antitumor combinations (T-NPs) by integrating the tumor vascular and tumor cells dual–targeting ligand with antiangiogenesis/antitumor agents. The truncated bFGF peptide (tbFGF), which could effectively bind to FGFR1 overexpressed on tumor neovasculature endothelial cells and tumor cells, was selected to modify PLGA nanoparticles (D/P-NPs) simultaneously loaded with PEDF gene and paclitaxel in this study. The obtained T-NPs with better pharmaceutical properties had elevated cytotoxicity and enhanced expression of PEDF and α-tubulin on FGFR1-overexpressing cells. The uptake of T-NPs increased in C26 cells, probably mediated by tbFGF via specific recognization of the overexpressed FGFR1. T-NPs dramatically disrupted the tube formation of primary human umbilical vein endothelial cells (HUVECs) and displayed improved antiangiogenic activity in the transgenic zebrafish model and the alginate-encapsulated tumor cell model. More importantly, T-NPs achieved a markedly higher antitumor efficacy in the C26 tumor-bearing mice model. The antitumor effect involved the inhibition of tumor cell proliferation and angiogenesis, induction of apoptosis, and down-regulation of FGFR1. The enhanced antitumor activity of T-NPs probably resulted from the raised distribution in tumor tissues. In addition, T-NPs had no obvious toxicity as evaluated by weight monitoring, serological/biochemical analyses, and H&E staining. These results revealed that T-NPs, an active targeting gene/chemo-therapy, indeed had superior antitumor efficacy and negligible side effect, suggesting that this novel combination is a potential tumor therapy and a new treatment strategy and that the tbFGF modified nanoparticles could be applied to a wide range of tumor-genetic therapies and/or tumor-chemical therapies.
KEYWORDS: FGF receptors; active targeting nanoparticles; codelivery; paclitaxel; pigment epithelium-derived factor gene; truncated bFGF peptide
- PMID: 27615739; DOI:10.1021/acsami.6b08603
Combination therapy of multiple therapeutic strategies with synergistic effects is becoming a promising approach for cancer treatment  . Particularly, co-delivery of DNA and chemotherapeutics has shown great promise to achieve the combined effects in cancer therapy  . However, to move this laboratory technology to clinics, there are some problems that should be addressed. One of the most important strategies is to develop an efficient co-delivery system to increase efficiency and reduce toxicity. In our previous study, a co-delivery system of PEDF gene and PTX (PEDF/PTX) in a single PEG-PLGA nanoparticle (D/P-NP) was developed. The D/P-NPs are particularly appealing because they have the potential to simultaneously deliver genes and anti-cancer drugs. The co-delivery of gene and drug from self-assembled PLGA nanoparticles efficiently suppresses cancer growth by reducing side effects of chemotherapy and improves the chemosensitivity. However, this novel polymeric nanomedicine widely distributed in liver and spleen except in tumor tissues. Thus, to specifically transport PEDF/PTX combinations to the same tumor cells might further enhance the anti-cancer effect. Fibroblast growth factor receptors (FGFRs), which are overexpressed on the surface of a variety of tumor cells   and tumor neovasculature in situ  , have been found to be potential targets for tumor- and vascular-targeting therapy  . Thus, in this study, we designed novel anti-tumor combinations by organically integrating the tumor vascular/tumor cells dual-targeting ligand with anti-angiogenesis/anti-tumor agents for the first time. Specifically, a novel tbFGF-mediated active targeting delivery system simultaneously loaded with PEDF gene and PTX (T-NPs) was firstly fabricated by a self-assembly procedure. The therapeutic effects of T-NPs were systemically investigated in vitro and in vivo. T-NPs exhibited superior antiangiogenic and antitumor effects, due to the combination of PEDF gene and PTX as well as the tbFGF modification. This FGFR-mediated drug delivery system has several advantages: (1) a simple and optimal surface modification method via electrostatic interactions; (2) enhanced specific cellular uptake and cytotoxicity on tumor cells which over-express FGFRs; (3) maximal accumulation in tumor site via tbFGF which could bind specifically to FGFRs on tumors; (4) “double targeting” tumor therapies (tumor- and vescular-targeting) via single drug delivery system; (5) potential therapeutic efficacy of combined gene/chemo-therapy; (6) least toxicity to normal organs. Altogether, the findings of our study represent an important step in advancing the use of T-NPs as a potent strategy to treat tumors that overexpress FGFRs. Fig1 showed the preparation of T-NPs, as well as the extracellular and intracellular delivery of gene and chemical drug.
Fig1. Schematic diagram for preparation of the T-NPs and its mechanism of gene/chemical drug intracellular delivery. (a) Entry of the nanoparticle into endosome by the interaction of the ligand tbFGF with FGFR1, as well as endocytosis. (b) Escape the lysosome and release gene and drug. (c) Tubulin works by interfering with normal microtubule breakdown during cell division. (d) Gene entries the nucleus and expresses PEDF.
 Gandhi, N. S.; Tekade, R. K.; Chougule, M. B. Nanocarrier mediated delivery of siRNA/miRNA in combination with chemotherapeutic agents for cancer therapy: current progress and advances. J. Control. Release. 2014, 194, 238-256.
 Zhao, F.; Yin, H.; Li, J. Supramolecular self-assembly forming a multifunctional synergistic system for targeted co-delivery of gene and drug. Biomat. 2014, 35(3), 1050-1062.
 Shi, S.; Zhu, X. C.; Guo, Q. F.; Wang, Y. J.; Zuo, T.; Luo, F.; Qian, Z. Y. Self-assembled mPEG–PCL-g–PEI micelles for simultaneous codelivery of chemotherapeutic drugs and DNA: synthesis and characterization in vitro. Int. J. Nanomed. 2012, 7, 1749-1759.
 Powers, C. J.; Mcleskey, S. W.; Wellstein, A. Fibroblast Growth Factors, Their Receptors and Signaling. Endocr.-Relat. Cancer 2000, 7:165-197.
 Terada, T.; Mizobata, M.; Kawakami, S.; Yamashita, F.; Hashida, M. Optimization of Tumor-Selective Targeting by Basic Fibroblast Growth Factor-Binding Peptide Grafted PEGylated Liposomes. J. Controlled Release 2007, 119:262-270.
 Terada, T.; Mizobata, M.; Kawakami, S.; Yabe, Y.; Yamashita, F.; Hashida, M. Basic Fibroblast Growth Factor-Binding Peptide as a Novel Targeting Ligand of Drug Carrier to Tumor cells. J. Drug Targeting 2006, 14:536-545.
 Wang, X. H.; Deng, L. Y.; Chen, X.; Pei, H. Y.; Cai, L. L.; Zhao, X.; Wei, Y. Q.; Chen, L. J. Truncated bFGF-Mediated Cationic Liposomal Paclitaxel for Tumor-Targeted Drug Delivery: Improved Pharmacokinetics and Biodistribution in Tumor-Bearing Mice. J. Pharm. Sci. 2011, 100:1196-1205.
 Chen, X.; Wang, X. H.; Wang, Y. S.; Yang, L.; Hu, J.; Xiao, W. J.; Fu, A. F.; Cai, L. L.; Li, X.; Ye, X.; Liu, Y. L.; Wu, W. S.; Shao, X. M.; Mao, Y. Q.; Wei, Y. Q.; Chen, L. J. Improved Tumor-Targeting Drug Delivery and Therapeutic Efficacy by Cationic Liposome Modified with Truncated bFGF Peptide. J. Controlled Release 2010, 145:17-25.