A Laser-Activated Biocompatible Theranostic Nanoagent for Targeted Multimodal Imaging and Photothermal Therapy

Drug delivery particles for targeted imaging-guided photothermal/chemotherapy synergy cancer therapy

The early stage of pancreatic cancer is asymptomatic and the treatment effect is not ideal. The progression to the advanced stage leads to a close relationship between mortality and morbidity. Therefore, there is an urgent need to develop precise and efficient therapeutic strategies to combat pancreatic cancer. In this study, we introduce a near-infrared (NIR) targeted drug delivery nanoparticle for ultrasound (US) imaging to guide magnetothermal/chemotherapy synergistic treatment of pancreatic cancer. Carboxylated polylactic acid (PLGA-PEG-COOH) serves as the structure of the nanoparticles, specifically binding the RGD cyclic peptide for pancreatic cancer targeting activity and promoting tumor aggregation of the nanoparticles. NIR-induced superparamagnetic iron oxide (SPIO) nanoparticles convert near-infrared light into thermal energy, triggering vaporization of perfluoropentane (PFH) droplets to generate PFH bubbles that enhance US imaging and help load doxorubicin (DOX), which are released from nanoparticles. SPIO can also be used for thermal ablation of tumors to improve therapeutic effect in treating pancreatic cancer. The results show that the targeted particles mediated by NIR have the characteristics of targeted drug delivery imaging. The microspheres exhibit strong acoustic and near-infrared responsiveness. Cell proliferation experiments showed that IR-mediated PFH-DOX@PLGA/SPIO-RGD NPs (RNPs) had a higher inhibitory effect on cell proliferation. Animal experiments have shown that RNPS can accumulate highly in the tumor area and show good therapeutic effect. In conclusion, this nanotherapeutic particle is a very promising targeted image-guided photothermal/chemotherapeutic synergistic tumor therapy strategy.

Diagnosis and treatment status of inoperable locally advanced breast cancer and the application value of inorganic nanomaterials

Locally advanced breast cancer (LABC) is a heterogeneous group of breast cancer that accounts for 10-30% of breast cancer cases. Despite the ongoing development of current treatment methods, LABC remains a severe and complex public health concern around the world, thus prompting the urgent requirement for innovative diagnosis and treatment strategies. The primary treatment challenges are inoperable clinical status and ineffective local control methods. With the rapid advancement of nanotechnology, inorganic nanoparticles (INPs) exhibit a potential application prospect in diagnosing and treating breast cancer. Due to the unique inherent characteristics of INPs, different functions can be performed via appropriate modifications and constructions, thus making them suitable for different imaging technology strategies and treatment schemes. INPs can improve the efficacy of conventional local radiotherapy treatment. In the face of inoperable LABC, INPs have proposed new local therapeutic methods and fostered the evolution of novel strategies such as photothermal and photodynamic therapy, magnetothermal therapy, sonodynamic therapy, and multifunctional inorganic nanoplatform. This article reviews the advances of INPs in local accurate imaging and breast cancer treatment and offers insights to overcome the existing clinical difficulties in LABC management.

Sonodynamic and sonomechanical effect on cellular stemness and extracellular physicochemical environment to potentiate chemotherapy

BACKGROUND

Hypoxia-activated prodrug (HAP) is a promising candidate for highly tumor-specific chemotherapy. However, the oxygenation heterogeneity and dense extracellular matrix (ECM) of tumor, as well as the potential resistance to chemotherapy, have severely impeded the resulting overall efficacy of HAP.

RESULTS

A HAP potentiating strategy is proposed based on ultrasound responsive nanodroplets (PTP@PLGA), which is composed of protoporphyrin (PpIX), perfluoropropane (PFP) and a typical HAP, tirapazamine (TPZ). The intense vaporization of PFP upon ultrasound irradiation can magnify the sonomechanical effect, which loosens the ECM to promote the penetration of TPZ into the deep hypoxic region. Meanwhile, the PpIX enabled sonodynamic effect can further reduce the oxygen level, thus activating the TPZ in the relatively normoxic region as well. Surprisingly, abovementioned ultrasound effect also results in the downregulation of the stemness of cancer cells, which is highly associated with drug-refractoriness.

CONCLUSIONS

This work manifests an ideal example of ultrasound-based nanotechnology for potentiating HAP and also reveals the potential acoustic effect of intervening cancer stem-like cells.

Current trends in gas-synergized phototherapy for improved antitumor theranostics

Phototherapy, such as photothermal therapy (PTT) and photodynamic therapy (PDT), has been considered an elegant solution to eradicate tumors due to its minimal invasiveness and low systemic toxicity. Nevertheless, it is still challenging for phototherapy to achieve ideal outcomes and clinical translation due to its inherent drawbacks. Owing to the unique biological functions, diverse gases have attracted growing attention in combining with phototherapy to achieve super-additive therapeutic effects. Specifically, gases such as nitric oxide (NO), carbon monoxide (CO), and hydrogen sulfide (H2S) have been proven to kill tumor cells by inducing mitochondrial damage in synergy with phototherapy. Additionally, several gases not only enhance the thermal damage in PTT and the reactive oxygen species (ROS) production in PDT but also improve the tumor accumulation of photoactive agents. The inflammatory responses triggered by hyperthermia in PTT are also suppressed by the combination of gases. Herein, we comprehensively review the latest studies on gas-synergized phototherapy for cancer therapy, including (1) synergistic mechanisms of combining gases with phototherapy; (2) design of nanoplatforms for gas-synergized phototherapy; (3) multimodal therapy based on gas-synergized phototherapy; (4) imaging-guided gas-synergized phototherapy. Finally, the current challenges and future opportunities of gas-synergized phototherapy for tumor treatment are discussed. STATEMENT OF SIGNIFICANCE: 1. The novelty and significance of the work with respect to the existing literature. (1) Strategies to design nanoplatforms for gas-synergized anti-tumor phototherapy have been summarized for the first time. Meanwhile, the integration of various imaging technologies and therapy modalities which endow these nanoplatforms with advanced theranostic capabilities has been summarized. (2) The mechanisms by which gases synergize with phototherapy to eradicate tumors are innovatively and comprehensively summarized. 2. The scientific impact and interest. This review elaborates current trends in gas-synergized anti-tumor phototherapy, with special emphases on synergistic anti-tumor mechanisms and rational design of therapeutic nanoplatforms to achieve this synergistic therapy. It aims to provide valuable guidance for researchers in this field.

Undifferentially Expressed CXXC5 as a Transcriptionally Regulatory Biomarker of Breast Cancer

This work hypothesizes that some genes undergo radically changed transcription regulations (TRs) in breast cancer (BC), but don't show differential expressions for unknown reasons. The TR of a gene is quantitatively formulated by a regression model between the expression of this gene and multiple transcription factors (TFs). The difference between the predicted and real expression levels of a gene in a query sample is defined as the mqTrans value of this gene, which quantitatively reflects its regulatory changes. This work systematically screens the undifferentially expressed genes with differentially expressed mqTrans values in 1036 samples across five datasets and three ethnic groups. This study calls the 25 genes satisfying the above hypothesis in at least four datasets as dark biomarkers, and the strong dark biomarker gene CXXC5 (CXXC Finger Protein 5) is even supported by all the five independent BC datasets. Although CXXC5 does not show differential expressions in BC, its transcription regulations show quantitative associations with BCs in diversified cohorts. The overlapping long noncoding RNAs (lncRNAs) may have contributed their transcripts to the expression miscalculations of dark biomarkers. The mqTrans analysis serves as a complementary view of the transcriptome-based detections of biomarkers that are ignored by many existing studies.

