Polymer micro/nanocarrier-assisted synergistic chemohormonal therapy for prostate cancer

A quaternary ammonium-based nanosystem enables delivery of CRISPR/Cas9 for cancer therapy

Genome editing mediated by CRISPR/Cas9 is an attractive weapon for cancer therapy. However, in vivo delivery of CRISPR/Cas9 components to achieve therapeutic efficiency is still challenging. Herein, a quaternary ammonium-functionalized poly(L-lysine) and a cholesterol-modified PEG (QNP) were self-assembled with a negatively charged CRISPR Cas9/sgRNA ribonucleoprotein (RNP) to form a ternary complex (QNP/RNP). Such a delivery system of QNP exhibited multiplex genome editing capabilities in vitro (e.g., the GFP gene and the PLK1 gene). In addition, QNP/RNPPLK1 containing PLK1 sgRNA led to 30.99% of genome editing efficiency in MCF-7 cells with negligible cytotoxicity of the carrier. QNP/RNPPLK1, which was capable of simultaneously inhibiting cell proliferation, mediating cell cycle arrest and downregulating expression of PLK1, held great in vitro therapeutic efficiency. Moreover, QNP/RNPPLK1 exhibited outstanding accumulation in tumors and high biocompatibility in vivo. In an MCF-7 xenograft animal model, QNP/RNPPLK1 showed excellent anti-tumor efficacy and achieved 17.75% indels ratio. This work showcases the successful delivery of CRISPR Cas9/sgRNA RNP with enhanced genome editing efficiency and provides a potential on-demand strategy for cancer therapy.

Multifunctional nano-system for multi-mode targeted imaging and enhanced photothermal therapy of metastatic prostate cancer

Prostate cancer (PCa) routinely employs magnetic resonance (MR) imaging, while metastatic PCa needs more complicated detection methods for precise localization. The inconvenience of using different methods to detect PCa and its metastases in patients and the limitations of single-mode imaging have brought great challenges to clinicians. Meanwhile, clinical treatments for metastatic PCa are still limited. Herein, we report a targeted theranostic platform of Au/Mn nanodots-luteinising hormone releasing hormone (AMNDs-LHRH) nano-system for multi-mode imaging guided photothermal therapy of PCa. The nano-system not only can simultaneously target Gonadotropin-Releasing Hormone Receptor (GnRH-R) positive PCa and its metastases for accurate preoperative CT/MR diagnosis, but also possesses fluorescence (FL) visualization navigated surgery, demonstrating its potential application in clinical cancer detection and surgery guidance. Meanwhile, the AMNDs-LHRH with promising targeting and photothermal conversion ability significantly improve the photothermal therapy effect of metastatic PCa. The AMNDs-LHRH nano-system guarantees the diagnostic accuracy and enhanced therapeutic effect, which provides a promising platform for clinical diagnosis and treatment of metastatic PCa. STATEMENT OF SIGNIFICANCE: Accurate clinical diagnosis and treatment of prostate cancer and its metastases is challenging. A targeted theranostic platform of AMNDs-LHRH nano-system for multi-mode imaging (FL/CT/MR) guided photothermal therapy of metastatic prostate cancer has been reported. The nano-system not only can simultaneously target prostate cancer and its metastases for accurate preoperative CT/MR diagnosis, but also possesses fluorescence visualization navigated surgery, demonstrating its potential application in clinical cancer detection and surgery guidance. The nano-system with great targeting and photothermal conversion ability significantly improve the photothermal therapy effect of metastatic prostate cancer. Overall, the AMNDs-LHRH nano-system integrates tumor targeting, multi-mode imaging and enhanced therapeutic effect, which can provide an effective strategy for the clinical diagnosis and treatment of metastatic PCa.

