[1] Multifunctional nanoparticles co-delivering EZH2 siRNA and etoposide for synergistic therapy of orthotopic non-small-cell lung tumor

Yuan ZQ^#, Chen WL^#, You BG, Liu Y, Yang SD, Li JZ, Zhu WJ, Zhou XF, Liu C, Zhang XN*

Journal of Controlled Release. doi:10.1016/j.jconrel.2017.10.025  IF 7.79一区

Malignant proliferation and metastasis in non-small cell lung carcinoma (NSCLC) are great challenges for effective clinical treatment through conventional chemotherapy. The combinational therapy strategy of RNA interfering (RNAi) technology and chemotherapeutic agents have been reported to be promising for effective cancer therapy. In this study, based on multifunctional nanoparticles (NPs), the simultaneous delivery of etoposide (ETP) and anti-Enhancer of Zeste Homologue 2 (EZH2) siRNA for the effective treatment of orthotopic lung tumor was achieved. The NPs exhibited pH/redox dual sensitivity verified by particle size changes, morphological changes, and in vitro release of drugs. Confocal microscopy analysis confirmed that the NPs exhibited endosomal escape property and on-demand intracellular drug release behavior, which can protect siRNA from degradation and facilitate the chemotherapeutic effect respectively. In vitro tumor cell motility study demonstrated that EZH2 siRNA loaded in NPs can decrease the migration and invasion capabilities of tumor cells by downregulating the expression of EZH2 mRNA and protein. In particular, an antiproliferation study revealed that the co-delivery of siRNA and ETP in the multifunctional NPs can induce a synergistic therapeutic effect on NSCLC. In vivo targeting evaluation showed that cRGDyC-PEG modification on NPs exhibited a low distribution in normal organs and an obvious accumulation in orthotopic lung tumor. Furthermore, targeted NPs co-delivering siRNA and ETP showed superior inhibition on tumor growth and metastasis and produced minimal systemic toxicity. These findings indicated that multifunctional NPs can be utilized as a co-delivery system, and that the combination of EZH2 siRNA and ETP can effectively treat NSCLC.

[2] Low-density lipoprotein-coupled micelles with reduction and pH dual sensitivity for intelligent co-delivery of paclitaxel and siRNA to breast tumor

Zhu WJ^#, Yang SD^#, Qu CX, Zhu QL, Chen WL, Li F, Yuan ZQ, Liu Y, You BG, Zhang XN*

Int J Nanomed  2017,12: 3375-393 IF 4.30 一区

Multidrug resistance (MDR) is a major obstacle for the clinical therapy of malignant human cancers, and the discovery of RNA interference (RNAi) provides efficient gene silencing within tumor cells for reversing MDR. In this study, a new “binary polymer” low-density lipoprotein–N-succinyl chitosan–cystamine– urocanic acid (LDL–NSC–SS–UA), with dual pH/redox sensitivity and targeting effect was synthesized for the co-delivery of breast cancer resistance protein (BCRP) small interfering RNA (siRNA) and paclitaxel (PTX). In vivo, the co-delivering micelles can accumulate in tumor tissue via the enhanced permeability and retention (EPR) effect and the specific recognition and combination of LDL and LDLr, which is overexpressed on the surface of tumor cell membranes. The siRNA–PTX-loaded micelles inhibited gene and drug release under physiological conditions while promoted fast release in an acid microenvironment or in the presence of glutathione (GSH). The micelles escaped from the lysosome because of the proton sponge effect. Additionally, the micelles exhibited superior antitumor activity, and can downregulate the protein and mRNA expression levels of BCRP in MCF-7/taxol cells. The bio-distribution and antitumor studies proved that the siRNA–PTX-loaded micelles possessed prolonged circulation time with a remarkable tumor targeting effect and exhibited the effective inhibition of tumor growth. Therefore, the novel dual pH/redox-sensitive polymers co-delivering siRNA and PTX with excellent biocompatibility and effective reversal of MDR demonstrate a considerable potential in cancer therapy.

