Inhibition of Thioredoxin Reductase by Targeted Selenopolymeric Nanocarriers Synergizes the Therapeutic Efficacy of Doxorubicin in MCF7 Human Breast Cancer Cells

Formation and evaluation of doxorubicin and cromoglycate metal-organic framework for anti-cancer activity

AIMS

We develop and evaluate copper-based metal-organic frameworks (Cu-MOFs) incorporating cromolyn as a linker to enhance structural stability, drug delivery efficiency, and therapeutic potential, particularly for breast cancer treatment.

MATERIALS & METHODS

Two Cu-MOF formulations were synthesized: Cu-MOFs-BDC-DOX (using terephthalic acid) and Cu-MOFs-CROMO-DOX (using cromolyn as a linker). Characterization was performed using SEM/TEM for morphology, and FTIR, XRD, and TGA to confirm structural integrity. Drug encapsulation efficiency and release profiles were assessed, followed by in vitro cytotoxicity, cell migration, and colony formation assays using MDA-MB-231 breast cancer cells.

RESULTS

Both formulations demonstrated a high encapsulation efficiency (83-91%) and sustained drug release over 48 h at pH 7.4. Cu-MOFs-CROMO-DOX exhibited superior cytotoxicity with an IC50 of 0.88 ± 0.07 µM compared to 7.1 ± 0.11 µM for Cu-MOFs-BDC-DOX. Both formulations inhibit cancer cell migration and colony formation in a dose-dependent manner.

CONCLUSIONS

The Cu-MOFs-CROMO-DOX formulation demonstrated enhanced therapeutic potential, outperforming its counterpart in targeting breast cancer cells. This study highlights the promise of MOF-based nanocarriers in overcoming the limitations of conventional chemotherapy, offering a pathway to more effective and targeted cancer treatments with reduced side effects.

Unlocking the Anticancer Potential of Frankincense Essential Oils (FEOs) Through Nanotechnology: A Review

Cancer is a group of heterogeneous diseases that occur when cells in the body proliferate and divide uncontrollably. As the current treatment modalities have pros and cons, the discovery of new chemotherapeutic agents with the least side effects is one of the most investigated research areas. In this context, plant-based natural products are a rich source of drugs and have served humanity for ages. Frankincense essential oils (FEOs) are among the most promising plant-based oils in Gulf countries. In addition to their high cultural value, FEOs are also famous for their engaging biological activities, including anti-cancerous. However, the practical application of FEOs is often hindered/by their low water solubility, limited bioavailability, high volatility, and sensitivity toward heat, humidity, light, or oxygen. Thus, a significant demand for technological advancement would improve their ability to target particular cells and tissues. Nanotechnology emerged as an exciting approach in this context. Through suitable nano-formulation (functionalization or encapsulation into a nanostructure), issues arising due to solubility, targeting capability, and delivery can be controlled.

NIR-II-Responsive Versatile Nanozyme Based on H2O2 Cycling and Disrupting Cellular Redox Homeostasis for Enhanced Synergistic Cancer Therapy

Disturbing cellular redox homeostasis within malignant cells, particularly improving reactive oxygen species (ROS), is one of the effective strategies for cancer therapy. The ROS generation based on nanozymes presents a promising strategy for cancer treatment. However, the therapeutic efficacy is limited due to the insufficient catalytic activity of nanozymes or their high dependence on hydrogen peroxide (H2O2) or oxygen. Herein, we reported a nanozyme (CSA) based on well-defined CuSe hollow nanocubes (CS) uniformly covered with Ag nanoparticles (AgNPs) to disturb cellular redox homeostasis and catalyze a cascade of intracellular biochemical reactions to produce ROS for the synergistic therapy of breast cancer. In this system, CSA could interact with the thioredoxin reductase (TrxR) and deplete the tumor microenvironment-activated glutathione (GSH), disrupting the cellular antioxidant defense system and augmenting ROS generation. Besides, CSA possessed high peroxidase-mimicking activity toward H2O2, leading to the generation of various ROS including hydroxyl radical (•OH), superoxide radicals (•O2-), and singlet oxygen (1O2), facilitated by the Cu(II)/Cu(I) redox and H2O2 cycling, and plentiful catalytically active metal sites. Additionally, due to the absorption and charge separation performance of AgNPs, the CSA exhibited excellent photothermal performance in the second near-infrared (NIR-II, 1064 nm) region and enhanced the photocatalytic ROS level in cancer cells. Owing to the inhibition of TrxR activity, GSH depletion, high peroxidase-mimicking activity of CSA, and abundant ROS generation, CSA displays remarkable and specific inhibition of tumor growth.

