Photothermal effects of NaYF4:Yb,Er@PE3@Fe3O4 superparamagnetic nanoprobes in the treatment of melanoma

Inhibiting Osteolytic Breast Cancer Bone Metastasis by Bone-Targeted Nanoagent via Remodeling the Bone Tumor Microenvironment Combined with NIR-II Photothermal Therapy

Bone is one of the prone metastatic sites of patients with advanced breast cancer. The "vicious cycle" between osteoclasts and breast cancer cells plays an essential role in osteolytic bone metastasis from breast cancer. In order to inhibit bone metastasis from breast cancer, NIR-II photoresponsive bone-targeting nanosystems (CuP@PPy-ZOL NPs) are designed and synthesized. CuP@PPy-ZOL NPs can trigger the photothermal-enhanced Fenton response and photodynamic effect to enhance the photothermal treatment (PTT) effect and thus achieve synergistic anti-tumor effect. Meanwhile, they exhibit a photothermal enhanced ability to inhibit osteoclast differentiation and promote osteoblast differentiation, which reshaped the bone microenvironment. CuP@PPy-ZOL NPs effectively inhibited the proliferation of tumor cells and bone resorption in the in vitro 3D bone metastases model of breast cancer. In a mouse model of breast cancer bone metastasis, CuP@PPy-ZOL NPs combined with PTT with NIR-II significantly inhibited the tumor growth of breast cancer bone metastases and osteolysis while promoting bone repair to achieve the reversal of osteolytic breast cancer bone metastases. Furthermore, the potential biological mechanisms of synergistic treatment are identified by conditioned culture experiments and mRNA transcriptome analysis. The design of this nanosystem provides a promising strategy for treating osteolytic bone metastases.

Effectiveness of Gold Nanorods of Different Sizes in Photothermal Therapy to Eliminate Melanoma and Glioblastoma Cells

Gold nanorods are the most commonly used nanoparticles in photothermal therapy for cancer treatment due to their high efficiency in converting light into heat. This study aimed to investigate the efficacy of gold nanorods of different sizes (large and small) in eliminating two types of cancer cell: melanoma and glioblastoma cells. After establishing the optimal concentration of nanoparticles and determining the appropriate time and power of laser irradiation, photothermal therapy was applied to melanoma and glioblastoma cells, resulting in the highly efficient elimination of both cell types. The efficiency of the PTT was evaluated using several methods, including biochemical analysis, fluorescence microscopy, and flow cytometry. The dehydrogenase activity, as well as calcein-propidium iodide and Annexin V staining, were employed to determine the cell viability and the type of cell death triggered by the PTT. The melanoma cells exhibited greater resistance to photothermal therapy, but this resistance was overcome by irradiating cells at physiological temperatures. Our findings revealed that the predominant cell-death pathway activated by the photothermal therapy mediated by gold nanorods was apoptosis. This is advantageous as the presence of apoptotic cells can stimulate antitumoral immunity in vivo. Considering the high efficacy of these gold nanorods in photothermal therapy, large nanoparticles could be useful for biofunctionalization purposes. Large nanorods offer a greater surface area for attaching biomolecules, thereby promoting high sensitivity and specificity in recognizing target cancer cells. Additionally, large nanoparticles could also be beneficial for theranostic applications, involving both therapy and diagnosis, due to their superior detection sensitivity.

A dual-modal biosensor coupling cooperative catalysis strategy for sensitive detection of AFB1 in agri-products

Herein, the cooperative catalysis effect between nanocomposite (AgPd NPs/POD-M/PEI-rGO) and horseradish peroxidase (HRP) was applied for the fast and sensitive detection of aflatoxin B1 (AFB₁). Upon specific and competitive binding of HRP@DNA and AFB₁ to cDNA, the working electrode presented different catalytic capacities for supporting electrolytes (TMB and H₂O₂). In the redox mechanism of TMB and H₂O₂, HRP and nanocomposite effectively catalyzed the oxidization of TMB to form the one-electron oxidation intermediate TMB+, and contributed the electrical signals and absorbance signals. Electrochemistry and colorimetric analyses were successfully realized for AFB₁ detection with 0.2 pg/mL and 8 pg/mL of detection limits, respectively, which is much lower than that of traditional HPLC methods. Overall, this method had significant reliability and sensitivity, offering a promising potential for conveniently evaluating the quality of agri-products polluted with AFB₁. Moreover, this approach provides a new idea for fast and accurate detection of mycotoxin.

