All-in-One Heptamethine Cyanine Amphiphiles for Dual Imaging-Guided Chemo-Photodynamic-Photothermal Therapy of Breast Cancer

Dextran-based nanodrugs with mitochondrial targeting/glutathione depleting synergy for enhanced photodynamic therapy

The efficacy of photodynamic therapy (PDT) for malignant tumors is significantly impeded by the short diffusion distance of reactive oxygen species (ROS) and the ROS-consuming glutathione (GSH) overexpressed in tumor cells. Therefore, enhanced PDT can be achieved by the construction of biomacromolecule-based nanodrugs that can specifically target ROS-sensitive mitochondria and deplete intracellular GSH. Herein, we synthesized the dextran-based nano-assemblies by a Graft copolymerization Induced Self-Assembly (GISA) method, in which methyl acrylate and diallyl disulfide (DADS) were copolymerized from a mixed dextran/amino dextran backbone in an aqueous medium. Notably, the disulfide bond-containing DADS served as both GSH-depleting agent and GSH-responsive crosslinker. In order to develop a nanodrug with mitochondrial targeting/GSH depleting synergy, we further conjugated a mitochondria-targeting ligand onto the amino dextran corona, and developed a "loading-post-assembly" strategy to load a hydrophobic photosensitizer protoporphyrin IX or even multi-drugs into the hydrophobic core of the nano-assemblies. Cell and animal studies illustrated that the nanodrug could accumulate in the mitochondria of tumor cells to generate ROS in situ and thus eliminate tumors. Taken together, our work presents the dextran-based nanodrug as an efficient platform to achieve mitochondria-targeting PDT with an enhanced efficiency by simultaneously depleting intracellular GSH.

Fluorination of Aza-BODIPY for Cancer Cell Plasma Membrane-Targeted Imaging and Therapy

Photodynamic therapy (PDT) holds great potential in cancer treatment, leveraging photosensitizers (PSs) to deliver targeted therapy. Fluorination can optimize the physicochemical and biological properties of PSs for better PDT performance. Here, we report some high-performance multifunctional PSs specifically designed for cancer PDT by fluorinating aza-BODIPY with perfluoro-tert-butoxymethyl (PFBM) groups. Fluorination plays several roles, including enhancing selective cancer cell uptake, plasma membrane (PM) targeting, and inducing pyroptosis. It also enables fluorescence imaging (FLI) and fluorine-19 magnetic resonance imaging (19F MRI) as well as facilitates oxygen delivery and oxygen partial pressure (pO2) measurements. Comparative physicochemical and biological studies, along with molecular dynamics simulations, reveal that fluorinated PSs selectively eradicate cancer cells by oxidizing PM phospholipids with singlet oxygen (1O2) and inducing pyroptosis, which enables effectively suppressed tumor growth by self-oxygenated 19F MRI-FLI-guided PDT in mice. This study demonstrates a fluorination strategy for tailoring high-performance multifunctional cancer PM-targeting materials for cancer therapy and beyond.

Multifunctional "Add-On" Module Enabled NIR-II Imaging-Guided Synergistic Photothermal and Chemotherapy of Drug-Resistant Lung Cancer

Imaging-guided chemo-photothermal combination therapy (chemo-PTT) is recognized for its synergistic therapeutic effects, reduced side effects, and minimal drug resistance, while the development of such theranostics has been hampered by poor imaging and therapy performance and tedious formulation. Herein, we introduce an all-in-one "add-on" module (BBT-C6) for the convenient construction of doxorubicin (DOX)-loaded nanoparticles (DOX@BBT) and efficient second near-infrared (NIR-II) fluorescence imaging (FLI)-guided synergistic chemo-PTT of drug-resistant lung cancer. The delicate Janus amphiphilic structure of BBT-C6 enables multifunctionality, including NIR-II FLI, aggregation-induced emission (AIE) characteristics, moderate photothermal conversion efficiency (PCE), excellent photostability, and polyethylene glycolation (PEGylation), which could improve the NIR-II FLI and PTT performance, relieve the complexity in theranostics, and enable high reproducibility of the multifunctional theranostics. Confocal microscopy revealed that BBT@DOX efficiently delivers DOX into cells, resulting in an increased accumulation of DOX that exceeds the efflux capacity of DOX-resistant cells. Both in vitro and in vivo studies demonstrate that BBT-C6 enhances the effectiveness of BBT@DOX, achieving highly effective photothermal-chemo synergistic therapy against DOX-resistant lung cancer. Beyond developing a versatile "add-on" module for conveniently constructing multifunctional nanosystems, this study provides new insights into the design of advanced theranostics for precise biomedical applications.

