Multistage pH-responsive codelivery liposomal platform for synergistic cancer therapy

Innovative nebulization delivery of lipid nanoparticle-encapsulated siRNA: a therapeutic advance for Staphylococcus aureus-induced pneumonia

BACKGROUND

Integrin α5β1 plays a crucial role in the invasion of nonphagocytic cells by Staphylococcus aureus (S. aureus), thereby facilitating infection development. Lipid nanoparticles (LNPs) serve as an effective vehicle for delivering small interfering ribonucleic acids (siRNA) that represent a method to knockdown integrin α5β1 in the lungs through nebulization, thereby potentially mitigating the severity of S. aureus pneumonia. The aim of this study was to harness LNP-mediated targeting to precisely knockdown integrin α5β1, thus effectively addressing S. aureus-induced pneumonia.

METHODS

C57 mice (8 week-old females) infected with S. aureus via an intratracheal nebulizing device were utilized for the experiments. The LNPs were synthesized via microfluidic mixing and characterized by their size, polydispersity index, and encapsulation efficiency. Continuous intratracheal nebulization was employed for consistent siRNA administration, with the pulmonary function metrics affirming biosafety. The therapeutic efficacy of LNP-encapsulated siRNAs against pneumonia was assessed through western blotting, bacterial count measurement, quantitative polymerase chain reaction, and histological analyses.

RESULTS

LNPs, which have an onion-like structure, retained integrity post-nebulization, ensuring prolonged siRNA stability and in vivo safety. Intratracheal nebulization delivery markedly alleviated the severity of S. aureus-induced pneumonia, as indicated by reduced bacterial load and bolstered immune response, thereby localizing the infection to the lungs and averting systemic dissemination.

CONCLUSIONS

Intratracheal nebulization of LNP-encapsulated siRNAs targeting integrin α5β1 significantly diminished the S. aureus-mediated cellular invasion and disease progression in the lungs, presenting a viable therapeutic approach for respiratory infections.

Tumor Microenvironment Responsive RNA Drug Delivery Systems: Intelligent Platforms for Sophisticated Release

Cancer is a significant health concern, increasingly showing insensitivity to traditional treatments, highlighting the urgent need for safer and more practical treatment options. Ribonucleic acid (RNA) gene therapy drugs have demonstrated promising potential in preclinical and clinical trials for antitumor therapy by regulating tumor-related gene expression. However, RNA's poor membrane permeability and stability restrict its effectiveness in entering and being utilized in cells. An appropriate delivery system is crucial for achieving targeted tumor effects. The tumor microenvironment (TME), characterized by acidity, hypoxia, enzyme overexpression, elevated glutathione (GSH) concentration, and excessive reactive oxygen species (ROS), is essential for tumor survival. Furthermore, these distinctive features can also be harnessed to develop intelligent drug delivery systems. Various nanocarriers that respond to the TME have been designed for RNA drug delivery, showing the advantages of tumor targeting and low toxicity. This Review discusses the abnormal changes of components in TME, therapeutic RNAs' roles, underlying mechanisms, and the latest developments in utilizing vectors that respond to microenvironments for treating tumors. We hope it provides insight into creating and optimizing RNA delivery vectors to improve their effectiveness.

ROS-responsive and triple-synergistic mitochondria-targeted polymer micelles for efficient induction of ICD in tumor therapeutics

