The Role of Functionalization and Size of Gold Nanoparticles in the Response of MCF-7 Breast Cancer Cells to Ionizing Radiation Comparing 2D and 3D In Vitro Models

Tumour cell-induced platelet aggregation in breast cancer: Scope of metal nanoparticles

Breast cancer is a major cause of cancer-related mortality among the female population worldwide. Among the various factors promoting breast cancer metastasis, the role of cancer-cell platelet interactions leading to tumour cell-induced platelet aggregation (TCIPA) has garnered significant attention recently. Our state-of-the-art literature review verifies the implications of metal nanoparticles in breast cancer research and TCIPA-specific breast cancer metastasis. We have evaluated in vitro and in vivo research data as well as clinical investigations within the scope of this topic presented in the last ten years. Nanoparticle-based drug delivery platforms in cancer therapy can combat the growing concerns of multi-drug resistance, the alarming rates of chemotherapy-induced toxicities and cancer progression. Metal nanoparticles conjugated with chemotherapeutics can outperform their free drug counterparts in achieving targeted drug delivery and desired drug concentration inside the tumour tissue with minimal toxic effects. Existing data highlights the potential of metal nanoparticles as a promising tool for targeting the platelet-specific interactions associated with breast cancer metastasis including TCIPA.

An Evaluation of the Potential Radiosensitization Effect of Spherical Gold Nanoparticles to Induce Cellular Damage Using Different Radiation Qualities

Global disparities in cancer prevention, detection, and treatment demand a unified international effort to reduce the disease's burden and improve outcomes. Despite advances in chemotherapy and radiotherapy, many tumors remain resistant to these treatments. Gold nanoparticles (AuNPs) have shown promise as radiosensitizers, enhancing the effectiveness of low-energy X-rays by emitting Auger electrons that cause localized cellular damage. In this study, spherical AuNPs of 5 nm and 10 nm were characterized and tested on various cell lines, including malignant breast cells (MCF-7), non-malignant cells (CHO-K1 and MCF-10A), and human lymphocytes. Cells were treated with AuNPs and irradiated with attenuated 6 megavoltage (MV) X-rays or p(66)/Be neutron radiation to assess DNA double-strand break (DSB) damage, cell viability, and cell cycle progression. The combination of AuNPs and neutron radiation induced higher levels of γ-H2AX foci and micronucleus formation compared to treatments with AuNPs or X-ray radiation alone. AuNPs alone reduced cellular kinetics and increased the accumulation of cells in the G2/M phase, suggesting a block of cell cycle progression. For cell proliferation, significant effects were only observed at the concentration of 50 μg/mL of AuNPs, while lower concentrations had no inhibitory effect. Further research is needed to quantify internalized AuNPs and correlate their concentration with the observed cellular effects to unravel the biological mechanisms of their radioenhancement.

Magnetic-Plasmonic Core-Shell Nanoparticles: Properties, Synthesis and Applications for Cancer Detection and Treatment

Nanoparticles have been widely used in cancer diagnostics and treatment research due to their unique properties. Magnetic nanoparticles are popular in imaging techniques due to their ability to alter the magnetization field around them. Plasmonic nanoparticles are mainly applied in cancer treatments like photothermal therapy due to their ability to convert light into heat. While these nanoparticles are popular among their respective fields, magnetic-plasmonic core-shell nanoparticles (MPNPs) have gained popularity in recent years due to the combined magnetic and optical properties from the core and shell. MPNPs have stood out in cancer theranostics as a multimodal platform capable of serving as a contrast agent for imaging, a guidable drug carrier, and causing cellular ablation through photothermal energy conversion. In this review, we summarize the different properties of MPNPs and the most common synthesis approaches. We particularly discuss applications of MPNPs in cancer diagnosis and treatment based on different mechanisms using the magnetic and optical properties of the particles. Lastly, we look into current challenges they face for clinical applications and future perspectives using MPNPs for cancer detection and therapy.

Studying the Effect of Reducing Agents on the Properties of Gold Nanoparticles and Their Integration into Hyaluronic Acid Hydrogels

Gold nanoparticles (Au NPs) are a promising target for research due to their small size and the resulting plasmonic properties, which depend, among other things, on the chosen reducer. This is important because removing excess substrate from the reaction mixture is problematic. However, Au NPs are an excellent component of various materials, enriching them with their unique features. One example is hydrogels, which provide a good, easily modifiable base for multiple applications such as cosmetics. For this purpose, various compounds, including hyaluronic acid (HA) and its derivatives, are distinguished by their high water-binding capacity and many characteristics resulting from their natural origin in organisms, including biocompatibility, biodegradability, and tissue regeneration. In this work Au NPs were synthesized using a green chemistry method, either by using onion extract as a reductant or chemically reducing them with sodium citrate. A complete characterization of the nanoparticles was carried out using the following methods: Fourier-Transform Infrared Spectroscopy (FT-IR), Electrophoretic (ELS), and Dynamic Light Scattering (DLS) as well as Transmission Electron Microscope (TEM) and Scanning Electron Microscope (SEM). Their antioxidant activity was also tested using the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH). The results showed that the synthesized nanoparticles enrich the hydrogels with antioxidant properties and new surface properties (depending on the reducing agent, they can be more hydrophilic or hydrophobic). Preliminary observations indicated low cytotoxicity of the nanomaterials in both liquid form and as a hydrogel component, as well as their lack of penetration through pig skin. The cosmetic properties of hydrogel masks were also confirmed, such as increasing skin hydration.