Recent Advancements and Strategies for Overcoming the Blood-Brain Barrier Using Albumin-Based Drug Delivery Systems to Treat Brain Cancer, with a Focus on Glioblastoma

Glioblastoma multiforme (GBM) is a highly aggressive malignant tumor, and the most prevalent primary malignant tumor affecting the brain and central nervous system. Recent research indicates that the genetic profile of GBM makes it resistant to drugs and radiation. However, the main obstacle in treating GBM is transporting drugs through the blood-brain barrier (BBB). Albumin is a versatile biomaterial for the synthesis of nanoparticles. The efficiency of albumin-based delivery systems is determined by their ability to improve tumor targeting and accumulation. In this review, we will discuss the prevalence of human glioblastoma and the currently adopted treatment, as well as the structure and some essential functions of the BBB, to transport drugs through this barrier. We will also mention some aspects related to the blood-tumor brain barrier (BTBB) that lead to poor treatment efficacy. The properties and structure of serum albumin were highlighted, such as its role in targeting brain tumors, as well as the progress made until now regarding the techniques for obtaining albumin nanoparticles and their functionalization, in order to overcome the BBB and treat cancer, especially human glioblastoma. The albumin drug delivery nanosystems mentioned in this paper have improved properties and can overcome the BBB to target brain tumors.

GLUT-Targeting Phototherapeutic Nanoparticles for Synergistic Triple Combination Cancer Therapy

The combination of multimodal therapies into one nanocarrier system is promising for its potential to enhance treatment performance by overcoming the efficacy problems encountered in conventional monomodal therapy. In this study, targeted and multimodal therapeutic hybrid nanocarriers are fabricated for breast cancer treatments. In this context, the synthesized gold nanorods (AuNRd), photothermal therapy (PTT) agent, are coated with doxorubicin (DOX) conjugated, targeted, and biocompatible tetrablock glycopeptide (P(DMAEMA-b-HMBAMA-b-FrucMA)-b-P(Lys)/DOX, P-DOX) polymer. Here, fructose-based (Fruc) glycopeptide polymer enhances cellular uptake into breast cancer through GLUT5. A photosensitizer molecule, indocyanine green (ICG), was loaded into the particles to provide photodynamic therapy (PDT) upon NIR light at 808 nm. In the final step of the fabrication, the polymer-coated nanoparticles are integrated with antisense ISIS5132 oligonucleotides to prevent apoptotic resistance of cells against drug molecules. The biocompatibility and therapeutic efficacy of the nanoparticles are evaluated on both human normal skin fibroblast cell (CCD-1079Sk) and human breast cancer cell (MCF7) lines. These multimodal therapeutic AuNRd@P-DOX/ICG/ISIS5132 nanoparticles demonstrate an efficient triple synergistic effect of chemo-/PTT/PDT, which is desired for breast cancer treatment. We believe that this promising multimodal therapeutic nanoparticle system can promote the further clinical application in the treatment of breast cancer and can also be adapted to other types of cancer.

Integration of Silica Nanorattles with Manganese-Doped In2S3/InOOH to Enable Ultrasound-Mediated Tumor Theranostics

As a result of their radiation-free nature and deep-penetration ability, tumor theranostics mediated by ultrasound have become increasingly recognized as a modality with high potential for translation into clinical cancer treatment. The effective integration of ultrasound imaging and sonodynamic therapy (SDT) into one nanoplatform remains an enormous challenge yet to be fully resolved. Here, a novel theranostic system, consisting of rattle-type SiO₂ (r-SiO₂) loaded with Mn-doped In₂S₃/InOOH (SMISO), was designed and synthesized to enable an improved ultrasound imaging-guided therapy. With Mn-doped In₂S₃/InOOH (MISO) and a heterojunction structure, this novel sonosensitizer facilitates the generation of reactive oxygen species (ROS) for SDT. By coupling interfaces between the shell and core in rattle-type SiO₂, multiple reflections/scattering are generated, while MISO has high acoustic impedance. By integrating r-SiO₂ and MISO, the SMISO composite nanoparticles (NPs) increase the acoustic reflection and provide enhanced contrast for ultrasound imaging. Through the effective accumulation in tumors, which was monitored by B-mode ultrasound imaging in vivo, SMISO composite NPs effectively inhibited tumor growth without adverse side effects under ultrasound irradiation treatment. This work therefore provides a new approach to integrate a novel gas-free ultrasound contrast agent and a semiconductor sonosensitizer for cancer theranostics.

Advances in Single-component inorganic nanostructures for photoacoustic imaging guided photothermal therapy

Phototheranostic based on photothermal therapy (PTT) and photoacoustic imaging (PAI), as one of avant-garde medical techniques, have sparked growing attention because it allows noninvasive, deeply penetrative, and highly selective and effective therapy. Among a variety of phototheranostic nanoagents, single-component inorganic nanostructures are found to be novel and attractive PAI and PTT combined nanotheranostic agents and received tremendous attention, which not only exhibit structural controllability, high tunability in physiochemical properties, size-dependent optical properties, high reproducibility, simple composition, easy functionalization, and simple synthesis process, but also can be endowed with multiple therapeutic and imaging functions, realizing the superior therapy result along with bringing less foreign materials into body, reducing systemic side effects and improving the bioavailability. In this review, according to their synthetic components, conventional single-component inorganic nanostructures are divided into metallic nanostructures, metal dichalcogenides, metal oxides, carbon based nanostructures, upconversion nanoparticles (UCNPs), metal organic frameworks (MOFs), MXenes, graphdiyne and other nanostructures. On the basis of this category, their detailed applications in PAI guide PTT of tumor treatment are systematically reviewed, including synthesis strategies, corresponding performances, and cancer diagnosis and therapeutic efficacy. Before these, the factors to influence on photothermal effect and the principle of in vivo PAI are briefly presented. Finally, we also comprehensively and thoroughly discussed the limitation, potential barriers, future perspectives for research and clinical translation of this single-component inorganic nanoagent in biomedical therapeutics.

Multifunctional theragnostic ultrasmall gold nanodot-encapsuled perfluorocarbon nanodroplets for laser-focused ultrasound sequence irradiation (LFSI)-based enhanced tumor ablation

Despite the substantial potential of focused ultrasound therapy, its efficacy in cancer therapy has been limited due to the high cavitation threshold and safety concerns regarding the use of high-intensity energy pulses. Here, ultrasmall Au nanodot-loaded PEG-modified perfluorocarbon nanodroplets (Au-PFCnDs) were prepared and used as a therapeutic enhancer. A LFSI method was designed to achieve enhanced tumor ablation at a mild focused ultrasound (FUS) energy pulse with the assistance of the instinct photothermal effect of intratumor-permeable ultrasmall Au nanodots under 808 nm NIR laser irradiation. In addition to their therapeutic function, Au-PFCnDs can also generate multimodal images to provide information for tumor surveillance and treatment guidance. The experimental results also showed that the cRGD-targeted Au-PFCnDs could be more efficiently delivered into the tumor and selectively destroy tumors with no observable side effects on normal tissue under LFSI treatment.

