Potential In Photothermal Therapy Research Articles

Integrating photoluminescence, magnetism and thermal conversion for potential photothermal therapy and dual-modal bioimaging

Multifunctional nanocomposites (NCs) incorporating magnetic, luminescent and photothermal conversion properties are endowed with potential application in many fields such as imaging, tumor detection, drug delivery and therapy. Here, multifunctional MWCNTs-NaGdF4:Yb3+, Er3+, Eu3+ NCs, which offer the potential for integrated bioimaging and photothermal therapy (PTT) were fabricated by a facile hydrothermal method. The resulting sample exhibits uniform morphology, bright dual-modal luminescence and intrinsic paramagnetic properties. Under near-infrared laser excitation, NCs have excellent photothermal conversion properties. In addition, the MTT assay in HeLa cells shows that the NCs have good biocompatibility. Moreover, the up-conversion luminescence (UCL) imaging, X-ray computed tomography (CT) imaging and PTT in vitro of NCs were investigated. The results indicate that NCs can be used for dual-modal imaging-guided diagnose and PTT of cancer cells.

New Application of Old Material: Chinese Traditional Ink for Photothermal Therapy of Metastatic Lymph Nodes.

Finding a simple and effective strategy to eliminate tumor metastatic lymph nodes is highly desired in clinical tumor treatment. Herein, we reported a Chinese traditional ink (Hu-ink)-based treatment for photothermal therapy (PTT) of tumor metastatic lymph nodes. By simple dilution, stable Chinese traditional ink dispersion was obtained, which presents excellent photothermal effect because of its high absorption in near-infrared (NIR) region. Meanwhile, as revealed by staining and photoacoustic imaging, Hu-ink could transfer to nearby lymph nodes after directly injected into the primary tumors. Under the guidance of dual-modality mapping, the metastatic sentinel lymph nodes could be subsequently eliminated by NIR irradiation. The good biocompatibility of Hu-ink has also been verified by a series of experiments. Therefore, the Hu-ink-based treatment exhibits great potential for PTT of tumor metastatic lymph nodes in future clinical practice.

Aptavalve-gated Mesoporous Carbon Nanospheres image Cellular Mucin and provide On-demand Targeted Drug Delivery.

In this report, we present a mesoporous carbon nanosphere that can target drugs to tumors and image tumor biomarkers. A single-strand DNA (P0 aptamer) aptavalve was capped on the surface of doxorubicin-loaded oxide mesoporous carbon nanospheres (Dox-OMCN-P0) through π-π stacking for real-time imaging-guided on-demand targeting drug delivery. The Dox-OMCN-P0 could not only realize the detection of MUC1 tumor marker with a wide linear range (0.1 - 10.6 μmol/L) and a low detection limit (17.5 nmol) based on different apparatuses, but also achieve in-situ targeting imaging of cellular MUC1 concentration in vitro and in vivo via “off-on” fluorescence biosensing. Much attractively, as a real-time feedback of the diagnostic/imaging outcomes, Dox-OMCN-P0 accomplished the on-demand targeting drug delivery in quantitative response to MUC1. Controllable chemotherapy with sustained release and pH-sensitiveness, together with the potential photothermal therapy, were also clearly demonstrated. This is a simple but advanced platform, which could well achieve the real-time switchable imaging of cellular mucin for targeting cancer therapy.