NIR-II Fluorescent Nanotheranostics with a Switchable Irradiation Mode for Immunogenic Sonodynamic Therapy

Nanotheranostics, which integrate diagnostic and therapeutic functionalities, offer significant potential for tumor treatment. However, current nanotheranostic systems typically involve multiple molecules, each providing a singular diagnostic or therapeutic function, leading to challenges such as complex structural composition, poor targeting efficiency, lack of spatiotemporal control, and dependence on a single therapeutic modality. This study introduces NPRBOXA, a nanoparticle functionalized with surface-bound cRGD for targeted delivery to αvβ3/αvβ5 receptors on tumor cells, achieving theranostic integration by sequentially switching its irradiation modes. Under 808 nm laser irradiation, NPRBOXA emits NIR-II fluorescence, which aids in identifying the nanoparticle's location and fluorescence intensity, thereby determining the optimal treatment window. Following this, the irradiation mode switches to ultrasound irradiation at the optimal treatment window. Ultrasound irradiation induces NPRBOXA to generate reactive oxygen species, promoting the reduction of OXA-IV to OXA-II, which in turn triggers immunogenic cell death. This mechanism enables a combination of sonodynamic therapy, chemotherapy, and immunotherapy for tumor treatment. The versatile design of NPRBOXA holds promise for advancing precision oncology through enhanced therapeutic efficacy and real-time imaging guidance.

An ATP-responsive ZIF-based NIR fluorescence nanosystem for enhanced chemo-photodynamic therapy of tumors

The combination of chemotherapy and photodynamic therapy holds immense potential for achieving synergistic anti-tumor efficacy. However, challenges such as poor stability and premature drug release prior to reaching tumor sites impede the widespread application of this synergistic therapeutic approach. In this study, a novel ATP-responsive NIR fluorescence nanosystem (CDZ) for imaging-guided chemotherapy and PDT has been developed. This nanosystem, based on ZIF-90, encapsulates the chemotherapy drug doxorubicin (DOX) and the photosensitizer asymmetrical cyanine dye Cy through self-assembly. The obtained nanosystem CDZ could efficiently avoid premature drug leakage in the blood circulation due to its high stability in the physiological environment and accumulates at the tumor sites via the enhanced permeability and retention (EPR) effect. Upon uptake by tumor cells, the skeleton structure of CDZ is disrupted by overexpressed ATP levels, leading to the release of DOX, which inhibits cancer cell proliferation and induces cell death. Additionally, the released photosensitizer Cy emits strong NIR fluorescence signals, enabling real-time imaging of ATP levels in tumors. Moreover, under NIR light irradiation, this nanosystem generates high levels of ROS, achieving effective phototherapy even in deeper tumor regions. In tumor model mice, CDZ demonstrated a high rate of tumor inhibition without causing damage to major organs. This ZIF-based NIR fluorescence nanosystem, combining chemotherapy and photodynamic therapy, holds promise as a solution for treating and monitoring cancer without the associated risks of resistance and systemic toxicity.