p53 at the Crossroads between Doxorubicin-Induced Cardiotoxicity and Resistance: A Nutritional Balancing Act

Doxorubicin (DOX) is a highly effective chemotherapeutic drug, but its long-term use can cause cardiotoxicity and drug resistance. Accumulating evidence demonstrates that p53 is directly involved in DOX toxicity and resistance. One of the primary causes for DOX resistance is the mutation or inactivation of p53. Moreover, because the non-specific activation of p53 caused by DOX can kill non-cancerous cells, p53 is a popular target for reducing toxicity. However, the reduction in DOX-induced cardiotoxicity (DIC) via p53 suppression is often at odds with the antitumor advantages of p53 reactivation. Therefore, in order to increase the effectiveness of DOX, there is an urgent need to explore p53-targeted anticancer strategies owing to the complex regulatory network and polymorphisms of the p53 gene. In this review, we summarize the role and potential mechanisms of p53 in DIC and resistance. Furthermore, we focus on the advances and challenges in applying dietary nutrients, natural products, and other pharmacological strategies to overcome DOX-induced chemoresistance and cardiotoxicity. Lastly, we present potential therapeutic strategies to address key issues in order to provide new ideas for increasing the clinical use of DOX and improving its anticancer benefits.

Heparin Biofunctionalized Selenium Nanoparticles as Potential Antiangiogenic-Chemotherapeutic Agents for Targeted Doxorubicin Delivery

Combining antiangiogenic and chemotherapeutic agents has shown promising clinical benefits in cancer cures when the therapeutic intervention takes into account the tissue and molecular targets. Moreover, the risk of induced drug resistance is minimized when multiple pathways are involved in the treatment regimen, yielding a better therapeutic outcome. Nanodrug delivery systems have proven to be a prudent approach to treating complex disease pathologies. As such, combining antiangiogenic and chemotherapeutic drugs within multimodal nanocarriers synergistically augments the clinical efficiency of the drugs. This study reports the combinatorial efficacy of heparin (Hep), selenium NPs (SeNPs), and doxorubicin (Dox) to inhibit tumor growth and progression. Both Se@Hep-NPs and Se@Hep-Dox-NPs with excellent water dispersity having a size and charge in the range of 250 ± 5 and 253 ± 5 nm and -53 ± 0.4 and -48.4 ± 6.4 mV, respectively, showed strong anticancer potential assessed through in vitro assays like cell viability, specificity, colony formation, and wound scratch in MCF7 cells. Strong synergistic interactions among SeNPs, Hep, and Dox in Se@Hep-Dox-NPs render it to be an antiangiogenic and proapoptotic cancer cell death inducers. In vivo imaging highlights the dual-mode attributes of Se@Hep-NPs with desirable passive tumor targeting and biomedical imaging ability when tagged with Cy7.5, while Se@Hep-Dox-NPs significantly reduce the tumor burden and prolong the longevity of subcutaneous EAC-bearing mice. Histopathology studies reveal no signs of toxicity in major organs. Collectively, these results qualify Se@Hep-Dox-NPs as a plausible clinical therapeutic candidate.

