Recent advances in functionalized upconversion nanoparticles for light-activated tumor therapy

Borate bonds-containing pH-responsive chitosan hydrogel for postoperative tumor recurrence and wound infection prevention

Chitosan has been widely used in biomedical fields due to its good antibacterial properties, excellent biocompatibility, and biodegradability. In this study, a pH-responsive and self-healing hydrogel was synthesized from 3-carboxyphenylboronic acid grafted with chitosan (CS-BA) and polyvinyl alcohol (PVA). The dynamic boronic ester bonds and intermolecular hydrogen bonds are responsible for the hydrogel formation. By changing the mass ratio of CS-BA and PVA, the tensile stress and compressive stress of hydrogel can controlled in the range of 0.61 kPa - 0.74 kPa and 295.28 kPa - 1108.1 kPa, respectively. After doping with tannic acid (TA)/iron nanocomplex (TAFe), the hydrogel successful killed tumor cells through the near infrared laser-induced photothermal conversion and the TAFe-triggered reactive oxygen species generation. Moreover, the photothermal conversion of the hydrogel and the antibacterial effect of CS and TA give the hydrogel a good antibacterial effect. The CS-BA/PVA/TAFe hydrogel exhibit good in vivo and in vitro anti-tumor recurrence and antibacterial ability, and therefore has the potential to be used as a powerful tool for the prevention of local tumor recurrence and bacterial infection after surgery.

Temoporfin-Conjugated PEGylated Poly(N,N-dimethylacrylamide)-Coated Upconversion Colloid for NIR-Induced Photodynamic Therapy of Pancreatic Cancer

Photodynamic therapy (PDT) has the potential to cure pancreatic cancer with minimal side effects. Visible wavelengths are primarily used to activate hydrophobic photosensitizers, but in clinical practice, these wavelengths do not sufficiently penetrate deeper localized tumor cells. In this work, NaYF4:Yb3+,Er3+,Fe2+ upconversion nanoparticles (UCNPs) were coated with polymer and labeled with meta-tetra(hydroxyphenyl)chlorin (mTHPC; temoporfin) to enable near-infrared light (NIR)-triggered PDT of pancreatic cancer. The coating consisted of alendronate-terminated poly[N,N-dimethylacrylamide-co-2-aminoethylacrylamide]-graft-poly(ethylene glycol) [P(DMA-AEM)-PEG-Ale] to ensure the chemical and colloidal stability of the particles in aqueous physiological fluids, thereby also improving the therapeutic efficacy. The designed particles were well tolerated by the human pancreatic adenocarcinoma cell lines CAPAN-2, PANC-1, and PA-TU-8902. After intratumoral injection of mTHPC-conjugated polymer-coated UCNPs and subsequent exposure to 980 nm NIR light, excellent PDT efficacy was achieved in tumor-bearing mice.

Comparison of the Differences between Two-Photon Excitation, Upconversion, and Conventional Photodynamic Therapy on Cancers in In Vitro and In Vivo Studies

Photodynamic therapy (PDT) is a minimally invasive treatment for several diseases. It combines light energy with a photosensitizer (PS) to destroy the targeted cells or tissues. A PS itself is a non-toxic substance, but it becomes toxic to the target cells through the activation of light at a specific wavelength. There are some limitations of PDT, although it has been used in clinical studies for a long time. Two-photon excitation (TPE) and upconversion (UC) for PDT have been recently developed. A TPE nanoparticle-based PS combines the advantages of TPE and nanotechnology that has emerged as an attractive therapeutic agent for near-infrared red (NIR) light-excited PDT, whilst UC is also used for the NIR light-triggered drug release, activation of 'caged' imaging, or therapeutic molecules during PDT process for the diagnosis, imaging, and treatment of cancers.

METHODS

Nine electronic databases were searched, including WanFang Data, PubMed, Science Direct, Scopus, Web of Science, Springer Link, SciFinder, and China National Knowledge Infrastructure (CNKI), without any language constraints. TPE and UCNP were evaluated to determine if they had different effects from PDT on cancers. All eligible studies were analyzed and summarized in this review.