A multi-functional nanoplatform for efficacy tumor theranostic applications

Nanomaterials with multiple functions have become more and more popular in the domain of cancer research. MoS2 has a great potential in photothermal therapy, X-ray/CT imaging and drug delivery. In this study, a water soluble MoS2 nanosystem (MoS2-PEG) was synthesized and explored in drug delivery, photothermal therapy (PTT) and X-ray imaging. Doxorubicin (DOX) was loaded onto MoS2-PEG with a high drug loading efficiency (~69%) and obtained a multifunctional drug delivery system (MoS2-PEG/DOX). As the drug delivery, MoS2-PEG/DOX could efficiently cross the cell membranes, and escape from the endosome via NIR light irradiation, lead to more apoptosis in MCF-7 cells, and afford higher antitumor efficacy without obvious toxic effects to normal organs owing to its prolonged blood circulation and 11.6-fold higher DTX uptake of tumor than DOX. Besides, MoS2-PEG/DOX not only served as a drug delivery system, but also as a powerful PTT agent for thermal ablation of tumor and a strong X-ray contrast agent for tumor diagnosis. In the in vitro and in vivo studies, MoS2-PEG/DOX exhibited excellent tumor-targeting efficacy, outstanding synergistic anti-cancer effect of photothermal and chemotherapy and X-ray imaging property, demonstrating that MoS2-PEG/DOX had a great potential for simultaneous diagnosis and photothermal-chemotherapy in cancer treatment.

Recent advances in different modal imaging-guided photothermal therapy.

Photothermal therapy (PTT) has recently attracted considerable attention owing to its controllable treatment process, high tumour eradication efficiency and minimal side effects on non-cancer cells. PTT can melt cancerous cells by localising tissue hyperthermia induced by internalised therapeutic agents with a high photothermal conversion efficiency under external laser irradiation. Numerous invitro and invivo studies have shown the significant potential of PTT to treat tumours in future practical applications. Unfortunately, the lack of visualisation towards agent delivery and internalisation, as well as imaging-guided comprehensive evaluation of therapeutic outcome, limits its further application. Developments in combined photothermal therapeutic nanoplatforms guided by different imaging modalities have compensated for the major drawback of PTT alone, proving PTT to be a promising technique in biomedical applications. In this review, we introduce recent developments in different imaging modalities including single-modal, dual-modal, triple-modal and even multi-modal imaging-guided PTT, together with imaging-guided multi-functional theranostic nanoplatforms.

Elimination of epithelial-like and mesenchymal-like breast cancer stem cells to inhibit metastasis following nanoparticle-mediated photothermal therapy.

Increasing evidence suggesting breast cancer stem cells (BCSCs) drive metastasis and evade traditional therapies underscores a critical need to exploit the untapped potential of nanotechnology to develop innovative therapies that will significantly improve patient survival. Photothermal therapy (PTT) to induce localized hyperthermia is one of few nanoparticle-based treatments to enter clinical trials in human cancer patients, and has recently gained attention for its ability to induce a systemic immune response targeting distal cancer cells in mouse models. Here, we first conduct classic cancer stem cell (CSC) assays, both invitro and in immune-compromised mice, to demonstrate that PTT mediated by highly crystallized iron oxide nanoparticles effectively eliminates BCSCs in translational models of triple negative breast cancer. PTT invitro preferentially targets epithelial-like ALDH+BCSCs, followed by mesenchymal-like CD44+/CD24- BCSCs, compared to bulk cancer cells. PTT inhibits BCSC self-renewal through reduction of mammosphere formation in primary and secondary generations. Secondary implantation in NOD/SCID mice reveals the ability of PTT to impede BCSC-driven tumor formation. Next, we explore the translational potential of PTT using metastatic and immune-competent mouse models. PTT to inhibit BCSCs significantly reduces metastasis to the lung and lymph nodes. In immune-competent BALB/c mice, PTT effectively eliminates ALDH+BCSCs. These results suggest the feasibility of incorporating PTT into standard clinical treatments such as surgery to enhance BCSC destruction and inhibit metastasis, and the potential of such combination therapy to improve long-term survival in patients with metastatic breast cancer.

Void Engineering in Metal–Organic Frameworks via Synergistic Etching and Surface Functionalization

The rational design and engineering of metal–organic framework (MOF) crystals with hollow features has been used for various applications. Here, a top‐down strategy is established to construct hollow MOFs via synergistic etching and surface functionalization by using phenolic acid. The macrosized cavities are created inside various types of MOFs without destroying the parent crystalline framework, as evidenced by electron microscopy and X‐ray diffraction. The modified MOFs are simultaneously coated by metal–phenolic films. This coating endows the MOFs with the additional functionality of responding to near infrared irradiation to produce heat for potential photothermal therapy applications.

Tellurium platinate nanowires for photothermal therapy of cancer cells.

