Targeted delivery of quercetin via pH-responsive zinc oxide nanoparticles for breast cancer therapy

Quercetin and Nano-Derivatives: Potential and Challenges in Cancer Therapy

Quercetin, a prevalent flavonol compound, has gained attention for its multifaceted mechanisms of action against various cancers, highlighting its potential as an adjunctive therapy in cancer treatments. This review aims to systematically evaluate the structural optimization, mechanisms of action, and clinical applications of quercetin and its nano-derivatives in cancer treatment. Employing a bibliometric analysis of 6231 articles from the Web of Science Core Collection, we observed a notable increase in annual publications, particularly from the USA and China, indicating a growing interest in quercetin's therapeutic potential. Our findings reveal that quercetin enhances the efficacy of conventional therapies by modulating critical signaling pathways, thereby increasing cancer cell sensitivity while simultaneously protecting normal tissues from therapy-induced damage. Structural modifications, including glycosylation, methylation, sulfation, and glucuronidation, alongside nanoparticle formulation, significantly improve the stability, solubility, and bioavailability of quercetin, enabling targeted drug delivery. Despite the promising preclinical outcomes, the clinical translation of quercetin remains nascent, necessitating further rigorous research to validate its safety and efficacy in human subjects. In conclusion, while quercetin exhibits substantial anticancer properties and therapeutic potential, future studies should focus on expanding sample sizes, elucidating metabolic pathways, and conducting comprehensive clinical trials to inform its application in oncology.

Therapeutic applications of quercetin-metallic complexes: a review

Flavonoids, especially quercetin, are widely recognized for their antioxidant, anti-inflammatory, anti-microbial, anti-diabetic, and anti-tumor properties, but their clinical application is limited by poor permeability. Different techniques of permeability enhancement of quercetin, i.e., preparation of phytosomes, conjugation with glucose, and interaction of piperine, are reported extensively, but formation of metal complexes is considered more precise and reliable. This review focuses on research conducted on the chelation of quercetin with metals, i.e., copper (II), zinc (II), iron and ruthenium. In-vitro and in-vivo therapeutic activities, biomedical applications of metal/quercetin inclusion complexes and discussions of stability concerns of quercetin alone and its metallic complexes. Conjugation of metals with quercetin augments its potential to the next level. Numerous studies revealed that quercetin/copper (Q/Cu) and quercetin/zinc (Q/Zn) can become efficacious candidates in acute myeloid leukaemia, orthopaedics and severe acute respiratory syndrome coronavirus (SARS-CoV) infection.

Quercetin-loaded magnetic nanoparticles: a promising tool for antitumor treatment in human breast cancer cells

Quercetin (QUE) is a phytoestrogen with known antitumor properties; however, its hydrophobic nature and low bioavailability limit its efficacy as an anticancer drug. To address this, we explored loading QUE onto a non-toxic nanocarrier. This study focused on the biological activity of magnetic iron oxide nanoparticles coated with polyethylene glycol (MAG@PEG) loaded with QUE (MAG@PEG@QUE) in MCF-7 cells. The MAG@PEG nanosystem was synthesised using a hydrothermal method, and QUE was incorporated by adding an alcoholic solution of QUE to an aqueous dispersion of MAG@PEG. QUE incorporation was confirmed qualitatively by FTIR spectroscopy and quantitatively through UV-visible spectroscopy. Cytotoxicity studies showed that MAG@PEG@QUE, at a concentration equivalent to the half-maximal inhibitory concentration (IC50) of free QUE, significantly reduced cell proliferation and viability while increasing apoptosis. MCF-7 cells treated with MAG@PEG@QUE also displayed actin cytoskeleton alterations typical of apoptotic cells. Transmission electron microscopy revealed clusters of magnetic nanoparticles within cellular vesicles. Targeted delivery of these nanoparticles was achieved using a static magnetic field, leading to high intracellular accumulation and selective cell death in targeted areas, without affecting adjacent cells. In conclusion, MAG@PEG@QUE shows comparable antitumor effects to free QUE and has the potential to enhance QUE's bioavailability and targeted delivery for breast cancer treatment.

"Harnessing green synthesized zinc oxide nanoparticles for dual action in wound management: Antibiotic delivery and healing Promotion"

Wound infections are characterized by the invasion of microorganisms into bodily tissues, leading to inflammation and potentially affecting any type of wound, including surgical incisions and chronic ulcers. If left untreated, they can delay recovery and cause tissue damage. Healthcare providers face challenges in treating these infections, which necessitate efficient treatment plans involving microbiological testing and clinical evaluation. The effectiveness of conventional treatments like antibiotics is limited by resistance. Various forms of nanotechnology have been developed, each exhibiting unique properties that address particular issues with conventional therapies. Among all the Nanocarriers, zinc oxide nanoparticles (ZnO NPs), offer promising treatments for persistent wound infections. ZnO NPs possess strong antibacterial, antioxidant, anti-inflammatory, and anti-diabetic properties, making them suitable for wound care applications. These nanoparticles can be produced economically and environmentally using green synthesis techniques that minimize toxicity and are biocompatible. While chemical and physical techniques offer precise control over nanoparticle characteristics, they often involve hazardous substances and energy-intensive procedures. The antibacterial qualities, low toxicity, and biological compatibility of green-synthesized ZnO NPs make them a promising treatment for wound infections. Their use in scaffolds, drug delivery systems, and wound dressings provides a viable approach to combat antibiotic resistance and enhance wound treatment outcomes. Furthermore research is necessary to fully realize the benefits of ZnO NPs in clinical practice.

Double-Layer Microneedle Patch Loaded with HA-PBA-QCT for Management of Paclitaxel-Induced Peripheral Neuropathic Pain

Chemotherapy-induced neuropathic pain (CINP) is a common adverse effect of antineoplastic drugs, often leading to dose reduction, treatment delays, or cessation of chemotherapy. Chemotherapy agents, like paclitaxel (PTX), damage the somatosensory nervous system by inducing neuroinflammation and oxidative stress, resulting in the sensitization of sensory neurons. Quercetin (QCT), known for its anti-inflammatory, antioxidant, and neuroprotective properties, is investigated for various neurological disorders. This work creates phenylboronic acid-modified hyaluronic acid (HA-PBA) gels with incorporated QCT and fabricates a double-layer microneedle (MN) patch using an HA-PBA-QCT complex in the needles and HA/polyvinyl alcohol (PVA) as the substrate. The crosslinking between PVA and HA-PBA-QCT enables a controlled, sustained release of QCT upon application. This work applies these QCT-loaded microneedle (QMN) patches to the instep skin of PTX-treated mice, which exhibits mechanical allodynia and cold hyperalgesia. Biweekly applications of the QMN patches significantly reduce pain responses. This analgesic effect is associated with the modulation of satellite glial cell activity, decreased macrophage infiltration, and reduced TNF-α and IL-6 levels in dorsal root ganglia (DRGs). Additionally, the treatment improves cellular antioxidant capacity, indicated by upregulated Nrf2 and catalase in DRGs. Overall, these findings suggest that double-layer QMN patches offer long-term anti-inflammatory and antioxidant benefits, potentially alleviating CINP in patients.

A Systematic Review and Meta-Analysis of the Metal Nano-Particles Loaded with Herbal Drugs Moieties Against Breast Cancer

BACKGROUND

Breast cancer is the most prevalent cancer among women. About 685K deaths were globally listed in 2020 by the World Health Organization. Nowadays, scientists prefer to use herbal medicines due to their low toxicity. Herbal medicines are used to overcome the toxicity effects of surgical removal, radio-chemo therapy and medication, which have a lot of risk of damaging the healthy tissues. To overcome this, enhance bioavailability and target specify, nano-formulation chemotherapy was introduced using herbal moiety for anticancer activity. The use of metallic nanoparticles (MNPs), particularly those made of silver, cobalt, zinc, and gold as contrast, antibacterial, anticancer, and drug delivery agents has revolutionised the medicinal field. Although MNPs can be made via exacting physical and chemical processes, a biological method utilising natural materials has been established recently.