Symmetrically Fluorinated D-π-A Structured Cyanine Dye for Highly Efficient NIR-II Imaging-Guided Cancer Phototheranostics

Near-infrared-II (NIR-II) fluorescence imaging-guided photothermal therapy (PTT) represents a cutting-edge approach for precise tumor diagnosis and treatment, providing real-time therapeutic efficacy evaluation. However, a significant challenge lies in the creation of phototheranostic agents that provide robust imaging and efficient photothermal conversion. To address this, a donor-π-acceptor (D-π-A) structure heptamethine cyanine derivative, IR1116, that confers a strong intramolecular charge transfer effect is developed. To enhance its applicability, IR1116 is formulated with DSPE-PEG to create a water-dispersible NIR-II phototheranostic nanoheater, NPIR1116. This nanoheater benefits from the incorporation of an electron-withdrawing group, leading to reduced photooxidation activity and significantly improved photostability. NPIR1116 exhibits strong NIR-II absorption and fluorescence, peaking at 1004 and 1116 nm, respectively, as well as a photothermal conversion efficiency of 79% under 1064 nm lasers. In vitro and in vivo studies showed the efficacy of NPIR1116 in tumor imaging via NIR-II fluorescence and its ability to effectively induce tumor cell apoptosis under 1064 nm laser irradiation. These findings underscore the potential of NPIR1116 in NIR-II fluorescence imaging-guided PTT for tumor treatment, paving the way for further advancements in NIR-II dye development and bioimaging technologies.

19F MRI/CEUS Dual Imaging-Guided Sonodynamic Therapy Enhances Immune Checkpoint Blockade in Triple-Negative Breast Cancer

Treatment of highly aggressive triple-negative breast cancer (TNBC) in the clinic is challenging. Here, a liposome nanodrug (LP@PFH@HMME) integrating imaging agents and therapeutic agents for bimodal imaging-guided sonodynamic therapy (SDT) is developed, which boosted immunogenicity to enable potent immunotherapy via immune checkpoint blockade (ICB) in TNBC. In the acidic tumor microenvironment (TME), LP@PFH@HMME undergoes "nano-to-micro" transformation due to a pH-responsive lipid fusion, which makes droplets much more sensitive to ultrasound (US) in contrast-enhanced ultrasound (CEUS) and SDT studies. The nanodrug demonstrates robust bimodal imaging ability through fluorine-19 magnetic resonance imaging (19F MRI) and CEUS bimodal imaging, and it exhibits excellent solubility in aqueous solution with relatively high 19F content and desirable long transverse relaxation time (T2 = 1.072 s), making it suitable for high-performance 19F MRI, in addition to effective accumulation of nanodrugs after tail vein injection. Thus, 19F MRI/CEUS dual imaging is achievable to show adequate time points for US irradiation of tumor sites to induce highly effective SDT, which produces abundant reactive oxygen species (ROS) triggering immunogenic cell death (ICD) to assist ICB-based immunotherapy. The combination treatment design of sonodynamic therapy with immunotherapy effectively inhibited TNBC growth and recurrence, highlighting the promise of multifunctional nanodrugs in treating TNBC.

Docetaxel-Encapsulated Catalytic Pt/Au Nanotubes for Synergistic Chemo-Photothermal Therapy of Triple-Negative Breast Cancer

The combination of photothermal therapy with chemotherapy has emerged as a promising therapeutic modality for addressing triple-negative breast cancer (TNBC). This manuscript describes a novel hybrid nanoplatform comprising ultrathin catalytic platinum/gold (Pt/Au) nanotubes encapsulated with docetaxel and phase-change materials (PCMs) for the photoacoustic imaging-guided synergistic chemo-photothermal therapy of TNBC. Upon irradiation of near-infrared laser, the photothermal heating of nanotubes converts solid-state PCM into liquid, triggering the controlled release of the encapsulated docetaxel. The thin Pt layer within nanotubes enhances the nanotube's thermal stability, thus prolonging the photothermal ablation of tumors. Furthermore, platinum effectively mitigates tumor hypoxia by catalyzing the decomposition of hydrogen peroxides to generate oxygen in the tumor microenvironment, thus improving the efficiency of chemotherapy. It is demonstrated that the drug-loaded nanotubes achieve significant tumor inhibition rates of 75.4% in vivo on 4T1 tumor-bearing mice, significantly surpassing control groups. These nanotubes also notably extend survival, attributable to the synergistic effects of prolonged photothermal therapy facilitated by platinum and oxygenation-enhanced chemotherapy. This combination leverages the unique properties of the Pt/Au NTs-DTX/PCM nanoplatform, optimizing therapeutic outcomes. It is envisioned that this nanoplatform may find important applications in managing superficial malignant solid tumors in general.