Among the most celebrated modes of cancer treatment, photothermal therapy has been the most promising tool over the past few years. In spite of the introduction of many novel nanomaterials for photothermal therapy, there is still plenty of room for exploration of naïve materials. We have explored the photothermal properties of metal chalcogenides, namely tellurium platinate nanowires (TePt NWrs), in this work. Upon irradiation with a laser (Ti:sapphire laser, 808 nm) the temperature of the aqueous suspension of TePt NWrs was found to increase to ∼62 °C from room temperature at optimum concentrations. This was due to the stability and high photothermal transduction efficiency of nanorods (NRs) i.e.∼47%. The power to ablate tumor cells was studied using A549 cells and tumor grafted experimental mice models. After an initial exposure for 10 min (808 nm laser at 1 W cm-2), the cells were killed mainly by the process of apoptosis as confirmed by a flow cytometry assisted cell sorting system (FACS; PI-FITC-Annexin V staining). Tumor growth was significantly reduced after photothermal therapy via a combination of TePt NRs and laser, thus proving the importance of this new nanomaterial for cancer photothermal therapy. The current approach has introduced a highly potential photothermal therapy method for applications in the medical world in the near future.

Tumor‐Penetrating Nanotherapeutics Loading a Near‐Infrared Probe Inhibit Growth and Metastasis of Breast Cancer

The tumor growth and metastasis is the leading reason for the high mortality of breast cancer. Herein, it is first reported a deep tumor‐penetrating photothermal nanotherapeutics loading a near‐infrared (NIR) probe for potential photothermal therapy (PTT) of tumor growth and metastasis of breast cancer. The NIR probe of 1,1‐dioctadecyl‐3,3,3,3‐tetramethylindotricarbocyanine iodide (DiR), a lipophilicfluorescent carbocyanine dye with strong light‐absorbing capability, is entrapped into the photothermal nanotherapeutics for PTT application. The DiR‐loaded photothermal nanotherapeutics (DPN) is homogeneous nanometer‐sized particles with the mean diameter of 24.5 ± 4.1 nm. Upon 808 nm laser irradiation, DPN presents superior production of thermal energy than free DiR both in vitro and in vivo. The cell proliferation and migration activities of metastatic 4T1 breast cancer cells are obviously inhibited by DPN in combination with NIR irradiation. Moreover, DPN can induce a higher accumulation in tumor and penetrate into the deep interior of tumor tissues. The in vivo PTT measurements indicate that the growth and metastasis of breast cancer are entirely inhibited by a single treatment of DPN with NIR irradiation. Therefore, the deep tumor‐penetrating DPN can provide a promising strategy for PTT of tumor progression and metastasis of breast cancer.

Construction of stable chainlike Au nanostructures via silica coating and exploration for potential photothermal therapy.

A facile one-pot approach is successfully developed to construct the stable Au nanochains with silica shell via self-assembly and classical Stöber process. The resulting Au chain@SiO2 nanoparticles holds great promise for serving as a safe, reusable, and high-performance photothermal agent against cancer.

Plasmon-Mediated Embedding of Nanoparticles in a Polymer Matrix: Nanocomposites Patterning, Writing, and Defect Healing

Plasmonics, as an emerging field, aims to exploit the unique optical properties of metallic nanostructures to enable routing and active manipulation of light on the nanoscale. Plasmonic heating is a phenomenon, which is recently recognized for its potential in photothermal therapy. Here we show the first proof-of-concept experiment based on plasmonic heating for selective and precise embedding of nanoparticles in a polymeric matrix. We demonstrate a unique way for in situ fabrication of nanocomposites in different forms including patterning, writing, and defect healing in a controlled manner along with crystallinity control through light irradiation.