OBJECTIVES

This patent review article will offer a succinct explanation of the use of MNPs and its potential impact on herbal medicines in the future.

METHODS

Using PRISMA principles, this review systematically examines studies that concentrate on metal nanoparticles loaded with herbal compounds for the treatment of breast cancer. Various Databases were studied: PubMed, Elsevier, ScienceDirect, SpringerLink, Taylor & Francis Online, ACS Publications, Publishing Royal Society of Chemistry, and Future Medicines. Studies were selected if they were peer-reviewed primary studies published in the past 10 years.

RESULTS

We found that many herbal nano-formulations are more effective in breast cancer treatment than other types of formulations. Efficacy, safety and drug stability are also enhanced using nanoformulations.

CONCLUSION

Nano-formulation is found to be more effective in the treatment of breast cancer.

Quercetin and microRNA Interplay in Apoptosis Regulation: A New Therapeutic Strategy for Cancer?

Cancer is known as a global problem for the health and economy. Following cancer onset, apoptosis is the primary mechanism countering the tumor cells' growth. Most anticancer agents initiate apoptosis to remove tumor cells. Phytochemicals have appeared as a beneficial treatment option according to their less adverse effects. In recent decades, quercetin has been highlighted due to its high pharmacological benefits, and various literature has suggested it as a potential anti-proliferative agent against different kinds of cancers. The microRNAs (miRNAs) play key roles in cancer treatment, progression, and apoptosis. This review reviewed the effect of quercetin on miRNAs contributing to the induction or inhibition of apoptosis in cancers.

Gold nanoparticle encapsulated hybrid MOF: synthesis, characterization, and co-drug delivery of 5-fluorouracil and curcumin

The unique features of Metal-Organic Frameworks (MOFs), including structural flexibility, high surface area, and variable pore size, have drawn attention in cancer therapy. However, despite advances in surface functionalization, engineering structural features, and porosity, achieving controlled release, stability, scalability, and toxicity remains a challenge. The current study reports gold nanoparticle (AuNP) encapsulated dual metal-organic frameworks (MOFs) comprising zeolitic imidazolate (ZIF8) and cobalt-imidazole (ZIF67) by a simple precipitation method for dual drug delivery applications. This combination associates the advantages of AuNPs and MOFs, creating a potent platform for cancer theranostics that combines diagnosis and treatment into one unit. The synthesized composite (AuNPs@ZIF-8/ZIF-67) is functionalized with Folic acid (FA) and loaded with the anticancer agents Curcumin (C) and 5-fluorouracil (5-FU) for co-drug delivery The synthesized composites, namely Au/ZIF8, Au/ZIF8/ZIF67/FA, Au/ZIF8/ZIF67/FA/5-FU, and Au/ZIF8/ZIF67/FA/5-FU/C were characterized using diverse analytical techniques such as FESEM, XRD, FTIR, TEM, and BET. The characterization methods showed that the hybrid MOF structure was stable and intact after AuNP encapsulation and drug loading. The dual MOF composite exhibits a better affinity for loading C and 5-FU with 60% and 40% drug loading capacity, respectively. The simultaneous drug release studies suggest that AuNPs@ZIF-8/ZIF-67 are more responsive to the acidic pH and show a higher cumulative drug release of 5FU and C at the lower value of pH 5. For further validation, the release kinetics data were fitted into the Korsmeyer-Peppas model in the current study. The observed value of n which is less than 0.5 suggests the pseudo-Fickian diffusion mechanism for drug release, demonstrating long-term release of 5FU and C from Au/ZIF8/ZIF67/FA/5-FU/C. The targeted drug delivery system is anticipated to display synergistic therapeutic efficacy from the combined effect of the two anticancer agents and the pH-responsive nature of ZIF systems.

Modulation of miR-205 expression using a Cheiranthus cheiri phyto-nano hybrid as a potential therapeutic agent against breast cancer

Breast cancer is the fifth major cause of fatalities associated with cancer worldwide and in Pakistan, 34 066 female breast cancer cases were recorded in 2018. This study was designed to understand extracts of Cheiranthus cheiri (C. cheiri) and to evaluate the epigenetic modulation of microRNA expression for breast cancer therapy using a selected phyto-nanohybrid treatment. The phytochemical screening revealed the presence of potential phytochemicals and antioxidant scavenging activity in the C. cheiri extracts with a DPPH (2-diphenyl-1-picryl-hydroxyl) assay giving an IC50 value of 20.63 μg mL-1. GC-MS (gas chromatography-mass spectroscopy) analysis of the C. cheiri n-hexane extract detected 42 phytocompounds. Titanium oxide (TiO2) nanoparticles were synthesized and characterized using XRD (X-ray diffraction), SEM (scanning electron microscopy) and EDX (energy dispersive X-ray spectrometry) to confirm the synthesis of anatase (tetragonal) TiO2. The prepared nanoparticles were conjugated with the selected plant i.e., C. cheiri. The resulting phyto-nanohybrid was used for the subsequent treatment of breast cancer induced in a female rat model. The treatment groups were as follows: doxorubicin as the standard treatment, C. cheiri, TiO2 and the phyto-nano hybrid treatment. After 8 weeks of treatment, the groups induced to exhibit breast cancer (with and without treatment) and the control groups were dissected and analysed for histopathological, haematological and microRNA expression. Histopathological examination revealed chronic inflammation in the dilated ducts and tumour embolus formation, thus confirming the presence of breast cancer in the DMBA-induced female rat model. MicroRNA expression analysis showed a statistically significant decrease in levels of miR-205 in the plasma of the breast cancer rat model compared to the control (p < 0.05). After treatment with the phyto-nano hybrid, a statistically significant increase in the expression of miR-205 was observed in the rat models induced to exhibit breast cancer compared to the rat model without any treatment (p < 0.05). The downregulation of miR-205 in the plasma of the breast cancer exhibiting model, as compared to the control, and its upregulation after treatment with the selected phyto-nano hybrid indicated its diagnostic and prognostic significance. It is concluded that the phyto-nano hybrid used in this study is effective against breast cancer induced female rat model. All the results support the finding that the selected phyto-nano hybrid has great potential as a possible therapeutic agent for the treatment of breast cancer.

An acidity-triggered aggregation nanoplatform based on degradable mesoporous organosilica nanoparticles for precise drug delivery and phototherapy of focal bacterial infection

It is crucial to precisely strike the bacterially infected area and avoid damaging healthy tissue in bacterial infection treatment. Herein, we report an acidity-triggered aggregation antibacterial nanoplatform based on biodegradable mesoporous organic silica nanoparticles (MON NPs). The surface of MON NPs modified with polydopamine (PDA) encapsulated ciprofloxacin (CIP) and methylene blue (MB) and was then further grafted with glycol chitosan to obtain MB/CIP@MON-PDA-GCS NPs (MCMPG NPs). In the bacterial infection environment with acidic characteristics, glycol chitosan (GCS) becomes positively charged. Consequently, the positively charged acidity-triggered GCS enables MCMPG NPs to accumulate on the negatively charged bacterial surfaces in the infected area and not in healthy tissue. The targeted method allows for the precise release of CIP and MB, ensuring the spatial accuracy of photodynamic therapy (PDT) and photothermal therapy (PTT) for effective bacteria-specific treatment.

