Promoting Dual-Targeting Anticancer Effect by Regulating the Dynamic Intracellular Self-Assembly

Synthetic Nanoassemblies for Regulating Organelles: From Molecular Design to Precision Therapeutics

Each organelle referring to a complex multiorder architecture executes respective biological processes via its distinct spatial organization and internal microenvironment. As the assembly of biomolecules is the structural basis of living cells, creating synthetic nanoassemblies with specific physicochemical and morphological properties in living cells to interfere or couple with the natural organelle architectures has attracted great attention in precision therapeutics of cancers. In this review, we give an overview of the latest advances in the synthetic nanoassemblies for precise organelle regulation, including the formation mechanisms, triggering strategies, and biomedical applications in precision therapeutics. We summarize the emerging material systems, including polymers, peptides, and deoxyribonucleic acids (DNAs), and their respective intermolecular interactions for intercellular synthetic nanoassemblies, and highlight their design principles in constructing precursors that assemble into synthetic nanoassemblies targeting specific organelles in the complex cellular environment. We further showcase the developed intracellular synthetic nanoassemblies targeting specific organelles including mitochondria, the endoplasmic reticulum, lysosome, Golgi apparatus, and nucleus and describe their underlying mechanisms for organelle regulation and precision therapeutics for cancer. Last, the essential challenges in this field and prospects for future precision therapeutics of synthetic nanoassemblies are discussed. This review should facilitate the rational design of organelle-targeting synthetic nanoassemblies and the comprehensive recognition of organelles by materials and contribute to the deep understanding and application of the synthetic nanoassemblies for precision therapeutics.

Recent Progress of pH-Responsive Peptides, Polypeptides, and Their Supramolecular Assemblies for Biomedical Applications

Peptides and polypeptides feature a variety of active functional groups on their side chains (including carboxylic acid, hydroxyl, amino, and thiol groups), enabling diverse chemical modifications. This versatility makes them highly valuable in stimuli-responsive systems. Notably, pH-responsive peptides and polypeptides, due to their ability to respond to pH changes, hold significant promise for applications in cellular pathology and tumor targeting. Extensive researches have highlighted the potentials of low pH insertion peptides (pHLIPs), peptide-drug conjugates (PDCs), and antibody-drug conjugates (ADCs) in biomedicine. Peptide self-assemblies, with their structural stability, ease of regulation, excellent biocompatibility, and biodegradability, offer immense potentials in the development of novel materials and biomedical applications. We also explore specific examples of their applications in drug delivery, tumor targeting, and tissue engineering, while discussing future challenges and potential advancements in the field of pH-responsive self-assembling peptide-based biomaterials.

From cells to subcellular organelles: Next-generation cancer therapy based on peptide self-assembly

Due to the editability, functionality, and excellent biocompatibility of peptides, in situ self-assembly of peptides in cells is a powerful strategy for biomedical applications. Subcellular organelle targeting of peptides assemblies enables more precise drug delivery, enhances selectivity to disease cells, and mitigates drug resistance, providing an effective strategy for disease diagnosis and therapy. This reviewer first introduces the triggering conditions, morphological changes, and intracellular locations of self-assembling peptides. Then, the functions of peptide assemblies are summarized, followed by a comprehensive understanding of the interactions between peptide assemblies and subcellular organelles. Finally, we provide a brief outlook and the remaining challenges in this field.

Design, synthesis and anticancer evaluation of novel oncolytic peptide-chlorambucil conjugates

