ROS Responsive Nanoparticles Encapsulated with Natural Medicine Remodel Autophagy Homeostasis in Breast Cancer.

In photodynamic therapy (PDT), elevated reactive oxygen species (ROS) activate tumor cell protective autophagy, therefore attenuating the antitumor function of therapy. Hence, inhibition of protective autophagy in tumors can improve the antitumor effect of PDT. Herein, an innovative nanotraditional Chinese medicine system ((TP+A)@TkPEG NPs), which remodeled autophagy homeostasis, was fabricated. A photosensitizer aggregation inducing emission (AIE) and autophagy modulator triptolide (TP, an active ingredient of Tripterygium wilfordii Hook F) were encapsulated into ROS-responsive nanoparticles to improve antitumor effect of PDT in treatment of triple negative breast cancer. We proved that (TP+A)@TkPEG NPs effectively elevated intracellular ROS levels, activated ROS-responsive release of TP and inhibited the proliferation of 4T1 cells in vitro. More importantly, it sharply reduced autophagy related genes transcription and proteins expression in 4T1 cells, then promote cell apoptosis. In addition, this nanoherb therapeutic system effectively orientated to tumor sites, achieved efficient inhibition of tumor, and extended the survival time of 4T1-bearing mice in vivo. Further results confirmed that (TP+A)@TkPEG NPs remarkably inhibit the expression level of autophagy related initiation gene (becline-1) and elongation protein (light chain 3B) in tumor microenvironment and then block PDT induced protective autophagy. In brief, this system can remodel autophagy homeostasis and serve as an innovative approach for treatment of triple negative breast cancer.

Nano-traditional Chinese medicine: a promising strategy and its recent advances.

Traditional Chinese Medicine (TCM) has been applied to the prevention and treatment of numerous diseases and has an irreplaceable role in rehabilitation and health care. However, the application of TCMs is drastically limited by their defects, such as single administration, poor water solubility, low bioavailability, and weak targeting capability. Recently, nanoparticles have been extensively used in resolving pharmaceutical obstacles in consideration of their large specific surface area, strong targeting capability, good sustained-release effect, etc. In this review, we first describe the limitations of TCM ingredients and two significant forms of nanotechnology applied in TCM, nanometerization of TCMs and nano-drug delivery systems for TCMs. Then, we discuss the preparation methods of nanometerization: mechanical crushing, spray drying, and high-pressure homogenization, which have been utilized to conquer the various weaknesses of TCMs. Then, recent advances in nano-drug delivery systems for TCM ingredients are discussed, including lipid-based nanocarriers, polymeric nanoparticles, inorganic nanocarriers, hybrid nanoparticles, and TCM self-assembled nanoparticles. Finally, the future challenges and perspectives of TCM formula complexity and the limitations of nanocarriers are also discussed. Better understanding the function of nanotechnology in TCM will help to modernize Chinese medicine and broaden the application of nano-TCM in the clinic.

Nano-herb medicine and PDT induced synergistic immunotherapy for colon cancer treatment.

A variety of therapies have been developed and used for the treatment of colon cancer, however, the high mortality rate remains high and more effective strategies are still in urgent needs. In this study, an immunotherapy approach that is composed of innate immune activator Astragaloside III (As) and the photodynamic therapy (PDT) reagent chlorine e6 (Ce6) ((As + Ce6)@MSNs-PEG), was developed for colon cancer treatment. We showed that (As + Ce6)@MSNs-PEG could effectively activate NK cells and inhibit the proliferation of tumor cells in vitro. It could also effectively reach tumor sites, induce infiltration of immune cells into the tumor, and enhance the cytotoxicity of natural killer cells and CD8+ T cells in vivo. Without obvious side effects, (As + Ce6)@MSNs-PEG treatment significantly inhibited tumor growth and extended the lifespan of tumor-bearing mice. Further results revealed that treatment of (As + Ce6)@MSNs-PEG led to enhanced IFN secretion by immune cells and increased T-box transcription factor (T-bet), which is highly expressed by T cells. Therefore, (As + Ce6)@MSNs-PEG may serve as an effective and safe platform for combinatory use with nano-herb medicine and PDT to provide a new therapy for colon cancer treatment.

Immune Modulator and Low-Temperature PTT-Induced Synergistic Immunotherapy for Cancer Treatment.

Immunotherapy has shown great potential in cancer therapeutics but has limitations of the insufficient activation of dendritic cells (DCs) and immune-suppressive microenvironment. To overcome these obstacles, a cascade synergistic immunotherapy nanosystem (denoted as CpG@PDA-FA) was designed to elevate anticancer immune response. The combination nanosystem including a photothermal agent polydopamine (PDA) and immunomodulator CpG oligodeoxynucleotides (CpG ODNs). On the one hand, polydopamine (PDA) acts as a photothermal agent to induce low-temperature PTT. It leads to immunogenic cell death (ICD), a programmed cell death pathway, which can activate DCs and enhance the antitumor immune response of T cells. On the other hand, CpG ODNs further promote maturation and migration of DCs as well as ameliorates the immunosuppression microenvironment of the tumor (TME). This paper focuses on a cancer synergistic treatment of ICD-induced immunotherapy by low-temperature PTT and ameliorates TME by immunomodulator CpG ODNs. We proved that CpG@PDA-FA NPs realized a remarkable synergistic treatment effect compared with respective single PTT or CpG therapy in the maturation of DCs and activation of T cells. In addition, CpG@PDA-FA NPs also reduced myeloid-derived suppressor cells and regulatory T cells to relieve immunosuppression. Hence, CpG@PDA-FA NPs provide a bidirectional immunotherapy strategy for tumor inhibition and highlight the cascade effects of low-temperature PTT and immunotherapy.

