Platinum Group Metals Nanoparticles in Breast Cancer Therapy

Abstract

Despite various methods currently used in cancer therapy, breast cancer remains the leading cause of morbidity and mortality worldwide. Current therapeutics face limitations such as multidrug resistance, drug toxicity and off-target effects, poor drug bioavailability and biocompatibility, and inefficient drug delivery. Nanotechnology has emerged as a promising approach to cancer diagnosis, imaging, and therapy. Several preclinical studies have demonstrated that compounds and nanoparticles formulated from platinum group metals (PGMs) effectively treat breast cancer. PGMs are chemically stable, easy to functionalise, versatile, and tunable. They can target hypoxic microenvironments, catalyse the production of reactive oxygen species, and offer the potential for combination therapy. PGM nanoparticles can be incorporated with anticancer drugs to improve efficacy and can be attached to targeting moieties to enhance tumour-targeting efficiency. This review focuses on the therapeutic outcomes of platinum group metal nanoparticles (PGMNs) against various breast cancer cells and briefly discusses clinical trials of these nanoparticles in breast cancer treatment. It further illustrates the potential applications of PGMNs in breast cancer and presents opportunities for future PGM-based nanomaterial applications in combatting breast cancer.

Keywords: breast cancer; cancer diagnosis and cancer therapy; drug delivery; nanoparticles; platinum group metals.

Figure 1

Advantages of nano-enabled anticancer treatment over traditional methods.

Figure 2

Examples of nanomedicines (created with BioRender.com).

Figure 3

PGMs common cancer applications. Computed tomography (CT), magnetic resonance (MR), photodynamic therapy (PDT), photothermal therapy (PTT), single-photon emission computed tomography (SPECT).

Figure 4

Pd-NPs biomedical applications. CT = computed tomography, MR = magnetic resonance, PTT = photothermal therapy, PDT = photodynamic therapy, SPECT = single-photon emission computed tomography.

Figure 5

Combination of medicinal plant species with palladium nanoparticles for anticancer and related biological studies involving optimisation conditions through various characterisation techniques. Reproduced with copyright permission from MDPI [86]. [Dynamic light scattering (DLS), Fourier transform-infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction spectroscopy (XRD)].

Scheme 1

Synthetic pathway for preparing Ru-based selenium nanoparticles (Ru-SeNPs). Reproduced with copyright permission from Elsevier [111].

Figure 6

(a–d) Tumour volume, tumour area, percentage of necrosis area, and coagulation necrosis of 4T1 tumour tissue sections of the non-treated and treated groups, respectively. The a* in Figure 6b signify that Magh-Rh₂Cit is statically non-significant. The arrows in (d) signify the pyknotic nuclei (white arrow), karyolysis (black arrow), karyorrhexis (arrowhead). Reproduced with copyright permission [130].

Figure 6

(a–d) Tumour volume, tumour area, percentage of necrosis area, and coagulation necrosis of 4T1 tumour tissue sections of the non-treated and treated groups, respectively. The a* in Figure 6b signify that Magh-Rh₂Cit is statically non-significant. The arrows in (d) signify the pyknotic nuclei (white arrow), karyolysis (black arrow), karyorrhexis (arrowhead). Reproduced with copyright permission [130].

Figure 7

(a) The synthetic procedure for IrO₂-GOx@HA NPs. (b) Mechanism of action of IrO₂-GOx@HA NP after binding to the CD44 receptor located on the tumour cell surface, followed by infiltration into the cell, triggering an in situ reaction facilitated by IrO₂ NPs and GOx. The arrow signifies the in-situ reaction mediated by IrO₂ NPs and GOx forms an amplifier to enhance the II type PDT mediated by IrO₂ NPs themselves. (c) Hypoxia areas were quantified using Image J software (https://imagej.net/ij/, accessed on 25 August 2024). Statistical significances were calculated via Student’s t-test, *** p < 0.001, ** p < 0.01, compared with the control group (d) Cancer volume changes in 14 days after various treatments. The groups are as follows: G 1 (Control), G 2 (PTT), G 3 (PDT), G 4 (PTT + PDT), G 5 (PTT + IrO₂-GOx@HA NPs), G 6 (PDT + IrO₂-GOx@HA NPs), and G 7 (PTT + PDT + IrO₂-GOx@HA NPs). Reproduced with copyright permission from Elsevier [161]. Where GOx is glucose oxidase, PDT is photodynamic therapy, PTT is photothermal therapy, and PVP is polyvinyl pyrrolidone.

Figure 8

(a) The chemical structure of the iridium(III)-cyanine complex. (b) The viability of 4T1 cells was assessed by culturing them with varying concentrations of IrCy NPs (0, 5, 10, 25, and 50 μM) followed by laser irradiation. (c) Changes in tumour volume over time under different treatments. (d) Tumour weight measured on the 14th day after PDT for each of the four groups. Reproduced with copyright permission from the American Chemical Society [169].