Integrin-Specific Stimuli-Responsive Nanomaterials for Cancer Theranostics

Background: Cancer is one of the leading causes of death worldwide. The tumor microenvironment makes the tumor difficult to treat, favoring drug resistance and the formation of metastases, resulting in death. Methods: Stimuli-responsive nanoparticles have shown great capacity to be used as a powerful strategy for cancer treatment, diagnostic, as well as theranostic. Nanocarriers are not only able to respond to internal stimuli such as oxidative stress, weakly acidic pH, high temperature, and the high expression of particular enzymes, but also to external stimuli such as light and paramagnetic characteristics to be exploited. Results: In this work, stimulus-responsive nanocarriers functionalized with arginine-glycine-aspartic acid (Arg-Gly-Asp) sequence as well as mimetic sequences with the capability to recognize integrin receptors are analyzed. Conclusions: This review highlights the progress that has been made in the development of new nanocarriers, capable of responding to endogenous and exogenous stimuli essential to combat cancer.

Zinc Influences the Efficacy of Betulinic Acid Treatment and Radiotherapy in Breast Cancer Cells

The trace element zinc influences a number of biological reactions, including cell growth, apoptosis, and DNA damage, which affect tumor therapy. The natural compound betulinic acid (BA) and its derivatives are known for their antiviral, antibacterial, and antitumor effects. Previous studies show that BA and 3-acetyl-28-sulfamoyloxybetulin (CAI3) have high cytotoxicity and induce radiosensitization in breast cancer cells. This study investigates the effects of zinc supplementation on treatment with BA or CAI3 and radiotherapy of breast cancer cell lines MDA-MB-231 and HS578T. Expression analysis shows that BA and CAI3 lead to altered expression of genes involved in zinc metabolism. Zinc supplementation affects cell survival and cell death alone and in combination with BA or CAI3 in both breast cancer cell lines. In MDA-MB-231 cells, zinc excess protects against ROS formation by BA or CAI3 and exhibits radioprotective effects compared to the single agent treatment. In contrast, in HS578T cells, zinc induces ROS formation but does not affect radiosensitivity. The variable effects of zinc on radiosensitivity highlight the importance of individualized treatment approaches. Although zinc has cytotoxic, pro-apoptotic, and anti-clonogenic effects, it seems worthwhile to consider its radioprotective properties when making treatment decisions in the case of adjuvant radiotherapy of breast cancer.

Nanoquercetin based nanoformulations for triple negative breast cancer therapy and its role in overcoming drug resistance

Triple Negative Breast Cancer (TNBC) is a highly aggressive and treatment-resistant subtype of breast cancer, lacking the expression of estrogen, progesterone, and HER2 receptors. Conventional chemotherapy remains the primary treatment option, but its efficacy is often compromised by the development of drug resistance. Nanoquercetin has garnered the attention of researchers due to its potential in combating cancer. This antioxidant exhibits significant efficacy against various types of cancer, including blood, breast, pancreatic, prostate, colon, and oral cancers. Functioning as a potential anti-cancer agent, nanoquercetin impedes the development and proliferation of cancer cells, induces apoptosis and autophagy, and prevents cancer cell invasion and metastasis. Numerous processes, such as the inhibition of pathways linked to angiogenesis, inflammation, and cell survival, are responsible for these anticancer actions. Moreover, it shields DNA from degradation caused by radiation and other carcinogens. The cost-effectiveness of current cancer treatments remains a significant challenge in healthcare, imposing a substantial economic burden on societies worldwide. Preclinical studies and early-phase clinical trials indicate that nanoquercetin-based therapies could offer a significant advancement in the management of TNBC, providing a foundation for future research and clinical application in overcoming drug resistance and improving patient outcomes. This article examines the latest data on nanoquercetin's potent anti-cancer properties and interprets the accumulated research findings within the framework of preventive, predictive, and personalized (3P) medicine.

Application of nanoparticles in breast cancer treatment: a systematic review

It is estimated that cancer is the second leading cause of death worldwide. The primary or secondary cause of cancer-related mortality for women is breast cancer. The main treatment method for different types of cancer is chemotherapy with drugs. Because of less water solubility of chemotherapy drugs or their inability to pass through membranes, their body absorbs them inadequately, which lowers the treatment's effectiveness. Drug specificity and pharmacokinetics can be changed by nanotechnology using nanoparticles. Instead, targeted drug delivery allows medications to be delivered to the targeted sites. In this review, we focused on nanoparticles as carriers in targeted drug delivery, their characteristics, structure, and the previous studies related to breast cancer. It was shown that nanoparticles could reduce the negative effects of chemotherapy drugs while increasing their effectiveness. Lipid-based nanocarriers demonstrated notable results in this instance, and some products that are undergoing various stages of clinical trials are among the examples. Nanoparticles based on metal or polymers demonstrated a comparable level of efficacy. With the number of cancer cases rising globally, many researchers are now looking into novel treatment approaches, particularly the use of nanotechnology and nanoparticles in the treatment of cancer. In order to help clinicians, this article aimed to gather more information about various areas of nanoparticle application in breast cancer therapy, such as modifying their synthesis and physicochemical characterization. It also sought to gain a deeper understanding of the mechanisms underlying the interactions between nanoparticles and biologically normal or infected tissues.

Protective effect of zinc oxide nanoparticles synthesized using Cassia alata for DSS-induced ulcerative colitis in mice model

The most prevalent form of inflammatory bowel disease (IBD), ulcerative colitis (UC), is characterized by persistent inflammation of the colorectal mucosa. It is asymptomatic, whereas Crohn's disease (CD) causes patchy lesions in the gastrointestinal tract. Men and women suffer equally from ulcerative colitis, which usually strikes in the second and third decades of life and becomes more common in senior citizens. In the present study, we produced zinc oxide nanoparticles using the natural herbal plant, Cassia alata. Zinc oxide nanoparticles have remarkable antimicrobial and antitumor benefits in the field of biomedical science. Furthermore, the synthesized zinc oxide nanoparticles (ZnO NPs) were characterized using UV, XRD, FTIR, and SEM analyses. The XRD analysis confirmed the crystallite nature and purity of the synthesized nanoparticles. Zinc oxide nanoparticles with a uniform size and partially agglomerated morphology were verified by SEM analysis. We investigated the protective effects of environmentally friendly zinc oxide nanoparticles in dextran sodium sulfate-induced ulcerative colitis mouse models. Green synthesized Cassia alata zinc oxide nanoparticles (CA ZnO NPs) reversed weight loss, disease activity index, colon shortening, and colon histological damage. Zinc oxide nanoparticles reduce hypersensitivity, oxidative stress, and inflammation, and protect the mucosal layer. Green synthesized CA ZnO NPs demonstrated protection against dextran sodium sulfate-induced ulcerative colitis via anti-inflammatory activity.

pH-Sensitive doxorubicin delivery using zinc oxide nanoparticles as a rectified theranostic platform: in vitro anti-proliferative, apoptotic, cell cycle arrest and in vivo radio-distribution studies

Despite enormous advancements in its management, cancer is the world's primary cause of mortality. Therefore, tremendous strides were made to produce intelligent theranostics with mitigated side effects and improved specificity and efficiency. Thus, we developed a pH-sensitive theranostic platform composed of dextran immobilized zinc oxide nanoparticles, loaded with doxorubicin and radiolabeled with the technetium-99m radionuclide (99mTc-labelled DOX-loaded ZnO@dextran). The platform measured 11.5 nm in diameter with -12 mV zeta potential, 88% DOX loading efficiency and 98.5% radiolabeling efficiency. It showed DOX release in a pH-responsive manner, releasing 93.1% cumulatively at pH 5 but just 7% at pH 7.4. It showed improved intracellular uptake, which resulted in a high growth suppressive effect against MCF-7 cancer cells as compared to the free DOX. It boasted a 4 times lower IC50 than DOX, indicating its significant anti-proliferative potential (0.14 and 0.55 μg ml-1, respectively). The in vitro biological evaluation revealed that its molecular mode of anti-proliferative action included downregulating Cdk-2, which provoked G1/S cell cycle arrest, and upregulating both the intracellular ROS level and caspase-3, which induced apoptosis and necrosis. The in vivo experiments in Ehrlich-ascites carcinoma bearing mice demonstrated that DOX-loaded ZnO@dextran showed a considerable 4-fold increase in anti-tumor efficacy compared to DOX. Moreover, by utilizing the diagnostic radionuclide (99mTc), the radiolabeled platform (99mTc-labelled DOX-loaded ZnO@dextran) was in vivo monitored in tumor-bearing mice, revealing high tumor accumulation (14% ID g-1 at 1 h p.i.) and reduced uptake in non-target organs with a 17.5 T/NT ratio at 1 h p.i. Hence, 99mTc-labelled DOX-loaded ZnO@dextran could be recommended as a rectified tumor-targeted theranostic platform.