'Mito-Bomb': a novel mitochondria-targeting nanosystem for ferroptosis-boosted sonodynamic antitumor therapy

Mitochondria play an important role in regulating tumor cell death and metabolism so that they can be potential therapeutic targets. Sonodynamic therapy (SDT) represents an attractive antitumor method that induces apoptosis by producing highly toxic reactive oxygen species (ROS). Mitochondria-targeting SDT can cause oxidative damage and improve the efficiency of tumor therapy. However, due to the nonselective distribution of nanosystems and the anti-apoptotic mechanism of cancer cells, the therapeutic effect of SDT is not ideal. Therefore, we proposed a novel mitochondria-targeting nanosystem (‘Mito-Bomb’) for ferroptosis-boosted SDT. Sonosensitizer IR780 and ferroptosis activator RSL-3 were both encapsulated in biocompatible poly(lactic‐co‐glycolic acid) (PLGA) nanoparticles to form ‘Mito-Bomb’ (named IRP NPs). IR780 in this nanosystem was used to mediate mitochondria-targeting SDT. RSL-3 inhibited the activity of GPX4 in the antioxidant system to induce ferroptosis of tumor cells, which could rewire tumor metabolism and make tumor cells extremely sensitive to SDT-induced apoptosis. Notably, we also found that RSL-3 can inhibit hypoxia inducible factor-1α (HIF-1α) and induce ROS production to improve the efficacy of SDT to synergistically antitumor. RSL-3 was applied as a ‘One-Stone-Three-Birds’ agent for cooperatively enhanced SDT against triple-negative breast cancer. This study presented the first example of RSL-3 boosting mitochondria-targeting SDT as a ferroptosis activator. The ‘Mito-Bomb’ biocompatible nanosystem was expected to become an innovative tumor treatment method and clinical transformation.

Recent Progress Toward Imaging Application of Multifunction Sonosensitizers in Sonodynamic Therapy

Sonodynamic therapy (SDT) is a rapidly developing non-surgical therapy that initiates sensitizers’ catalytic reaction using ultrasound, showing great potential for cancer treatment due to its high safety and non-invasive nature. In addition, recent research has found that using different diagnostic and therapeutic methods in tandem can lead to better anticancer outcomes. Therefore, as essential components of SDT, sonosensitizers have been extensively explored to optimize their functions and integrate multiple medical fields. The review is based on five years of articles evaluating the combined use of SDT and imaging in treating cancer. By developing multifunctional sonosensitive particles that combine imaging and sonodynamic therapy, we have integrated diagnosis into the treatment of precision medicine applications, improving SDT cell uptake and antitumor efficacy utilizing different tumour models. This paper describes the imaging principle and the results of cellular and animal imaging of the multifunctional sonosensitizers. Efforts are made in this paper to provide data and design references for future SDT combined imaging research and clinical application development and to provide offer suggestions.

Advances and prospects of ultrasound targeted drug delivery systems using biomaterial-modified micro/nanobubbles for tumor therapy

The incidence of malignant tumors is rising rapidly and tends to be in the younger, which has been one of the most important factors endangering the safety of human life. Ultrasound micro/nanobubbles, as a noninvasive and highly specific antitumor strategy, can reach and destroy tumor tissue through their effects of cavitation and acoustic perforation under the guidance of ultrasound. Meanwhile, micro/nanobubbles are now used as a novel drug carrier, releasing drugs at a target region, especially on the prospects of biomaterial-modified micro/nanobubbles as a dual modality for drug delivery and therapeutic monitoring. and successful evaluation of the sonoporation mechanism(s), ultrasound parameters, drug type and dose will need to be addressed before translating this technology for clinical use. Therefore, this paper collects the literature on the experimental and clinical studies of ultrasound biomaterial-modified micro/nanobubbles therapy in vitro and in vivo in recent years.

pH-Responsive Nanoparticles for Delivery of Paclitaxel to the Injury Site for Inhibiting Vascular Restenosis

A high incidence of restenosis has been reported at the site of inflammation following angioplasty and stent implantation. The anti-proliferative drug paclitaxel (PTX) could help to reduce inflammation and restenosis; however, it has poor water solubility and serious adverse side effects at high doses. Given the presence of metabolic acidosis at the site of inflammation, we hypothesized that nanoparticles that are responsive to low pH could precisely release the loaded drug at the target site. We successfully constructed pH-responsive poly(D, L-lactic-co-glycolic acid) (PLGA) nanoparticles loaded with PTX and NaHCO3 as a pH-sensitive therapeutic agent (PTX-NaHCO3-PLGA NPs). The NPs exhibited remarkable pH sensitivity and a good safety profile both in vitro in rat vascular smooth muscle cells and in vivo in Sprague Dawley rats after tail vein injection. In the rat model, the PTX-NaHCO3-PLGA NPs treatment group showed suppressed intimal proliferation following balloon-induced carotid artery injury compared with that of the saline-treated control. Overall, these results demonstrate that our newly developed pH-responsive nanodrug delivery platform has the potential to effectively inhibit restenosis.

Multifunctional and thermoresponsive methylcellulose composite hydrogels with photothermal effect

Multifunctional and thermoresponsive hydrogels can be used as soft materials in various medical applications, such as beauty devices, drug delivery, and near-infrared (NIR) lasers. In this study, methylcellulose (MC) composite hydrogels containing tannic acid (TA) and Fe³⁺ were prepared via a simple, fast process. The MC composite hydrogel contains hydrogen bonds between the MC polymer and TA and coordination bonds between TA and Fe³⁺, without losing the reversible thermogelation properties of the MC polymer. The gelation rates and mechanical properties of the MC composite hydrogel were controlled by varying its TA and Fe³⁺ contents. In particular, the hydrogel with a TA-Fe chelating complex showed an excellent photothermal effect, indicating its potential application in cosmetic beauty devices. It also exhibited UV-blocking, antioxidant, and antibacterial properties owing to the multifunctional TA. The facile processing of these MC/TA/Fe hydrogels provides new opportunities for biomedical applications and beauty devices employing NIR laser therapy.

In vivo spectroscopic photoacoustic imaging and laser-induced nanoparticle vaporization for anti-HER2 breast cancer

This study reports on the development and application of theragnostic agents targeting the HER2 receptors in breast tumors. The agent was constructed by loading silica-coated gold nanorods (GNRs) and a perfluorohexane liquid into PLGA-PEG nanoparticles, followed by surface conjugation with antibody Herceptin. The particle uptake in human breast cancer MDA-MB-231 (HER2-negative) and BT474 (HER2-positive) cell lines was tested. A proof of principle in vivo study was also performed using a xenograft mouse bilateral tumor model (16 mice, 32 tumors). Photoacoustic imaging was performed using a VevoLAZR device at 720/750/850 nm illuminations and 21 MHz central frequency. The relative concentrations of GNRs in the tumor were quantified using a linear spectral unmixing technique. The therapeutic efficacy of these nanoparticles was evaluated through optical droplet vaporization, and cell damage was confirmed using tissue immunofluorescence and histology. Our results demonstrate the potential of PLGA-GNRs as theragnostic agents for anti-HER2 breast cancer therapy.

iRGD Peptide-Mediated Liposomal Nanoparticles with Photoacoustic/Ultrasound Dual-Modality Imaging for Precision Theranostics Against Hepatocellular Carcinoma

Purpose

Prepare a multifunctional ultrasound molecular probe, cell-penetrating peptide-modified 10-hydroxycamptothecin-loaded phase-transformation lipid nanoparticles (iRGD-ICG-10-HCPT-PFP-NPs), and to combine iRGD-ICG-10-HCPT-PFP -NPs with low-intensity focused ultrasound (LIFU) for precision theranostics against hepatocellular carcinoma (HCC).

