A Hierarchical Peptide-Lanthanide Framework To Accurately Redress Intracellular Carcinogenic Protein-Protein Interaction

Main methods and tools for peptide development based on protein-protein interactions (PPIs)

Protein-protein interactions (PPIs) regulate essential physiological and pathological processes. Due to their large and shallow binding surfaces, PPIs are often considered challenging drug targets for small molecules. Peptides offer a viable alternative, as they can bind these targets, acting as regulators or mimicking interaction partners. This review focuses on competitive peptides, a class of orthosteric modulators that disrupt PPI formation. We provide a concise yet comprehensive overview of recent advancements in in-silico peptide design, highlighting computational strategies that have improved the efficiency and accuracy of PPI-targeting peptides. Additionally, we examine cutting-edge experimental methods for evaluating PPI-based peptides. By exploring the interplay between computational design and experimental validation, this review presents a structured framework for developing effective peptide therapeutics targeting PPIs in various diseases.

Resetting the Hsc70-mediated lysosomal degradation of PD-L1 via a supramolecular meso peptide for the restoration of acquired anti-tumor T cell immunity

The reduction of cellular PD-L1 abundance through lysosomal degradation is recognized as essential for effective and sustained targeting of PD-L1-dependent immune evasion in cancer. While Hsc70 can interact with PD-L1 to promote its lysosomal degradation, the overexpression of CMTM6 competitively inhibits this interaction, leading to the blockade of PD-L1 lysosomal degradation. To overcome this issue, a meso chimeric peptide PEPPDL1 was designed to specifically bind the PD-1 binding domain of PD-L1 instead of the Hsc70/CMTM6 binding domain, while also binding to Hsc70 to facilitate the dragging of PD-L1 into Hsc70-mediated chaperone-mediated autophagy (CMA), thereby achieving lysosomal degradation. In order to enable internalization into tumor cells, supramolecular engineering techniques were employed through terminal modification involving sulfydryl and monovalent gold ion (Au(I)), both facilitating self-assembly of modified PEPPDL1 into supramolecular nanospheres termed CTAC-PDL1 driven by aurophilic interaction. Furthermore, based on bioinformatics analysis of mRNA expression data from 30 types of tumors obtained from TCGA database, malignant melanoma was identified as the most suitable indication for CTAC-PDL1 due to its specific characteristics of tumor immune. As expected, CTAC-PDL1 effectively reactivated Hsc70-mediated lysosomal degradation of PD-L1 and consequently restored anti-tumor T cell immunity in a B16F10-derived mouse model of malignant melanoma while maintaining a favorable safety profile. Overall, this work not only presents an alternative approach for targeting PD-L1-dependent cancer immune evasion, but also provides a modularized strategy for discovering specific regulators for target proteins in various diseases.

Reinvigoration of cytotoxic T lymphocytes in microsatellite instability-high colon adenocarcinoma through lysosomal degradation of PD-L1

Compensation and intracellular storage of PD-L1 may compromise the efficacy of antibody drugs targeting the conformational blockade of PD1/PD-L1 on the cell surface. Alternative therapies aiming to reduce the overall cellular abundance of PD-L1 thus might overcome resistance to conventional immune checkpoint blockade. Here we show by bioinformatics analysis that colon adenocarcinoma (COAD) with high microsatellite instability (MSI-H) presents the most promising potential for this therapeutic intervention, and that overall PD-L1 abundance could be controlled via HSC70-mediated lysosomal degradation. Proteomic and metabolomic analyses of mice COAD with MSI-H in situ unveil a prominent acidic tumor microenvironment. To harness these properties, an artificial protein, IgP β, is engineered using pH-responsive peptidic foldamers. This features customized peptide patterns and designed molecular function to facilitate interaction between neoplastic PD-L1 and HSC70. IgP β effectively reduces neoplastic PD-L1 levels via HSC70-mediated lysosomal degradation, thereby persistently revitalizing the action of tumor-infiltrating CD8 + T cells. Notably, the anti-tumor effect of lysosomal-degradation-based therapy surpasses that of antibody-based immune checkpoint blockade for MSI-H COAD in multiple mouse models. The presented strategy expands the use of peptidic foldamers in discovering artificial protein drugs for targeted cancer immunotherapy.