Photothermal ablation of murine melanomas by Fe3O4 nanoparticle clusters

Melanoma is one of the deadliest forms of cancer, for which therapeutic regimens are usually limited by the development of resistance. Here, we fabricated Fe3O4 nanoparticle clusters (NPCs), which have drawn widespread attention, and investigated their role in the treatment of melanoma by photothermal therapy (PTT). Scanning electron microscopy imaging shows that our synthesized NPCs are spherical with an average diameter of 329.2 nm. They are highly absorptive at the near-infrared wavelength of 808 nm and efficient at locally converting light into heat. In vitro experiments using light-field microscopy and cell viability assay showed that Fe3O4 NPCs, in conjunction with near-infrared irradiation, effectively ablated A375 melanoma cells by inducing overt apoptosis. Consistently, in vivo studies using BALB/c mice found that intratumoral administration of Fe3O4 NPCs and concomitant in situ exposure to near-infrared light significantly inhibited the growth of implanted tumor xenografts. Finally, we revealed, by experimental approaches including semi-quantitative PCR, western blot and immunohistochemistry, the heat shock protein HSP70 to be upregulated in response to PTT, suggesting this chaperone protein could be a plausible underlying mechanism for the observed therapeutic outcome. Altogether, our results highlight the promise of Fe3O4 NPCs as a new PTT option to treat melanoma.

Phenotypic Switching of B16F10 Melanoma Cells as a Stress Adaptation Response to Fe3O4/Salicylic Acid Nanoparticle Therapy

Melanoma is a melanocyte-derived skin cancer that has a high heterogeneity due to its phenotypic plasticity, a trait that may explain its ability to survive in the case of physical or molecular aggression and to develop resistance to therapy. Therefore, the therapy modulation of phenotypic switching in combination with other treatment modalities could become a common approach in any future therapeutic strategy. In this paper, we used the syngeneic model of B16F10 melanoma implanted in C57BL/6 mice to evaluate the phenotypic changes in melanoma induced by therapy with iron oxide nanoparticles functionalized with salicylic acid (SaIONs). The results of this study showed that the oral administration of the SaIONs aqueous dispersion was followed by phenotypic switching to highly pigmented cells in B16F10 melanoma through a cytotoxicity-induced cell selection mechanism. The hyperpigmentation of melanoma cells by the intra- or extracellular accumulation of melanic pigment deposits was another consequence of the SaIONs therapy. Additional studies are needed to assess the reversibility of SaIONs-induced phenotypic switching and the impact of tumor hyperpigmentation on B16F10 melanoma’s progression and metastasis abilities.

Cell-Released Magnetic Vesicles Capturing Metabolic Labeled Rare Circulating Tumor Cells Based on Bioorthogonal Chemistry

Capture of circulating tumor cells (CTCs) with high efficiency and high purity holds great value for potential clinical applications. Besides the existing problems of contamination from blood cells and plasma proteins, unknown/down-regulated expression of targeting markers (e.g., antigen, receptor, etc.) of CTCs have questioned the reliability and general applicability of current CTCs capture methodologies based on immune/aptamer-affinity. Herein, a cell-engineered strategy is designed to break down such barriers by employing the cell metabolism as the leading force to solve key problems. Generally, through an extracellular vesicle generation way, the cell-released magnetic vesicles inherited parent cellular membrane characteristics are produced, and then functionalized with dibenzoazacyclooctyne to target and isolate the metabolic labeled rare CTCs. This strategy offers good reliability and broader possibilities to capture different types of tumor cells, as proven by the capture efficiency above 84% and 82% for A549 and HepG2 cell lines as well as an extremely low detection limitation of 5 cells. Moreover, it enabled high purity enrichment of CTCs from 1 mL blood samples of tumor-bearing mice, only ≈5-757 white blood cells are non-specific caught, ignoring the potential phenotypic fluctuation associated with the cancer progression.