RESULTS

TPE-PDT and UCNP-PDT have a high cell or tissue penetration ability through the excitation of NIR light to activate PS molecules. This is much better than the conventional PDT induced by visible or ultraviolet (UV) light. These studies showed a greater PDT efficacy, which was determined by enhanced generation of reactive oxygen species (ROS) and reduced cell viability, as well as inhibited abnormal cell growth for the treatment of cancers.

CONCLUSIONS

Conventional PDT involves Type I and Type II reactions for the generation of ROS in the treatment of cancer cells, but there are some limitations. Recently, TPE-PDT and UCNP-PDT have been developed to overcome these problems with the help of nanotechnology in in vitro and in vivo studies.

Nanotechnology Utilizing Ferroptosis Inducers in Cancer Treatment

Current cancer treatment options have presented numerous challenges in terms of reaching high efficacy. As a result, an immediate step must be taken to create novel therapies that can achieve more than satisfying outcomes in the fight against tumors. Ferroptosis, an emerging form of regulated cell death (RCD) that is reliant on iron and reactive oxygen species, has garnered significant attention in the field of cancer therapy. Ferroptosis has been reported to be induced by a variety of small molecule compounds known as ferroptosis inducers (FINs), as well as several licensed chemotherapy medicines. These compounds' low solubility, systemic toxicity, and limited capacity to target tumors are some of the significant limitations that have hindered their clinical effectiveness. A novel cancer therapy paradigm has been created by the hypothesis that ferroptosis induced by nanoparticles has superior preclinical properties to that induced by small drugs and can overcome apoptosis resistance. Knowing the different ideas behind the preparation of nanomaterials that target ferroptosis can be very helpful in generating new ideas. Simultaneously, more improvement in nanomaterial design is needed to make them appropriate for therapeutic treatment. This paper first discusses the fundamentals of nanomedicine-based ferroptosis to highlight the potential and characteristics of ferroptosis in the context of cancer treatment. The latest study on nanomedicine applications for ferroptosis-based anticancer therapy is then highlighted.

Bioorthogonal chemistry for prodrug activation in vivo

Prodrugs have emerged as a major strategy for addressing clinical challenges by improving drug pharmacokinetics, reducing toxicity, and enhancing treatment efficacy. The emergence of new bioorthogonal chemistry has greatly facilitated the development of prodrug strategies, enabling their activation through chemical and physical stimuli. This "on-demand" activation using bioorthogonal chemistry has revolutionized the research and development of prodrugs. Consequently, prodrug activation has garnered significant attention and emerged as an exciting field of translational research. This review summarizes the latest advancements in prodrug activation by utilizing bioorthogonal chemistry and mainly focuses on the activation of small-molecule prodrugs and antibody-drug conjugates. In addition, this review also discusses the opportunities and challenges of translating these advancements into clinical practice.

Current State of Human Gene Therapy: Approved Products and Vectors

In the realm of gene therapy, a pivotal moment arrived with Paul Berg's groundbreaking identification of the first recombinant DNA in 1972. This achievement set the stage for future breakthroughs. Conditions once considered undefeatable, like melanoma, pancreatic cancer, and a host of other ailments, are now being addressed at their root cause-the genetic level. Presently, the gene therapy landscape stands adorned with 22 approved in vivo and ex vivo products, including IMLYGIC, LUXTURNA, Zolgensma, Spinraza, Patisiran, and many more. In this comprehensive exploration, we delve into a rich assortment of 16 drugs, from siRNA, miRNA, and CRISPR/Cas9 to DNA aptamers and TRAIL/APO2L, as well as 46 carriers, from AAV, AdV, LNPs, and exosomes to naked mRNA, sonoporation, and magnetofection. The article also discusses the advantages and disadvantages of each product and vector type, as well as the current challenges faced in the practical use of gene therapy and its future potential.

