Polymeric Nanoparticles for Mitochondria Targeting Mediated Robust Cancer Therapy

Tertiary amine modification enables triterpene nanoparticles to target the mitochondria and treat glioblastoma via pyroptosis induction

Glioblastoma (GBM), the most common primary brain tumor, lacks effective treatments. Emerging evidence suggests mitochondria as a promising therapeutic target, albeit successfully targeting represents a major challenge. Recently, we discovered a group of triterpenes that can self-assemble into nanoparticles (NPs) for cancer treatment. However, unmodified triterpene NPs lack affinity for mitochondria. In this study, using oleanolic acid (OA) as an example, we demonstrated that tertiary amine modification enabled triterpene NPs to selectively target the mitochondria through interaction with translocase of outer mitochondrial membrane 70 (TOM70) leading to effective killing of GBM cells via pyroptosis. We showed that the NPs could be engineered for preferentially penetrating brain tumors through surface conjugation of iRGD, and treatment with the resulting NPs significantly prolonged the survival of tumor-bearing mice. We found that the efficacy could be further improved by encapsulating lonidamine, a mitochondrial hexokinase inhibitor. Furthermore, the observed mitochondria targeting effect through tertiary amine modification could be extended to other triterpenes, including lupeol and glycyrrhetinic acid. Collectively, this study reveals a novel strategy for targeting the mitochondria through tertiary amine modification of triterpenes, offering a promising avenue for the effective treatment of GBM.

"Actual" peptide properties required for nanoparticle development in precision cancer therapeutic delivery

Functionalizing nanoparticles with peptides (3-30 amino acids) reduces premature clearance and increases colloidal stability and targeting capacity of cancer therapeutics. Glutamate/lysine-rich zwitterionic and hydrophilic/neutral peptides minimize reticuloendothelial digestion of nanomedicine through reducing particle hydrophobicity and depressing plasma anti-PEG immunoglobulin that disrupts the PEG-based particle stealth. Anionic peptides negate protein corona formation and subsequent particle aggregation in vivo enabling efficient nanoparticles biodistribution and drug targeting by facilitating their endothelial/extracellular matrix pore diffusion. Cationic and hydrophobic peptides display a strong affinity for anionic cancer cell membrane and mediate membrane porosification or receptor binding leading to particle uptake and endocytosis. The peptide ionic and hydrophobicity/hydrophilicity attributes collectively facilitate endosomal escape, and nuclear and mitochondria targeting of nanoparticles. Peptides are required to present with different physicochemical attributes from administration site, through blood and extracellular matrix, to cancer site of action. Charge/hydrophilicity-hydrophobicity switching and projection of receptor-specific domain of peptides are attainable through pH-pKa interplay and labile bond hydrolysis of "unwanted" domain to give rise to new functional domains in response to pH, thermal and enzymatic stimuli. Co-introducing all functional attributes on a single peptide is challenging. Use of peptide blends risks leaching during nanoparticles production. Peptides-nanoparticles conjugation risks peptide conformational alterations and loss of acidic/basic termini affecting their roles in nanoparticle stabilization, targeting, membrane permeabilization and subcellular delivery.

An Iron Balance Dual-Drive Strategy (IBDS) Promotes Bone Regeneration in Smokers by Regulating Mitochondrial Iron Homeostasis

Cigarette smoke (CS) disrupts mitochondrial iron homeostasis, causing excess free iron to generate reactive oxygen species, leading to oxidative stress and impairing tissue repair. For smokers undergoing bone defect repair, achieving precise control over the balance between mitochondrial free iron and stored iron, while simultaneously enhancing endogenous iron homeostasis, poses a considerable challenge. This study introduces the iron balance dual-drive strategy (IBDS), which efficiently chelates mitochondrial free iron and promotes ferritin synthesis to create a FerritinBank for iron deposition, thus optimizing endogenous iron homeostasis. IBDS is delivered through an injectable, biodegradable iron-capturing hydrogel (SilMA/gelMA/DPT). The released DPT selectively targets and chelates free iron within mitochondria, modulating mitochondrial dynamics to restore their function. This action is complemented by the promotion of ferritin synthesis, which serves to bolster endogenous iron homeostasis and suppress ferroptosis. Transcriptomic sequencing and experimental data suggest that DPT corrects energy metabolism abnormalities and promotes mitochondrial macromolecule synthesis. In vivo studies confirm that the iron-capturing hydrogel significantly improves the healing of smoking-induced calvarial bone defects. This is the first report of nanoparticles promoting ferritin synthesis to build an endogenous iron reservoir, highlighting the potential of the IBDS strategy for bone regeneration in smokers and other iron-overload-related conditions.