A Transdermal Prion-Bionics Supermolecule as a RAB3A Antagonist for Enhancing Facial Youthfulness

The mechanism research of skin wrinkles, conducted on volunteers underwent high-intensity desk work and mice subjected to partial sleep deprivation, revealed a significant reduction in dermal thickness associated with the presence of wrinkles. This can be attributed to the activation of facial nerves in a state of hysteria due to an abnormally elevated interaction between SNAP25 and RAB3A proteins involved in the synaptic vesicle cycle (SVC). Facilitated by AI-assisted structural design, a refined peptide called RSIpep is developed to modulate this interaction and normalize SVC. Drawing inspiration from prions, which possess the ability to protect themselves against proteolysis and invade neighboring nerve cells through macropinocytosis, RSIpep is engineered to demonstrate a GSH-responsive reversible self-assembly into a prion-like supermolecule (RSIprion). RSIprion showcases protease resistance, micropinocytosis-dependent cellular internalization, and low adhesion with constituent molecules in the cuticle, thereby endowing it with the transdermic absorption and subsequent biofunction in redressing the frenzied SVC. As a facial mud mask, it effectively reduces periorbital and perinasal wrinkles in the human face. Collectively, RSIprion not only presents a clinical potential as an anti-wrinkle prion-like supermolecule, but also exemplifies a reproducible instance of bionic strategy-guided drug development that bestows transdermal ability upon the pharmaceutical molecule.

Rewiring chaperone-mediated autophagy in cancer by a prion-like chemical inducer of proximity to counteract adaptive immune resistance

Chaperone-mediated autophagy (CMA), a proteolytic system contributing to the degradation of intracellular proteins in lysosomes, is upregulated in tumors for pro-tumorigenic and pro-survival purposes. In this study, bioinformatics analysis revealed the co-occurrence of upregulated CMA and PD-L1 accumulation in metastatic melanoma with adaptive immune resistance (AIR) to anti-PD1 treatment, suggesting the potential therapeutic effects of rewiring CMA for PD-L1 degradation. Furthermore, this co-occurrence is attributed to IFN-γ-mediated compensatory up-regulation of PD-L1 and CMA, accompanied by enhanced macropinocytosis. Drawing inspiration from the cellular uptake of prions via macropinocytosis, a prion-like chemical inducer of proximity called SAP was engineered using self-assembly of the designed chiral peptide PHA. By exploiting sensitized macropinocytosis, SAP clandestinely infiltrates tumor cells and subsequently disintegrates into PHA, which reprograms CMA by inducing PD-L1 close to HSPA8. SAP degrades PD-L1 in a CMA-dependent manner and effectively restores the anti-tumor immune response in both allografting and Hu-PDX melanoma mouse models with AIR while upholding a high safety profile. Collectively, the reported SAP not only presents an immune reactivation strategy with clinical translational potential for overcoming AIR in cutaneous melanomas but serves as a reproducible example of precision-medicine-guided drug development that fully leverages specific cellular indications in pathological states.

Multifunctional Covalent Organic Framework-Based Microneedle Patch for Melanoma Treatment

Melanoma is resistant to conventional chemotherapy and radiotherapy. Therefore, it is essential to develop a targeted, low-toxic, and minimally invasive treatment. Here, DTIC/ICG-Fe3O4@TpBD BSP/HA microneedles (MNs) were designed and fabricated, which can enhance targeting to melanoma and perform photothermal therapy (PTT) and chemotherapy simultaneously to synergistically exert anticancer effects. The system consisted of magnetic nanoparticles (DTIC/ICG-Fe3O4@TpBD), dissoluble matrix (Bletilla polysaccharide (BSP)/hyaluronic acid (HA)), and a polyvinyl alcohol backing layer. Due to the good magnetic responsiveness of Fe3O4@TpBD, dacarbazine (DTIC) and indocyanine green (ICG) can be better targeted to the tumor tissue and improve the therapeutic effect. BSP and HA have good biocompatibility and transdermal ability, so that the MNs can completely penetrate the tumor tissue, be dissolved by the interstitial fluid, and release DTIC and ICG. Under near-infrared (NIR) light irradiation, ICG converts light energy into thermal energy and induces ablation of B16-OVA melanoma cells. In vivo results showed that DTIC/ICG-Fe3O4@TpBD BSP/HA MNs combined with chemotherapy and PTT could effectively inhibit the growth of melanoma without tumor recurrence or significant weight loss in mice. Therefore, DTIC/ICG-Fe3O4@TpBD BSP/HA MNs are expected to provide new ideas and therapeutic approaches for the clinical treatment of melanoma.