Current development of theragnostic nanoparticles for women's cancer treatment

In the biomedical industry, nanoparticles (NPs-exclusively small particles with size ranging from 1-100 nanometres) are recently employed as powerful tools due to their huge potential in sophisticated and enhanced cancer theragnostic (i.e. therapeutics and diagnostics). Cancer is a life-threatening disease caused by carcinogenic agents and mutation in cells, leading to uncontrolled cell growth and harming the body's normal functioning while affecting several factors like low levels of reactive oxygen species, hyperactive antiapoptotic mRNA expression, reduced proapoptotic mRNA expression, damaged DNA repair, and so on. NPs are extensively used in early cancer diagnosis and are functionalized to target receptors overexpressing cancer cells for effective cancer treatment. This review focuses explicitly on how NPs alone and combined with imaging techniques and advanced treatment techniques have been researched against 'women's cancer' such as breast, ovarian, and cervical cancer which are substantially occurring in women. NPs, in combination with numerous imaging techniques (like PET, SPECT, MRI, etc) have been widely explored for cancer imaging and understanding tumor characteristics. Moreover, NPs in combination with various advanced cancer therapeutics (like magnetic hyperthermia, pH responsiveness, photothermal therapy, etc), have been stated to be more targeted and effective therapeutic strategies with negligible side effects. Furthermore, this review will further help to improve treatment outcomes and patient quality of life based on the theragnostic application-based studies of NPs in women's cancer treatment.

Zinc Oxide Nanoparticles and Cancer Chemotherapy: Helpful Tools for Enhancing Chemo-sensitivity and Reducing Side Effects?

Cancer chemotherapy is still a serious challenge. Chemo-resistance and destructive side effects of chemotherapy drugs are the most critical limitations of chemotherapy. Chemo-resistance is the leading cause of chemotherapy failure. Chemo-resistance, which refers to the resistance of cancer cells to the anticancer effects of chemotherapy drugs, is caused by various reasons. Among the most important of these reasons is the increase in the efflux of chemotherapy drugs due to the rise in the expression and activity of ABC transporters, the weakening of apoptosis, and the strengthening of stemness. In the last decade, a significant number of studies focused on the application of nanotechnology in cancer treatment. Considering the anti-cancer properties of zinc, zinc oxide nanoparticles have received much attention in recent years. Some studies have indicated that zinc oxide nanoparticles can target the critical mechanisms of cancer chemo-resistance and enhance the effectiveness of chemotherapy drugs. These studies have shown that zinc oxide nanoparticles can reduce the activity of ABC transporters, increase DNA damage and apoptosis, and attenuate stemness in cancer cells, leading to enhanced chemo-sensitivity. Some other studies have also shown that zinc oxide nanoparticles in low doses can be helpful in minimizing the harmful side effects of chemotherapy drugs. In this article, after a brief overview of the mechanisms of chemo-resistance and anticancer effects of zinc, we will review all these studies in detail.

Apoptosis Induction by ZnFe2O4-Ag Biosynthesized by Chlorella vulgaris in MCF-7 Breast Cancer Cell Line

The incidence and mortality of breast cancer are growing which indicates the inefficiency of the current chemotherapy drugs. Due to the anticancer potential of Zn and Ag and the magnetic feature of iron oxide, in this work, we synthesized ZnFe2O4-Ag nanocomposite using Chlorella vulgaris and investigated its anticancer effect on breast cancer cell line. Physicochemical characterization was performed by FT-IR, XRD, SEM, TEM, VSM, EDS mapping, UV, and zeta potential assays. Cell cytotoxicity and apoptosis frequency were studied by the MTT and flow cytometry assays. Also, cell cycle analysis, Hoechst staining, and measuring ROS (reactive oxygen species) level were performed. The synthesized particles were almost spherical with a size range of 14-52 nm. The FT-IR and XRD assays confirmed the proper synthesis of the particles and VSM analysis showed that particles had magnetic property and the maximum saturation magnetization was 0.8 Emu/g. Also, the EDS mapping of the nanocomposite showed the Zn, Fe, O, and Ag elements. The MTT assay showed that the 50% inhibitory concentration (IC50) of ZnFe2O4-Ag for breast cancer and normal cells were 28 and 154 µg/mL, respectively, and the nanocomposite had stronger anticancer activity than cisplatin (IC50 = 84 µg/mL). Flow cytometry analysis showed that the exposure to the nanocomposite induced cell apoptosis by 77.5% and significantly induced ROS generation. Also, treating breast cancer cells with the nanocomposite induced cell cycle arrest and apoptotic features, including chromatin condensation and fragmentation. In conclusion, ZnFe2O4-Ag nanocomposite synthesized by C. vulgaris could suppress the proliferation of breast cancer cells by the generation of oxidative stress, apoptosis induction, and cell cycle arrest.

ZnO based 0-3D diverse nano-architectures, films and coatings for biomedical applications

Thin-film nano-architecting is a promising approach that controls the properties of nanoscale surfaces to increase their interdisciplinary applications in a variety of fields. In this context, zinc oxide (ZnO)-based various nano-architectures (0-3D) such as quantum dots, nanorods/nanotubes, nanothin films, tetrapods, nanoflowers, hollow structures, etc. have been extensively researched by the scientific community in the past decade. Owing to its unique surface charge transport properties, optoelectronic properties and reported biomedical applications, ZnO has been considered as one of the most important futuristic bio-nanomaterials. This review is focused on the design/synthesis and engineering of 0-3D nano-architecture ZnO-based thin films and coatings with tunable characteristics for multifunctional biomedical applications. Although ZnO has been extensively researched, ZnO thin films composed of 0-3D nanoarchitectures with promising thin film device bio-nanotechnology applications have rarely been reviewed. The current review focuses on important details about the technologies used to make ZnO-based thin films, as well as the customization of properties related to bioactivities, characterization, and device fabrication for modern biomedical uses that are relevant. It features biosensing, tissue engineering/wound healing, antibacterial, antiviral, and anticancer activity, as well as biomedical diagnosis and therapy with an emphasis on a better understanding of the mechanisms of action. Eventually, key issues, experimental parameters and factors, open challenges, etc. in thin film device fabrications and applications, and future prospects will be discussed, followed by a summary and conclusion.

Anticandidal effectiveness of greenly synthesized zinc oxide nanoparticles against candidal pathogens

Drug resistance of pathogenic candidal strains to conventional antifungal agents represents a significant health issue contributing to high morbidity worldwide. Hence, the aim of the current study focused on evaluating the antifungal and synergistic activities of the green synthesized zinc oxide nanoparticles formulated using Laurus nobilis leaf extract. The biogenic ZnONPs were hexagonal in shape with average particle size diameter of 37.98 nm and pure crystalline structure as detected by XRD data. The highest antifungal activity of biogenic ZnONPs was detected against Candida parapsilosis strain demonstrating relative inhibitory zone diameters of 17.13 ± 0.74 and 25.78 ± 0.47 mm, at the concentrations of 100 and 200 µg/disk, respectively. Moreover, the biogenic ZnONPs demonstrated the highest synergistic activity with clotrimazole antifungal agent against Candida glabrata followed by Candida auris strains. MTT assay revealed that the biogenic ZnONPs showed low toxicity demonstrating relative IC50 value of 774.45 µg/mL against normal lung fibroblast cells which further affirmed their biosafety for application. In conclusion, the bioinspired ZnONPs could be utilized for the formulation of effective antifungal agents against drug resistant candidal strains and also could be combined with antifungal agents to boost their antifungal efficiency.