Theranostic applications of selenium nanomedicines against lung cancer

The incidence and mortality rates of lung cancer are among the highest in the world. Traditional treatment methods include surgery, chemotherapy, and radiotherapy. Although rapid progress has been achieved in the past decade, treatment limitations remain. It is therefore imperative to identify safer and more effective therapeutic methods, and research is currently being conducted to identify more efficient and less harmful drugs. In recent years, the discovery of antitumor drugs based on the essential trace element selenium (Se) has provided good prospects for lung cancer treatments. In particular, compared to inorganic Se (Inorg-Se) and organic Se (Org-Se), Se nanomedicine (Se nanoparticles; SeNPs) shows much higher bioavailability and antioxidant activity and lower toxicity. SeNPs can also be used as a drug delivery carrier to better regulate protein and DNA biosynthesis and protein kinase C activity, thus playing a role in inhibiting cancer cell proliferation. SeNPs can also effectively activate antigen-presenting cells to stimulate cell immunity, exert regulatory effects on innate and regulatory immunity, and enhance lung cancer immunotherapy. This review summarizes the application of Se-based species and materials in lung cancer diagnosis, including fluorescence, MR, CT, photoacoustic imaging and other diagnostic methods, as well as treatments, including direct killing, radiosensitization, chemotherapeutic sensitization, photothermodynamics, and enhanced immunotherapy. In addition, the application prospects and challenges of Se-based drugs in lung cancer are examined, as well as their forecasted future clinical applications and sustainable development.

pH-Responsive Selenium Nanoplatform for Highly Efficient Cancer Starvation Therapy by Atorvastatin Delivery

Recently, starvation-inducing nutrient deprivation has been regarded as a promising strategy for tumor suppression. As a first-line lipid-lowering drug, atorvastatin (ATV) significantly reduces caloric intake, suggesting its potential in starvation therapy for suppressing tumors. Accordingly, we developed a novel starvation therapy agent (HA-Se-ATV) in this study to suppress tumor growth by using hyaluronic acid (HA)-conjugated chitosan polymer-coated nano-selenium (Se) for loading ATV. HA-Se-ATV targets cancer cells, following which it effectively accumulates in the tumor tissue. The HA-Se-ATV nanoplatform was then activated by inducing a weakly acidic tumor microenvironment and subsequently releasing ATV. ATV and Se synergistically downregulate the levels of cellular adenosine triphosphate while inhibiting the expression of thioredoxin reductase 1. Consequently, the starvation-stress reaction of cancer cells is significantly elevated, leading to cancer cell death. Furthermore, the in vivo results indicate that HA-Se-ATV effectively suppresses tumor growth with a low level of toxicity, demonstrating its great potential for clinical translation.

Targeted Delivery of Doxorubicin Using Transferrin-Conjugated Carbon Dots for Cancer Therapy

A transferrin receptor (TfR)-targeted nanodrug [green fluorescence emission carbon dot (GCD)-polyethylene glycol (PEG)-transferrin (Tf)@doxorubicin (Dox)] for cancer therapy was developed by functionalizing GCDs with PEG, Tf, and Dox. GCDs were synthesized by the one-step hydrothermal method, followed by conjugating PEG and Tf by covalent bonds and loading Dox by electrostatic interactions. The nanodrug exhibits high stability under neutral conditions and effectively releases Dox at pH of 5.5. GCD-PEG-Tf@Dox can be selectively internalized by TfR-overexpressed tumor cells (MCF-7 and K150) via receptor-mediated endocytosis and further release Dox to the nuclei. As a result, GCD-PEG-Tf@Dox exhibits significant lethality to tumor cells (MCF-7 and K150) but greatly reduced toxicity to normal cells [Chinese hamster ovary cell line (CHO)] compared with free Dox. In vivo studies have confirmed that GCD-PEG-Tf@Dox can effectively inhibit tumor proliferation with negligible side effects.