Recent Updates on the Efficacy of Mitocans in Photo/Radio-therapy for Targeting Metabolism in Chemo/Radio-resistant Cancers: Nanotherapeutics

Conventional therapeutic modalities against the cancers such as surgery, chemotherapy (CT) and radiotherapy (RT) have limited efficacy due to drug resistance, and adverse effects. Recent developments in nanoscience emphasized novel approaches to overcome the aforementioned limitations and subsequently improve overall clinical outcomes in cancer patients. Photodynamic therapy (PDT), photothermal therapy (PTT), and radiodynamic therapy (RDT) can be used as cancer treatments due to their high selectivity, low drug resistance, and low toxicity. Mitocans are the therapeutic molecules that can produce anti-cancer effects by modulating mitochondria functions and they have significant implications in cancer therapy. Mitochondria- targeted therapy is a promising strategy in cancer treatment as these organelles play a crucial function in the regulation of apoptosis and metabolism in tumor cells and are more vulnerable to hyperthermia and oxidative damage. The aim of this review is used to explore the targeting efficacy of mitocans in the nanotherapeutic formulation when combined with therapies like PDT, PTT, RDT. We searched several databases include Pubmed, relemed, scopus, google scholar, Embase and collected the related information to the efficacy of mitocans in nanotherapeutics when combined with photo-radiotherapy to target chemo/radio-resisant tumor cells. In this review, we vividly described research reports pertinent to the selective delivery of chemotherapy molecules into specific sub-organelles which can significantly improve the efficiency of cancer treatment by targeting tumor cell metabolism. Furthermore, the rational design, functionalization and application of various mitochondrial targeting units, including organic phosphine/sulfur salts, quaternary ammonium salts, transition metal complexes, and mitochondria-targeted cancer therapy such as PDT, PTT, RDT, and others were summarized. Mainly, the efficacy of these modalities against mtDNA and additional nanotherapeutic strategies with photosensitizers, or radiotherapy to target mitochondrial metabolism in tumor cells with chemo/radio-resistance were delineated. This review can benefit nanotechnologists, oncologists, and radiation oncologists to develop rational designs and application of novel mitochondrial targeting drugs mainly to target metabolism in chemo/radio-resistant cancer cells in cancer therapy.

Advancements in mitochondrial-targeted nanotherapeutics: overcoming biological obstacles and optimizing drug delivery

In recent decades, nanotechnology has significantly advanced drug delivery systems, particularly in targeting subcellular organelles, thus opening new avenues for disease treatment. Mitochondria, critical for cellular energy and health, when dysfunctional, contribute to cancer, neurodegenerative diseases, and metabolic disorders. This has propelled the development of nanomedicines aimed at precise mitochondrial targeting to modulate their function, marking a research hotspot. This review delves into the recent advancements in mitochondrial-targeted nanotherapeutics, with a comprehensive focus on targeting strategies, nanocarrier designs, and their therapeutic applications. It emphasizes nanotechnology's role in enhancing drug delivery by overcoming biological barriers and optimizing drug design for specific mitochondrial targeting. Strategies exploiting mitochondrial membrane potential differences and specific targeting ligands improve the delivery and mitochondrial accumulation of nanomedicines. The use of diverse nanocarriers, including liposomes, polymer nanoparticles, and inorganic nanoparticles, tailored for effective mitochondrial targeting, shows promise in anti-tumor and neurodegenerative treatments. The review addresses the challenges and future directions in mitochondrial targeting nanotherapy, highlighting the need for precision, reduced toxicity, and clinical validation. Mitochondrial targeting nanotherapy stands at the forefront of therapeutic strategies, offering innovative treatment perspectives. Ongoing innovation and research are crucial for developing more precise and effective treatment modalities.