Receptor-Targeted Dual pH-Triggered Intracellular Protein Transfer

Protein therapeutics are of widespread interest due to their successful performance in the current pharmaceutical and medical fields, even though their broad applications have been hindered by the lack of an efficient intracellular delivery approach. Herein, we fabricated an active-targeted dual pH-responsive delivery system with favorable tumor cell entry augmented by extracellular pH-triggered charge reversal and tumor receptor targeting and pH-controlled endosomal release in a traceless fashion. As a traceable model protein, the enhanced green fluorescent protein (eGFP) bearing a nuclear localization signal was covalently coupled with a pH-labile traceless azidomethyl-methylmaleic anhydride (AzMMMan) linker followed by functionalization with different molar equivalents of two dibenzocyclooctyne-octa-arginine-cysteine (DBCO-R8C)-modified moieties: polyethylene glycol (PEG)-GE11 peptide for epidermal growth factor receptor-mediated targeting and melittin for endosomal escape. The cationic melittin domain was masked with tetrahydrophthalic anhydride revertible at mild acidic pH 6.5. At the optimally balanced ratio of functional units, the on-demand charge conversion at tumoral extracellular pH 6.5 in combination with GE11-mediated targeting triggered enhanced electrostatic cellular attraction by the R8C cell-penetrating peptides and melittin, as demonstrated by strongly enhanced cellular uptake. Successful endosomal release followed by nuclear localization of the eGFP cargo was obtained by taking advantage of melittin-mediated endosomal escape and rapid traceless release from the AzMMMan linker. The effectiveness of this multifunctional bioresponsive system suggests a promising strategy for delivery of protein drugs toward intracellular targets. A possible therapeutic relevance was indicated by an example of cytosolic delivery of cytochrome c initiating the apoptosis pathway to kill cancer cells.

Application of Nanoparticles for Efficient Delivery of Quercetin in Cancer Cells

Quercetin (Qu, 3,5,7,3', 4'-pentahydroxyflavanone) is a natural polyphenol compound abundantly found in health food or plant-based products. In recent decades, Qu has gained significant attention in the food, cosmetic, and pharmaceutic industries owning to its wide beneficial therapeutic properties such as antioxidant, anti-inflammatory and anticancer activities. Despite the favorable roles of Qu in cancer therapy due to its numerous impacts on the cell signaling axis, its poor chemical stability and bioavailability, low aqueous solubility as well as short biological half-life have limited its clinical application. Recently, drug delivery systems based on nanotechnology have been developed to overcome such limitations and enhance the Qu biodistribution following administration. Several investigations have indicated that the nano-formulation of Qu enjoys more remarkable anticancer effects than its free form. Furthermore, incorporating Qu in various nano-delivery systems improved its sustained release and stability, extended its circulation time, enhanced its accumulation at target sites, and increased its therapeutic efficiency. The purpose of this study was to provide a comprehensive review of the anticancer properties of various Qu nano-formulation to augment their effects on different malignancies. Various targeting strategies for improving Qu delivery, including nanoliposomes, lipids, polymeric, micelle, and inorganic nanoparticle NPs, have been discussed in this review. The results of the current study illustrated that a combination of appropriate nano encapsulation approaches with tumor-oriented targeting delivery might lead to establishing QU nanoparticles that can be a promising technique for cancer treatment.

An Updated Insight into Phytomolecules and Novel Approaches used in the Management of Breast Cancer

Breast cancer is a widespread condition that kills more women from cancer-related causes than any other type of cancer globally. Women who have estrogen-dependent, initial metastatic breast cancer frequently receive treatment with surgery, radiation therapy, and chemotherapy. They may also get more specialized treatments like tamoxifen or aromatase inhibitors (anastrozole or letrozole). The World Health Organisation reported in 2012 that by 2030, breast cancer will be more common worldwide. There are several phytochemicals, such as isoflavones, coumestans, lignans, and prenylflavonoides. Isoflavones have been shown in studies to prevent the spread of breast cancer and to trigger apoptosis. Targeting BCs in metastatic breast cancer may be made possible by combining well-formulated phytochemicals in nanoparticles or other novel drug delivery agents with currently accepted endocrine and/or conventional chemotherapies. Cell signaling, regulation of cell cycles, oxidative stress action, and inflammation could be positively impacted by phytoconstituents. They have the ability to alter non-coding RNAs, to prevent the proliferation and regeneration of cancer cells. The availability of novel approaches helps in disease targeting, safety, effectiveness and efficacy. The current literature helps to know the available drugs i.e. phytoconstituents or novel drug delivery like nanoparticle, microsphere, micelles, liposomes and neosomes. The literature has been taken from PubMed, Google Scholar, SciFinder, or other internet sites.

Apoptosis Induction in HepG2 and HCT116 Cells by a Novel Quercetin-Zinc (II) Complex: Enhanced Absorption of Quercetin and Zinc (II)

Quercetin forms complexes with various metals due to its structural attributes. It predominantly exhibits chelating activity at the 3-hydroxy/4-carbonyl group. Previously, coordination in synthetically obtained quercetin-zinc (II) complexes has been limited to this group. However, the expanded coordination observed in quercetin-iron complexes has opened avenues for diverse applications. Thus, synthesizing novel quercetin-zinc complexes with different coordination positions is a significant advance. In our study, we not only synthesized and comprehensively characterized a new quercetin-zinc (II) complex, Zn-Q, but also evaluated the structure and bioactivity of chelate complexes (Q+Zn) derived from co-treatment in cell culture mediums. The structure of the new compound Zn-Q was comprehensively characterized using 1D 1H and 2D correlation spectroscopy (COSY), nuclear magnetic resonance (NMR), Fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-Vis), electrospray ionization mass spectrometer (ESI-MS), and X-ray diffraction analysis (XRD) analysis. Subcellular localization and absorption of these zinc (II) complexes were determined using the ZnAF-2 DA zinc ion fluorescence probe. Throughout the experiments, both Zn-Q and Q+Zn exhibited significant antioxidant, cell growth inhibitory, and anticancer effects in HepG2 and HCT116 cells, with Zn-Q showing the highest potential for inducing apoptosis via the caspase pathway. Tracking intracellular zinc complex absorption using zinc fluorescent probes revealed zinc (II) localization around the cell nucleus. Interestingly, there was a proportional increase in intracellular quercetin absorption in conjunction with zinc (II) uptake. Our research highlights the advantages of quercetin complexation with zinc (II): enhanced anticancer efficacy compared to the parent compound and improved bioavailability of both quercetin and zinc (II). Notably, our findings, which include enhanced intracellular uptake of both quercetin and zinc (II) upon complex formation and its implications in apoptosis, contribute significantly to the understanding of metal-polyphenol complexes. Moving forward, comprehensive functional assessments and insights into its mechanism of action, supported by animal studies, are anticipated.