Control Release of Adenosine Potentiate Osteogenic Differentiation within a Bone Integrative EGCG-g-NOCC/Collagen Composite Scaffold toward Guided Bone Regeneration in a Critical-Sized Calvarial Defect

The regeneration of critical-sized bone defects with biomimetic scaffolds remains clinically challenging due to avascular necrosis, chronic inflammation, and altered osteogenic activity. Two confounding mechanisms, efficacy manipulation, and temporal regulation dictate the scaffold's bone regenerative ability. Equally critical is the priming of the mesenchymal stromal cells (MSCs) toward lineage-specific differentiation into bone-forming osteoblast, which particularly depends on varied mechanochemical and biological cues during bone tissue regeneration. This study sought to design and develop an optimized osteogenic scaffold, adenosine/epigallocatechin gallate-N,O-carboxymethyl chitosan/collagen type I (AD/EGCG-g-NOCC@clgn I), having osteoinductive components toward swift bone regeneration in a calvarial defect BALB/c mice model. The ex vivo findings distinctly establish the pro-osteogenic potential of adenosine and EGCG, stimulating MSCs toward osteoblast differentiation with significantly increased expression of alkaline phosphatase, calcium deposits, and enhanced osteocalcin expression. Moreover, the 3D matrix recapitulates extracellular matrix (ECM) properties, provides a favorable microenvironment, structural support against mechanical stress, and acts as a reservoir for sustained release of osteoinductive molecules for cell differentiation, proliferation, and migration during matrix osteointegration observed. Evidence from in vivo experiments, micro-CT analyses, histology, and histomorphometry signify accelerated osteogenesis both qualitatively and quantitatively: effectual bone union with enhanced bone formation and new ossified tissue in 4 mm sized defects. Our results suggest that the optimized scaffold serves as an adjuvant to guide bone tissue regeneration in critical-sized calvarial defects with promising therapeutic efficacy.

Reduction/Oxidation-Responsive Hierarchical Nanoparticles with Self-Driven Degradability for Enhanced Tumor Penetration and Precise Chemotherapy

Deep tumor penetration, long blood circulation, rapid drug release, and sufficient stability are the most concerning dilemmas of nano-drug-delivery systems for efficient chemotherapy. Herein, we develop reduction/oxidation-responsive hierarchical nanoparticles co-encapsulating paclitaxel (PTX) and pH-stimulated hyaluronidase (pSH) to surmount the sequential biological barriers for precise cancer therapy. Poly(ethylene glycol) diamine (PEG-dia) is applied to collaboratively cross-link the shell of nanoparticles self-assembled by a hyaluronic acid-stearic acid conjugate linked via a disulfide bond (HA-SS-SA, HSS) to fabricate the hierarchical nanoparticles (PHSS). The PTX and pSH coloaded hierarchical nanoparticles (PTX/pSH-PHSS) enhance the stability in normal physiological conditions and accelerate drug release at tumorous pH, and highly reductive or oxidative environments. Functionalized with PEG and HA, the hierarchical nanoparticles preferentially prolong the circulation time, accumulate at the tumor site, and enter MDA-MB-231 cells via CD44-mediated endocytosis. Within the acidic tumor micro-environment, pSH would be partially reactivated to decompose the dense tumor extracellular matrix for deep tumor penetration. Interestingly, PTX/pSH-PHSS could be degraded apace by the completely activated pSH within endo/lysosomes and the intracellular redox micro-environment to facilitate drug release to produce the highest tumor inhibition (93.71%) in breast cancer models.

Advances in controlled release pesticide formulations: Prospects to safer integrated pest management and sustainable agriculture

As the world is striving hard towards sustainable agricultural practices for a better tomorrow, one of the primary focuses is on effective pest management for enhanced crop productivity. Despite newer and potent chemicals as pesticides, there are still substantial crop losses, and if by any means this loss can be tackled; it will alleviate unwanted excessive use of chemical pesticides. Scientific surveys have already established that pesticides are not being utilized by the crops completely rather a significant amount remains unused due to various limiting factors such as leaching and bioconversion, etc., resulting in an adverse effect on human health and ecosystems. Concerted efforts from scientific diaspora toward newer and innovative strategies are already showing promise, and one such viable approach is controlled release systems (CRS) of pesticides. Moreover, to bring these smart formulations within the domain of current pesticide regulatory framework is still under debate. It is thus, paramount to discuss the pros and cons of this new technology vis-à-vis the conventional agrarian methods. This review deliberates on the developmental updates in this innovative field from the past decades and also appraises the challenges encumbered. Additionally, critical information and the foreseeable research gaps in this emerging area are highlighted.