A d-peptide-based oral nanotherapeutic modulates the PD-1/PD-L1 interaction for tumor immunotherapy

Background

PD-1/PD-L1 immune checkpoint inhibitors are currently the most commonly utilized agents in clinical practice, which elicit an immunostimulatory response to combat malignancies. However, all these inhibitors are currently administered via injection using antibody-based therapies, while there is a growing need for oral alternatives.

Methods

This study has developed and synthesized exosome-wrapped gold-peptide nanocomplexes with low immunogenicity, which can target PD-L1 and activate antitumor immunity in vivo through oral absorption. The ^SuperPDL1^exo was characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS), Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), and gel silver staining. The transmembrane ability of ^SuperPDL1^exo was evaluated by flow cytometry and immunofluorescence. Cell viability was determined using the Cell Counting Kit-8 (CCK-8) assay. ELISA experiments were conducted to detect serum and tissue inflammatory factors, as well as serum biochemical indicators. Tissue sections were stained with H&E for the evaluation of the safety of ^SuperPDL1^exo. An MC38 colon cancer model was established in immunocompetent C56BL/6 mice to evaluate the effects of ^SuperPDL1^exo on tumor growth in vivo. Immunohistochemistry (IHC) staining was performed to detect cytotoxicity factors such as perforin and granzymes.

Results

First, ^SuperPDL1 was successfully synthesized, and milk exosome membranes were encapsulated through ultrasound, repeated freeze-thaw cycles, and extrusion, resulting in the synthesis of ^SuperPDL1^exo. Multiple characterization results confirmed the successful synthesis of ^SuperPDL1^exo nanoparticles. Furthermore, our data demonstrated that ^SuperPDL1^exo exhibited excellent colloidal stability and superior cell transmembrane ability. In vitro and in vivo experiments revealed that ^SuperPDL1^exo did not cause damage to multiple systemic organs, demonstrating its good biocompatibility. Finally, in the MC38 colon cancer mouse model, it was discovered that ^SuperPDL1^exo could inhibit the progression of colon cancer, and this tumor-suppressive effect was mediated through the activation of tumor-specific cytotoxic T lymphocyte (CTL)-related immune responses.

Conclusion

This study has successfully designed and synthesized an oral nanotherapeutic, ^SuperPDL1^exo, which demonstrates small particle size, excellent colloidal stability, transmembrane ability in tumor cells, and biocompatibility. In vivo experiments have shown that it effectively activates T-cell immunity and exerts antitumor effects.

Cocktail hepatocarcinoma therapy by a super-assembled nano-pill targeting XPO1 and ATR synergistically

Intensive cancer treatment with drug combination is widely exploited in the clinic but suffers from inconsistent pharmacokinetics among different therapeutic agents. To overcome it, the emerging nanomedicine offers an unparalleled opportunity for encapsulating multiple drugs in a nano-carrier. Herein, a two-step super-assembled strategy was performed to unify the pharmacokinetics of a peptide and a small molecular compound. In this proof-of-concept study, the bioinformatics analysis firstly revealed the potential synergies towards hepatoma therapy for the associative inhibition of exportin 1 (XPO1) and ataxia telangiectasia mutated-Rad3-related (ATR), and then a super-assembled nano-pill (gold nano drug carrier loaded AZD6738 and 97-110 amino acids of apoptin (AP) (AA@G)) was constructed through camouflaging AZD6738 (ATR small-molecule inhibitor)-binding human serum albumin onto the AP-Au supramolecular nanoparticle. As expected, both in vitro and in vivo experiment results verified that the AA@G possessed extraordinary biocompatibility and enhanced therapeutic effect through inducing cell cycle arrest, promoting DNA damage and inhibiting DNA repair of hepatoma cell. This work not only provides a co-delivery strategy for intensive liver cancer treatment with the clinical translational potential, but develops a common approach to unify the pharmacokinetics of peptide and small-molecular compounds, thereby extending the scope of drugs for developing the advanced combination therapy.

Turning chiral peptides into a racemic supraparticle to induce the self-degradation of MDM2

INTRODUCTION

Chirality is immanent in nature, and chiral molecules can achieve their pharmacological action through chiral matching with biomolecules and molecular conformation recognition.