Specific Cell Targeting with Nanobody Conjugated Branched Gold Nanoparticles for Photothermal Therapy

Branched gold nanoparticles are potential photothermal therapy agents because of their large absorption cross section in the near-infrared window. Upon laser irradiation they produce enough heat to destroy tumor cells. In this work, branched gold nanoparticles are biofunctionalized with nanobodies, the smallest fully functional antigen-binding fragments evolved from the variable domain, the VHH, of a camel heavy chain-only antibody. These nanobodies bind to the HER2 antigen which is highly expressed on breast and ovarian cancer cells. Flow cytometric analysis and dark field images of HER2 positive SKOV3 cells incubated with anti-HER2 conjugated branched gold nanoparticles show specific cell targeting. Laser irradiation studies reveal that HER2 positive SKOV3 cells exposed to the anti-HER2 targeted branched gold nanoparticles are destroyed after five minutes of laser treatment at 38 W/cm(2) using a 690 nm continuous wave laser. Starting from a nanoparticle optical density of 4, cell death is observed, whereas the control samples, nanoparticles with anti-PSA nanobodies, nanoparticles only, and laser only, do not show any cell death. These results suggest that this new type of bioconjugated branched gold nanoparticles are effective antigen-targeted photothermal therapeutic agents for cancer treatment.

Ultrasmall Reduced Graphene Oxide with High Near-Infrared Absorbance for Photothermal Therapy

We developed nanosized, reduced graphene oxide (nano-rGO) sheets with high near-infrared (NIR) light absorbance and biocompatibility for potential photothermal therapy. The single-layered nano-rGO sheets were ∼20 nm in average lateral dimension, functionalized noncovalently by amphiphilic PEGylated polymer chains to render stability in biological solutions and exhibited 6-fold higher NIR absorption than nonreduced, covalently PEGylated nano-GO. Attaching a targeting peptide bearing the Arg-Gly-Asp (RGD) motif to nano-rGO afforded selective cellular uptake in U87MG cancer cells and highly effective photoablation of cells in vitro. In the absence of any NIR irradiation, nano-rGO exhibited little toxicity in vitro at concentrations well above the doses needed for photothermal heating. This work established nano-rGO as a novel photothermal agent due to its small size, high photothermal efficiency, and low cost as compared to other NIR photothermal agents including gold nanomaterials and carbon nanotubes.

Gold decorated NaYF4:Yb,Er/NaYF4/silica (core/shell/shell) upconversion nanoparticles for photothermal destruction of BE(2)-C neuroblastoma cells

Gold decorated NaYF4:Yb,Er/NaYF4/silica (core/shell/shell) upconversion (UC) nanoparticles (~70–80 nm) were synthesized using tetraethyl orthosilicate and chloroauric acid in a one-step reverse microemulsion method. Gold nanoparticles (~6 nm) were deposited on the surface of silica shell of these core/shell/shell nanoparticles. The total upconversion emission intensity (green, red, and blue) of the core/shell/shell nanoparticles decreased by ~31% after Au was deposited on the surface of silica shell. The upconverted green light was coupled with the surface plasmon of Au leading to rapid heat conversion. These UC/silica/Au nanoparticles were very efficient to destroy BE(2)-C cancer cells and showed strong potential in photothermal therapy.

Quantification of the selective retention of palladium octabutoxynaphthalocyanine, a potential photothermal drug, in mouse tissues

Palladium octabutoxynaphthalocyanine (PdNc(OBu) 8) is a potential photothermal therapy (PTT) agent, absorbing strongly in the near-infrared region with no ability to induce photodynamic-type sensitisation (unlike many related napthalocyanines). We report here on the application of high pressure liquid chromatography (HPLC) with near-infrared absorption detection for the determination of the tissue accumulation and clearance of PdNc(OBu) 8 in a tumour-bearing mouse model (Balb/c mice with EMT6 carcinoma tumour). Due to its insolubility in aqueous-based solvents, the drug was delivered intraperitoneally in a Cremophor-containing vehicle. Good selective accumulation of the drug into the tumour versus muscle or skin is observed, with the best combination of selectivity and tumour concentration occurring at 24–72 h after drug administration. Clearance times are quite long. Comparison with other similar drugs as reported in the literature indicates that the Cremophor-containing vehicle is likely in large part responsible for the observed pharmacokinetic behaviour. This drug shows potential for PTT and will be investigated further for therapy in this animal model.