Materials and Methods

The morphology of nanoparticles (NPs) and iRGD-ICG-10-HCPT-PFP-NPs was detected. In vitro, we examined targeting ability by flow cytometry and confocal laser scanning microscopy (CLSM), assessed penetration ability into hepatoma cells, and assessed killing ability. In vivo, we examined the targeting ability of the NPs with a photoacoustic (PA) imager and fluorometer (FL), while LIFU irradiation was used to trigger the release of chemotherapeutic drugs, which had a therapeutic effect on tumors.

Results

The particle size of iRGD-ICG-10-HCPT-PFP-NPs was 298.4 ± 10.42 nm. In vitro, iRGD-ICG-10-HCPT-PFP-NPs bound more to SK-Hep1 cells than ICG-10-HCPT-PFP-NPs. iRGD-ICG-10-HCPT-PFP-NPs could achieve PA/ultrasound imaging. The percentage of antiproliferative and apoptotic cells in the iRGD-ICG-10-HCPT-PFP-NPs+LIFU group was significantly higher. In vivo, iRGD-ICG-10-HCPT-PFP-NPs can target tumor sites and achieve PA/ultrasound imaging. The tumor volume in the iRGD-ICG-10-HCPT-PFP-NPs+LIFU group was significantly smaller, and the antiproliferative and proapoptotic effects were higher.

Conclusion

We successfully prepared a novel molecular probe that has good targeting, can perform ultrasound/PA dual-modality imaging, and can penetrate deep into tumors to achieve better therapeutic tumor effects, providing a new idea and method for theranostics of HCC.

Tumor-self-targeted "thermoferroptosis-sensitization" magnetic nanodroplets for multimodal imaging-guided tumor-specific therapy

Ferroptosis-based nanomedicine has drawn increasing attention in antitumor therapy because of the advantages of this unconventional mode of apoptosis, but the difficulties of delivery to the tumor site and surface-to-core penetration after arrival seriously hinder further clinical transformation and application. Herein, we propose an unprecedented strategy of injecting magnetic nanodroplets (MNDs) to solve these two longstanding problems. MNDs are nanocarriers that can carry multifunctional drugs and imaging materials. MNDs can effectively accumulate in the tumor site by active tumor targeting (multifunctional drugs) and passive tumor targeting (enhanced permeability and retention effect), allowing diffusion of the MNDs from the surface to the core through mild-temperature magnetic fluid hyperthermia (MHT) under multimodal imaging guidance. Finally, the ferroptosis pathway is activated deep within the tumor site through the drug release. This approach was inspired by the ability of mild-temperature MHT to allow MNDs to quickly pass through the blood vessel-tumor barrier and deeply penetrate the tumor tissue from the surface to the core to amplify the antitumor efficacy of ferroptosis. This strategy is termed as "thermoferroptosis sensitization". Importantly, this behavior can be performed under the guidance of multimodal imaging, making the design of MNDs for cancer therapy safer and more reasonable.

Bioinspired Camellia japonica carbon dots with high near-infrared absorbance for efficient photothermal cancer therapy

Since carbon dots (CDs) exhibit excellent biocompatibility, low cytotoxicity, near-infrared (NIR) absorbance, and superior photostability, many types of CDs are considered as powerful candidates for photothermal therapy (PTT) applications. However, the development of a desirable CD is still difficult due to insufficient photothermal conversion, thus resulting in the use of high laser power densities at a high dose of CDs for the PTT effect. Herein, bioinspired sulfur-doped CDs (S-CDs) with strong NIR absorbance were prepared from Camellia japonica flowers via a facile hydrothermal method for enhancing the photothermal conversion efficiency. The as-prepared S-CDs exhibited various advantages including cost-effective preparation, good water-solubility, high biocompatibility, intense NIR absorption, and excellent photothermal effect with robust photostability. Most importantly, the optimal low dose of S-CDs (45 μg mL^-1) successfully led to efficient PTT performance with a high photothermal conversion efficiency (55.4%) under moderate laser power (808 nm, 1.1 W cm^-2) for safe and effective cancer therapy.

Dual-sonosensitizer loaded phase-transition nanoparticles with tumor-targeting for synergistically enhanced sonodynamic therapy

Sonodynamic therapy (SDT) is a fast-growing therapy activated by using ultrasound to initiate a catalytic reaction of sensitizing agents and kill tumor cells through producing reactive oxygen species (ROS). Both sinoporphyrin sodium (DVDMS) and IR780 are preeminent sonosensitizers and have been used in SDT alone. In this study, tumor targeting multifunctional composite nanoparticles (DVDMS@IR780@PFP@PLGA, DIPP-NPs) were synthesized by encapsulating DVDMS, IR780 and perfluoropentane (PFP) to synergistically enhance SDT and achieve imaging of tumors. The loaded IR780 is regarded as a "navigator" to accurately identify and target tumor cells/tissues. DVDMS and IR780 not only can realize the directed SDT, but also can perform photoacoustic (PA) imaging. PFP plays its role in enhancing the ultrasound (US) imaging. Generally, DIPP-NPs not only have an obvious synergistic anti-tumor effect, but also are able to carry out dual-mode imaging, which paves a promising way for tumor therapy.

Palladium nanoplates scotch breast cancer lung metastasis by constraining epithelial-mesenchymal transition

Metastasis accounts for the majority of cancer deaths in many tumor types including breast cancer. Epithelial-mesenchymal transition (EMT) is the driving force for the occurrence and progression of metastasis, however, no targeted strategies to block the EMT program are currently available to combat metastasis. Diverse engineered nanomaterials (ENMs) have been reported to exert promising anti-cancer effects, however, no ENMs have been designed to target EMT. Palladium (Pd) nanomaterials, a type of ENM, have received substantial attention in nanomedicine due to their favorable photothermal performance for cancer therapeutics. Herein, Pd nanoplates (PdPL) were found to be preferentially biodistributed to both primary tumors and metastatic tumors. Importantly, PdPL showed a significant inhibition of lung metastasis with and without near-infrared (NIR) irradiation. Mechanistic investigations revealed that EMT was significantly compromised in breast cancer cells upon the PdPL treatment, which was partially due to the inhibition of the transforming growth factor-beta (TGF-β) signaling. Strikingly, the PdPL was found to directly interact with TGF-β proteins to diminish TGF-β functions in activating its downstream signaling, as evidenced by the reduced phosphorylation of Smad2. Notably, TGF-β-independent pathways were also involved in undermining EMT and other important biological processes that are necessary for metastasis. Additionally, NIR irradiation elicited synergistic effects on PdPL-induced inhibition of primary tumors and metastasis. In summary, these results revealed that the PdPL remarkably curbed metastasis by inhibiting EMT signaling, thereby indicating the promising potential of PdPL as a therapeutic agent for treating breast cancer metastasis.

NIR Laser Responsive Nanoparticles for Ovarian Cancer Targeted Combination Therapy with Dual-Modal Imaging Guidance

Purpose

Multifunctional nanoparticles with targeted therapeutic function and diagnostic-imaging are of great interest in the domain of precision therapy. NIR laser responsive nanoparticles (PLGA-PEG-FA encapsulating Bi₂S₃, PFP, and Dox (designed as FBPD NPs)) are synthesized for ovarian cancer targeted combination therapy with CT/PA dual-modal imaging guidance (PA: photoacoustic; CT: X-ray computed tomography).