Immunogenic cell death (ICD) represents a modality of apoptosis distinguished by the emanation of an array of damage-related molecular signals. This mechanism introduces a novel concept in the field of contemporary tumor immunotherapy. The inception of reactive oxygen species (ROS) within tumor cells stands as the essential prerequisite and foundation for ICD induction. The formulation of highly efficacious photodynamic therapy (PDT) nanomedicines for the successful induction of ICD is an area of significant scientific inquiry. In this work, we devised a ROS-responsive and triple-synergistic mitochondria-targeted polymer micelle (CAT/CPT-TPP/PEG-Ce6, CTC) that operates with multistage amplification of ROS to achieve the potent induction of ICD. Utilizing an "all-in-one" strategy, we direct both the PDT and chemotherapeutic units to the mitochondria. Concurrently, a multistage cyclical amplification that caused by triple synergy strategy stimulates continuous, stable, and adequate ROS generation (domino effect) within the mitochondria of cells. Conclusively, influenced by ROS, tumor cell-induced ICD is effectively activated, remodeling immunogenicity, and enhancing the therapeutic impact of PDT when synergized with chemotherapy. Empirical evidence from in vitro study substantiates that CTC micelles can efficiently provoke ICD, catalyzing CRT translocation, the liberation of HMGB1 and ATP. Furthermore, animal trials corroborate that polymer micelles, following tail vein injection, can induce ICD, accumulate effectively within tumor tissues, and markedly inhibit tumor growth subsequent to laser irradiation. Finally, transcriptome analysis was carried out to evaluate the changes in tumor genome induced by CTC micelles. This work demonstrates a novel strategy to improve combination immunotherapy using nanotechnology.

Construction Strategy of Functionalized Liposomes and Multidimensional Application

Liposomes are widely used in the biological field due to their good biocompatibility and surface modification properties. With the development of biochemistry and material science, many liposome structures and their surface functional components have been modified and optimized one by one, pushing the liposome platform from traditional to functionalized and intelligent, which will better satisfy and expand the needs of scientific research. However, a main limiting factor effecting the efficiency of liposomes is the complicated environmental conditions in the living body. Currently, in order to overcome the above problem, functionalized liposomes have become a very promising strategy. In this paper, binding strategies of liposomes with four main functional elements, namely nucleic acids, antibodies, peptides, and stimuli-responsive motif have been summarized for the first time. In addition, based on the construction characteristics of functionalized liposomes, such as drug-carrying, targeting, long-circulating, and stimulus-responsive properties, a comprehensive overview of their features and respective research progress are presented. Finally, the paper critically presents the limitations of these functionalized liposomes in the current applications and also prospectively suggests the future development directions, aiming to accelerate realization of their industrialization.

RNA-encapsulating lipid nanoparticles in cancer immunotherapy: From pre-clinical studies to clinical trials

Nanoparticle-based delivery systems such as RNA-encapsulating lipid nanoparticles (RNA LNPs) have dramatically advanced in function and capacity over the last few decades. RNA LNPs boast of a diverse array of external and core configurations that enhance targeted delivery and prolong circulatory retention, advancing therapeutic outcomes. Particularly within the realm of cancer immunotherapies, RNA LNPs are increasingly gaining prominence. Pre-clinical in vitro and in vivo studies have laid a robust foundation for new and ongoing clinical trials that are actively enrolling patients for RNA LNP cancer immunotherapy. This review explores RNA LNPs, starting from their core composition to their external membrane formulation, set against a backdrop of recent clinical breakthroughs. We further elucidate the LNP delivery avenues, broach the prevailing challenges, and contemplate the future perspectives of RNA LNP-mediated immunotherapy.

Lipid-Based Nanotechnology: Liposome

Over the past several decades, liposomes have been extensively developed and used for various clinical applications such as in pharmaceutical, cosmetic, and dietetic fields, due to its versatility, biocompatibility, and biodegradability, as well as the ability to enhance the therapeutic index of free drugs. However, some challenges remain unsolved, including liposome premature leakage, manufacturing irreproducibility, and limited translation success. This article reviews various aspects of liposomes, including its advantages, major compositions, and common preparation techniques, and discusses present U.S. FDA-approved, clinical, and preclinical liposomal nanotherapeutics for treating and preventing a variety of human diseases. In addition, we summarize the significance of and challenges in liposome-enabled nanotherapeutic development and hope it provides the fundamental knowledge and concepts about liposomes and their applications and contributions in contemporary pharmaceutical advancement.