Mitochondrial transplantation: a promising strategy for treating degenerative joint diseases

The prevalence of age-related degenerative joint diseases, particularly intervertebral disc degeneration and osteoarthritis, is increasing, thereby posing significant challenges for the elderly population. Mitochondrial dysfunction is a critical factor in the etiology and progression of these disorders. Therapeutic interventions that incorporate mitochondrial transplantation exhibit considerable promise by increasing mitochondrial numbers and improving their functionality. Existing evidence suggests that exogenous mitochondrial therapy improves clinical outcomes for patients with degenerative joint diseases. This review elucidates the mitochondrial abnormalities associated with degenerative joint diseases and examines the mechanisms of mitochondrial intercellular transfer and artificial mitochondrial transplantation. Furthermore, therapeutic strategies for mitochondrial transplantation in degenerative joint diseases are synthesized, and the concept of engineered mitochondrial transplantation is proposed.

Chitosan nanocomposite for tissue engineering and regenerative medicine: A review

Regenerative medicine and tissue engineering have emerged as a multidisciplinary promising field in the quest to address the limitations of traditional medical approaches. One of the key aspects of these fields is the development of such types of biomaterials that can mimic the extracellular matrix and provide a conducive environment for tissue regeneration. In this regard, chitosan has played a vital role which is a naturally derived linear bi-poly-aminosaccharide, and has gained significant attention due to its biocompatibility and unique properties. Chitosan possesses many unique physicochemical properties, making it a significant polysaccharide for different applications such as agriculture, nutraceutical, biomedical, food, nutraceutical, packaging, etc. as well as significant material for developing next-generation hydrogel and bio-scaffolds for regenerative medicinal applications. Moreover, chitosan can be easily modified to incorporate desirable properties, such as improved mechanical strength, enhanced biodegradability, and controlled release of bioactive molecules. Blending chitosan with other polymers or incorporating nanoparticles into its matrix further expands its potential in tissue engineering applications. This review summarizes the most recent studies of the last 10 years based on chitosan, blends, and nanocomposites and their application in bone tissue engineering, hard tissue engineering, dental implants, dental tissue engineering, dental fillers, and cartilage tissue engineering.

Biodistribution and toxicity assessment of methoxyphenyl phosphonium carbosilane dendrimers in 2D and 3D cell cultures of human cancer cells and zebrafish embryos

The consideration of human and environmental exposure to dendrimers, including cytotoxicity, acute toxicity, and cell and tissue accumulation, is essential due to their significant potential for various biomedical applications. This study aimed to evaluate the biodistribution and toxicity of a novel methoxyphenyl phosphonium carbosilane dendrimer, a potential mitochondria-targeting vector for cancer therapeutics, in 2D and 3D cancer cell cultures and zebrafish embryos. We assessed its cytotoxicity (via MTT, ATP, and Spheroid growth inhibition assays) and cellular biodistribution. The dendrimer cytotoxicity was higher in cancer cells, likely due to its specific targeting to the mitochondrial compartment. In vivo studies using zebrafish demonstrated dendrimer distribution within the vascular and gastrointestinal systems, indicating a biodistribution profile that may be beneficial for systemic therapeutic delivery strategies. The methoxyphenyl phosphonium carbosilane dendrimer shows promise for applications in cancer cell delivery, but additional studies are required to confirm these findings using alternative labelling methods and more physiologically relevant models. Our results contribute to the growing body of evidence supporting the potential of carbosilane dendrimers as vectors for cancer therapeutics.

Mitochondrial Metabolism: A New Dimension of Personalized Oncology

Energy is needed by cancer cells to stay alive and communicate with their surroundings. The primary organelles for cellular metabolism and energy synthesis are mitochondria. Researchers recently proved that cancer cells can steal immune cells' mitochondria using nanoscale tubes. This finding demonstrates the dependence of cancer cells on normal cells for their living and function. It also denotes the importance of mitochondria in cancer cells' biology. Emerging evidence has demonstrated how mitochondria are essential for cancer cells to survive in the harsh tumor microenvironments, evade the immune system, obtain more aggressive features, and resist treatments. For instance, functional mitochondria can improve cancer resistance against radiotherapy by scavenging the released reactive oxygen species. Therefore, targeting mitochondria can potentially enhance oncological outcomes, according to this notion. The tumors' responses to anticancer treatments vary, ranging from a complete response to even cancer progression during treatment. Therefore, personalized cancer treatment is of crucial importance. So far, personalized cancer treatment has been based on genomic analysis. Evidence shows that tumors with high mitochondrial content are more resistant to treatment. This paper illustrates how mitochondrial metabolism can participate in cancer resistance to chemotherapy, immunotherapy, and radiotherapy. Pretreatment evaluation of mitochondrial metabolism can provide additional information to genomic analysis and can help to improve personalized oncological treatments. This article outlines the importance of mitochondrial metabolism in cancer biology and personalized treatments.