Methods and Results

The FBPD NPS prepared by the double emulsification method revealed excellent dispersity, great stability, outstanding optical properties. The temperature of FBPD NPs increased rapidly after laser irradiation, inducing liquid-to-gas conversion of perfluoropentane (PFP), and promoting the release of Dox up to 86.7%. These FBPD NPs demonstrated their outstanding imaging capability for both PA and CT imaging both in vitro and in vivo, providing the potential for therapeutic guidance and monitoring. Assisted by folic acid, these nanoparticles could highly enrich in ovarian tumor tissue and the accumulation peaked at 3 h after intravenous administration. The desirable photothermal-conversion efficiency of the nanoparticles combined with chemotherapy achieved highly efficient therapy, which was demonstrated both in vitro and in vivo.

Conclusion

We successfully constructed multifunctional theranostic FBPD NPs for highly efficient PTT/chemotherapy combined therapy with dual CT/PA imaging guidance/monitoring. The unique nanoparticles with multiple abilities pave an emerging way toward precise treatment of ovarian cancer.

Anti-HER2 PLGA-PEG polymer nanoparticle containing gold nanorods and paclitaxel for laser-activated breast cancer detection and therapy

Phase-transition nanoparticles have been identified as effective theragnostic, anti-cancer agents. However, non-selective delivery of these agents results in inaccurate diagnosis and insufficient treatment. In this study, we report on the development of targeted phase-transition polymeric nanoparticles (NPs) for the imaging and treatment of breast cancer cell lines over-expressing human epidermal growth factor receptor 2 (HER2). These NPs contain a perfluorohexane liquid interior and gold nanorods (GNRs) stabilized by biodegradable and biocompatible copolymer PLGA-PEG. Water-insoluble therapeutic drug Paclitaxel (PAC) and fluorescent dye were encapsulated into the PLGA shell. The NP surfaces were conjugated to HER2-binding agent, Herceptin, to actively target HER2-positive cancer cells. We evaluated the potential of using these NPs as a photoacoustic contrast agent. The efficacy of cancer cell treatment by laser-induced vaporization and stimulated drug release were also investigated. The results showed that our synthesized PLGA-PEG-GNRs (mean diameter 285 ± 29 nm) actively targeted HER2 positive cells with high efficacy. The laser-induced vaporization caused more damage to the targeted cells versus PAC-only and negative controls. This agent may provide better diagnostic imaging and therapeutic potential than current methods for treating HER2-positive breast cancer.

A non-invasive nanoparticles for multimodal imaging of ischemic myocardium in rats

BACKGROUND

Ischemic heart disease (IHD) is the leading cause of morbidity and mortality worldwide, and imposes a serious economic load. Thus, it is crucial to perform a timely and accurate diagnosis and monitoring in the early stage of myocardial ischemia. Currently, nanoparticles (NPs) have emerged as promising tools for multimodal imaging, because of their advantages of non-invasion, high-safety, and real-time dynamic imaging, providing valuable information for the diagnosis of heart diseases.

RESULTS

In this study, we prepared a targeted nanoprobe (termed IMTP-Fe3O4-PFH NPs) with enhanced ultrasound (US), photoacoustic (PA), and magnetic resonance (MR) performance for direct and non-invasive visual imaging of ischemic myocardium in a rat model. This successfully designed nanoprobe had excellent properties such as nanoscale size, good stability, phase transformation by acoustic droplet vaporization (ADV), and favorable safety profile. Besides, it realized obvious targeting performance toward hypoxia-injured cells as well as model rat hearts. After injection of NPs through the tail vein of model rats, in vivo imaging results showed a significantly enhanced US/PA/MR signal, well indicating the remarkable feasibility of nanoprobe to distinguish the ischemic myocardium.

CONCLUSIONS

IMTP-Fe3O4-PFH NPs may be a promising nanoplatform for early detection of ischemic myocardium and targeted treatment under visualization for the future.

Integration of Multitargeted Polymer-Based Contrast Agents with Photoacoustic Computed Tomography: An Imaging Technique to Visualize Breast Cancer Intratumor Heterogeneity

One of the primary challenges in breast cancer diagnosis and treatment is intratumor heterogeneity (ITH), i.e., the coexistence of different genetically and epigenetically distinct malignant cells within the same tumor. Thus, the identification of ITH is critical for designing better treatments and hence to increase patient survival rates. Herein, we report a noninvasive hybrid imaging technology that integrates multitargeted and multiplexed patchy polymeric photoacoustic contrast agents (MTMPPPCAs) with single-impulse panoramic photoacoustic computed tomography (SIP-PACT). The target specificity ability of MTMPPPCAs to distinguish estrogen and progesterone receptor-positive breast tumors was demonstrated through both fluorescence and photoacoustic measurements and validated by tissue pathology analysis. This work provides the proof-of-concept of the MTMPPPCAs/SIP-PACT system to identify ITH in nonmetastatic tumors, with both high molecular specificity and real-time detection capability.

Tuning the Interfacial Properties of Fluorous Colloids Toward Ultrasound Programmable Bioactivity

Liquid-in-liquid emulsions are kinetically stable colloids that undergo liquid-to-gas phase transitions in response to thermal or acoustic stimuli. Perfluorocarbons (PFCs) are preferred species as their highly fluorinated nature imparts unique properties that are unparalleled by nonfluorinated counterparts. However, traditional methods to prepare PFC emulsions lack the ability to precisely tune the thermodynamic stability of the fluorous-water interphase and consequently control their vaporization behavior. Here, we report a privileged fluoroalkanoic acid that undergoes concentration-dependent assembly on the surfaces of fluorous droplets to modulate interfacial tension. This allows for the rational formulation of orthogonal PFC droplets that can be programmed to vaporize at specified ultrasound powers. We exploit this behavior in two exemplary biomedical settings by developing emulsions that aid ultrasound-mediated hemostasis and enable bioorthogonal delivery of molecular sensors to mammalian cells. Mechanistic insights gained from these studies can be generalized to tune the thermodynamic interfacial equilibria of PFC emulsions toward designing controllable tools for precision medicine.

Plasmonic carriers responsive to pulsed laser irradiation: a review of mechanisms, design, and applications

This review focuses on interactions which govern release from plasmonic carrier systems including liposomes, polymersomes, and nanodroplets under pulsed irradiation.

MRI-traceable theranostic nanoparticles for targeted cancer treatment

Current cancer therapies, including chemotherapy and radiotherapy, are imprecise, non-specific, and are often administered at high dosages - resulting in side effects that severely impact the patient's overall well-being. A variety of multifunctional, cancer-targeted nanotheranostic systems that integrate therapy, imaging, and tumor targeting functionalities in a single platform have been developed to overcome the shortcomings of traditional drugs. Among the imaging modalities used, magnetic resonance imaging (MRI) provides high resolution imaging of structures deep within the body and, in combination with other imaging modalities, provides complementary diagnostic information for more accurate identification of tumor characteristics and precise guidance of anti-cancer therapy. This review article presents a comprehensive assessment of nanotheranostic systems that combine MRI-based imaging (T1 MRI, T2 MRI, and multimodal imaging) with therapy (chemo-, thermal-, gene- and combination therapy), connecting a range of topics including hybrid treatment options (e.g. combined chemo-gene therapy), unique MRI-based imaging (e.g. combined T1-T2 imaging, triple and quadruple multimodal imaging), novel targeting strategies (e.g. dual magnetic-active targeting and nanoparticles carrying multiple ligands), and tumor microenvironment-responsive drug release (e.g. redox and pH-responsive nanomaterials). With a special focus on systems that have been tested in vivo, this review is an essential summary of the most advanced developments in this rapidly evolving field.

