Glioma presents one of the most malignant brain tumors, and the therapeutic effect is often limited due to the existence of brain tumor barrier. 1.98, 1.91 and 1.53-fold over that of NP-PTX group after 0.5, 1 and 4?h, respectively. Pep-NP-PTX could improve the anti-glioma efficacy with a median survival time of 32 days, which was significantly longer than that of PTX-NP (23 days) and Taxol? (22 days). In conclusion, Pep-NP-PTX is a potential targeting drug delivery system for glioma treatment. Glioblastoma multiforme (GBM) accounts for 12C15% of all brain tumors and 50C60% of astrocytomas. The incidence of GBM is less than 10 to 100,000, but the median survival of a little over 1 year from diagnosis makes it one of the most frequent primary malignant brain tumors1. The conventional clinical treatment for GBM involves surgical debulking of the accessible tumor from the patients Vargatef kinase activity assay brain, but its diffuse invasion of the surrounding normal tissue makes the complete removal of tumor by the conventional surgical method very difficult and tumor recurrence from residual tumors very possible2,3. Consequently, chemotherapy is vital for the treating GBM. Paclitaxel (PTX) can be a powerful anticancer agent Vargatef kinase activity assay by advertising microtubule assembly, resulting in inhibition of cell induction and proliferation of apoptosis4. However, the anti-glioma aftereffect of PTX is quite limited and causes systemic part results5 frequently, due mainly to its poor permeability over the bloodstream tumor hurdle (BTB)6. Receptor-mediated endocytosis is among the mechanisms by which companies can conquer the obstacle of BTB and concurrently target mind tumor. It is widely known that tumor cells express cell surface molecules such as specific antigens or cytokine receptors7,8. The interleukin-13 receptor 2 (IL-13R2), one of the subunits of the interleukin-13 receptor, is a tumor-specific receptor which is overexpressed in GBM. Because of its nonsignaling function, IL-13R2 has no signaling box motifs and behaves as a decoy receptor9. It has been reported that IL-13R2 can Vargatef kinase activity assay undergo internalization after binding to ligand without causing activation of its signaling pathways10. Based on the high affinity with IL-13R2, Interleukin-13 (IL-13) has been used as a ligand in glioma trials of immunotoxin therapy for GBM11. IL13-PE38QQR, a conjugation complex of human IL-13 with a mutated form of pseudomonas exotoxin, can lead to pronounced antitumor activity in GBM12,13,14,15. These observations make IL-13 R2 attractive as a targeting moiety. Nanoparticulate drug delivery systems have been attracted increasing attentions in recent years. The combination of polymer nanoparticle and receptor-mediated endocytosis could provide a noninvasive alternative platform due to its active targeting property besides the passive targeting by the enhanced permeability and retention (EPR) effects of tumor16. It was reported that Pep-1 (CGEMGWVRC) peptide could facilitate polymer nanoparticles targeting to glioma via IL-13R2 endocytosis17. However, the value of Pep-1 modified copolymer nanoparticle in glioma targeting chemotherapy is yet unknown. Therefore, the objective of this study was to investigate the potential and safety of Pep-1 conjugated copolymer nanoparticles for delivering PTX as the chemotherapeutic drug to Mouse monoclonal to ELK1 the treatment of glioma. PTX-loaded PEG-PLGA nanoparticles modified with Pep-1 (Pep-NP-PTX) were developed by the emulsion/solvent evaporation method. For study, both the uptake and anti-proliferation effect of nanoparticles in C6 glioma cells were evaluated. The penetration ability across blood tumor barrier of Pep-NP-PTX was studied qualitatively and quantitatively. The anti-glioma efficacy of Pep-NP-PTX was investigated by intracranial glioma-bearing mice model. The preliminary safety of Pep-NP following intravenous injection was evaluated using healthy mice. Results Characterization of the Pep-NP-PTX The nanoparticles were ready via an emulsion/solvent evaporation technique. The mean size of NP-PTX had been 91.23??1.56?nm (Fig. 1C), after customized with Pep-1 peptide, the scale risen to 95.78??2.37?nm using the same filter size distribution of Pep-NP-PTX (Fig. 1D). TEM photos demonstrated that NP-PTX and Pep-NP-PTX had been generally spherical and of regular size Vargatef kinase activity assay (Fig. 1A,B), in keeping with the scale distribution. Because of the suggest diameters significantly less than 100?nm, such nanoparticles may accumulate even more in tumor because of the EPR effect readily. Zeta potential of Pep-NP-PTX and NP-PTX had been ?35.2??2.15?mV and ?34.5??1.74?mV, respectively, indicating that the areas of NP and Pep-NP were both strong bad charged (Desk 1). The full total result suggested how the constructed nanoparticles had an excellent stability. Open in another window Shape 1 TEM picture of NP-PTX (A) and Pep-NP-PTX (B); the scale distribution of NP-PTX (C) and Pep-NP-PTX (D). Desk 1.