OBJECTIVES

Clinical translation of chiral therapeutics, particularly chiral peptide molecules, has been hampered by their unsatisfactory pharmaceutical properties.

METHODS

A mild and simple self-assembly strategy was developed here for the construction of peptide-derived chiral supramolecular nanomedicine with suitable pharmaceutical properties. In this proof-of-concept study, we design a D-peptide as MDM2 Self-Degradation catalysts (MSDc) to induce the self-degradation of a carcinogenic E3 Ubiquitin ligase termed MDM2. Exploiting a metal coordination between mercaptan in peptides and trivalent gold ion, chiral MSDc was self-assembled into a racemic supraparticle (MSDNc) that eliminated the consume from the T-lymphocyte/macrophage phagocytose in circulation.

RESULTS

Expectedly, MSDNc down-regulated MDM2 in more action than its L-enantiomer termed ^CtrlMSDNc. More importantly, MSDNc preponderantly suppressed the tumor progression and synergized the tumor immunotherapy in allograft model of melanoma through p53 restoration in comparison to ^CtrlMSDNc.

CONCLUSION

Collectively, this work not only developed a secure and efficient therapeutic agent targeting MDM2 with the potential of clinical translation, but also provided a feasible and biocompatible strategy for the construction of peptide supraparticle and expanded the application of chiral therapeutic and homo-PROTAC to peptide-derived chiral supramolecular nanomedicine.

Nanomedicines Targeting Metabolism in the Tumor Microenvironment

Cancer cells reprogram their metabolism to meet their growing demand for bioenergy and biosynthesis. The metabolic profile of cancer cells usually includes dysregulation of main nutritional metabolic pathways and the production of metabolites, which leads to a tumor microenvironment (TME) having the characteristics of acidity, hypoxic, and/or nutrient depletion. Therapies targeting metabolism have become an active and revolutionary research topic for anti-cancer drug development. The differential metabolic vulnerabilities between tumor cells and other cells within TME provide nanotechnology a therapeutic window of anti-cancer. In this review, we present the metabolic characteristics of intrinsic cancer cells and TME and summarize representative strategies of nanoparticles in metabolism-regulating anti-cancer therapy. Then, we put forward the challenges and opportunities of using nanoparticles in this emerging field.

Turning a Targeting β-Catenin/Bcl9 Peptide Inhibitor into a GdOF@Au Core/Shell Nanoflower for Enhancing Immune Response to Cancer Therapy in Combination with Immune Checkpoint Inhibitors

Combination administration is becoming a popular strategy in current cancer immunotherapy to enhance tumor response to ICIs. Recently, a peptide drug, a protein–protein interaction inhibitor (PPI), that disrupts the β-catenin/Bcl9 interaction in the tumoral Wnt/β-catenin pathway has become a promising candidate drug for immune enhancement and tumor growth inhibition. However, the peptide usually suffers from poor cell membrane permeability and proteolytic degradation, limiting its adequate accumulation in tumors and ultimately leading to side effects. Herein, a gadolinium–gold-based core/shell nanostructure drug delivery system was established, where Bcl9 was incorporated into a gadolinium–gold core–shell nanostructure and formed GdOFBAu via mercaptogenic self-assembly. After construction, GdOFBAu, when combined with anti-PD1 antibodies, could effectively inhibit tumor growth and enhance the response to immune therapy in MC38 tumor-bearing mice; it not only induced the apoptosis of cancer cells, but also promoted the tumor infiltration of Teff cells (CD8⁺) and decreased Treg cells (CD25⁺). More importantly, GdOFBAu maintained good biosafety and biocompatibility during treatment. Taken together, this study may offer a promising opportunity for sensitizing cancer immunotherapy via metal–peptide self-assembling nanostructured material with high effectiveness and safety.

Nanoparticle delivery of miR-21-3p sensitizes melanoma to anti-PD-1 immunotherapy by promoting ferroptosis

Background

Although anti-programmed cell death protein 1 (PD-1) immunotherapy is greatly effective in melanoma treatment, low response rate and treatment resistance significantly hinder its efficacy. Tumor cell ferroptosis triggered by interferon (IFN)-γ that is derived from tumor-infiltrating CD8⁺ T cells greatly contributes to the effect of immunotherapy. However, the molecular mechanism underlying IFN-γ-mediated ferroptosis and related potentially promising therapeutic strategy warrant further clarification. MicroRNAs (miRNAs) participate in ferroptosis execution and can be delivered systemically by multiple carriers, which have manifested obvious therapeutic effects on cancer.