Polymer-Assisted In Situ Synthesis of Silver Nanoparticles with Epigallocatechin Gallate (EGCG) Impregnated Wound Patch Potentiate Controlled Inflammatory Responses for Brisk Wound Healing

Introduction

An ideal wound dressing material needs to be predisposed with desirable attributes like anti-infective effect, skin hydration balance, adequate porosity and elasticity, high mechanical strength, low wound surface adherence, and enhanced tissue regeneration capability. In this work, we have synthesized hydrogel-based wound patches having antibacterial silver nanoparticles and antioxidant epigallocatechin gallate (EGCG) and showed fast wound closure through their synergistic interaction without any inherent toxicity.

Methods and results

Wound patches were synthesized from modified guar gum polymer and assessed to determine accelerated wound healing. The modified polymer beget chemical-free in-situ synthesis of monodispersed silver NPs (~12 nm), an antimicrobial agent, besides lending ionic surface charges. EGCG impregnated during ionotropic gelation process amplified the efficacy of wound patches that possess apt tensile strength, porosity, and swellability for absorbing wound exudates. Further, in vitro studies endorsed them as non-cytotoxic and the post agent effect following exposure to the patch showed an unbiased response to E coli K12 and B. subtilis. In vivo study using sub-cutaneous wounds in Wistar rats validated its accelerated healing properties when compared to a commercially available wound dressing material (skin graft; Neuskin-F^®) through better wound contraction, promoted collagen deposition and enhanced vascularization of wound region by modulating growth factors and inflammatory cytokines.

Conclusion

Synthesized wound patches showed all the desired attributes of a clinically effective dressing material and the results were validated in various in vitro and in vivo assays.

An update on the mechanisms related to cell death and toxicity of doxorubicin and the protective role of nutrients

Doxorubicin (DOX), is a very effective chemotherapeutic agent against cancer whose clinical use is limited by toxicity. Different strategies have been proposed to attenuate toxicity, including combined therapy with bioactive compounds. This review update mechanisms of action and toxicity of doxorubicin and the role of nutrients like vitamins (A, C, E), minerals (selenium) and n-3 polyunsaturated fatty acids. Protective activities against DOX toxicity in liver, kidney, skin, bone marrow, testicles or brain have been reported, but these have not been evaluated for all of the reviewed nutrients. In most cases oxidation-related effects were present either, by reducing ROS levels and/or increasing antioxidant defenses. Antiapoptotic and anti-inflammatory mechanisms are also commonly reported. In some cases, interferences with autophagy and calcium homeostasis also have shown to be affected. Notwithstanding, there is a wide variety in duration and doses of treatment tested for both, compounds and DOX, which make difficult to compare the results of the studies. In spite of the reduction of DOX cardiotoxicity in health models, DOX anti-cancer activity in cancer cell lines or xenograft models usually did not result compromised when this has been evaluated. Importantly, clinical studies are needed to confirm all the observed effects.

The role of thioredoxin system in cancer: strategy for cancer therapy

PURPOSE

Cancer, a major public health problem, exhibits significant redox alteration. Thioredoxin (Trx) system, including Trx and Trx reductase (TrxR), as well as Trx-interacting protein (TXNIP) play important roles in controlling the cellular redox balance in cancer cells. In most cancers, Trx and TrxR are usually overexpressed and TXNIP is underexpressed. In recent years, some agents targeting Trx, TrxR, and TXNIP were used to explore a therapy approach for cancer patients.

METHODS

A systematic search of PMC and the PubMed Database was conducted to summarize the potential of Trx system inhibitors for cancer treatment.

RESULTS

In this article, we first summarize the functions of Trx, TrxR, and TXNIP in cancers. We also review some small molecule inhibitors of Trx/TrxR and D-allose (TXNIP inducer) and discuss their antitumor mechanisms. We highlight the combined inhibition of Trx system and GSH system in cancer therapy. We expect that a highly specific and selective antitumor agent with no cytotoxicity on human normal cells could be developed in the future.

CONCLUSION

In conclusion, Trx system may be very promising for clinical therapy of cancer in the future.