Nanoformulations of quercetin for controlled delivery: a review of preclinical anticancer studies

One of the well-studied older molecules, quercetin, is found in large quantities in many fruits and vegetables. Natural anti-oxidant quercetin has demonstrated numerous pharmacological properties in preclinical and clinical research, including anti-inflammatory and anti-cancer effects. Due to its ability to control cell signaling pathways, including NF-κB, p53, activated protein-1 (AP-1), STAT3, and epidermal growth response-1 (Egr-1), which is essential in the initiation and proliferation of cancer, it has gained a lot of fame as an anticancer molecule. Recent research suggests that using nanoformulations can help quercetin to overcome its hydrophobicity while also enhancing its stability and cellular bioavailability both in vitro and in vivo. The main aim of this review is to focus on the comprehensive insights of several nanoformulations, including liposomes, nano gels, micelles, solid lipid nanoparticles (SLN), polymer nanoparticles, gold nanoparticles, and cyclodextrin complexes, to transport quercetin for application in cancer.

Synthesis of Quercetin-Loaded Silver Nanoparticles and Assessing Their Anti-Bacterial Potential

The study delves into the multifaceted potential of quercetin (Qu), a phytoconstituent found in various fruits, vegetables, and medicinal plants, in combination with silver nanoparticles (AgNPs). The research explores the synthesis and characterization of AgNPs loaded with Qu and investigates their pharmaceutical applications, particularly focusing on antibacterial properties. The study meticulously evaluates Qu's identity, and physicochemical properties, reaffirming its suitability for pharmaceutical use. The development of Qu-loaded AgNPs demonstrates their high drug entrapment efficiency, ideal particle characteristics, and controlled drug release kinetics, suggesting enhanced therapeutic efficacy and reduced side effects. Furthermore, the research examines the antibacterial activity of Qu in different solvents, revealing distinct outcomes. Qu, both in methanol and water formulations, exhibits antibacterial activity against Escherichia coli, with the methanol formulation displaying a slightly stronger efficacy. In conclusion, this study successfully synthesizes AgNPs loaded with Qu and highlights their potential as a potent antibacterial formulation. The findings underscore the influence of solvent choice on Qu's antibacterial properties and pave the way for further research and development in drug delivery systems and antimicrobial agents. This innovative approach holds promise for addressing microbial resistance and advancing pharmaceutical formulations for improved therapeutic outcomes.

Lipid-based nanoparticle-mediated combination therapy for breast cancer management: a comprehensive review

Breast cancer due to the unpredictable and complex etiopathology combined with the non-availability of any effective drug treatment has become the major root of concern for oncologists globally. The number of women affected by the said disease state is increasing at an alarming rate attributed to environmental and lifestyle changes indicating at the exploration of a novel treatment strategy that can eradicate this aggressive disease. So far, it is treated by promising nanomedicine monotherapy; however, according to the numerous studies conducted, the inadequacy of these nano monotherapies in terms of elevated toxicity and resistance has been reported. This review, therefore, puts forth a new multimodal strategic approach to lipid-based nanoparticle-mediated combination drug delivery in breast cancer, emphasizing the recent advancements. A basic overview about the combination therapy and its index is firstly given. Then, the various nano-based combinations of chemotherapeutics involving the combination delivery of synthetic and herbal agents are discussed along with their examples. Further, the recent exploration of chemotherapeutics co-delivery with small interfering RNA (siRNA) agents has also been explained herein. Finally, a section providing a brief description of the delivery of chemotherapeutic agents with monoclonal antibodies (mAbs) has been presented. From this review, we aim to provide the researchers with deep insight into the novel and much more effective combinational lipid-based nanoparticle-mediated nanomedicines tailored specifically for breast cancer treatment resulting in synergism, enhanced antitumor efficacy, and low toxic effects, subsequently overcoming the hurdles associated with conventional chemotherapy.

(Nano)platforms in breast cancer therapy: Drug/gene delivery, advanced nanocarriers and immunotherapy

Breast cancer is the most malignant tumor in women, and there is no absolute cure for it. Although treatment modalities including surgery, chemotherapy, and radiotherapy are utilized for breast cancer, it is still a life-threatening disease for humans. Nanomedicine has provided a new opportunity in breast cancer treatment, which is the focus of the current study. The nanocarriers deliver chemotherapeutic agents and natural products, both of which increase cytotoxicity against breast tumor cells and prevent the development of drug resistance. The efficacy of gene therapy is boosted by nanoparticles and the delivery of CRISPR/Cas9, Noncoding RNAs, and RNAi, promoting their potential for gene expression regulation. The drug and gene codelivery by nanoparticles can exert a synergistic impact on breast tumors and enhance cellular uptake via endocytosis. Nanostructures are able to induce photothermal and photodynamic therapy for breast tumor ablation via cell death induction. The nanoparticles can provide tumor microenvironment remodeling and repolarization of macrophages for antitumor immunity. The stimuli-responsive nanocarriers, including pH-, redox-, and light-sensitive, can mediate targeted suppression of breast tumors. Besides, nanoparticles can provide a diagnosis of breast cancer and detect biomarkers. Various kinds of nanoparticles have been employed for breast cancer therapy, including carbon-, lipid-, polymeric- and metal-based nanostructures, which are different in terms of biocompatibility and delivery efficiency.

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.

Augmentation of anti-proliferative efficacy of quercetin encapsulated chitosan nanoparticles by induction of cell death via mitochondrial membrane permeabilization in oral cancer

Quercetin (QCT), an antioxidant plant flavonoid, is known to impart prominent anti-cancer properties. However, its clinical application as a potential drug is hindered owing to its hydrophobicity, extensive metabolism, low absorption, and rapid elimination. The drawbacks of these phytochemical-based therapies can be addressed using nanotechnology-based drug delivery systems. In this study, we sought to develop chitosan nanoparticles (CSNPs) as the drug vehicle for encasing quercetin (QCT-CSNPs) and further investigate its anti-tumor potential against human oral cancer cell line Cal33. Our findings indicate that the average particle diameter of the formulated chitosan nanoparticles was around 100 nm, and they had a spherical structure, as per the TEM and FESEM images. The efficient entrapment of quercetin inside the CSNPs matrix is confirmed by XRD, UV-Vis spectrophotometry, FTIR, and DSC analysis. The in vitro cell cytotoxicity study against Cal33 oral cancer cells revealed that QCT-CSNPs exhibited superior toxicity compared to free QCT post-24-hour treatment. The improved anti-cancer efficacy of QCT-CSNPs was further confirmed by enhanced cellular apoptosis, colony formation inhibition, migration inhibition, and chromatin condensation. Moreover, the mitochondrial dysfunction and enhanced ROS (Reactive oxygen species) production indicated mitochondrial-mediated cell death in QCT-CSNPs treated Cal33 cells. In conclusion, our data suggest that quercetin-encapsulated chitosan nanoparticles may serve as a potential drug candidate against oral cancer.

Layered Clay Minerals in Cancer Therapy: Recent Progress and Prospects

Cancer is one of the deadliest diseases, and current treatment regimens suffer from limited efficacy, nonspecific toxicity, and chemoresistance. With the advantages of good biocompatibility, large specific surface area, excellent cation exchange capacity, and easy availability, clay minerals have been receiving ever-increasing interests in cancer treatment. They can act as carriers to reduce the toxic side effects of chemotherapeutic drugs, and some of their own properties can kill cancer cells, etc. Compared with other morphologies clays, layered clay minerals (LCM) have attracted more and more attention due to adjustable interlayer spacing, easier ion exchange, and stronger adsorption capacity. In this review, the structure, classification, physicochemical properties, and functionalization methods of LCM are summarized. The state-of-the-art progress of LCM in antitumor therapy is systematically described, with emphasis on the application of montmorillonite, kaolinite, and vermiculite. Furthermore, the property-function relationships of LCM are comprehensively illustrated to reveal the design principles of clay-based antitumor systems. Finally, foreseeable challenges and outlook in this field are discussed.