Mitochondria-targeted nanoparticles in treatment of neurodegenerative diseases.

Neurodegenerative diseases (NDs) are a class of heterogeneous diseases that includes Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis. Mitochondria play an important role in oxidative balance and metabolic activity of neurons; therefore, mitochondrial dysfunction is associated with NDs and mitochondria are considered a potential treatment target for NDs. Several obstacles, including the blood-brain barrier (BBB) and cell/mitochondrial membranes, reduce the efficiency of drug entry into the target lesions. Therefore, a variety of neuron mitochondrial targeting strategies has been developed. Among them, nanotechnology-based treatments show especially promising results. Owing to their adjustable size, appropriate charge, and lipophilic surface, nanoparticles (NPs) are the ideal theranostic system for crossing the BBB and targeting the neuronal mitochondria. In this review, we discussed the role of dysfunctional mitochondria in ND pathogenesis as well as the physiological barriers to various treatment strategies. We also reviewed the use and advantages of various NPs (including organic, inorganic, and biological membrane-coated NPs) for the treatment and diagnosis of NDs. Finally, we summarized the evidence and possible use for the promising role of NP-based theranostic systems in the treatment of mitochondrial dysfunction-related NDs.

A Novel Targeted and High-Efficiency Nanosystem for Combinational Therapy for Alzheimer's Disease.

Alzheimer's disease (AD) remains the most prevalent neurodegenerative disease, and no effective treatment is available yet. Metal-ion-triggered aggregates of amyloid-beta (Aß) peptide and acetylcholine imbalance are reported to be possible factors in AD pathogenesis. Thus, a combination therapy that can not only inhibit and reduce Aß aggregation but also simultaneously regulate acetylcholine imbalance that can serve as a potential treatment for AD is needed. Here, clioquinol (metal-ion chelating agent) and donepezil (acetylcholinesterase (AChE) inhibitor) co-encapsulated human serum albumin (HSA) nanoparticles (dcHGT NPs) are designed, which are modified with transcriptional activator protein (TAT) and monosialotetrahexosylganglioside (GM1). The GM1 lipid and TAT peptide endow this drug delivery nanosystem with high brain entry efficiency and long-term retention capabilities through intranasal administration. It is found that dcHGT NPs can significantly inhibit and eliminate Aß aggregation, relieve acetylcholine-related inflammation in microglial cells, and protect primary neurons from Aß oligomer-induced neurotoxicity in vitro. The alleviation of Aß-related inflammation and AChE-inhibited effect further synergistically adjust acetylcholine imbalance. It is further demonstrated that dcHGT NPs reduce Aß deposition, ameliorate neuron morphological changes, rescue memory deficits, and greatly improve acetylcholine regulation ability in vivo. This multifunctional synergetic nanosystem can be a new candidate to achieve highly efficient combination therapy for AD.

Correction: An NIR-responsive mesoporous silica nanosystem for synergetic photothermal-immunoenhancement therapy of hepatocellular carcinoma.

Correction for 'An NIR-responsive mesoporous silica nanosystem for synergetic photothermal-immunoenhancement therapy of hepatocellular carcinoma' by Han Yang et al., J. Mater. Chem. B, 2020, 8, 251-259.

An NIR-responsive mesoporous silica nanosystem for synergetic photothermal-immunoenhancement therapy of hepatocellular carcinoma.

To create a more precise, efficient imaging and therapeutic strategy is a big challenge for the current treatment of hepatocellular carcinoma (HCC). Photothermal therapy (PTT) has attracted enormous attention due to its non-invasive property and precise spatial and temporal control. Here, we developed a strategy to realize superior imaging performance and treatment, utilizing an indocyanine green (ICG) and sorafenib (S) co-loaded mesoporous silica nanosystem for synergetic PTT/immuno-enhanced therapy. We proved that (ICG+S)@mSiO2 could be easily endocytosed by H22 cells, carried out outstanding real-time fluorescence imaging, and enhanced cytotoxicity abilities by near-infrared radiation (NIR) in vitro. Moreover, (ICG+S)@mSiO2 also had excellent fluorescence imaging ability, displayed a remarkable photothermal tumor killing effect and immune enhancement capability under 808 nm irradiation in an H22 tumor-bearing mice model, without apparent adverse effects in other organs. This study provides a new strategy for the development of a PTT/immuno-enhanced synergistic theranostic nanosystem of HCC.

Nanoparticle-based diagnostic and therapeutic systems for brain tumors.

Brain tumors, especially the most prevalent and aggressive glioblastoma, remain among the deadliest of all types of cancer due to inefficient theranostic options. They have a limited therapeutic window because of physiological barriers such as the blood-brain barrier (BBB), blood cerebrospinal fluid (CSF) barrier and interstitial fluid (ISF) that restrict the penetration of imaging probes and therapeutic drugs. In order to achieve more accurate brain tumor diagnosis and better therapeutic effects, many strategies have been explored; among them multifunctional nanoparticles offer a novel and potential opportunity depending on their size effects, and their optical, magnetic, photodynamic and other properties. After modification, nanoparticles can cross the BBB and specifically accumulate in the tumor site, thereby achieving accurate tumor imaging and drug release. This review is focused on various types of nanoparticles that are being used for improving nano-carriers of diagnostic and therapeutic agents into brain tumors and also provides a concise summary of various multifunctional theranostic strategies, particularly in clinical applications. In this manner, we provide evidence for the key role of nanoparticle based diagnosis and therapy systems in brain tumors.