Doxorubicin-loaded functionalized selenium nanoparticles for enhanced antitumor efficacy in cervical carcinoma therapy

Development of novel tumor-targeted drug vehicles for cancer therapy is very important and has become one of major topics for designing nanoscale chemotherapeutics delivery systems. In the present study, selenium nanoparticles (SeNPs) was decorated with hyaluronic acid (HA) to prepare HA-SeNPs nanoparticles which were used to load doxorubicin (DOX) to fabricate tumor-targeted functionalized selenium nanoparticles HA-Se@DOX. In vitro and in vivo antitumor activities of HA-Se@DOX in human cervical carcinoma treatment were investigated. HA-Se@DOX showed selective cellular uptakes between cervical cancer HeLa cells and human umbilical vein endothelial cells (HUVEC). In vitro release result indicated that DOX was released from HA-SeNPs faster in acidic environment in comparison with normal physiological environment and 76.9% DOX was released in pH 5.4 during initial 30 h. HA-Se@DOX showed high activity to inhibit HeLa cell proliferation and triggered HeLa cell apoptosis via activating Bcl-2 signaling pathway. In vivo antitumor study showed that HA-Se@DOX inhibited tumor growth through suppressing cancer cells proliferation and inducing cancer cells apoptosis. Interestingly, HA-Se@DOX exhibited stronger anticancer activity than free DOX and Se@DOX in vitro and in vivo. Additionally, HA-Se@DOX did not cause damage to major organs at the used dose. HA-Se@DOX is a promising antitumor agent for human cervical carcinoma treatment and this research provides a novel therapeutic strategy for cancer therapy.

Selenium Species: Current Status and Potentials in Cancer Prevention and Therapy

Selenium (Se) acts as an essential trace element in the human body due to its unique biological functions, particularly in the oxidation-reduction system. Although several clinical trials indicated no significant benefit of Se in preventing cancer, researchers reported that some Se species exhibit superior anticancer properties. Therefore, a reassessment of the status of Se and Se compounds is necessary in order to provide clearer insights into the potentiality of Se in cancer prevention and therapy. In this review, we organize relevant forms of Se species based on the three main categories of Se-inorganic, organic, and Se-containing nanoparticles (SeNPs)-and overview their potential functions and applications in oncology. Here, we specifically focus on the SeNPs as they have tremendous potential in oncology and other fields. In general, to make better use of Se compounds in cancer prevention and therapy, extensive further study is still required to understand the underlying mechanisms of the Se compounds.

Significance of the mitochondrial thioredoxin reductase in cancer cells: An update on role, targets and inhibitors

Thioredoxin reductase 2 (TrxR2) is a key component of the mitochondrial thioredoxin system able to transfer electrons to peroxiredoxin 3 (Prx3) in a reaction mediated by thioredoxin 2 (Trx2). In this way, both the level of hydrogen peroxide and thiol redox state are modulated. TrxR2 is often overexpressed in cancer cells conferring apoptosis resistance. Due to their exposed flexible arm containing selenocysteine, both cytosolic and mitochondrial TrxRs are inhibited by a large number of molecules. The various classes of inhibitors are listed and the molecules acting specifically on TrxR2 are extensively described. Particular emphasis is given to gold(I/III) complexes with phosphine, carbene or other ligands and to tamoxifen-like metallocifens. Also chemically unrelated organic molecules, including natural compounds and their derivatives, are taken into account. An important feature of many TrxR2 inhibitors is provided by their nature of delocalized lipophilic cations that allows their accumulation in mitochondria exploiting the organelle membrane potential. The consequences of TrxR2 inhibition are presented focusing especially on the impact on mitochondrial pathophysiology. Inhibition of TrxR2, by hindering the activity of Trx2 and Prx3, increases the mitochondrial concentration of reactive oxygen species and shifts the thiol redox state toward a more oxidized condition. This is reflected by alterations of specific targets involved in the release of pro-apoptotic factors such as cyclophilin D which acts as a regulator of the mitochondrial permeability transition pore. Therefore, the selective inhibition of TrxR2 could be utilized to induce cancer cell apoptosis.