Functionalized and Nonfunctionalized Nanosystems for Mitochondrial Drug Delivery with Metallic Nanoparticles

Background: The application of metallic nanoparticles as a novel therapeutic tool has significant potential to facilitate the treatment and diagnosis of mitochondria-based disorders. Recently, subcellular mitochondria have been trialed to cure pathologies that depend on their dysfunction. Nanoparticles made from metals and their oxides (including gold, iron, silver, platinum, zinc oxide, and titanium dioxide) have unique modi operandi that can competently rectify mitochondrial disorders. Materials: This review presents insight into the recent research reports on exposure to a myriad of metallic nanoparticles that can alter the dynamic ultrastructure of mitochondria (via altering metabolic homeostasis), as well as pause ATP production, and trigger oxidative stress. The facts and figures have been compiled from more than a hundred PubMed, Web of Science, and Scopus indexed articles that describe the essential functions of mitochondria for the management of human diseases. Result: Nanoengineered metals and their oxide nanoparticles are targeted at the mitochondrial architecture that partakes in the management of a myriad of health issues, including different cancers. These nanosystems not only act as antioxidants but are also fabricated for the delivery of chemotherapeutic agents. However, the biocompatibility, safety, and efficacy of using metal nanoparticles is contested among researchers, which will be discussed further in this review.

Recent Advances in Nanoformulations for Quercetin Delivery

Quercetin (QUE) is a flavonol that has recently received great attention from the research community due to its important pharmacological properties. However, QUE's low solubility and extended first-pass metabolism limit its oral administration. This review aims to present the potential of various nanoformulations in the development of QUE dosage forms for bioavailability enhancement. Advanced drug delivery nanosystems can be used for more efficient encapsulation, targeting, and controlled release of QUE. An overview of the primary nanosystem categories, formulation processes, and characterization techniques are described. In particular, lipid-based nanocarriers, such as liposomes, nanostructured-lipid carries, and solid-lipid nanoparticles, are widely used to improve QUE's oral absorption and targeting, increase its antioxidant activity, and ensure sustained release. Moreover, polymer-based nanocarriers exhibit unique properties for the improvement of the Absorption, Distribution, Metabolism, Excretion, and Toxicology (ADME(T)) profile. Namely, micelles and hydrogels composed of natural or synthetic polymers have been applied in QUE formulations. Furthermore, cyclodextrin, niosomes, and nanoemulsions are proposed as formulation alternatives for administration via different routes. This comprehensive review provides insight into the role of advanced drug delivery nanosystems for the formulation and delivery of QUE.

Nanomedicine in therapeutic warfront against estrogen receptor-positive breast cancer

Breast cancer (BC) is the most frequently diagnosed malignancy in women worldwide. Almost 70-80% of cases of BC are curable at the early non-metastatic stage. BC is a heterogeneous disease with different molecular subtypes. Around 70% of breast tumors exhibit estrogen-receptor (ER) expression and endocrine therapy is used for the treatment of these patients. However, there are high chances of recurrence in the endocrine therapy regimen. Though chemotherapy and radiation therapy have substantially improved survival rates and treatment outcomes in BC patients, there is an increased possibility of the development of resistance and dose-limiting toxicities. Conventional treatment approaches often suffer from low bioavailability, adverse effects due to the non-specific action of chemotherapeutics, and low antitumor efficacy. Nanomedicine has emerged as a conspicuous strategy for delivering anticancer therapeutics in BC management. It has revolutionized the area of cancer therapy by increasing the bioavailability of the therapeutics and improving their anticancer efficacy with reduced toxicities on healthy tissues. In this article, we have highlighted various mechanisms and pathways involved in the progression of ER-positive BC. Further, different nanocarriers delivering drugs, genes, and natural therapeutic agents for surmounting BC are the spotlights of this article.

Current Principles, Challenges, and New Metrics in pH-Responsive Drug Delivery Systems for Systemic Cancer Therapy

The paradigm of drug delivery via particulate formulations is one of the leading ideas that enable overcoming limitations of traditional chemotherapeutic agents. The trend toward more complex multifunctional drug carriers is well-traced in the literature. Nowadays, the prospectiveness of stimuli-responsive systems capable of controlled cargo release in the lesion nidus is widely accepted. Both endogenous and exogenous stimuli are employed for this purpose; however, endogenous pH is the most common trigger. Unfortunately, scientists encounter multiple challenges on the way to the implementation of this idea related to the vehicles' accumulation in off-target tissues, their immunogenicity, the complexity of drug delivery to intracellular targets, and finally, the difficulties in the fabrication of carriers matching all imposed requirements. Here, we discuss fundamental strategies for pH-responsive drug delivery, as well as limitations related to such carriers' application, and reveal the main problems, weaknesses, and reasons for poor clinical results. Moreover, we attempted to formulate the profiles of an "ideal" drug carrier in the frame of different strategies drawing on the example of metal-comprising materials and considered recently published studies through the lens of these profiles. We believe that this approach will facilitate the formulation of the main challenges facing researchers and the identification of the most promising trends in technology development.

Natural Compounds, Optimal Combination of Brusatol and Polydatin Promote Anti-Tumor Effect in Breast Cancer by Targeting Nrf2 Signaling Pathway

Triple-negative breast cancer (TNBC) has been clearly recognized as a heterogeneous tumor with the worst prognosis among the subtypes of breast cancer (BC). The advent and application of current small-molecule drugs for treating TNBC, as well as other novel inhibitors, among others, have made treatment options for TNBC more selective. However, there are still problems, such as poor patient tolerance, large administration doses, high dosing frequency, and toxic side effects, necessitating the development of more efficient and less toxic treatment strategies. High expression of Nrf2, a vital antioxidant transcription factor, often promotes tumor progression, and it is also one of the most effective targets in BC therapy. We found that in MDA-MB-231 cells and SUM159 cells, brusatol (BRU) combined with polydatin (PD) could significantly inhibit cell proliferation in vitro, significantly downregulate the expression of Nrf2 protein as well as the expression of downstream related target genes Heme Oxygenase-1 (HO-1) and NAD(P)H dehydrogenase, quinone 1 (NQO1), and promote reactive oxygen species (ROS) levels to further strengthen the anti-tumor effect. Furthermore, we discovered in our in vivo experiments that by reducing the drug dosage three times, we could significantly reduce tumor cell growth while avoiding toxic side effects, providing a treatment method with greater clinical application value for TNBC treatment.

Current Understanding of Flavonoids in Cancer Therapy and Prevention

Cancer is a major cause of death worldwide, with multiple pathophysiological manifestations. In particular, genetic abnormalities, inflammation, bad eating habits, radiation exposure, work stress, and toxin consumption have been linked to cancer disease development and progression. Recently, natural bioactive chemicals known as polyphenols found in plants were shown to have anticancer capabilities, destroying altered or malignant cells without harming normal cells. Flavonoids have demonstrated antioxidant, antiviral, anticancer, and anti-inflammatory effects. Flavonoid type, bioavailability, and possible method of action determine these biological actions. These low-cost pharmaceutical components have significant biological activities and are beneficial for several chronic disorders, including cancer. Recent research has focused primarily on isolating, synthesizing, and studying the effects of flavonoids on human health. Here we have attempted to summarize our current knowledge of flavonoids, focusing on their mode of action to better understand their effects on cancer.