Drug-Induced Thrombocytopenia Due to Nintedanib during Treatment of Idiopathic Pulmonary Fibrosis

Nintedanib is a tyrosine kinase inhibitor that was approved for the treatment of patients with idiopathic pulmonary fibrosis in 2014. The most common side effect of Nintedanib is diarrhea, and thrombocytopenia is a rare side effect of Nintedanib. The exact mechanism is unknown, and the literature lacks case reports of this phenomenon. Here, we report the case of a patient who developed thrombocytopenia 12 weeks after starting treatment with Nintedanib. The patient underwent an extensive work up for infectious, hematological, autoimmune, and neoplastic diseases. The patient's thrombocytopenia resolved following cessation of Nintedanib. This case is significant as it reports a rare side effect that might have detrimental consequences if not recognized and treated timely. Additionally, the onset of thrombocytopenia was delayed, 3 months after the initiation of Nintedanib. We also highlight the various literature regarding drug-induced thrombocytopenia and explore the necessary work-up needed to exclude other potential diagnoses. We hope to advocate for multidisciplinary teams to be aware of patients with pulmonary fibrosis on Nintedanib so that this adverse effect can be recognized promptly.

Biomedical applications of biodegradable polycaprolactone-functionalized magnetic iron oxides nanoparticles and their polymer nanocomposites

Magnetic nanoparticles (MNPs) have gained significant attention among several nanoscale materials during the last decade due to their unique properties. These properties make them successful nanofillers for drug delivery and a number of new biomedical applications. MNPs are more useful when combined with biodegradable polymers. In this review, we discussed the synthesis of polycaprolactones (PCL) and the various methods of synthesizing magnetic iron oxide nanoparticles. Then, the synthesis of composites that is made of PCL and magnetic materials (with special focus on iron oxide nanoparticles) were highlighted. In addition, we comprehensively reviewed their application in drug delivery, cancer treatment, wound healing, hyperthermia, and bone tissue engineering. Other biomedical applications of the magnetic PCL such as mitochondria targeting are highlighted. Moreover, biomedical applications of magnetic nanoparticles incorporated into other synthetic polymers apart from PCL are also discussed. Thus, great progress and better outcome with functionalized MNPs enhanced with polycaprolactone has been recorded with the biomedical applications of drug delivery and recovery of bone tissues.

Mitochondrial-targeted nanoparticles: Delivery and therapeutic agents in cancer

Mitochondria are the powerhouses of cells and modulate the essential metabolic functions required for cellular survival. Various mitochondrial pathways, such as oxidative phosphorylation or production of reactive oxygen species (ROS) are dysregulated during cancer growth and development, rendering them attractive targets against cancer. Thus, the delivery of antitumor agents to mitochondria has emerged as a potential approach for treating cancer. Recent advances in nanotechnology have provided innovative solutions for overcoming the physical barriers posed by the structure of mitochondrial organelles, and have enabled the development of efficient mitochondrial nanoplatforms. In this review, we examine the importance of mitochondria during neoplastic development, explore the most recent smart designs of nano-based systems aimed at targeting mitochondria, and highlight key mitochondrial pathways in cancer cells.

Hyaluronic Acid-Coated Chitosan Nanoparticles as an Active Targeted Carrier of Alpha Mangostin for Breast Cancer Cells

Alpha mangostin (AM) has potential anticancer properties for breast cancer. This study aims to assess the potential of chitosan nanoparticles coated with hyaluronic acid for the targeted delivery of AM (AM-CS/HA) against MCF-7 breast cancer cells. AM-CS/HA showed a spherical shape with an average diameter of 304 nm, a polydispersity index of 0.3, and a negative charge of 24.43 mV. High encapsulation efficiency (90%) and drug loading (8.5%) were achieved. AM released from AM-CS/HA at an acidic pH of 5.5 was higher than the physiological pH of 7.4 and showed sustained release. The cytotoxic effect of AM-CS/HA (IC₅₀ 4.37 µg/mL) on MCF-7 was significantly higher than AM nanoparticles without HA coating (AM-CS) (IC₅₀ 4.48 µg/mL) and AM (IC₅₀ 5.27 µg/mL). These findings suggest that AM-CS/HA enhances AM cytotoxicity and has potential applications for breast cancer therapy.