Nitrogen mustards (NMs) are an important class of chemotherapeutic drugs and have been widely employed for the treatment of various cancers. However, due to the high reactivity of nitrogen mustard, most NMs react with proteins and phospholipids within the cell membrane. Therefore, only a very small fraction of NMs can reach the reach nucleus, alkylating and cross-linking DNA. To efficiently penetrate the cell membrane barrier, the hybridization of NMs with a membranolytic agent may be an effective strategy. Herein, the chlorambucil (CLB, a kind of NM) hybrids were first designed by conjugation with membranolytic peptide LTX-315. However, although LTX-315 could help large amounts of CLB penetrate the cytomembrane and enter the cytoplasm, CLB still did not readily reach the nucleus. Our previous work demonstrated that the hybrid peptide NTP-385 obtained by covalent conjugation of rhodamine B with LTX-315 could accumulate in the nucleus. Hence, the NTP-385-CLB conjugate, named FXY-3, was then designed and systematically evaluated both in vitro and in vivo. FXY-3 displayed prominent localization in the cancer cell nucleus and induced severe DNA double-strand breaks (DSBs) to trigger cell apoptosis. Especially, compared with CLB and LTX-315, FXY-3 exhibited significantly increased in vitro cytotoxicity against a panel of cancer cell lines. Moreover, FXY-3 showed superior in vivo anticancer efficiency in the mouse cancer model. Collectively, this study established an effective strategy to increase the anticancer activity and the nuclear accumulation of NMs, which will provide a valuable reference for future nucleus-targeting modification of nitrogen mustards.

In situ stimulus-responsive self-assembled nanomaterials for drug delivery and disease treatment

The individual motifs that respond to specific stimuli for the self-assembly of nanomaterials play important roles. In situ constructed nanomaterials are formed spontaneously without human intervention and have promising applications in bioscience. However, due to the complex physiological environment of the human body, designing stimulus-responsive self-assembled nanomaterials in vivo is a challenging problem for researchers. In this article, we discuss the self-assembly principles of various nanomaterials in response to the tissue microenvironment, cell membrane, and intracellular stimuli. We propose the applications and advantages of in situ self-assembly in drug delivery and disease diagnosis and treatment, with a focus on in situ self-assembly at the lesion site, especially in cancer. Additionally, we introduce the significance of introducing exogenous stimulation to construct self-assembly in vivo. Based on this foundation, we put forward the prospects and possible challenges in the field of in situ self-assembly. This review uncovers the relationship between the structure and properties of in situ self-assembled nanomaterials and provides new ideas for innovative drug molecular design and development to solve the problems in the targeted delivery and precision medicine.

Host-guest interaction-based supramolecular prodrug self-assemblies for GSH-consumption augmented chemotherapy

The over-expressed cellular glutathione (GSH) severely restricts the chemotherapeutic efficacy due to the GSH-induced detoxification of chemical drugs. Herein, how to construct effective drug delivery systems with GSH-consumption property is still a general concern and a major challenge. In this study, the host-guest interactions between water-soluble pillar[6]arene (WP[6]) and chlorambucil-arylboronic acid (Cb-BA) were utilized to construct supramolecular prodrug self-assemblies (SPSAs) with specific stimuli-responsive property. Notably, the BA moiety could not only consume GSH but also rapidly bind curcumin (Cur), which could inhibit the thioredoxin reductase (TrxR) to further reduce the GSH biosynthesis pathway. Benefiting from the functionality of BA-Cur conjugates, the GSH levels could be significantly downregulated, paving a novel way to enhance chemotherapeutic efficacy. In vitro and in vivo investigations demonstrated that this two-pronged GSH-depletion strategy could amplify the cellular oxidative stress and achieve excellent anti-tumor efficacy.

Smart Nanogatekeepers for Tumor Theranostics

Nanoparticulate drug delivery systems (nano-DDSs) are required to reliably arrive and persistently reside at the tumor site with minimal off-target side effects for clinical theranostics. However, due to the complicated environment and high interstitial pressure in tumor tissue, they can return to the bloodstream and cause secondary side effects in normal organs. Recently, a number of nanogatekeepers have been engineered via structure-transformable/stable strategies to overcome this undesirable dilemma. The emerging structure-transformable nanogatekeepers for tumor imaging and therapy are first overviewed here, particularly for nanogatekeepers undergoing structural transformation in tumor microenvironments, cell membranes, and organelles. Thereafter, intelligent structure-stable nanogatekeepers through reversible activation and artificial individualization receptors are overviewed. Finally, the ongoing challenges and prospects of nanogatekeepers for clinical translation are briefly discussed.