Dual-Site Förster Resonance Energy Transfer Route of Upconversion Nanoparticles-Based Brain-Targeted Nanotheranostic Boosts the Near-Infrared Phototherapy of Glioma

Glioblastoma multiforme (GBM) is the most common malignant brain tumor with low survival, primarily due to the blood-brain barrier (BBB) and high infiltration. Upconversion nanoparticles (UCNPs)-based near-infrared (NIR) phototherapy with deep penetration is a promising therapy method against glioma but faces low photoenergy utilization that is induced by spectral mismatch and single-site Förster resonance energy transfer (FRET). Herein, we designed a brain-targeting NIR theranostic system with a dual-site FRET route and superior spectral matching to maximize energy utilization for synergistic photodynamic and photothermal therapy of glioma. The system was fabricated by Tm-doped UCNPs, zinc tetraphenylporphyrin (ZnTPP), and copper sulfide (CuS) nanoparticles under multioptimized modulation. First, the Tm-doping ratio was precisely adjusted to improve the relative emission intensity at 475 nm of UCNPs (11.5-fold). Moreover, the J-aggregate of ZnTPP increased the absorption at 475 nm (163.5-fold) of monomer; both together optimize the FRET matching between UCNPs and porphyrin for effective NIR photodynamic therapy. Simultaneously, the emission at 800 nm was utilized to magnify the photothermal effect of CuS nanoparticles for photothermal therapy via the second FRET route. After being modified by a brain-targeted peptide, the system efficiently triggers the synergistic phototherapy ablation of glioma cells and significantly prolongs the survival of orthotopic glioma-bearing mice after traversing the BBB and targeting glioma. This success of advanced spectral modulation and dual-site FRET strategy may inspire more strategies to maximize the photoenergy utilization of UCNPs for brain diseases.

Nanoparticles for super-resolution microscopy: intracellular delivery and molecular targeting

Following an overview of the approaches and techniques used to acheive super-resolution microscopy, this review presents the advantages supplied by nanoparticle based probes for these applications. The various clases of nanoparticles that have been developed toward these goals are then critically described and these discussions are illustrated with a variety of examples from the recent literature.

Recent advances in diverse nanosystems for nitric oxide delivery in cancer therapy

Gas therapy has been proven to be a promising and advantageous treatment option for cancers. Studies have shown that nitric oxide (NO) is one of the smallest structurally significant gas molecules with great potential to suppress cancer. However, there is controversy and concern about its use as it exhibits the opposite physiological effects based on its levels in the tumor. Therefore, the anti-cancer mechanism of NO is the key to cancer treatment, and rationally designed NO delivery systems are crucial to the success of NO biomedical applications. This review summarizes the endogenous production of NO, its physiological mechanisms of action, the application of NO in cancer treatment, and nano-delivery systems for delivering NO donors. Moreover, it briefly reviews challenges in delivering NO from different nanoparticles and the issues associated with its combination treatment strategies. The advantages and challenges of various NO delivery platforms are recapitulated for possible transformation into clinical applications.

Light-activated nanomaterials for tumor immunotherapy

Tumor immunotherapy mainly relies on activating the immune system to achieve antitumor treatment. However, the present tumor immunotherapy used in the clinic showed low treatment efficacy with high systematic toxicity. To overcome the shortcomings of traditional drugs for immunotherapy, a series of antitumor immunotherapies based on nanomaterials have been developed to enhance the body’s antitumor immune response and reduce systematic toxicity. Due to the noninvasiveness, remote controllability, and high temporal and spatial resolution of light, photocontrolled nanomaterials irradiated by excitation light have been widely used in drug delivery and photocontrolled switching. This review aims to highlight recent advances in antitumor immunotherapy based on photocontrolled nanomaterials. We emphasized the advantages of nanocomposites for antitumor immunotherapy and highlighted the latest progress of antitumor immunotherapy based on photoactivated nanomaterials. Finally, the challenges and future prospects of light-activated nanomaterials in antitumor immunity are discussed.

Upconversion Nanomaterials in Bioimaging and Biosensor Applications and Their Biological Response

In recent decades, upconversion nanomaterials (UCNMs) have attracted considerable research interest because of their unique optical properties, such as large anti-Stokes shifts, sharp emissions, non-photobleaching, and long lifetime. These unique properties make them ideal candidates for unified applications in biomedical fields, including drug delivery, bioimaging, biosensing, and photodynamic therapy for specific cancers. This review describes the general mechanisms of upconversion, synthesis methods, and potential applications in biology and their biological responses. Additionally, the biological toxicity of UCNMs is explained and summarized with the associated intracellular association mechanisms. Finally, the prospects and future challenges of UCNMs at the clinical level in biological applications are described, along with a summary of opportunity for biological as well as clinical applications of UCNMs.