Self-assembling a natural small molecular inhibitor that shows aggregation-induced emission and potentiates antitumor efficacy

Sequence-Responsive Multifunctional Supramolecular Nanomicelles Act on the Regression of TNBC and Its Lung Metastasis via Synergic Pyroptosis-Mediated Immune Activation

Design of effective nanodrugs to modulate the immunosuppression of tumor microenvironment is a desirable approach to boost the clinical tumor-therapeutic effect. Supramolecular nanomicelles PolyMN-TO-8, which are constructed by self-assembling supramolecular host MTX-MPEG2000, guest NPX-2S, and TO-8 through hydrophobic forces, have excellent stability and responsiveness to carboxylesterase and glutathione in turn. In vivo studies validate that PolyMN-TO-8 enable to trigger pyroptosis-mediated immunogenic cell death under laser, avoiding the occurrence of immune dysregulation simultaneously. This therapeutic mode strengthens dendritic cells' maturation and accelerates the infiltration of CD8+ T cells into tumors through moderate activation of pro-inflammatory factors with elimination of immune-escape, ultimately making the tumor inhibition rate as high as 87.44% via synergistic functions of photodynamic therapy, photothermal therapy, chemotherapy, etc. The loss of immune-escape quickens the infiltration of CD8+ T cells into lungs, and further eschews the generation of tumor nodules in it. Chemotherapy, the release of interferon-γ, and immune memory effect also strengthen the defense against metastasis. The generation of O2 catalyzed by PolyMN-TO-8 under laser is indispensable for tumor metastasis inhibition undoubtedly.

A Carrier-Free Nanomedicine Enables Apoptosis-Ferroptosis Synergistic Breast Cancer Therapy by Targeting Subcellular Organelles

The heterogeneity of cancer cells disables the single-cell death patterns in subtypes of cells with different genotypes and phenotypes, such as refractory triple-negative breast cancer (TNBC). Therefore, the combination of multiple death modes, such as the proven cooperative apoptosis and ferroptosis, is expected to sensitize in treating TNBC. Herein, carrier-free theranostic ASP nanoparticles (NPs) were designed for wiping out TNBC by synergistic apoptosis and ferroptosis, which was self-assembled by aurantiamide acetate (Aa), scutebarbatine A (SA), and palmitin (P). Structurally, the rigid parent nucleus of SA and hydrophobic chain of P combined with the Aa to form an ordered nanostructure by noncovalent bonding forces. This self-assembly example applies to the design of nanomedicines based on more than two natural products. Notably, enhanced permeability and retention (EPR) effects and mitochondrial-lysosomal targeting empower ASP NPs to pinpoint tumor sites. Especially, Aa and P induced mitochondrial apoptosis of cancer cells, while SA and P inhibited TNBC by ferroptosis and upregulating p53. More interestingly, the combination of Aa, SA, and P enhanced the uptake of ASP NPs by cancer cell membranes. Overall, the three compounds synergize with each other to exert excellent anticancer effects.

MC1R Peptide Agonist Self-Assembles into a Hydrogel That Promotes Skin Pigmentation for Treating Vitiligo

Vitiligo, a common skin disease that seriously affects 0.5-2.0% of the worldwide population, lacks approved therapeutics due to a wide range of adverse side effects. As a key regulator of skin pigmentation, MC1R may be an effective therapeutic target for vitiligo. Herein, we report an MC1R peptide agonist that directly self-assembles into nanofibrils that form a hydrogel matrix under normal physiological conditions. This hydrogel exhibits higher stability than free peptides, sustained release, rapid recovery from shear-thinning, and resistance to enzymatic proteolysis. Furthermore, this peptidal MC1R agonist upregulates tyrosinase, tyrosinase-related protein-1 (TYRP-1), and tyrosinase-related protein-2 (TYRP-2) to stimulate melanin synthesis. More importantly, MC1R agonist hydrogel promotes skin pigmentation in mice more potently than free MC1R agonist. This study supports the development of this MC1R agonist hydrogel as a promising pharmacological intervention for vitiligo.

Preclinical development of carrier-free prodrug nanoparticles for enhanced antitumor therapeutic potential with less toxicity

Background

Nanomedicine has emerged as a promising strategy for cancer treatment. The most representative nanomedicine used in clinic is PEGylated liposomal doxorubicin DOXIL^®, which is first FDA-approved nanomedicine. However, several shortcomings, such as low drug loading capacity, low tumor targeting, difficulty in mass production and potential toxicity of carrier materials, have hindered the successful clinical translation of nanomedicines. In this study, we report a preclinical development process of the carrier-free prodrug nanoparticles designed as an alternative formulation to overcome limitations of conventional nanomedicines in the terms of technical- and industrial-aspects.