Multifunctional nanoprobe for multi-mode imaging and diagnosis of metastatic prostate cancer

The high incidence and complex subtypes of prostate cancer put forward higher requirements for accurate diagnosis. Furthermore, advanced prostate cancer is prone to metastasis. Single biological imaging mode faces a challenge of sensitive and fast bioimaging of metastasic prostate cancer. Thus, exploring a nanoprobe with multi-mode imaging function has an important impact on preoperative imaging and intraoperative visualization guide of metastatic prostate cancer. Herein, based on the optical properties and X-ray attenuation capability of Au nanodots as well as the slow electronic relaxation of Gd³⁺, we designed and fabricated the multifunctional nanoprobe Au/Gd nanodots for multi-mode imaging and accurate diagnosis of bone metastatic prostate cancer. The results showed that multiple imaging modes complement each other to achieve high-precision of metastasic prostate cancer detection and accurately guide treatment. In addition, in vitro/vivo experiments showed that Au/Gd nanodots had good biocompatibility and biosafety. Therefore, the prepared multifunctional nanoprobe may provide new strategies and insights for precise diagnosis of metastatic prostate cancer in clinical practice.

Immunomodulatory nanosystems: An emerging strategy to combat viral infections

The viral infection spreads with the assistance of a host. Traditional antiviral therapies cannot provide long-term immunity against emerging and drug-resistant viral infections. Immunotherapy has evolved as an efficient approach for disease prevention and treatment, which include cancer, infections, inflammatory, and immune disorders. Immunomodulatory nanosystems can dramatically enhance therapeutic outcomes by combating many therapeutic challenges, such as poor immune stimulation and off-target adverse effects. Recently, immunomodulatory nanosystems have emerged as a potent antiviral strategy to intercept viral infections effectively. This review introduces major viral infections with their primary symptoms, route of transmission & targeted organ, and different stages of the viral life cycle with respective traditional blockers. The IMNs have an exceptional capacity for precisely modulating the immune system for therapeutic applications. The nano sized immunomodulatory systems permit the immune cells to interact with infectious agents enhancing lymphatic drainage and endocytosis by the over-reactive immune cells in the infected areas. Immune cells that can be modulated upon viral infection via various immunomodulatory nanosystems have been discussed. Advancement in theranostics can yield an accurate diagnosis, adequate treatment, and real-time screening of viral infections. Nanosystem-based drug delivery can continue to thrive in diagnosing, treating, and preventing viral infections. The curative medicine for remerging and drug-resistant viruses remains challenging, though certain systems have expanded our perception and initiated a new research domain in antiviral treatments.

AuNCs-LHRHa nano-system for FL/CT dual-mode imaging and photothermal therapy of targeted prostate cancer

As the most common cancer in men worldwide, prostate cancer has a serious impact on people's health. Until now, the development of a platform for integrating tumor targeting, imaging and an effective treatment for prostate cancer has remained challenging. Herein, a nano-system is designed to improve both diagnosis and treatment for prostate cancer. We successfully synthesized an AuNCs-LHRHa nano-system by combining PEI-modified gold nanoclusters (AuNCs) with LHRH analogues (LHRHa). Due to the good tunable optical properties and photothermal properties of AuNCs, the nano-system can not only achieve efficient fluorescence/computed tomography dual-mode imaging, but can also be used for photothermal therapy (PTT). After modifying the LHRHa antibody of a prostate tumor, AuNCs-LHRHa can be more effectively recognized by the gonadotropin-releasing hormone receptors (GnRH-R) on the membrane of RM-1 cells, enhancing the tumor cell uptake of the nano-system, improving the targeting accuracy and PTT therapy efficacy for prostate cancer. It is hoped that the nano-system, which combines dual-mode imaging and targeted therapy, will provide a promising strategy for the integration of FL/CT diagnosis and PTT therapy for GnRH-R positive prostate cancer.

Aptamers: an emerging navigation tool of therapeutic agents for targeted cancer therapy

Chemotherapeutic agents have been used for the treatment of numerous cancers, but due to poor selectivity and severe systemic side effects, their clinical application is limited. Single-stranded DNA (ssDNA) or RNA aptamers could conjugate with highly toxic chemotherapy drugs, toxins, therapeutic RNAs or other molecules as novel aptamer-drug conjugates (ApDCs), which are capable of significantly improving the therapeutic efficacy and reducing the systemic toxicity of drugs and have great potential in clinics for targeted cancer therapy. In this review, we have comprehensively discussed and summarized the current advances in the screening approaches of aptamers for specific cancer biomarker targeting and development of the aptamer-drug conjugate strategy for targeted drug delivery. Moreover, considering the huge progress in artificial intelligence (AI) for protein and RNA structure predictions, automatic design of aptamers using deep/machine learning techniques could be a powerful approach for rapid and precise construction of biopharmaceutics (i.e., ApDCs) for application in cancer targeted therapy.