Antimicrobial Nano-Zinc Oxide Biocomposites for Wound Healing Applications: A Review

Chronic wounds are a major concern for global health, affecting millions of individuals worldwide. As their occurrence is correlated with age and age-related comorbidities, their incidence in the population is set to increase in the forthcoming years. This burden is further worsened by the rise of antimicrobial resistance (AMR), which causes wound infections that are increasingly hard to treat with current antibiotics. Antimicrobial bionanocomposites are an emerging class of materials that combine the biocompatibility and tissue-mimicking properties of biomacromolecules with the antimicrobial activity of metal or metal oxide nanoparticles. Among these nanostructured agents, zinc oxide (ZnO) is one of the most promising for its microbicidal effects and its anti-inflammatory properties, and as a source of essential zinc ions. This review analyses the most recent developments in the field of nano-ZnO–bionanocomposite (nZnO-BNC) materials—mainly in the form of films, but also hydrogel or electrospun bandages—from the different preparation techniques to their properties and antibacterial and wound-healing performances. The effect of nanostructured ZnO on the mechanical, water and gas barrier, swelling, optical, thermal, water affinity, and drug-release properties are examined and linked to the preparation methods. Antimicrobial assays over a wide range of bacterial strains are extensively surveyed, and wound-healing studies are finally considered to provide a comprehensive assessment framework. While early results are promising, a systematic and standardised testing procedure for the comparison of antibacterial properties is still lacking, partly because of a not-yet fully understood antimicrobial mechanism. This work, therefore, allowed, on one hand, the determination of the best strategies for the design, engineering, and application of n-ZnO-BNC, and, on the other hand, the identification of the current challenges and opportunities for future research.

Apoptotic Mechanisms of Quercetin in Liver Cancer: Recent Trends and Advancements

Due to rising incidence rates of liver cancer and worries about the toxicity of current chemotherapeutic medicines, the hunt for further alternative methods to treat this malignancy has escalated. Compared to chemotherapy, quercetin, a flavonoid, is relatively less harmful to normal cells and is regarded as an excellent free-radical scavenger. Apoptotic cell death of cancer cells caused by quercetin has been demonstrated by many prior studies. It is present in many fruits, vegetables, and herbs. Quercetin targets apoptosis, by upregulating Bax, caspase-3, and p21 while downregulating Akt, PLK-1, cyclin-B1, cyclin-A, CDC-2, CDK-2, and Bcl-2. Additionally, it has been reported to increase STAT3 protein degradation in liver cancer cells while decreasing STAT3 activation. Quercetin has a potential future in chemoprevention, based on substantial research on its anticancer effects. The current review discusses quercetin's mechanisms of action, nanodelivery strategies, and other potential cellular effects in liver cancer.

Drug Delivery Systems in Regenerative Medicine: An Updated Review

Modern drug discovery methods led to evolving new agents with significant therapeutic potential. However, their properties, such as solubility and administration-related challenges, may hinder their benefits. Moreover, advances in biotechnology resulted in the development of a new generation of molecules with a short half-life that necessitates frequent administration. In this context, controlled release systems are required to enhance treatment efficacy and improve patient compliance. Innovative drug delivery systems are promising tools that protect therapeutic proteins and peptides against proteolytic degradation where controlled delivery is achievable. The present review provides an overview of different approaches used for drug delivery.

Quercetin Induces Apoptosis in HepG2 Cells via Directly Interacting with YY1 to Disrupt YY1-p53 Interaction

Quercetin is a flavonol found in edible plants and possesses a significant anticancer activity. This study explored the mechanism by which quercetin prevented liver cancer via inducing apoptosis in HepG2 cells. Quercetin induced cell proliferation and apoptosis through inhibiting YY1 and facilitating p53 expression and subsequently increasing the Bax/Bcl-2 ratio. The results revealed that YY1 knockdown promoted apoptosis, whilst YY1 overexpression suppressed apoptosis via direct physical interaction between YY1 and p53 to regulate the p53 signaling pathway. Molecular docking using native and mutant YY1 proteins showed that quercetin could interact directly with YY1, and the binding of quercetin to YY1 significantly decreased the docking energy of YY1 with p53 protein. The interactions between quercetin and YY1 protein included direct binding and non-bonded indirect interactions, as confirmed by cellular thermal shift assay, UV-Vis absorption spectroscopy, fluorescence spectroscopy and circular dichroism spectroscopy. It was likely that quercetin directly bound to YY1 protein to compete with p53 for the binding sites of YY1 to disrupt the YY1-p53 interaction, thereby promoting p53 activation. This study provides insights into the mechanism underlying quercetin's anticancer action and supports the development of quercetin as an anticancer therapeutic agent.

pH-responsive and targeted delivery of chrysin via folic acid-functionalized mesoporous silica nanocarrier for breast cancer therapy

Cancer is a disease of global importance. In order to mitigate conventional chemotherapy-related side effects, phytochemicals with inherent anticancer efficacy have been opted. However, the use of nanotechnology is essential to enhance the bioavailability and therapeutic efficacy of these phytochemicals. Herein, we have formulated folic acid conjugated polyacrylic acid capped mesoporous silica nanoparticles (∼47.6 nm in diameter) for pH-dependent targeted delivery of chrysin to breast cancer (MCF-7) cells. Chrysin loaded mesoporous silica nanoparticles (Chr- mSiO2@PAA/FA) have been noted to induce apoptosis in MCF-7 cells through oxidative insult and mitochondrial dysfunction with subsequent G1 arrest. Further, in tumor bearing mice, intravenous incorporation of Chr-mSiO2@PAA/FA has been noticed to enhance the anti-neoplastic effects of chrysin via tumor site-specific accumulation. Enhanced cytotoxicity of chrysin contributed towards in vivo tumor regression, restoration of normalized tissue architecture and maintenance of healthy body weight. Besides, no serious systemic toxicity was manifested in response to Chr-mSiO2@PAA/FA administration in vivo. Thus, the study evokes about the anticancer potentiality of chrysin and its increased therapeutic activity via incorporation into folic acid conjugated mesoporous silica nanoparticles, which may hold greater impact in field of future biomedical research.

Recent advances in flavonoid-based nanocarriers as an emerging drug delivery approach for cancer chemotherapy

Flavonoids are an interesting class of biomolecules, which exhibit cancer-inhibitory effects through both chemopreventive and chemotherapeutic activities. However, their therapeutic efficacy is affected by poor pharmacokinetics (PK) and biopharmaceutical attributes. One of the most promising approaches to resolve these issues is to formulate flavonoids in nanosystems. Different flavonoid nanoformulations have shown therapeutic superiority over free flavonoids. Functionalization of nanoparticles (NPs) further improves their therapeutic efficacy by facilitating site-specific delivery and reducing nonspecific toxicities. In this review, we highlight recent developments in the field of flavonoid-based NPs to gain translational insights into the potential applications of flavonoid-based nanocarriers in cancer management.

Microwave-Induced CuO Nanorods: A Comparative Approach between Curcumin, Quercetin, and Rutin to Study Their Antioxidant, Antimicrobial, and Anticancer Effects against Normal Skin Cells and Human Breast Cancer Cell Lines MCF-7 and T-47D

Herein, we explore the biological properties of curcumin, quercetin, and rutin by loading them onto porous CuO nanorods (NRs). The CuO NRs were synthesized using the microwave irradiation method through a chemical reaction between CuSO₄·5H₂O and NaOH in the presence of the anionic stabilizer sodium dodecyl sulfate. The shape and surface morphology of CuO NRs were examined with two microscopic techniques: high-resolution transmission electron microscopy (HR-TEM) and field emission scanning electron microscopy (FESEM). Their average diameter was measured by TEM to be 15 ± 2 nm. The porosity and interfacial area of the fabricated material were determined by Brunauer-Emmett-Teller analysis. After successful synthesis, CuO NRs were loaded with polyphenolic curcumin, quercetin, and rutin, with the loading efficiency of 57.8, 62.2, and 81.2%, respectively, which was confirmed by UV-visible and infra-red spectroscopy and finally with a thermal gravimetric technique. Their radical scavenging activity was measured with the 2,2-diphenyl-1-picrylhydrazyl radical and compared with the control (ascorbic acid). Further, good bactericidal effects were observed against both Gram-positive bacterial strains, including Staphylococcus aureus and Bacillus subtilis, and Gram-negative bacterial strains, including Salmonella typhi, Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae. Excellent anticancer activity was observed against normal skin cells and breast cancer cells T-47D and MCF-7.