Visualized podocyte-targeting and focused ultrasound responsive glucocorticoid nano-delivery system against immune-associated nephropathy without glucocorticoid side effect

Glucocorticoids are widely used in the treatment of nephritis, however, its dose-dependent side effects, such as the increased risk of infection and metabolic disturbances, hamper its clinical use. This study reports a visualized podocyte-targeting and focused ultrasound responsive glucocorticoid nano-delivery system (named as Dex/PFP@LIPs-BMS-α), which specific delivers dexamethasone (Dex) to podocyte targets and reduces systemic side effects.

Methods: The glucocorticoid nano-delivery system was synthesized by a lipid thin film and a simple facile acoustic-emulsification method. This glucocorticoid nano-delivery system used BMS-470539 (BMS-α), a synthetic compound, as a “navigator” to specifically identify and target the melanocortin-1 receptor (MC-1R) on podocytes. The loaded perfluoropentane (PFP) realizes the directed "explosion effect" through ultrasound-targeted microbubble destruction (UTMD) technology under the coordination of low intensity focused ultrasound (LIFU) to completely release Dex.

Results: Both in vitro and in vivo experiments have demonstrated that Dex/PFP@LIPs-BMs-α accurately gathered to podocyte targets and improved podocyte morphology. Moreover, in vivo, proteinuria and serum creatinine levels were significantly reduced in the group treated with Dex/PFP@LIPs-BMS-α, and no severe side effects were detected. Furthermore, Dex/PFP@LIPs-BMS-α, with capabilities of ultrasound, photoacoustic and fluorescence imaging, provided individualized visual guidance and the monitoring of treatment.

Conclusion: This study provides a promising strategy of Dex/PFP@LIPs-BMS-α as effective and safe against immune-associated nephropathy.

Photoimmunotherapy with cetuximab-conjugated gold nanorods reduces drug resistance in triple negative breast cancer spheroids with enhanced infiltration of tumor-associated macrophages

Tumor-associated macrophages (TAM) constitute up to 50-80% of stromal cells in breast cancer (BC), and are correlated with poor prognosis. As epidermal growth factor receptor (EGFR) is overexpressed in 60-80% of patients with triple negative breast cancer (TNBC), photoimmunotherapy (PIT) with cetuximab-targeted gold nanorods (CTX-AuNR) is an attractive therapeutic strategy for TNBC. The 3D cell culture model can mimic drug resistance conferred by the tumor microenvironment and its 3D organization; therefore, TAM and non-TAM embedded TNBC spheroids were constructed to evaluate the therapeutic efficacy of CTX-AuNR plus near infrared (NIR) irradiation. Cytotoxicity, reactive oxygen species (ROS) generation, and protein expression were compared in TNBC (± TAM) spheroids. The IC₅₀ values of doxorubicin (DOX) in TAM-embedded TNBC spheroids were significantly higher than those in TNBC spheroids, demonstrating drug resistance, which could be explained by activation of IL-10/IL-10 receptor/STAT3/Bcl-2 signaling. However, 3D in vitro and in vivo results demonstrated that the efficacy of CTX-AuNR plus NIR irradiation was not significantly different in (± TAM) embedded TNBC cells. By enhancing ROS generation, CTX-AuNR plus NIR irradiation reprogrammed TAM polarization to the M1 anti-tumor phenotype, as indicated by macrophage mannose receptor (MMR) downregulation. Thus, CTX-AuNR plus NIR can serve as a potent PIT strategy for treating EGFR-overexpressing TNBC cells.

A mitochondria-targeted anticancer nanoplatform with deep penetration for enhanced synergistic sonodynamic and starvation therapy

Sonodynamic therapy (SDT), as an emerging technique, gives rise to reactive oxygen species (ROS)-induced apoptosis of tumor cells. However, nonselective enrichment and unsatisfactory penetration depth of sonosensitizers in tumor tissues limit its application. In this study, we synthesized core/shell (glucose oxidase (GOx) in the core/hematoporphyrin monomethyl ether (HMME) and IR780 in the shell) structured polylactic-co-glycolic acid (PLGA) nanoparticles (NPs) with deep tumor penetration and mitochondrial targeting capability for synergistic sonodynamic and starvation therapy. After passing through the endothelial space of tumor vasculatures, by virtue of IR780, these NPs can selectively accumulate towards cancer cells/sites, especially in mitochondria and diffuse into deep tumour centres. Upon ultrasound (US) exposure, the overproduced ROS cause tumor cell apoptosis. Sonodynamic effects can be amplified by mitochondrial targeting because mitochondria are susceptible to ROS. GOx blocks glucose (energy) supply, further suppressing the growth of malignant tumors. This synergistic therapy exhibited a superb response to treatment (4.7-fold lower tumor growth in volume than the control group). In addition, these NPs also serve as excellent photoacoustic (PA)/fluorescent (FL) imaging contrast agents to simultaneously monitor and guide cancer therapy. This study paves a promising way to achieve an ideal strategy for cancer therapy.

Enzyme-instructed self-aggregation of Fe3O4 nanoparticles for enhanced MRI T2 imaging and photothermal therapy of tumors

The aggregation of superparamagnetic iron oxide (SPIO) nanoparticles (NPs) can greatly enhance magnetic resonance imaging (MRI) T2-weighted imaging and near-infrared (NIR) absorption in experiments. In this study, an Ac-Arg-Val-Arg-Arg-Cys(StBu)-Lys-CBT probe was designed and coupled with monodispersed carboxyl-decorated SPIO NPs to form SPIO@1NPs, which use it for intracellular self-aggregation. In vitro experiments showed that the self-aggregation of SPIO@1NPs was induced by a condensation reaction mediated by the enzyme furin in furin-overexpressing tumor cells. Moreover, the NPs in the aggregated state showed significantly higher MR r2 values and photothermal conversion efficiency than the NPs in the monodisperse state. Then, the in vivo SPIO@1NP self-aggregation in tumors can facilitate accurate MRI T2 imaging-guided photothermal therapy for effectively killing cancer cells. We believe that this basic technique, based on tumor-specific enzyme-instructed intracellular self-aggregation of NPs, could be useful for the rational synthesis of other inorganic NPs for use in the fields of tumor diagnosis and treatment.

A sequential targeting nanoplatform for anaplastic thyroid carcinoma theranostics

Effective accumulation of nanoparticles (NPs) in tumor regions is one of the major motivations in nanotechnology research and that the establishment of an efficient targeting nanoplatform for the treatment of malignant tumors is urgently needed for theranostic applications. In this study, we engineered multifunctional sequential targeting NPs for achieving synergistic antiangiogenic photothermal therapy (PTT) and multimodal imaging-guided diagnosis for anaplastic thyroid carcinoma (ATC) theranostics. Antibody bevacizumab with an affinity towards vascular endothelial growth factor (VEGF) on the tumor cell surface was conjugated onto the surface of polymer NPs for VEGF targeting and antiangiogenic therapy. Encapsulated IR825 was employed as a photothermal agent (PTA) with a mitochondrial targeting capability, which further cascades NPs into mitochondria to enhance hyperthermic efficiency in the ablation of tumor cells. Importantly, the combination of bevacizumab and IR825 in a single nanosystem achieved desirable accumulations of NPs and that sequential targeted PTT combined with antiangiogenesis significantly promoted the therapeutic efficiency in eradicating tumors by near-infrared (NIR) laser irradiation. Furthermore, these NPs are extraordinary contrast agents for photoacoustic, ultrasound and fluorescence imaging applications, providing multimodal imaging capabilities for therapeutic monitoring and a precise diagnosis. Therefore, this multifunctional nanoplatform provides a promising theranostic strategy for extremely malignant ATC. STATEMENT OF SIGNIFICANCE: Anaplastic thyroid carcinoma (ATC), with extremely aggressive behavior, lacks a satisfactory therapeutic method and a comprehensive early diagnostic strategy. Herein, we successfully synthesized a sequential targeting nanoplatform (IR825@Bev-PLGA-PFP NPs) with theranostic function, which specifically binds to VEGF on the tumor cell surface and further cascades into mitochondria to achieve effective accumulation of NPs in the tumor regions. As a result, it solves the urgent demand for ATC detection and therapy. By breaking the limitation of traditional target, such as low efficacy and frequent recurrence as the results of low accumulation, sequential targeting combined with synergistic antiangiogenic PTT completely eradicates tumors without any residual tissue and side effect. Therefore, this strategy paves a solid way for further investigation in the theranostic progressing of ATC.