Delivery Systems for Mitochondrial Gene Therapy: A Review

Mitochondria are membrane-bound cellular organelles of high relevance responsible for the chemical energy production used in most of the biochemical reactions of cells. Mitochondria have their own genome, the mitochondrial DNA (mtDNA). Inherited solely from the mother, this genome is quite susceptible to mutations, mainly due to the absence of an effective repair system. Mutations in mtDNA are associated with endocrine, metabolic, neurodegenerative diseases, and even cancer. Currently, therapeutic approaches are based on the administration of a set of drugs to alleviate the symptoms of patients suffering from mitochondrial pathologies. Mitochondrial gene therapy emerges as a promising strategy as it deeply focuses on the cause of mitochondrial disorder. The development of suitable mtDNA-based delivery systems to target and transfect mammalian mitochondria represents an exciting field of research, leading to progress in the challenging task of restoring mitochondria's normal function. This review gathers relevant knowledge on the composition, targeting performance, or release profile of such nanosystems, offering researchers valuable conceptual approaches to follow in their quest for the most suitable vectors to turn mitochondrial gene therapy clinically feasible. Future studies should consider the optimization of mitochondrial genes' encapsulation, targeting ability, and transfection to mitochondria. Expectedly, this effort will bring bright results, contributing to important hallmarks in mitochondrial gene therapy.

A Cascade Targeted and Mitochondrion-Dysfunctional Nanomedicine Capable of Overcoming Drug Resistance in Hepatocellular Carcinoma

Chemoresistance is a formidable issue in clinical anticancer therapy and is pertinent to the lowered efficacies of chemotherapeutics and the activated tumor self-repairing proceedings. Herein, bifunctional amphiphiles containing galactose ligands and high-density disulfide are synthesized for encapsulating mitochondrion-targeting tetravalent platinum prodrugs to construct a cascade targeted and mitochondrion-dysfunctional nanomedicine (Gal-NP@TPt). Subsequent investigations verify that Gal-NP@TPt with sequential targeting functions toward tumors and mitochondria improved the spatiotemporal level of platinum. In addition, glutathione depletion by Gal-NP@TPt appear to substantially inhibit the proceedings of platinum detoxification, inducing the susceptibility to the mitochondrial platinum. Moreover, the strategic transportation of platinum to mitochondria lacking DNA repair machinery by Gal-NP@TPt lowers the possibility of platinum deactivation. Eventually, Gal-NP@TPt demonstrates appreciable antitumor effects for the systemic treatment of patient-derived tumor xenografts of hepatocellular carcinoma. Note that these strategies in overcoming drug resistance have also been confirmed to be valid based on genome-wide analysis via RNA-sequencing. Therefore, an intriguing multifunctional nanomedicine capable of resolving formidable chemoresistance is achieved, which should be greatly emphasized in practical applications for the treatment of intractable tumors.

Peptides vs. Polymers: Searching for the Most Efficient Delivery System for Mitochondrial Gene Therapy

Together with the nucleus, the mitochondrion has its own genome. Mutations in mitochondrial DNA are responsible for a variety of disorders, including neurodegenerative diseases and cancer. Current therapeutic approaches are not effective. In this sense, mitochondrial gene therapy emerges as a valuable and promising therapeutic tool. To accomplish this goal, the design/development of a mitochondrial-specific gene delivery system is imperative. In this work, we explored the ability of novel polymer- and peptide-based systems for mitochondrial targeting, gene delivery, and protein expression, performing a comparison between them to reveal the most adequate system for mitochondrial gene therapy. Therefore, we synthesized a novel mitochondria-targeting polymer (polyethylenimine-dequalinium) to load and complex a mitochondrial-gene-based plasmid. The polymeric complexes exhibited physicochemical properties and cytotoxic profiles dependent on the nitrogen-to-phosphate-group ratio (N/P). A fluorescence confocal microscopy study revealed the mitochondrial targeting specificity of polymeric complexes. Moreover, transfection mediated by polymer and peptide delivery systems led to gene expression in mitochondria. Additionally, the mitochondrial protein was produced. A comparative study between polymeric and peptide/plasmid DNA complexes showed the great capacity of peptides to complex pDNA at lower N/P ratios, forming smaller particles bearing a positive charge, with repercussions on their capacity for cellular transfection, mitochondria targeting and, ultimately, gene delivery and protein expression. This report is a significant contribution to the implementation of mitochondrial gene therapy, instigating further research on the development of peptide-based delivery systems towards clinical translation.