A Deep Dive: SIWV Tetra-Peptide Enhancing the Penetration of Nanotherapeutics into the Glioblastoma

Peptide-Hitchhiking for the Development of Nanosystems in Glioblastoma

Glioblastoma (GBM) remains the epitome of aggressiveness and lethality in the spectrum of brain tumors, primarily due to the blood-brain barrier (BBB) that hinders effective treatment delivery, tumor heterogeneity, and the presence of treatment-resistant stem cells that contribute to tumor recurrence. Nanoparticles (NPs) have been used to overcome these obstacles by attaching targeting ligands to enhance therapeutic efficacy. Among these ligands, peptides stand out due to their ease of synthesis and high selectivity. This article aims to review single and multiligand strategies critically. In addition, it highlights other strategies that integrate the effects of external stimuli, biomimetic approaches, and chemical approaches as nanocatalytic medicine, revealing their significant potential in treating GBM with peptide-functionalized NPs. Alternative routes of parenteral administration, specifically nose-to-brain delivery and local treatment within the resected tumor cavity, are also discussed. Finally, an overview of the significant obstacles and potential strategies to overcome them are discussed to provide a perspective on this promising field of GBM therapy.

Porous silicon surface modification via a microwave-induced in situ cyclic disulfide (S-S) cleavage and Si-S bond formation

Porous silicon (pSi) materials have gained a great deal of attention from various research fields, and their surface-functionalization is one of the critical points for their applications. In this study, a new surface modification method of Si-H-terminated pSi materials via microwave-induced Si-S bond formation is disclosed. The silicon hydride (Si-H) functionality on the pSi surface could react with the 5-membered cyclic disulfide (S-S) compound (DL-α-lipoic acid in this study) by microwave-induced in situ S-S bond cleavage and Si-S bond formation. This surface chemistry is fast responsive (<10 min) and more efficient than other methods such as vortexing, heating stirring, or ultrasonication. The reaction maintains the primary porous structure of pSi materials including pSi wafer, pSi rugate filer, and pSi nanoparticles. An additional functional group such as carboxylic acid is demonstrated to be readily introducible on the pSi surface for further applications. Overall, this study has successfully demonstrated the porous silicon surface modification via a microwave-induced in situ cyclic disulfide (S-S) cleavage and Si-S bond formation.

Recent Advances on Surface-Modified GBM Targeted Nanoparticles: Targeting Strategies and Surface Characterization

Glioblastoma multiforme (GBM) is the most common malignant brain tumor, associated with low long-term survival. Nanoparticles (NPs) developed against GBM are a promising strategy to improve current therapies, by enhancing the brain delivery of active molecules and reducing off-target effects. In particular, NPs hold high potential for the targeted delivery of chemotherapeutics both across the blood-brain barrier (BBB) and specifically to GBM cell receptors, pathways, or the tumor microenvironment (TME). In this review, the most recent strategies to deliver drugs to GBM are explored. The main focus is on how surface functionalizations are essential for BBB crossing and for tumor specific targeting. We give a critical analysis of the various ligand-based approaches that have been used to target specific cancer cell receptors and the TME, or to interfere with the signaling pathways of GBM. Despite the increasing application of NPs in the clinical setting, new methods for ligand and surface characterization are needed to optimize the synthesis, as well as to predict their in vivo behavior. An expert opinion is given on the future of this research and what is still missing to create and characterize a functional NP system for improved GBM targeting.

Sceptrin-Au nano-aggregates (SANA) for overcoming drug-resistant Gram-negative bacteria

One of the recent advances in medical nanotechnology has been the development of nanoformulations to overcome drug-resistant bacterial infections. Herein, we disclose a new nano-antibiotic formulation based on sceptrin-Au nano-aggregates (SANA), which are drug-metal ion multiple complexes. Sceptrin is a natural compound from a marine organism (sponge) and was reported as a potential compound with drug activities. SANA consists of a sceptrin-Au ion and is a self-assembled nano-formation with electrostatic interaction. Interestingly, SANA showed superior antibiotic/antibiofilm activity toward carbapenem-resistant Gram-negative bacteria with low toxicity to red blood cells and endothelial cells. The working mechanism of SANA was identified with analysis of the extracellular reactive oxygen species level and membrane depolarization of bacteria. The feasibility of SANA as a new nano-antibiotic was demonstrated in CRPA-contaminated medical supplies where SANA inhibited the formation of biofilms as well as the growth of CRPA. This work presents a new concept for the development of next-generation nano-antibiotics and a more feasible clinical translational pathway.