Coordination-induced exfoliation to monolayer Bi-anchored MnB2 nanosheets for multimodal imaging-guided photothermal therapy of cancer

Background: Rapid advance in biomedicine has recently vitalized the development of multifunctional two-dimensional (2D) nanomaterials for cancer theranostics. However, it is still challenging to develop new strategy to produce new types of 2D nanomaterials with flexible structure and function for enhanced disease theranostics. Method: We explore the monolayer Bi-anchored manganese boride nanosheets (MBBN) as a new type of MBene (metal boride), and discover their unique near infrared (NIR)-photothermal and photoacoustic effects, X-ray absorption and MRI imaging properties, and develop them as a new nanotheranostic agent for multimodal imaging-guided photothermal therapy of cancer. A microwave-assisted chemical etching route was utilized to exfoliate the manganese boride bulk into the nanosheets-constructed flower-like manganese boride nanoparticle (MBN), and a coordination-induced exfoliation strategy was further developed to separate the MBN into the dispersive monolayer MBBN by the coordination between Bi and B on the surface, and the B-OH group on the surface of MBBN enabled facile surface modification with hyaluronic acid (HA) by the borate esterification reaction in favor of enhanced monodispersion and active tumor targeting. Result: The constructed MBBN displays superior NIR-photothermal conversion efficiency (η=59.4%) as well as high photothermal stability, and possesses versatile imaging functionality including photoacoustic, photothermal, CT and T1 -wighted MRI imagings. In vitro and in vivo evaluations indicate that MBBN had high photothermal ablation and multimodal imaging performances, realizing high efficacy of imaging-guided cancer therapy. Conclusion: We have proposed new MBene concept and exfloliation strategy to impart the integration of structural modification and functional enhancement for cancer theranostics, which would open an avenue to facile fabrication and extended application of multifunctional 2D nanomaterials.

The Destruction Of Laser-Induced Phase-Transition Nanoparticles Triggered By Low-Intensity Ultrasound: An Innovative Modality To Enhance The Immunological Treatment Of Ovarian Cancer Cells

Purpose

Photodynamic therapy (PDT), sonodynamic therapy (SDT), and oxaliplatin (OXP) can induce immunogenic cell death (ICD) following damage-associated molecular patterns (DAMPs) exposure or release and can be united via the use of nanoplatforms to deliver drugs that can impart anti-tumor effects. The aim of this study was to develop phase-transition nanoparticles (OI_NPs) loaded with perfluoropentane (PFP), indocyanine green (ICG), and oxaliplatin (OXP), to augment anti-tumor efficacy and the immunological effects of chemotherapy, photodynamic therapy and sonodynamic therapy (PSDT).

Methods

OI_NPs were fabricated by a double emulsion method and a range of physicochemical and dual-modal imaging features were characterized. Confocal microscopy and flow cytometry were used to determine the cellular uptake of OI_NPs by ID8 cells. The viability and apoptotic rate of ID8 cells were investigated using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay and flow cytometry. Flow cytometry, Western blotting, and luminometric assays were then used to investigate the exposure or release of crucial DAMPs such as calreticulin (CRT), high mobility group box 1 (HMGB1), and adenosine-5ʹ-triphosphate (ATP). Tumor rechallenge experiments were then used to investigate whether treated ID8 cells underwent ICD. Finally, cytotoxic T lymphocyte (CTL) activity was determined by a lactate dehydrogenase (LDH) assay.

Results

Spherical OI_NPs were able to carry OXP, ICG and PFP and were successfully internalized by ID8 cells. The application of OI_NPs significantly enhanced the phase shift ability of PFP and the optical characteristics of ICG, thus leading to a significant improvement in photoacoustic and ultrasonic imaging. When combined with near-infrared light and ultrasound, the application of OI_NPs led to improved anti-tumor effects on cancer cells, and significantly enhanced the expression of DAMPs, thus generating a long-term anti-tumor effect.

Conclusion

The application of OI_NPs, loaded with appropriate cargo, may represent a novel strategy with which to increase anti-tumor effects, enhance immunological potency, and improve dual-mode imaging.

Combination of light-driven co-delivery of chemodrugs and plasmonic-induced heat for cancer therapeutics using hybrid protein nanocapsules

BACKGROUND

Improving the water solubility of hydrophobic drugs, increasing their accumulation in tumor tissue and allowing their simultaneous action by different pathways are essential issues for a successful chemotherapeutic activity in cancer treatment. Considering potential clinical application in the future, it will be promising to achieve such purposes by developing new biocompatible hybrid nanocarriers with multimodal therapeutic activity.

RESULTS

We designed and characterised a hybrid nanocarrier based on human serum albumin/chitosan nanoparticles (HSA/chitosan NPs) able to encapsulate free docetaxel (DTX) and doxorubicin-modified gold nanorods (DOXO-GNRs) to simultaneously exploit the complementary chemotherapeutic activities of both antineoplasic compounds together with the plasmonic optical properties of the embedded GNRs for plasmonic-based photothermal therapy (PPTT). DOXO was assembled onto GNR surfaces following a layer-by-layer (LbL) coating strategy, which allowed to partially control its release quasi-independently release regarding DTX under the use of near infrared (NIR)-light laser stimulation of GNRs. In vitro cytotoxicity experiments using triple negative breast MDA-MB-231 cancer cells showed that the developed dual drug encapsulation approach produces a strong synergistic toxic effect to tumoral cells compared to the administration of the combined free drugs; additionally, PPTT enhances the cytostatic efficacy allowing cell toxicities close to 90% after a single low irradiation dose and keeping apoptosis as the main cell death mechanism.

CONCLUSIONS

This work demonstrates that by means of a rational design, a single hybrid nanoconstruct can simultaneously supply complementary therapeutic strategies to treat tumors and, in particular, metastatic breast cancers with good results making use of its stimuli-responsiveness as well as its inherent physico-chemical properties.