Preliminary Study on Lutetium-177 and Gold Nanoparticles: Apoptosis and Radiation Enhancement in Hepatic Cancer Cell Line

This study investigates a novel approach toward enhancing the efficacy of Lutetium-177 (Lu-177) radiopharmaceutical therapy by combining it with gold nanoparticles (AuNPs) in the HepG2 hepatic cancer cell line. Lu-177, known for its effective β radiation, also emits gamma rays at energies (113 keV and 208 keV) near the photoelectric absorption range, suggesting potential for targeted and localized radiation enhancement when used in conjunction with AuNPs. Thus, HepG2 cells were treated at two different activity levels (74 MBq and 148 MBq), with Lu-177 alone, with a combination of Lu-177 and AuNPs in two sizes (10 nm and 50 nm), while some received no treatment. Treatment efficacy was assessed by quantifying the radiation enhancement ratio (RER) and the apoptosis levels. The results reveal that combining Lu-177 with AuNPs significantly increases cell death and apoptosis compared to Lu-177 alone, with 10 nm AuNPs demonstrating superior effectiveness. Additionally, varying Lu-177 activity levels influenced the treatment outcomes, with higher activity levels further augmenting the therapeutic impact of combined therapy. These findings underscore the potential of utilizing Lu-177's beta, but also gamma, emissions, traditionally considered non-therapeutic, for localized radiation enhancement when combined with AuNPs. This novel strategy leverages Lu-177 as an internal irradiator to exploit gamma radiation for a targeted therapeutic advantage without requiring nanoparticle functionalization. The study provides a promising approach to improving radionuclide therapy and sets the stage for future research aimed at optimizing cancer treatments through the combined use of Lu-177 and AuNPs.

Electromagnetic field as a possible inhibitor of tumor invasion by declining E-cadherin/N-cadherin switching in triple negative breast cancer

Breast cancer has been recognized as the most common cancer affecting women. Extremely low-frequency electromagnetic field (ELF-EMF) exposure can influence cellular activities such as cell-cell junctions and metastasis. However, more research is required to determine these fields' underlying mechanisms of action. Since cadherin switching is an important process during EMT (epithelial-mesenchymal transition), in this study, cadherin switching was regarded as one of the probable mechanisms of the effect of ELF-EMFs on metastasis suppression. For five days, breast cells received a 1 Hz, 100mT ELF-EMF (2 h/day). Cell invasion and migration were assessed in vitro by the Scratch wound healing assay and Transwell culture chambers. The expression of E- and N-cadherin was assessed using real-time PCR, western blotting, and Immunocytochemistry. ELF-EMF dramatically reduced the migration and invasion of MDA-MB 231 malignant cells compared to sham exposure, according to the results of the scratch test and the Transwell invasion test. The mRNA and protein expression levels of E-cadherin showed an increase, while the N-cadherin expression was found with a decrease, in MDA-MB231 cells receiving 1 Hz EMF compared to sham exposure. E-cadherin's mRNA and protein expression levels were enhanced in MCF10A cells receiving 1 Hz EMF compared to sham exposure. ELF-EMF can be used as a method for the multifaceted treatments of invasive breast cancer.

Precision medicine in breast cancer: Targeting molecular subtypes with gold nanoparticle-loaded liposomes

PURPOSE

Breast cancer is a complex disease with several molecular subtypes that respond differently to therapy. This paper describes liposomes loaded with gold nanoparticles as a targeted drug delivery method in the rapidly developing precision breast cancer treatment area. The aim was to investigate the cytotoxicity level and cellular uptake using several breast cancer cell lines and a normal breast cell line.

MATERIALS AND METHODS

We synthesized gold nanoparticles incorporated in liposomes. Nanostructures were incubated with breast cancer cell lines of different subtypes. The analysis included MTT assay, flow cytometry and immunofluorescence.

RESULTS

Cell viability varied among different cancer cells. Moreover, the time- and concentration-dependent manner of viability change was observed. The internalization of liposomes with gold nanoparticles and nanoparticles alone determined different results depending on molecular breast cancer subtypes. The luminal B and triple-negative breast cancer cells demonstrated the highest resistance and sensitivity, respectively. The intensity of cells' interaction with the proposed nanostructures was observed in both cell lines. In this study, we compare the molecular subtypes of breast cancer and discuss how this novel method might improve the therapy success.