[3]Stepwise pH-responsive nanoparticles for enhanced cellular uptake and on-demand intracellular release of doxorubicin

Chen WL, Li F,Tang Y,Yang SD,Li JZ,Yuan ZQ,Liu Y,Zhou XF,Liu C,Zhang XN^*

Int J Nanomed. 2017,12: 4241-4256  IF 4.30 一区

Physicochemical properties, including particle size, zeta potential, and drug release behavior, affect targeting efficiency, cellular uptake, and antitumor effect of nanocarriers in a formulated drug-delivery system. In this study, a novel stepwise pH-responsive nanodrug delivery system was developed to efficiently deliver and significantly promote the therapeutic effect of doxorubicin (DOX). The system comprised dimethylmaleic acid-chitosan-urocanic acid and elicited stepwise responses to extracellular and intracellular pH. The nanoparticles (NPs), which possessed negative surface charge under physiological conditions and an appropriate nanosize, exhibited advantageous stability during blood circulation and enhanced accumulation in tumor sites via enhanced permeability and retention effect. The tumor cellular uptake of DOX-loaded NPs was significantly promoted by the first-step pH response, wherein surface charge reversion of NPs from negative to positive was triggered by the slightly acidic tumor extracellular environment. After internalization into tumor cells, the second-step pH response in endo/lysosome acidic environment elicited the on-demand intracellular release of DOX from NPs, thereby increasing cytotoxicity against tumor cells. Furthermore, stepwise pH-responsive NPs showed enhanced antiproliferation effect and reduced systemic side effect in vivo. Hence, the stepwise pH-responsive NPs provide a promising strategy for efficient delivery of antitumor agents.

[4] Binary-copolymer system base on low-density lipoprotein-coupled N-succinyl chitosan lipoic acid micelles for co-delivery MDR1 siRNA and paclitaxel, enhances antitumor effects via reducing drug.

Yang, SD^#, Zhu WJ^#, Zhu QL,Chen WL, Ren ZX, Li F,Yan ZQ, Li JZ,Liu Y, Zhou XF, Liu C, Zhang XN^*.

Biomed Mater Res B-Appl Biomater. 2017, 105(5): 1114-1125  IF 3.19 二区

The development of effective and stable carriers of small interfering RNA (siRNA) is important for treating cancer with multidrug resistance (MDR). We developed a new gene and drug co-delivery system and checked its characteristics. Low-density lipoprotein(LDL) was coupled with N-succinyl chitosan (NSC) Lipoic acid (LA) micelles and co-delivered MDR1 siRNA and paclitaxel (PTX-siRNA/LDL-NSC-LA) to enhance antitumor effects by silencing the MDR gene of tumors. In our study, we developed a new type of containing paclitaxel-loaded micelles and siRNA-loaded LDL nanoparticle. This “binary polymer” is pH and reduction dual-sensitive core-crosslinked micelles. PTX-siRNA/LDL-NSC-LA had an average particle size of 171.6 ± 6.42 nm, entrapment efficiency of 93.92% ± 1.06%, and drug-loading amount of 12.35% ± 0.87%. In vitro, MCF-7 cells, high expressed LDL receptor, were more sensitive to this delivery system than to taxol^® and cell activity was inhibited significantly. Fluorescence microscopy showed that PTX-siRNA/LDL-NSC-LA was uptaken very conveniently and played a key role in antitumor activity. PTX-siRNA/LDL-NSC-LA protected the siRNA from degradation by macrophage phagocytosis and evidently down-regulated the level of mdr1 mRNA as well as the expression of P-gp. We tested the target ability of PTX-siRNA/LDL-NSC-LA in vivo in tumor-bearing nude mice. Results showed that this system could directly deliver siRNA and PTX to cancer cells. Thus, new co-delivering siRNA and antitumor drugs should be explored for solving MDR in cancer.