Stimuli-responsive polypeptides for controlled drug delivery

Controlled drug delivery systems, which could release loaded therapeutics upon physicochemical changes imposed by physiological triggers in the desired zone and during the required period of time, offer numerous advantages over traditional drug carriers including enhanced therapeutic effects and reduced toxicity. A polypeptide is a biocompatible and biodegradable polymer, which can be conveniently endowed with stimuli-responsiveness by introducing natural amino acid residues with innate stimuli-responsive characteristics or introducing responsive moieties to its side chains using simple conjugating methods, rendering it an ideal biomedical material for controlled drug delivery. This feature article summarizes our recent work and other relevant studies on the development of polypeptide-based drug delivery systems that respond to single or multiple physiological stimuli (e.g., pH, redox potential, glucose, and hypoxia) for controlled drug delivery applications. The material designs, synthetic strategies, loading and controlled-release mechanisms of drugs, and biomedical applications of these stimuli-responsive polypeptides-based drug delivery systems are elaborated. Finally, the challenges and opportunities in this field are briefly discussed.

Inhalable nanovaccine with biomimetic coronavirus structure to trigger mucosal immunity of respiratory tract against COVID-19

The COVID-19 pandemic caused by SARS-CoV-2 seriously threatens global public health. It has previously been confirmed that SARS-CoV-2 is mainly transmitted between people through "respiratory droplets". Therefore, the respiratory tract mucosa is the first barrier to prevent virus invasion. It is very important to stimulate mucosal immunity to protect the body from respiratory virus infection. Inspired by this, we designed a bionic-virus nanovaccine, which can induce mucosal immunity by nasal delivery to prevent virus infection from respiratory tract. The nanovaccine that mimic virosome is composed of poly(I:C) mimicking viral genetic material as immune adjuvant, biomimetic pulmonary surfactant (bio-PS) liposomes as capsid structure of virus and the receptor binding domains (RBDs) of SARS-CoV-2 as "spike" to completely simulate the structure of the coronavirus. The nanovaccine can be administered by inhaling to imitate the process of SARS-CoV-2 infection through the respiratory tract. Our results demonstrated that the inhalable nanovaccine with bionic virus-like structure has a stronger mucosal protective effect than routine muscle and subcutaneous inoculation. In particular, high titer of secretory immunoglobulin A (sIgA) was detected in respiratory secretions, which effectively neutralize the virus and prevent it from entering the body through the respiratory tract. Through imitating the structure and route of infection, this inhalable nanovaccine strategy might inspire a new approach to the precaution of respiratory viruses.

Polypeptide-based drug delivery systems for programmed release

Recent years have seen increasing interests in the use of ring-opening polymerization of α-amino acid N-carboxyanhydrides (NCAs) to prepare synthetic polypeptides, a class of biocompatible and versatile materials, for various biomedical applications. Because of their rich side-chain functionalities, diverse hydrophilicity/hydrophobicity profiles, and the capability of forming stable secondary structures, polypeptides can assemble into a variety of well-organized nano-structures that have unique advantages in drug delivery and controlled release. Herein, we review the design and use of polypeptide-based drug delivery system derived from NCA chemistry, and discuss the future perspectives of this exciting and important biomaterial area that may potentially change the landscape of next-generation therapeutics and diagnosis. Given the high significance of precise control over release for polypeptide-based systems, we specifically focus on the versatile designs of drug delivery systems capable of programmed release, through the changes in the chemical and physical properties controlled by the built-in molecular structures of polypeptides.