Methods

MiRNAs expression profile in IFN-γ-driven ferroptosis was obtained by RNA sequencing. Biochemical assays were used to clarify the role of miR-21-3p in IFN-γ-driven ferroptosis and the underlying mechanism. MiR-21-3p-loaded gold nanoparticles were constructed and systemically applied to analyze the role of miR-21-3p in anti-PD-1 immunotherapy in preclinical transplanted tumor model.

Results

MiRNAs expression profile of melanoma cells in IFN-γ-driven ferroptosis was first obtained. Then, upregulated miR-21-3p was proved to facilitate IFN-γ-mediated ferroptosis by potentiating lipid peroxidation. miR-21-3p increased the ferroptosis sensitivity by directly targeting thioredoxin reductase 1 (TXNRD1) to enhance lipid reactive oxygen species (ROS) generation. Furthermore, miR-21-3p overexpression in tumor synergized with anti-PD-1 antibody by promoting tumor cell ferroptosis. More importantly, miR-21-3p-loaded gold nanoparticles were constructed, and the systemic delivery of them increased the efficacy of anti-PD-1 antibody without prominent side effects in preclinical mice model. Ultimately, ATF3 was found to promote miR-21-3p transcription in IFN-γ-driven ferroptosis.

Conclusions

MiR-21–3 p upregulation contributes to IFN-γ-driven ferroptosis and synergizes with anti-PD-1 antibody. Nanoparticle delivery of miR-21–3 p is a promising therapeutic approach to increase immunotherapy efficacy without obvious systemic side effects.

Restorative biodegradable two-layered hybrid microneedles for melanoma photothermal/chemo co-therapy and wound healing

Tumor killing and wound healing are two complementary and influential processes during the treatment of melanoma. Herein, a two-layered microneedle platform was developed with bifunctional effect of chemo-photothermal synergistic melanoma therapy and skin regeneration. The bifunctional platform composed of embeddable curcumin nanodrugs/new Indocyanine Green/hyaluronic acid (Cur NDs/IR820/HA) microneedles and sodium alginate/gelatin/hyaluronic acid (SA/Ge/HA) supporting backing layer was prepared through a two-step casting process. With uniform incorporation of curcumin nanodrugs and IR820, the microneedles exhibited excellent photothermal performance under external near-infrared (NIR) light stimulation and tumor co-therapy ability. Once the embeddable microneedles were inserted into skin, they would rapidly dissolve and activate drug release successfully for tumor treatment. Moreover, the SA/Ge/HA supporting backing layer was left behind to cover the wound and promote the proliferation of endothelial and fibroblasts cells for enhanced skin regeneration. The two-layered microneedles platform can simultaneously eliminate the tumor and accelerate wounding healing, which may be potentially employed as a competitive strategy for the treatment of melanoma.

A Bionic-Homodimerization Strategy for Optimizing Modulators of Protein-Protein Interactions: From Statistical Mechanics Theory to Potential Clinical Translation

Emerging protein-protein interaction (PPI) modulators have brought out exciting ability as therapeutics in human diseases, but its clinical translation has been greatly hampered by the limited affinity. Inspired by the homodimerize structure of antibody, the homodimerization contributes hugely to generating the optimized affinity is conjectured. Herein, a statistical-mechanics-theory-guided method is established to quantize the affinity of ligands with different topologies through analyzing the change of enthalpy and the loss of translational and rotational entropies. A peptide modulator for p53-MDM2 termed CPAP is used to homodimerize connecting, and this simple homodimerization can significantly increase the affinity. To realize the cellular internalization and tumor accumulation, Dimer CPAP and Mono CPAP are nanoengineered into gold(I)-CPAP supermolecule by the aurophilic interaction-driven self-assembly. Nano-Dimer CPAP potently suppressed tumor growth in lung cancer allograft model and a patient-derived xenograft model in more action than Nano-Mono CPAP, while keeping a favorable drug safety profile. This work not only presents a physico-mechanical method for calculating the affinity of PPI modulators, but also provides a simple yet robust homodimerization strategy to optimize the affinity of PPI modulators.