Efficient ocular delivery of siRNA via pH-sensitive vehicles for corneal neovascularization inhibition

Corneal neovascularization (CoNV)-induced blindness is an enduring and challenging condition with limited management options. Small interfering RNA (siRNA) is a promising strategy for preventing CoNV. This study reported a new strategy using siVEGFA to silence vascular endothelial growth factor A (VEGFA) for CoNV treatment. To improve the efficacy of siVEGFA delivery, a pH-sensitive polycationic mPEG_2k-PAMA₃₀-P(DEA₂₉-D5A₂₉) (TPPA) was fabricated. TPPA/siVEGFA polyplexes enter cells via clathrin-mediated endocytosis, resulting in higher cellular uptake efficiency and comparable silencing efficiency than that of Lipofectamine 2000 in vitro. Hemolytic assays verified that TPPA safe in normal physiological environments (pH 7.4) but can easily destroy membranes in acidic mature endosomes (pH 4.0). Studies on the distribution of TPPA in vivo showed that it could prolong the retention time of siVEGFA and promote its penetration in the cornea. In a mouse model induced by alkali burn, TPPA efficiently delivered siVEGFA to the lesion site and achieved VEGFA silencing efficiency. Importantly, the inhibitory effect of TPPA/siVEGFA on CoNV was comparable to that of the anti-VEGF drug ranibizumab. Delivering siRNA using pH-sensitive polycations to the ocular environment provides a new strategy to efficiently inhibit CoNV.

Protein-based delivery systems for RNA delivery

RNA-based therapeutics have emerged as promising approaches to modulate gene expression and generate therapeutic proteins or antigens capable of inducing immune responses to treat a variety of diseases, such as infectious diseases, cancers, immunologic disorders, and genetic disorders. However, the efficient delivery of RNA molecules into cells poses significant challenges due to their large molecular weight, negative charge, and susceptibility to degradation by RNase enzymes. To overcome these obstacles, viral and non-viral vectors have been developed, including lipid nanoparticles, viral vectors, proteins, dendritic macromolecules, among others. Among these carriers, protein-based delivery systems have garnered considerable attention due to their potential to address specific issues associated with nanoparticle-based systems, such as liver accumulation and immunogenicity. This review provides an overview of currently marketed RNA drugs, underscores the significance of RNA delivery vector development, delineates the essential characteristics of an ideal RNA delivery vector, and introduces existing protein carriers for RNA delivery. By offering valuable insights, this review aims to serve as a reference for the future development of protein-based delivery vectors for RNA therapeutics.

Stimuli-responsive (nano)architectures for phytochemical delivery in cancer therapy

The use of phytochemicals for purpose of cancer therapy has been accelerated due to resistance of tumor cells to conventional chemotherapy drugs and therefore, monotherapy does not cause significant improvement in the prognosis and survival of patients. Therefore, administration of natural products alone or in combination with chemotherapy drugs due to various mechanisms of action has been suggested. However, cancer therapy using phytochemicals requires more attention because of poor bioavailability of compounds and lack of specific accumulation at tumor site. Hence, nanocarriers for specific delivery of phytochemicals in tumor therapy has been suggested. The pharmacokinetic profile of natural products and their therapeutic indices can be improved. The nanocarriers can improve potential of natural products in crossing over BBB and also, promote internalization in cancer cells through endocytosis. Moreover, (nano)platforms can deliver both natural and synthetic anti-cancer drugs in combination cancer therapy. The surface functionalization of nanostructures with ligands improves ability in internalization in tumor cells and improving cytotoxicity of natural compounds. Interestingly, stimuli-responsive nanostructures that respond to endogenous and exogenous stimuli have been employed for delivery of natural compounds in cancer therapy. The decrease in pH in tumor microenvironment causes degradation of bonds in nanostructures to release cargo and when changes in GSH levels occur, it also mediates drug release from nanocarriers. Moreover, enzymes in the tumor microenvironment such as MMP-2 can mediate drug release from nanocarriers and more progresses in targeted drug delivery obtained by application of nanoparticles that are responsive to exogenous stimulus including light.