An Intelligent Biomimetic Nanoplatform for Holistic Treatment of Metastatic Triple-Negative Breast Cancer via Photothermal Ablation and Immune Remodeling

Metastasis is one of the main causes of failure in the treatment of triple-negative breast cancer (TNBC). Immunotherapy brings hope and opportunity to solve this challenge, while its clinical applications are greatly inhibited by the tumor immunosuppressive environment. Here, an intelligent biomimetic nanoplatform was designed based on dendritic large-pore mesoporous silica nanoparticles (DLMSNs) for suppressing metastatic TNBC by combining photothermal ablation and immune remodeling. Taking advantage of the ordered large-pore structure and easily chemically modified property of DLMSNs, the copper sulfide (CuS) nanoparticles with high photothermal conversion efficiency were in situ deposited inside the large pores of DLMSNs, and the immune adjuvant resiquimod (R848) was loaded controllably. A homogenous cancer cell membrane was coated on the surfaces of these DLMSNs, followed by conjugation with the anti-PD-1 peptide AUNP-12 through a polyethylene glycol linker with an acid-labile benzoic-imine bond. The thus-obtained AM@DLMSN@CuS/R848 was applied to holistically treat metastatic TNBC in vitro and in vivo. The data showed that AM@DLMSN@CuS/R848 had a high TNBC-targeting ability and induced efficient photothermal ablation on primary TNBC tumors under 980 nm laser irradiation. Tumor antigens thus generated and increasingly released R848 by response to the photothermal effect, combined with AUNP-12 detached from AM@DLMSN@CuS/R848 in the weakly acidic tumor microenvironment, synergistically exerted tumor vaccination, and T lymphocyte activation functions on immune remodeling to prevent TNBC recurrence and metastasis. Taken together, this study provides an intelligent biomimetic nanoplatform to enhance therapeutic outcomes in metastatic TNBC.

Applications of Nanomaterials for Theranostics of Melanoma

Melanoma is an aggressive form of skin cancer with a very high mortality rate. Early diagnosis of the disease, the utilization of more potent pharmacological agents, and more effective drug delivery systems are essential to achieve an optimal treatment plan. The applications of nanotechnology to improve therapeutic efficacy and early diagnosis for melanoma treatment have received great interest among researchers and clinicians. In this review, we summarize the recent progress of utilizing various nanomaterials for theranostics of melanoma. The key importance of using nanomaterials for theranostics of melanoma is to improve efficacy and reduce side effects, ensuring safe implementation in clinical use. As opposed to conventional in vitro diagnostic methods, in vivo medical imaging technologies have the advantages of being a type of non-invasive, real-time monitoring. Several common nanoparticles, including ultrasmall superparamagnetic iron oxide nanoparticles, silica nanoparticles, and carbon-based nanoparticles, have been applied to deliver chemotherapeutic agents for the theranostics of melanoma. The application of nanomaterials for theranostics in molecular imaging (MRI, PET, US, OI, etc.) plays an important role in targeting drug delivery of melanoma, by monitoring the distribution site of the molecular imaging probe and the therapeutic drug in the body in real-time. Hence, it is worthwhile to anticipate the approval of these nanomaterials for theranostics in molecular imaging by the US Food and Drug Administration in clinical trials.

Prussian blue-coated lanthanide-doped core/shell/shell nanocrystals for NIR-II image-guided photothermal therapy

Lanthanide-doped nanoparticles have long been stereotyped for optical luminescence bioimaging. However, they are known to be unable to produce therapeutic abilities. Here, we describe a lanthanide-based theranostic agent, namely, prussian blue (PB)-coated NaErF4@NaYF4@NaNdF4 core/shell/shell nanocrystals encapsulated in a phospholipid PEG micelle (PEG-CSS@PB), which showed switched imaging and hyperthermia abilities under distinct near infrared (NIR) light activation. The erbium (Er3+)-enriched inner core nanocrystals (NaErF4) enabled the emission of tissue-penetrating luminescence (1525 nm) in the second biological window (NIR-II, 1000-1700 nm), which endowed high-resolution optical imaging of the blood vessels and tumors under ∼980 nm excitation. High neodymium (Nd3+) concentrations in the epitaxial outer NaNdF4 shell introduced maximum cross relaxation processes that converted the absorbed NIR light (∼808 nm) into heat at high efficiencies, thus providing abilities for photothermal therapy (PTT). Importantly, the coated Prussian blue (PB) increased light absorption by about 10-fold compared to the composite free of PB, thus entailing a high light-to-heat conversion efficiency of ∼50.5%. This commensurated with that of well-established gold nanorods. As a result, the PEG-CSS@PB nanoparticles with MTT-determined low toxicities resulted in ∼80% death of HeLa cells at a dose of 600 μg mL-1 under 808 nm laser irradiance (1 W cm-2) for 10 min. Moreover, utilizing the same light dose, a single PTT treatment in tumor-bearing BALB/c mice shrunk the tumor size by ∼12-fold compared to the tumors without treatment. Our results, here, constituted a solid step forward to entitle lanthanide-based nanoparticles as theranostic agents in nanomedicine studies.