Turing miRNA into infinite coordination supermolecule: a general and enabling nanoengineering strategy for resurrecting nuclear acid therapeutics

Background

Clinical translation of therapeutic nuclear acid, particularly those targeting tumor progression, has been hampered by the intrinsic weaknesses of nuclear acid therapeutic including poor systemic stability, rapid clearance, low membrane permeability and lack of targeting ability. Small nuclear acid engineered into carrier-free nanodrugs with structural stability and disease targeting may be viable to overcome pharmaceutical obstacles of nuclear acid.

Methods

A general method through a mild and simple chemistry was established to convert therapeutic miRNA into an infinite Auric-sulfhydryl coordination supramolecular miRNA termed IacsRNA with near-spherical nanostructure, high colloid as well as anti-hydrolysis stability and low macrophage uptakes.

Results

IacsRNA presented the increased half-life period in circulation and accumulation at tumor sites in comparison to normal miRNA. Moreover, Iacs-miR-30c showed no toxicity of viscera and sanguis system in the 5-time injection dosage of the treatment. More importantly, Iacs-miR-30c potently suppressed the Wnt signaling pathway in vitro and in vivo, and effectively sensitized both potency of 5-Fu in PDX model of colon cancer and Anti-PD1 in B16F10 homograft model of melanoma.

Conclusion

Collectively, this work amply confirmed the design of IacsRNA as a general and viable strategy of nano-pharmaceutic to concert flimsy therapeutic miRNA into potential drugs. Considering from a broader perspective, the miRNA-initiated infinite coordination self-assembly strategy has distinct advantages in resurrecting nuclear acid therapeutics, probably bringing new inspiration to RNA-derived therapeutics of a great variety of human diseases including cancer.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-021-01212-9.

A Tumor-Targeting Metal-Organic Nanoparticle Constructed by Dynamic Combinatorial Chemistry toward Accurately Redressing Carcinogenic Wnt Cascade

Targeted and immunological therapy have revolutionized the malignancy treatment, but is suffering from the dose-limiting side effects and inadequate responsiveness. The emerging nanoscale infinite coordination polymers provide a feasible strategy for tumor targeting and immune sensitization. Herein, a "one-pot" self-assembled strategy based on dynamic combinatorial chemistry (DCC) principle is designed to construct a tumor-targeting metal-organic nanoparticle (MOICP) through a spontaneous co-assembling among three metal-organic coordination polymers tuned by a Wnt-inhibitor carnosic acid (CA). Responding to the tumor microenvironment, MOICP presents an optimized tumor-preferential accumulation and the satisfactory biosafety. MOICP is more active in vitro and in vivo than CA in suppressing of Wnt signaling pathway, and potently inhibits tumor growth in a patient-derived xenograft model of Wnt-activated pancreatic carcinoma. Moreover, MOICP reverses the lack of intratumoral infiltration of T lymphocytes, and hence augments the action of Anti-PD1 (programmed cell death protein 1) immunotherapy in B16F10 melanoma allograft mice model. This clinically viable MOICP can not only be applied to Wnt inhibition for cancer targeted therapy and immunotherapeutic sensitization, but also provides a de novo pattern for nanomedicine architecture with cargo-initiated co-self-assembly guided by DCC, thereby bringing new inspiration in general for disease intervention.

Assembling BH3-mimic peptide into a nanocluster to target intracellular Bcl2 towards the apoptosis induction of cancer cell

Bcl-2, an anti-apoptotic protein, is always overexpressed in tumor cells to suppress the pro-apoptotic function of Bax, thereby prolonging the life of the tumor. However, BH3 proteins could directly activate Bax via antagonizing Bcl-2 to induce apoptosis in response to the stimulation. Thus, mimicking BH3 proteins with a peptide is a potential strategy for anti-cancer therapy. Unfortunately, clinical translation of BH3-mimic peptide is hindered by its inefficacious cellular internalization and proteolysis resistance. Herein, we translated a BH3-mimic peptide into a peptide-auric spheroidal nanocluster (BH3-AuNp), in which polymeric BH3-Auric precursors [Au¹⁺-S-BH3]_narein situself-assembled on the surface of gold nanoparticles by a one-pot synthesis. Expectedly, this strategy could improve the anti-proteolytic ability and cytomembrane penetrability of the BH3 peptide. As a result, BH3-AuNp successfully induced the apoptosis of two cancer cell lines by an order of magnitude compared to BH3. This therapeutic and feasible peptide nano-engineering strategy will help peptides overcome the pharmaceutical obstacles, awaken its biological functions, and possibly revive the research about peptide-derived nanomedicine.