Targeted drug delivery systems for elemene in cancer therapy: The story thus far

Elemene (ELE) is a group of broad-spectrum anticancer active ingredients with low toxicity extracted from traditional Chinese medicines (TCMs), such as Curcumae Rhizoma and Curcuma Radix, which can exert antitumour activities by regulating various signal pathways and targets. However, the strong hydrophobicity, short half-life, low bioavailability and weak in vivo targeting ability of ELE restrict its use. Targeted drug delivery systems based on nanomaterials are among the most viable methods to overcome these shortcomings. In this review, we first summarize recent studies on the clinical uses of ELE as an adjunct antitumour drug. ELE-based combination strategies have great promise for enhancing efficacy, reducing adverse reactions, and improving patients' quality of life and immune function. Second, we summarize recent studies on the antitumour mechanisms of ELE and ELE-based combination strategies. The potential mechanisms include inducing pyroptosis and ferroptosis, promoting senescence, regulating METTL3-mediated m6A modification, suppressing the Warburg effect, and inducing apoptosis and cell cycle arrest. Most importantly, we comprehensively summarize studies on the combination of targeted drug delivery systems with ELE, including passively and actively targeted drug delivery systems, stimuli-responsive drug delivery systems, and codelivery systems for ELE combined with other therapies, which have great promise in improving drug bioavailability, increasing drug targeting ability, controlling drug release, enhancing drug efficacy, reducing drug adverse effects and reversing MDR. Our summary will provide a reference for the combination of TCMs such as ELE with advanced targeted drug delivery systems in the future.

Biomimetic biomineralization nanoplatform-mediated differentiation therapy and phototherapy for cancer stem cell inhibition and antitumor immunity activation

Growing evidence suggests that the presence of cancer stem cells (CSCs) is a major challenge in current tumor treatments, especially the transition from non-CSCs to differentiation of CSCs for evading conventional therapies and driving metastasis. Here we propose a therapeutic strategy of synergistic differentiation therapy and phototherapy to induce differentiation of CSCs into mature tumor cells by differentiation inducers and synergistic elimination of them and normal cancer cells through phototherapy. In this work, we synthesized a biomimetic nanoplatform loaded with IR-780 and all-trans retinoic acid (ATRA) via biomineralization. This method can integrate aluminum ions into small-sized protein carriers to form nanoclusters, which undergo responsive degradation under acidic conditions and facilitate deep tumor penetration. With the help of CSC differentiation induced by ATRA, IR-780 inhibited the self-renewal of CSCs and cancer progression by generating hyperthermia and reactive oxygen species in a synergistic manner. Furthermore, ATRA can boost immunogenic cell death induced by phototherapy, thereby strongly causing a systemic anti-tumor immune response and efficiently eliminating CSCs and tumor cells. Taken together, this dual strategy represents a new paradigm of targeted eradication of CSCs and tumors by inducing CSC differentiation, improving photothermal therapy/photodynamic therapy and enhancing antitumor immunity.

Key Design Features of Lipid Nanoparticles and Electrostatic Charge-Based Lipid Nanoparticle Targeting

Lipid nanoparticles (LNP) have gained much attention after the approval of mRNA COVID-19 vaccines. The considerable number of currently ongoing clinical studies are testament to this fact. These efforts towards the development of LNPs warrant an insight into the fundamental developmental aspects of such systems. In this review, we discuss the key design aspects that confer efficacy to a LNP delivery system, i.e., potency, biodegradability, and immunogenicity. We also cover the underlying considerations regarding the route of administration and targeting of LNPs to hepatic and non-hepatic targets. Furthermore, since LNP efficacy is also a function of drug/nucleic acid release within endosomes, we take a holistic view of charged-based targeting approaches of LNPs not only in the context of endosomal escape but also in relation to other comparable target cell internalization strategies. Electrostatic charge-based interactions have been used in the past as a potential strategy to enhance the drug release from pH-sensitive liposomes. In this review, we cover such strategies around endosomal escape and cell internalization in low pH tumor micro-environments.

Cellular and molecular basis of therapeutic approaches to breast cancer

In recent decades, there has been a significant amount of research into breast cancer, with some important breakthroughs in the treatment of both primary and metastatic breast cancers. It's a well-known fact that treating breast cancer is still a challenging endeavour even though physicians have a fantastic toolset of the latest treatment options at their disposal. Due to limitations of current clinical treatment options, traditional chemotherapeutic drugs, and surgical options are still required to address this condition. In recent years, there have been several developments resulting in a wide range of treatment options. This review article discusses the cellular and molecular foundation of chemotherapeutic drugs, endocrine system-based treatments, biological therapies, gene therapy, and innovative techniques for treating breast cancer.