Folate-Targeted and Oxygen/Indocyanine Green-Loaded Lipid Nanoparticles for Dual-Mode Imaging and Photo-sonodynamic/Photothermal Therapy of Ovarian Cancer in Vitro and in Vivo

We have successfully fabricated versatile folate-targeted and oxygen/indocyanine green-loaded lipid nanoparticles (FA-OINPs) for dual-mode imaging-guided therapy in ovarian cancer cells and subcutaneous xenograft models. FA-OINPs were demonstrated to have great potential as superb contrast agents to enhance ultrasound and photoacoustic (US/PA) imaging We have successfully fabricated versatile folate-targeted and oxygen/indocyanine green-loaded lipid nanoparticles (FA-OINPs) for dual-mode imaging-guided therapy in ovarian cancer cells and subcutaneous xenograft models. FA-OINPs were demonstrated to have great potential as superb contrast agents to enhance ultrasound and photoacoustic (US/PA) imaging in vitro and in vivo. Confocal laser scanning microscopy and flow cytometry analysis verified that FA-OINPs could specifically target SKOV3 ovarian cancer cells and be endocytosed with a remarkable efficiency. Compared with other therapeutic options, FA-OINPs exhibited an excellent therapeutic outcome after exposure to laser and ultrasound. The MTT assay and flow cytometry analysis confirmed that cytotoxicity effects and apoptosis/necrosis rates were significantly increased. The fluorescence microscopy and fluorescence microplate reader detection validated that the generation of intracellular reactive oxygen species (ROS) was dramatically improved. Immunohistochemical analyses of tumor tissues demonstrated the enhanced tumor apoptosis, the decreased vascular endothelial growth factor (VEGF) and microvascular density (MVD) expression, and the decreased expression of CD68 after treatment. The presented results suggest that photo-sonodynamic/photothermal mediated FA-OINPs could provide a promising strategy for synergistic therapy in ovarian cancer with the guidance of US/PA dual-mode imaging.

A new strategy for accurate targeted diagnosis and treatment of cutaneous malignant melanoma: dual-mode phase-change lipid nanodroplets as ultrasound contrast agents

Background

Currently, effective detection and treatment of cutaneous malignant melanoma (CMM) still face severe challenges. Ultrasound molecular imaging as a noninvasive and easy-to-operate method is expected to bring improvements for tumor detection.

Purpose

The aim of this research is to prepare novel phase-change ultrasound contrast agents, Nds-IR780, which can perform not only dual-mode molecule-targeted imaging but also targeted photothermal therapy for CMM.

Methods

A double emulsion process was used to prepare the Nds-IR780. Then, the entrapment rate and drug loading of IR-780 iodide in Nds-IR780 were detected by high-performance liquid chromatography. The biocompatibility of Nds-IR780 was evaluated by a CCK-8 assay and the characteristics and stability of that were verified through the particle size analyzer, laser scanning confocal microscopy (LSCM) and transmission electron microscopy (TEM). The abilities of dual-mode molecule-targeted imaging and targeted photothermal therapy for Nds-IR780 were confirmed via the in vitro and in vivo experiments.

Results

Nds-IR780 had good size distribution, polydispersity index, stability and biosafety. The in vitro and in vivo experiments confirmed that Nds-IR780 were capable of targeting CMM cells with high affinity (22.4±3.2%) and facilitating dual-mode imaging to detect the primary lesion and sentinel lymph nodes (SLNs) of CMM. Furthermore, the photothermal ablation of CMM mediated by Nds-IR780 was very effective in vivo.

Conclusion

The newly prepared Nds-IR780 were observed to be effective targeted theranostic probe for the precise detection and targeted treatment of CMM.

Near-Infrared Fluorescent Sorbitol Probe for Targeted Photothermal Cancer Therapy

Abstract: Photothermal therapy (PTT) using a near-infrared (NIR) heptamethine cyanine fluorophore has emerged as an alternative strategy for targeted cancer therapy. NIR fluorophores showing a high molar extinction coefficient and low fluorescence quantum yield have considerable potential applications in photothermal cancer therapy. In this study, a bifunctional sorbitol-ZW800 conjugate was used as an advanced concept of photothermal therapeutic agents for in vivo cancer imaging and therapy owing to the high tumor targetability of the sorbitol moiety and excellent photothermal property of NIR heptamethine cyanine fluorophore. The sorbitol-ZW800 showed an excellent photothermal effect increased by 58.7 °C after NIR laser irradiation (1.1 W/cm2) for 5 min. The HT-29 tumors targeted by sorbitol-ZW800 showed a significant decrease in tumor volumes for 7 days after photothermal treatment. Therefore, combining the bifunctional sorbitol-ZW800 conjugate and NIR laser irradiation is an alternative way for targeted cancer therapy, and this approach holds great promise as a safe and highly efficient NIR photothermal agent for future clinical applications.

Bombesin-functionalized superparamagnetic iron oxide nanoparticles for dual-modality MR/NIRFI in mouse models of breast cancer

Background

The early and accurate detection afforded by imaging techniques significantly reduces mortality in cancer patients. However, it is still a great challenge to achieve satisfactory performance in tumor diagnosis using any single-modality imaging method. Magnetic resonance imaging (MRI) has excellent soft tissue contrast and high spatial resolution, but it suffers from low sensitivity. Fluorescence imaging has high sensitivity, but it is limited by penetration depth. Thus, the combination of the two modes could result in synergistic benefits. Here, we design and characterize a novel dual-modality MR/near-infrared fluorescence imaging (MR/NIRFI) nanomicelle and test its imaging properties in mouse models of breast cancer.

Methods

The nanomicelles were prepared by incorporating superparamagnetic iron oxide (SPIO) nanoparticles into 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethylene glycol)-5000] micelles to which an NIRF dye and a tumor-targeted peptide (N₃-Lys-bombesin, Bom) were conjugated. The nanomicelles were characterized for particle size, zeta potential and morphology. The transverse relaxivity, targeting specificity and imaging ability of the nanomicelles for MR/NIRFI were also examined.

Results

The fabricated nanomicelles displayed a well-defined spherical morphology with a mean diameter of 145±56 nm and a high transverse relaxivity (493.9 mM⁻¹·s⁻¹, 3.0T). In MRI, the T₂ signal reduction of tumors in the Bom-targeted group was 24.1±5.7% at 4 hrs postinjection, whereas only a 0.1±3.4% (P=0.003) decrease was observed in the nontargeted group. In NIRFI, the contrast increased gradually in the targeted group, and the tumor/muscle ratio increased from 3.7±0.3 at 1 hr to 4.7±0.1 at 2 hrs and to 6.4±0.2 at 4 hrs. No significant changes were observed in the nontargeted group at any time points.

Conclusion

Considering all our results, we conclude that these novel MR/NIRFI dual-modality nanomicelles could be promising contrast agents for cancer diagnosis.

Construction of CNA35 Collagen-Targeted Phase-Changeable Nanoagents for Low-Intensity Focused Ultrasound-Triggered Ultrasound Molecular Imaging of Myocardial Fibrosis in Rabbits

Myocardial fibrosis plays an important role in the development of heart failure and malignant arrhythmia, which potentially increases the incidence of sudden cardiac death. Therefore, early detection of myocardial fibrosis is of great significance for evaluating the prognosis of patients and formulating appropriate treatment strategies. Late gadolinium-enhanced magnetic resonance imaging is considered as the currently effective strategy for noninvasive detection of myocardial fibrosis, but it still suffers from some critical issues. In this work, multifunctional CNA35-labeled perfluoropentane nanoparticles (CNA35-PFP NPs) have been elaborately designed and constructed for molecular imaging of fibrotic myocardium based on ultrasound imaging. These as-constructed CNA35-PFP NPs are intravenously infused into rabbit circulation with an animal model of myocardial infarction. Especially, these targeted CNA35-PFP NPs with nanoscale size could efficiently pass through the endothelial cell gap and adhere to the surface of fibroblasts in the fibrotic myocardium. Importantly, followed by low-intensity focused ultrasound irradiation on the myocardium, these intriguing CNA35-PFP NPs could transform from liquid into gaseous microbubbles, which further significantly enhanced the ultrasound contrast in the fibrotic area, facilitating the detection by diagnostic ultrasound imaging. Therefore, this work provides a desirable noninvasive, economical, and real-time imaging technique for the assessment of cardiac fibrosis with diagnostic ultrasound based on the rational design of liquid-to-gas phase-changeable nanoplatforms.