Results

The carrier-free prodrug nanoparticles (F68-FDOX) are prepared by self-assembly of cathepsin B-specific cleavable peptide (FRRG) and doxorubicin (DOX) conjugates without any additional carrier materials, and further stabilized with Pluronic F68, resulting in high drug loading (> 50%). The precise and concise structure allow mass production with easily controllable quality control (QC), and its lyophilized powder form has a great long-term storage stability at different temperatures (− 4, 37 and 60 °C). With high cathepsin B-specificity, F68-FDOX induce a potent cytotoxicity preferentially in cancer cells, whereas their cytotoxicity is greatly minimized in normal cells with innately low cathepsin B expression. In tumor models, F68-FDOX efficiently accumulates within tumor tissues owing to enhanced permeability and retention (EPR) effect and subsequently release toxic DOX molecules by cathepsin B-specific cleavage mechanism, showing a broad therapeutic spectrum with significant antitumor activity in three types of colon, breast and pancreatic cancers. Finally, the safety of F68-FDOX treatment is investigated after single-/multi-dosage into mice, showing greatly minimized DOX-related toxicity, compared to free DOX in normal mice.

Conclusions

Collectively, these results provide potential preclinical development process of an alternative approach, new formulation of carrier-free prodrug nanoparticles, for clinical translation of nanomedicines.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-022-01644-x.

Photo-Enhanced Chemotherapy Performance in Bladder Cancer Treatment via Albumin Coated AIE Aggregates

The implementation of cisplatin-based neoadjuvant chemotherapy (NAC) plays a key role in conjunction with surgical resection in preventing bladder cancer progression and recurrence. However, the significant dose-dependent toxic side effects of NAC are still a major challenge. To solve this problem, we developed a photoenhanced cancer chemotherapy (PECC) strategy based on AIEgen ((E)-3-(2-(2-(5-(4-(diphenylamino)phenyl)thiophen-2-yl)vinyl)-1,1-dimethyl-1H-3λ⁴-benzo[e]indol-3-yl)propane-1-sulfonate), which is abbreviated as BITT. Multifunctional BITT@BSA-DSP nanoparticles (NPs) were employed with an albumin-based nanocarrier decorated with the cisplatin(IV) prodrug and loaded to produce strong near-infrared fluorescence imaging (NIR FLI), and they exhibited good photoenhancement performance via photodynamic therapy (PDT) and photothermal therapy (PTT). In vitro results demonstrated that BITT@BSA-DSP NPs could be efficiently taken up by bladder cancer cells and reduced to release Pt (II) under reductase, ensuring the chemotherapy effect. Furthermore, both in vitro and in vivo evaluation verified that the integration of NIR FL imaging-guided PECC efficiently promoted the sensitivity of bladder cancer to cisplatin chemotherapy with negligible side effects. This work provides a promising strategy to enhance the sensitivity of multiple cancers to chemotherapy drugs and even achieve effective treatments for drug-resistant cancers.

Synthesis of a Thermal-Responsive Dual-Modal Supramolecular Probe for Magnetic Resonance Imaging and Fluorescence Imaging

Dual-modal imaging can integrate the advantages of different imaging technologies, which could improve the accuracy and efficiency of clinical diagnosis. Herein, a novel amphiphilic thermal-responsive copolymer obtained from three types of monomers, N-isopropyl acrylamide, 2-(acetoacetoxy) ethyl methacrylate, and propargyl methacrylate, by RAFT copolymerization, is reported. It can be grafted with β-cyclodextrin and aggregation-induced emission (AIE) luminogens tetraphenylethylene by click chemistry and Biginelli reaction. The multifunctional supramolecular polymer (P4) can be constructed by host-guest inclusion between the copolymer and the Gd-based contrast agent (CA) modified by adamantane [Ad-(DOTA-Gd)]. And it can form vesicles with a bilayer structure in aqueous which will enhance the AIE and magnetic resonance imaging effects. As fluorescent thermometer, P4 can enter HeLa cells for intracellular fluorescence imaging (FI) and is sensitive to temperature with detection limit value of 1.5 °C. As magnetic resonance CA, P4 exhibits higher relaxation compared to Magnevist, which can prolong the circulation time in vivo. In addition, Gd³⁺ in the polymer can be quickly released from the body by disassembly that reduced the biological toxicity. This work introduces new synthetic ideas for dual-modal probe, which has great potential for clinical diagnostic applications in bioimaging.

Quantitative self-assembly of pure drug cocktails as injectable nanomedicines for synergistic drug delivery and cancer therapy

New strategies to fabricate nanomedicines with high translational capacity are urgently desired. Herein, a new class of self-assembled drug cocktails that addresses the multiple challenges of manufacturing clinically useful cancer nanomedicines was reported.

Methods: With the aid of a molecular targeted agent, dasatinib (DAS), cytotoxic cabazitaxel (CTX) forms nanoassemblies (CD NAs) through one-pot process, with nearly quantitative entrapment efficiency and ultrahigh drug loading of up to 100%.

Results: Surprisingly, self-assembled CD NAs show aggregation-induced emission, enabling particle trafficking and drug release in living cells. In preclinical models of human cancer, including a patient-derived melanoma xenograft, CD NAs demonstrated striking therapeutic synergy to produce a durable recession in tumor growth. Impressively, CD NAs alleviated the toxicity of the parent CTX agent and showed negligible immunotoxicity in animals.

Conclusions: Overall, this approach does not require any carrier matrices, offering a scalable and cost-effective methodology to create a new generation of nanomedicines for the safe and efficient delivery of drug combinations.