Nanoparticle drug delivery systems for synergistic delivery of tumor therapy

Nanoparticle drug delivery systems have proved anti-tumor effects; however, they are not widely used in tumor therapy due to insufficient ability to target specific sites, multidrug resistance to anti-tumor drugs, and the high toxicity of the drugs. With the development of RNAi technology, nucleic acids have been delivered to target sites to replace or correct defective genes or knock down specific genes. Also, synergistic therapeutic effects can be achieved for combined drug delivery, which is more effective for overcoming multidrug resistance of cancer cells. These combination therapies achieve better therapeutic effects than delivering nucleic acids or chemotherapeutic drugs alone, so the scope of combined drug delivery has also been expanded to three aspects: drug-drug, drug-gene, and gene-gene. This review summarizes the recent advances of nanocarriers to co-delivery agents, including i) the characterization and preparation of nanocarriers, such as lipid-based nanocarriers, polymer nanocarriers, and inorganic delivery carriers; ii) the advantages and disadvantages of synergistic delivery approaches; iii) the effectual delivery cases that are applied in the synergistic delivery systems; and iv) future perspectives in the design of nanoparticle drug delivery systems to co-deliver therapeutic agents.

Preparation of ultrasound contrast agents: The exploration of the structure-echogenicity relationship of contrast agents based on neural network model

There is a need to standardize the process of micro/nanobubble preparation to bring it closer to clinical translation. We explored a neural network-based model to predict the structure-echogenicity relationship for the preparation and fabrication of ultrasound-enhanced contrast agents. Seven formulations were screened, and 109 measurements were obtained. An artificial neural network-multilayer perceptron (ANN-MLP) model was used. The original data were divided into the training and testing groups, which included 73 and 36 groups of data, respectively. The hidden layer was selected from three hidden layers and included bias. The classification graph showed that the predicted values of the training and testing groups were 76.7% and 66.7%, respectively. According to the receiver operating characteristic curve, the accuracy of different imaging effects could achieve a prediction rate of 88.1–96.5%. The percentage graph showed that the data were gradually converging. The predictive analysis curves of different ultrasound effects gradually approached stable value of Gain. Normalized importance predicted contributions for the Pk1, poly-dispersity index (PDI), and intensity account were 100%, 98.5%, and 89.7%, respectively. The application of the ANN-MLP model is feasible and effective for the exploration of the synthesis process of ultrasound contrast agents. 1,2-Distearoyl-sn-glycero-3 phosphoethanolamine-N (methoxy[polyethylene glycol]-2000) (DSPE PEG-2000) correlated highly with the success rate of contrast agent synthesis.

CEP192 is a novel prognostic marker and correlates with the immune microenvironment in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) responds poorly to standard chemotherapy or targeted therapy; hence, exploration for novel therapeutic targets is urgently needed. CEP192 protein is indispensable for centrosome amplification, which has been extensively characterized in both hematological malignancies and solid tumors. Here, we combined bioinformatics and experimental approaches to assess the potential of CEP192 as a prognostic and therapeutic target in HCC. CEP192 expression increased with tumor stage and was associated with poor clinicopathologic features, frequent recurrence, and higher mortality. Upon single-cell RNA sequencing, CEP192 was found to be involved in the proliferation and self-renewal of hepatic progenitor-like cells. This observation was further evidenced using CEP192 silencing, which prevented tumor cell proliferation and self-renewal by arresting cells in the G0/G1 phase of the cell cycle. Notably, CEP192 was highly correlated with multiple tumor-associated cytokine ligand–receptor axes, including IL11–IL11RA, IL6–IL6R, and IL13–IL13RA1, which could promote interactions between hepatic progenitor-like cells, PLVAP+ endothelial cells, tumor-associated macrophages, and CD4+ T cells. Consequently, CEP192 expression was closely associated with an immunosuppressive tumor microenvironment and low immunophenoscores, making it a potential predictor of response to immune checkpoint inhibitors. Taken together, our results unravel a novel onco-immunological role of CEP192 in establishing the immunosuppressive tumor microenvironment and provide a novel biomarker, as well as a potential target for therapeutic intervention of HCC.