Cyanine dyes in the mitochondria-targeting photodynamic and photothermal therapy

Mitochondrial dysregulation plays a significant role in the carcinogenesis. On the other hand, its destabilization strongly represses the viability and metastatic potential of cancer cells. Photodynamic and photothermal therapies (PDT and PTT) target mitochondria effectively, providing innovative and non-invasive anticancer therapeutic modalities. Cyanine dyes, with strong mitochondrial selectivity, show significant potential in enhancing PDT and PTT. The potential and limitations of cyanine dyes for mitochondrial PDT and PTT are discussed, along with their applications in combination therapies, theranostic techniques, and optimal delivery systems. Additionally, novel approaches for sonodynamic therapy using photoactive cyanine dyes are presented, highlighting advances in cancer treatment.

Folic acid-mediated hollow Mn 3 O 4 nanocomposites for in vivo MRI/FLI monitoring the metastasis of gastric cancer

BACKGROUND

Metastasis is one of the main factors leading to the high mortality rate of gastric cancer. The current monitoring methods are not able to accurately monitor gastric cancer metastasis.

METHODS

In this paper, we constructed a new type of hollowMn 3 O 4 nanocomposites,Mn 3 O 4 @HMSN-Cy7.5-FA, which had a size distribution of approximately 100 nm and showed good stability in different liquid environments. The in vitro magnetic resonance imaging (MRI) results show that the nanocomposite has good response effects to the acidic microenvironment of tumors. The acidic environment can significantly enhance the contrast of T 1 -weighted MRI. The cellular uptake and endocytosis results show that the nanocomposite has good targeting capabilities and exhibits good biosafety, both in vivo and in vitro. In a gastric cancer nude mouse orthotopic metastatic tumor model, with bioluminescence imaging's tumor location information, we realized in vivo MRI/fluorescence imaging (FLI) guided precise monitoring of the gastric cancer orthotopic and metastatic tumors with this nanocomposite.

RESULTS

This report demonstrates thatMn 3 O 4 @HMSN-Cy7.5-FA nanocomposites is a promising nano-diagnostic platform for the precision diagnosis and therapy of gastric cancer metastasis in the future.

CONCLUSIONS

In vivo MRI/FLI imaging results show that the nanocomposites can achieve accurate monitoring of gastric cancer tumors in situ and metastases. BLI's tumor location information further supports the good accuracy of MRI/FLI dual-modality imaging. The above results show that the MHCF NPs can serve as a good nano-diagnostic platform for precise in vivo monitoring of tumor metastasis. This nanocomposite provides more possibilities for the diagnosis and therapy of gastric cancer metastases.

Development of Polymethine Dyes for NIR-II Fluorescence Imaging and Therapy

Fluorescence imaging in the second near-infrared window (NIR-II) is burgeoning because of its higher imaging fidelity in monitoring physiological and pathological processes than clinical visible/the second near-infrared window fluorescence imaging. Notably, the imaging fidelity is heavily dependent on fluorescence agents. So far, indocyanine green, one of the polymethine dyes, with good biocompatibility and renal clearance is the only dye approved by the Food and Drug Administration, but it shows relatively low NIR-II brightness. Importantly, tremendous efforts are devoted to synthesizing polymethine dyes for imaging preclinically and clinically. They have shown feasibility in the customization of structure and properties to fulfill various needs in imaging and therapy. Herein, a timely update on NIR-II polymethine dyes, with a special focus on molecular design strategies for fluorescent, photoacoustic, and multimodal imaging, is offered. Furthermore, the progress of polymethine dyes in sensing pathological biomarkers and even reporting drug release is illustrated. Moreover, the NIR-II fluorescence imaging-guided therapies with polymethine dyes are summarized regarding chemo-, photothermal, photodynamic, and multimodal approaches. In addition, artificial intelligence is pointed out for its potential to expedite dye development. This comprehensive review will inspire interest among a wide audience and offer a handbook for people with an interest in NIR-II polymethine dyes.