CONCLUSIONS

Our research sheds light on the possibility of new individualized treatments for breast cancer patients, opening the path for better results and a more detailed cancer therapy strategy.

Dynamic interactions in the tumor niche: how the cross-talk between CAFs and the tumor microenvironment impacts resistance to therapy

The tumor microenvironment (TME) is a complex ecosystem of cells, signaling molecules, and extracellular matrix components that profoundly influence cancer progression. Among the key players in the TME, cancer-associated fibroblasts (CAFs) have gained increasing attention for their diverse and influential roles. CAFs are activated fibroblasts found abundantly within the TME of various cancer types. CAFs contribute significantly to tumor progression by promoting angiogenesis, remodeling the extracellular matrix, and modulating immune cell infiltration. In order to influence the microenvironment, CAFs engage in cross-talk with immune cells, cancer cells, and other stromal components through paracrine signaling and direct cell-cell interactions. This cross-talk can result in immunosuppression, tumor cell proliferation, and epithelial-mesenchymal transition, contributing to disease progression. Emerging evidence suggests that CAFs play a crucial role in therapy resistance, including resistance to chemotherapy and radiotherapy. CAFs can modulate the tumor response to treatment by secreting factors that promote drug efflux, enhance DNA repair mechanisms, and suppress apoptosis pathways. This paper aims to understand the multifaceted functions of CAFs within the TME, discusses cross-talk between CAFs with other TME cells, and sheds light on the contibution of CAFs to therapy resistance. Targeting CAFs or disrupting their cross-talk with other cells holds promise for overcoming drug resistance and improving the treatment efficacy of various cancer types.

Assessing the gene silencing potential of AuNP-based approaches on conventional 2D cell culture versus 3D tumor spheroid

Three-dimensional (3D) cell culture using tumor spheroids provides a crucial platform for replicating tissue microenvironments. However, effective gene modulation via nanoparticle-based transfection remains a challenge, often facing delivery hurdles. Gold nanoparticles (AuNPs) with their tailored synthesis and biocompatibility, have shown promising results in two-dimensional (2D) cultures, nevertheless, they still require a comprehensive evaluation before they can reach its full potential on 3D models. While 2D cultures offer simplicity and affordability, they lack physiological fidelity. In contrast, 3D spheroids better capture in vivo conditions, enabling the study of cell interactions and nutrient distribution. These models are essential for investigating cancer behavior, drug responses, and developmental processes. Nevertheless, transitioning from 2D to 3D models demands an understanding of altered internalization mechanisms and microenvironmental influences. This study assessed ASO-AuNP conjugates for silencing the c-MYC oncogene in 2D cultures and 3D tumor spheroids, revealing distinctions in gene silencing efficiency and highlighting the microenvironment's impact on AuNP-mediated gene modulation. Herein, we demonstrate that increasing the number of AuNPs per cell by 2.6 times, when transitioning from a 2D cell model to a 3D spheroid, allows to attain similar silencing efficiencies. Such insights advance the development of targeted gene therapies within intricate tissue-like contexts.

Methodological and Cellular Factors Affecting the Magnitude of Breast Cancer and Normal Cell Radiosensitization Using Gold Nanoparticles

Purpose

Breast cancer (BC) is the most common malignant tumor in women, which most often originates from the epithelial tissue of the breast gland. One of the most recommended kinds of treatment is radiotherapy (RT), but irradiation (IR) can affect not only the cancer tumor but also the healthy tissue around it. Au nanoparticles (AuNPs) were proposed as a radiosensitizing agent for RT which would allow for lower radiation doses, reducing the negative radiation effects on healthy tissues. The main objective of the study is to assess the dependence on the radiosensitivity of BC (MDA-MB-231) and normal mammary gland epithelial cells (MCF12A) to ionizing radiation, caused by functionalized AuNPs under diverse conditions.

Methods

The viability, uptake, reactive oxygen species induction, and mitochondrial membrane potential in cells were analyzed applying a time and concentration-dependent manner. After different incubation times with AuNPs, cells were exposed to 2 Gy. The determination of radiation effect in combination with AuNPs was investigated using the clonogenic assay, p53, and γH2AX level, as well as, Annexin V staining.

Results

Our results highlighted the strong need for assessing the experimental conditions' optimization before the AuNPs will be implemented with IR. Moreover, results indicated that AuNPs did not act universally in cells.

Conclusion

AuNPs could be a promising tool as a radiotherapy sensitizing agent, but it should be specified and deeply investigated under what conditions it will be applied taking into consideration not only AuNPs modifications but also the model and experimental conditions.