Morphology, Loadability, and Releasing Profiles of CalliSpheres Microspheres in Delivering Oxaliplatin: An In Vitro Study

Objectives:

This study aimed to explore the morphology, loadability, and releasing profiles of CalliSpheres microspheres in delivering oxaliplatin.

Methods:

Varied amount (20, 40, 60, and 80 mg oxaliplatin) and concentration (1.25, 2.5, 5.0 mg/mL oxaliplatin) of oxaliplatin were mixed with CalliSpheres microspheres with 3 sizes (50-150 μm, 100-300 μm, and 300-500 μm) to measure the loadability. Of all, 20 mg oxaliplatin-loaded CalliSpheres microspheres with 3 sizes was prepared to measure the releasing profiles, meanwhile, fetal bovine serum was added to determine the effect of serum on oxaliplatin releasing. The morphology and size distribution of CalliSpheres microspheres with 3 sizes before and after 20 mg oxaliplatin loading were detected.

Results:

Oxaliplatin amount was negatively correlated with loading efficiency with highest loadability in 20 mg oxaliplatin group (maximum 40% in 50-100 µm CalliSpheres microspheres, 52% in 100-300 µm CalliSpheres microspheres, and 52% in 300-500 µm CalliSpheres microspheres), while oxaliplatin concentration was positively associated with loading efficiency. Similar drug-releasing profiles were observed among oxaliplatin-loaded CalliSpheres microspheres with 3 sizes, and a rapid drug release was discovered in CalliSpheres microspheres with 3 sizes as well. We also found that fetal bovine serum did not affect the drug-releasing profiles of oxaliplatin-loaded CalliSpheres microspheres. In addition, CalliSpheres microspheres was modified a little to ellipse shape and less smooth after oxaliplatin loading, and it was enlarged to some extent.

Conclusion:

This study discloses drug loadability, releasing profiles, and morphology change of CalliSpheres microspheres for delivering oxaliplatin, which provides potential evidences for application of oxaliplatin-loaded drug-eluting beads in clinical practice.

Intratumoral delivery of M-CSF by calcium crosslinked polymer micelles enhances cancer immunotherapy

Immunotherapy has shown promising results in multiple malignancies. However, there are still significant challenges in cancer immunotherapy including the powerful immunosuppressive tumor microenvironment and adverse off-target side effects. Nanomaterials with defined physico-biochemical properties are versatile drug delivery platforms that may address these key technical challenges faced by cancer immunotherapy. Here, a tumor acidity-responsive biomacromolecule delivery system was designed to intratumorally deliver an immune-activating cytokine, macrophage colony-stimulating factor (M-CSF) and attenuate the acidic microenvironment. This nanoparticle was prepared by introducing CaCO3 as a crosslinker to form an M-CSF-loaded stable micelle (NP/M-CSF/CaCO3). Administration of NP/M-CSF/CaCO3 significantly inhibited tumor growth by enhancing T cell-mediated anti-tumor immune responses and reversing the TAM-mediated immunosuppression. This study provides new avenues for cascade amplification of the antitumor effects by targeting the tumor microenvironment. This approach may also help avoid unwanted complications.

Immunomodulatory Nanosystems

Immunotherapy has emerged as an effective strategy for the prevention and treatment of a variety of diseases, including cancer, infectious diseases, inflammatory diseases, and autoimmune diseases. Immunomodulatory nanosystems can readily improve the therapeutic effects and simultaneously overcome many obstacles facing the treatment method, such as inadequate immune stimulation, off-target side effects, and bioactivity loss of immune agents during circulation. In recent years, researchers have continuously developed nanomaterials with new structures, properties, and functions. This Review provides the most recent advances of nanotechnology for immunostimulation and immunosuppression. In cancer immunotherapy, nanosystems play an essential role in immune cell activation and tumor microenvironment modulation, as well as combination with other antitumor approaches. In infectious diseases, many encouraging outcomes from using nanomaterial vaccines against viral and bacterial infections have been reported. In addition, nanoparticles also potentiate the effects of immunosuppressive immune cells for the treatment of inflammatory and autoimmune diseases. Finally, the challenges and prospects of applying nanotechnology to modulate immunotherapy are discussed.