Photothermal therapy: a novel potential treatment for prostate cancer

Prostate cancer (PCa) is a leading cause of cancer-related death in men, and most PCa patients treated with androgen deprivation therapy will progress to metastatic castration-resistant prostate cancer (mCRPC) due to the lack of efficient treatment. Recently, lots of research indicated that photothermal therapy (PTT) was a promising alternative that provided an accurate and efficient prostate cancer therapy. A photothermic agent (PTA) is a basic component of PPT and is divided into organic and inorganic PTAs. Besides, the combination of PTT and other therapies, such as photodynamic therapy (PDT), immunotherapy (IT), chemotherapy (CT), etc., provides an more efficient strategy for PCa therapy. Here, we introduce basic information about PTT and summarize the PTT treatment strategies for prostate cancer. Based on recent works, we think the combination of PPT and other therapies provides a novel possibility for PCa, especially CRPC clinical treatment.

A mitochondrion-targeted cyanine agent for NIR-II fluorescence-guided surgery combined with intraoperative photothermal therapy to reduce prostate cancer recurrence

Poorly identified tumor boundaries and nontargeted therapies lead to the high recurrence rates and poor quality of life of prostate cancer patients. Near-infrared-II (NIR-II) fluorescence imaging provides certain advantages, including high resolution and the sensitive detection of tumor boundaries. Herein, a cyanine agent (CY7-4) with significantly greater tumor affinity and blood circulation time than indocyanine green was screened. By binding albumin, the absorbance of CY7-4 in an aqueous solution showed no effects from aggregation, with a peak absorbance at 830 nm and a strong fluorescence emission tail beyond 1000 nm. Due to its extended circulation time (half-life of 2.5 h) and high affinity for tumor cells, this fluorophore was used for primary and metastatic tumor diagnosis and continuous monitoring. Moreover, a high tumor signal-to-noise ratio (up to ~ 10) and excellent preferential mitochondrial accumulation ensured the efficacy of this molecule for photothermal therapy. Therefore, we integrated NIR-II fluorescence-guided surgery and intraoperative photothermal therapy to overcome the shortcomings of a single treatment modality. A significant reduction in recurrence and an improved survival rate were observed, indicating that the concept of intraoperative combination therapy has potential for the precise clinical treatment of prostate cancer.

Mitochondrial Disruption Nanosystem Simultaneously Depressed Programmed Death Ligand-1 and Transforming Growth Factor-β to Overcome Photodynamic Immunotherapy Resistance

Currently, limited photosensitizers possess the capacity to reverse tumor hypoxia and reduce programmed death ligand-1 (PD-L1) and transforming growth factor-β (TGF-β) expression simultaneously, hindering the perfect photodynamic therapy (PDT) effect due to acquired immune resistance and the tumor hypoxic microenvironment. To tackle these challenges, in this research, we demonstrated that mitochondrial energy metabolism depression can be utilized as an innovative and efficient approach for reducing the expression of PD-L1 and TGF-β simultaneously, which may offer a design strategy for a more ideal PDT nanosystem. Through proteomic analysis of 5637 cells, we revealed that tamoxifen (TMX) can incredibly regulate PD-L1 expression in tumor cells. Then, to selectively deliver clinically used mitochondrial energy metabolism depressant TMX to solid tumors as well as design an ideal PDT nanosystem, we synthesized MHI-TMX@ALB by combining a mitochondria-targeted heptamethine cyanine PDT-dye MHI with TMX through self-assembly with albumin (ALB). Interestingly enough, the MHI-TMX@ALB nanoparticle demonstrated effective reversion of tumor hypoxia and inhibition of PD-L1 protein expression at a lower dosage (7.5 times to TMX), which then enhanced the efficacy of photodynamic immunotherapy via enhancing T-cell infiltration. Apart from this, by leveraging the heptamethine dye's targeting capacity toward tumors and TMX's role in suppressing TGF-β, MHI-TMX@ALB also more effectively mitigated 4T1 tumor lung metastasis development. All in all, the MHI-TMX@ALB nanoparticle could be used as a multifunctional economical PD-L1 and TGF-β codepression immune-regulating strategy, broadening the potential clinical applications for a more ideal PDT nanosystem.