Nanotherapeutic approach to tackle chemotherapeutic resistance of cancer stem cells

Estimates indicate that cancer will become the leading cause of mortality worldwide in the future. Tumorigenesis is a complex process that involves self-sufficiency in signs of growth, insensitivity to anti-growth signals, prevention of apoptosis, unlimited replication, sustained angiogenesis, tissue invasion, and metastasis. Cancer stem cells (CSCs) have an important role in tumor development and resistance. Here we will approach phenotypic plasticity capacity, highly efficient DNA repair systems, anti-apoptotic machinery, sustained stemness features, interaction with the tumor microenvironment, and Notch, Wnt, and Hedgehog signaling pathways. The researches about CSCs as a target in cancer treatment has been growing. Many different options have pointed beneficial results, such as pathways and CSC-surface markers targeting. Besides its limitations, nanotherapeutics have emerged as a potential strategy in this context since they aim to improve pharmacokinetics, biodistribution, and reduce the side effects observed in traditional treatments. Nanoparticles have been studied in this field, mostly for drug delivery and a multitherapy approach. Another widely researched approaches in this area are related to heat therapy, such as photothermal therapy, photodynamic therapy and magnetic hyperthermia, besides molecular targeting. This review will contemplate the most relevant studies that have shown the effects of nanotherapeutics. In conclusion, although the studies analyzed are mostly preclinical, we believe that there is strong evidence that nanoparticles can increase the chances of a better prognosis to cancer in the future. It is also essential to transpose these findings to the clinic to confirm and better understand the role of nanotherapeutics in this context.

Bioinspired Microenvironment Responsive Nanoprodrug as an Efficient Hydrophobic Drug Self-Delivery System for Cancer Therapy

Artemisinin compounds have shown satisfactory safety records in anti-malarial clinical practice over decades and have revealed value as inexpensive anti-tumor adjuvant chemotherapeutic drugs. However, the rational design and precise preparation of nanomedicines based on the artemisinin drugs are still limited due to their non-aromatic and fragile chemical structure. Herein, a bioinspired coordination-driven self-assembly strategy was developed to manufacture the artemisinin-based nanoprodrug with a significantly increased drug loading efficacy (∼70 wt %) and decreased preparation complexity compared to conventional nanodrugs. The nanoprodrug has suitable size distribution and robust colloidal stability for cancer targeting in vivo. The nanoprodrug was able to quickly disassemble in the tumor microenvironment with weak acidity and a high glutathione concentration, which guarantees a better tumor inhibitory effect than direct administration and fewer side effects on normal tissues in vivo. This work highlights a new strategy to harness a robust, simplified, organic solvent-free, and highly repeatable route for nanoprodrug manufacturing, which may offer opportunities to develop cost-effective, safe, and clinically available nanomedicines.

De Novo Nano-Erythrocyte Structurally Braced by Biomimetic Au(I)-peptide Skeleton for MDM2/MDMX Predation toward Augmented Pulmonary Adenocarcinoma Immunotherapy

In nature, cells rely on a structural framework called the "cytoskeleton" to maintain their shape and polarity. Based on this, herein a new class of cell-mimicking nanomedicine using bionic skeletons constituted by the oligomeric Au(I)-peptide complex is developed. The peptide function of degrading pathological MDM2 and MDMX is used to synthesize an oligomeric Au(I)-PMIV precursor capable of self-assembling into a clustered spherical bionic skeleton. Through coating by erythrocyte membrane, an erythrocyte-mimicking nano-cell (Nery-PMIV) is developed with depressed macrophage uptakes, increased colloidal stability, and prolonged blood circulation. Nery-PMIV potently restores p53 and p73 in vitro and in vivo by degrading MDM2/MDMX. More importantly, Nery-PMIV effectively augments antitumor immunity elicited by anti-PD1 therapy in a murine orthotopic allograft model for LUAD and a humanized patient-derived xenograft (PDX) mouse model for LUAD, while maintaining a favorable safety profile. Taken together, this work not only presents evidence showing that MDM2/MDMX degradation is a potentially viable therapeutic paradigm to synergize anti-PD1 immunotherapy toward LUAD carrying wild-type p53; it also suggests that cell-mimicking nanoparticles with applicable bionic skeletons hold tremendous promise in offering new therapies to revolutionize nanomedicine in the treatment of a myriad of human diseases.

