Glioblastoma, the most common, aggressive brain tumor, ranks among the least curable cancers—owing to its strong tendency for intracranial dissemination, high proliferation potential, and inherent tumor resistance to radiation and chemotherapy. Current glioblastoma treatment strategies are further hampered by a critical challenge: adverse, non-specific treatment effects in normal tissue combined with the inability of drugs to penetrate the blood brain barrier and reach the tumor microenvironment. Thus, the creation of effective therapies for glioblastoma requires development of targeted drug-delivery systems that increase accumulation of the drug in the tumor tissue while minimizing systemic toxicity in healthy tissues. As demonstrated in various preclinical glioblastoma models, macromolecular drug carriers have the potential to improve delivery of small molecule drugs, therapeutic peptides, proteins, and genes to brain tumors. Currently used macromolecular drug delivery systems, such as liposomes and polymers, passively target solid tumors, including glioblastoma, by capitalizing on abnormalities of the tumor vasculature, its lack of lymphatic drainage, and the enhanced permeation and retention (EPR) effect. In addition to passive targeting, active targeting approaches include the incorporation of various ligands on the surface of macromolecules that bind to cell surface receptors expressed on specific cancer cells. Active targeting approaches also utilize stimulus responsive macromolecules which further improve tumor accumulation by triggering changes in the physical properties of the macromolecular carrier. The stimulus can be an intrinsic property of the tumor tissue, such as low pH, or extrinsic, such as local application of ultrasound or heat. This review article explores current preclinical studies and future perspectives of targeted drug delivery to glioblastoma by macromolecular carrier systems, including polymeric micelles, nanoparticles, and biopolymers. We highlight key aspects of the design of diverse macromolecular drug delivery systems through a review of their preclinical applications in various glioblastoma animal models. We also review the principles and advantages of passive and active targeting based on various macromolecular carriers. Additionally, we discuss the potential disadvantages that may prevent clinical application of these carriers in targeting glioblastoma, as well as approaches to overcoming these obstacles.
We investigated the anticancer activity of 11-hydroxyaclacinomycin X (ID-6105), a novel anthracycline, on weakly doxorubicin (Dox)-resistant SK-OV-3 ovarian cancer cells, and elucidated the relationship between its anticancer activity and accumulation in cells compared with those of Dox. Accumulation of ID-6105 in the cells was time-and concentration-dependent, a result of drug-induced cytotoxicity in the cells. SK-OV-3 cells were preloaded with ID-6105 or Dox for 12 h at concentrations ranging from 100 to 2000 nM and then incubated with drug-free medium for 0-48 h. Cell viability was measured using a proliferation-based assay (XTT assay). The inhibitory effects of ID-6105 on cell viability were more pronounced than those of Dox. The IC(50) values of ID-6105 after 24-and 48-h incubation with drug-free medium were 1.58 and 0.084 microM, while those of Dox were 2 and 0.334 microM, respectively. To investigate the relationship between the intracellular levels and the cytotoxic effects of the drugs, we preloaded SKOV-3 cells with ID-6105 or Dox (100-2000 nM) for 12 h and then measured the intracellular levels of drugs by HPLC in drug-free medium for 0-48 h. After preloading the drugs, the intracellular concentrations of ID-6105 at time 0 were 1.3-, 1.8-, and 1.4-fold larger than those of Dox at initial concentrations of 500, 1000, and 2000 nM, respectively. The extent of ID-6105 accumulation in the cells was more pronounced than that of Dox. These findings suggest that ID-6105 effluxed less from the cells than Dox, resulting in its extensive cytotoxicity compared with that of Dox. These results show that accumulation of ID-6105 within tumor cells may be important for the inhibitory effects of this drug in cancer cells. ID-6105 has an antiproliferative effect on SK-OV-3 cells that is due to its cytotoxicity. This effect is more pronounced than that of Dox, and may be attributed to extensive accumulation of ID-6105 in the cells.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.