Resurrecting a p53 peptide activator - An enabling nanoengineering strategy for peptide therapeutics

Many high-affinity peptide antagonists of MDM2 and MDMX have been reported as activators of the tumor suppressor protein p53 with therapeutic potential. Unfortunately, peptide activators of p53 generally suffer poor proteolytic stability and low membrane permeability, posing a major pharmacological challenge to anticancer peptide drug development. We previously obtained several potent dodecameric peptide antagonists of MDM2 and MDMX termed PMIs, one of which, TSFAEYWALLSP, bound to MDM2 and MDMX at respective affinities of 0.49 and 2.4 nM. Here we report the development of gold nanoparticles (Np) as a membrane-traversing delivery vehicle to carry PMI for anticancer therapy. Np-PMI was substantially more active in vitro than Nutlin-3 in killing tumor cells bearing wild-type p53, and effectively inhibited tumor growth in metastasis in a mouse homograft mode of melanoma and a patient-derived xenograft model of colon cancer with a favorable safety profile. This clinically viable drug delivery strategy can be applied not only to peptide activators of p53 for cancer therapy, but also to peptide therapeutics in general aimed at targeting intracellular protein-protein interactions for disease intervention.

Bioactive Anti-inflammatory, Antibacterial, Antioxidative Silicon-Based Nanofibrous Dressing Enables Cutaneous Tumor Photothermo-Chemo Therapy and Infection-Induced Wound Healing

Traditional skin tumor surgery and chronic bacterial-infection-induced wound healing/skin regeneration is still a challenge. The ideal strategy should eliminate the tumor, enhance wound healing/skin formation, and be anti-infection. Herein, we designed a multifunctional elastomeric poly(l-lactic acid)-poly(citrate siloxane)-curcumin@polydopamine hybrid nanofibrous scaffold (denoted as PPCP matrix) for tumor-infection therapy and infection-induced wound healing. The PPCP matrix showed intrinsically multifunctional properties including antioxidative, anti-inflammatory, photothermal, antibacterial, anticancer, and angiogenesis bioactivities. The polydopamine/curcumin presented an excellent near-infrared photothermal/cancer cell toxicity capacity, respectively, which supported PPCP for synergetic skin tumor therapy and antibacterial properties in vitro/in vivo. Additionally, the PPCP nanofibrous matrix significantly promotes the adhesion and proliferation of normal skin cells and accelerates the cutaneous wound healing in normal mice and bacterial-infected mice by enhancing the early angiogenesis. The PPCP nanofibrous matrix with multifunctional bioactivities provides a competitive strategy for skin tumor and bacterial-infection-induced wound healing.

Engineering a Biodegradable Multifunctional Antibacterial Bioactive Nanosystem for Enhancing Tumor Photothermo-Chemotherapy and Bone Regeneration

The simultaneous therapy of tumors and bone defects resulting from tumor surgery is still a challenge in clinical orthopedics. Few nanomaterial systems simultaneously possess multifunctional capacities, including biodegradability, tumor treatment, and enhanced bone regeneration. Herein, we designed a biodegradable monodispersed bioactive glass nanoparticle (BGN) platform with multifunctional properties for enhanced colon cancer photothermo-chemotherapy and bone repair. The mussel-inspired surface assembly with BGN was established as a stable NIR-excited photothermal nanoplatform (BGN@PDA) for ablating tumors. BGN@PDA shows an ultrahigh anticancer drug (DOX) loading with on-demand (pH/NIR-responsive) drug release behavior and antibacterial activity for enhanced tumor chemotherapy (BGN@PDA-DOX). The growth of colon cancer cells (Hct116 cells) and cervical cancer cells (HeLa cells) was significantly inhibited in vitro, and superior local anticancer efficacy could be achieved by synergic chemo-photothermal therapy in vivo. BGN@PDA underwent a gradual degradation in vivo during 60 days and showed negligible toxic side effects. Meanwhile, BGN@PDA could positively induce the osteogenesis of osteoblasts in vitro and possess excellent in vivo bone repair ability in rat cranial defects. This work presents a distinctive strategy to design a bioactive multifunctional nanoplatform for treating tumor disease-resulted bone tissue regeneration.