Multifunctional photodynamic/photothermal nano-agents for the treatment of oral leukoplakia

Advancing oral cancer care: nanomaterial-driven diagnostic and therapeutic innovations

The advent of nanotechnology has significantly advanced the diagnosis and treatment of oral cancer, offering more precise and efficient therapeutic strategies. This review presents a comprehensive overview of recent developments in the application of nanotechnology to oral cancer management. It begins with an overview of the epidemiology of oral cancer and outlines current diagnostic and therapeutic methods. The classification and advantages of various nanomaterials are then introduced. The paper thoroughly explores the use of nanomaterials as drug delivery systems (DDSs), imaging contrast agents, and therapeutic tools, with particular emphasis on multifunctional nanoplatforms that integrate diagnostics and therapy. These platforms enable real-time monitoring and immediate therapeutic response, offering innovative approaches for early detection and intervention. Despite these promising advances, several challenges persist, including issues related to biocompatibility, clearance, targeting specificity, and clinical translation. The review concludes by highlighting current limitations and proposing future directions for the clinical application of nanotechnology in oral cancer treatment.

Advances in Photothermal Therapy for Oral Cancer

Oral cancer represents a critical global health issue, where traditional treatment modalities are often characterized by considerable adverse effects and suboptimal effectiveness. Photothermal therapy (PTT) offers an innovative method for tumor treatment, leveraging photothermal agents to convert light into hyperthermia, ultimately leading to tumor ablation. PTT offers unique advantages in treating oral cancer due to its superficial anatomical location and consequent accessibility to laser irradiation. PTT's advantage is further enhanced by its capacity to facilitate drug release and promote tissue regeneration. Consequently, the application of PTT for oral cancer has garnered widespread interest and has undergone rapid development. This review outlines advances in PTT for oral cancer, emphasizing strategies to improve efficacy and combination therapy approaches. The key challenges, including temperature control and long-term biosafety, are discussed alongside future directions. The review also encompasses PTT's role in managing oral potentially malignant disorders and postoperative defects, conditions intimately linked with oral cancer. We aim to provide guidance for emerging PTT research in oral cancer and to promote the development of precise and efficient treatment strategies.

Hyaluronic acid-functionalized supramolecular nanophotosensitizers for targeted photoimmunotherapy of triple-negative breast cancer

Triple-negative breast cancer (TNBC) is recognized as a particularly aggressive subtype of breast cancer that is devoid of effective therapeutic targets. Immune checkpoint inhibitors (ICIs) have demonstrated promising results in TNBC treatment. Nonetheless, most patients either develop resistance to ICIs or fail to respond to them initially. Owing to its spatio-temporal precision and non-invasive nature, photoimmunotherapy offers a targeted therapeutic strategy for TNBC. Herein, we report hyaluronic acid (HA)-functionalized indocyanine green-based supramolecular nanoparticles (HGI NPs), with biodegradable characteristics, for high-performance photoacoustic imaging and targeted phototherapy for TNBC. Notably, HGI NPs can significantly gather in TNBC tissues because of the enhanced permeability and retention effect of the tumor, and the tumor-targeting properties of HA. The strong amplification of HGI nanoparticles triggers a significant immunogenic cell death (ICD) response when exposed to 808 nm light, thus shifting the immunosuppressive tumor microenvironment (iTME) into a tumor attack mode and 'hot' state. Antitumor experiments demonstrate the high efficiency of the supramolecular photosensitizers HGI NPs for TNBC elimination and good biosafety. This synergistic strategy reshapes the iTME and amplifies the antitumor immune response, providing a theoretical foundation for combining phototherapy and ICIs as potential treatments for TNBC.

Emerging nanozyme therapy incorporated into dental materials for diverse oral pathologies

OBJECTIVE

Nanozyme materials combine the advantages of natural enzymes and artificial catalysis, and have been widely applied in new technologies for dental materials and oral disease treatment. Based on the role of reactive oxygen species (ROS) and oxidative stress pathways in the occurrence and therapy of oral diseases, a comprehensive review was conducted on the methods and mechanisms of nanozymes and their dental materials in treating different oral diseases.

METHODS

This review is based on literature surveys from PubMed and Web of Science databases, as well as reviews of relevant researches and publications on nanozymes in the therapy of oral diseases and oral tumors in international peer-reviewed journals.

RESULTS

Given the unique function of nanozymes in the generation and elimination of ROS, they play an important role in the occurrence, development, and treatment of different oral diseases. The application of nanozymes in dental materials and oral disease treatment was introduced, including the latest advances in their use for dental caries, pulpitis, jaw osteomyelitis, periodontitis, oral mucosal diseases, temporomandibular joint disorders, and oral tumors. Future approaches were also summarized and proposed based on the characteristics of these diseases.

SIGNIFICANCE

This review will guide biomedical researchers and oral clinicians to understand the mechanisms and applications of nanozymes in the therapy of oral diseases, promoting further development in the field of dental materials within the oral medication. It is anticipated that more suitable therapeutic agents or dental materials encapsulating nanozymes, specifically designed for the oral environment and simpler for clinical utilization, will emerge in the forthcoming future.

Oxidative stress promotes oral carcinogenesis via Thbs1-mediated M1-like tumor-associated macrophages polarization

Although oxidative stress is closely associated with tumor invasion and metastasis, its' exact role and mechanism in the initial stage of oral cancer remain ambiguous. Glutamine uptake mediated by alanine-serine-cysteine transporter 2 (ASCT2) participates in glutathione synthesis to resolve oxidative stress. Currently, we firstly found that ASCT2 deletion caused oxidative stress in oral mucosa and promoted oral carcinogenesis induced by 4-Nitroquinoline-1-oxide (4-NQO) using transgenic mice of ASCT2 knockout in oral epithelium. Subsequently, we identified an upregulated gene Thbs1 linked to macrophage infiltration by mRNA sequencing and immunohistochemistry. Importantly, multiplex immunohistochemistry showed M1-like tumor-associated macrophages (TAMs) were enriched in cancerous area. Mechanically, targeted ASCT2 effectively curbed glutamine uptake and caused intracellular reactive oxygen species (ROS) accumulation, which upregulated Thbs1 in oral keratinocytes and then activated p38, Akt and SAPK/JNK signaling to polarize M1-like TAMs via exosome-transferred pathway. Moreover, we demonstrated M1-like TAMs promoted malignant progression of oral squamous cell carcinoma (OSCC) both in vitro and in vivo by a DOK transformed cell line induced by 4-NQO. All these results establish that oxidative stress triggered by ASCT2 deletion promotes oral carcinogenesis through Thbs1-mediated M1 polarization, and indicate that restore redox homeostasis is a new approach to prevent malignant progression of oral potentially malignant disorders.

Potential of photodynamic therapy as a minimally invasive treatment for oral verrucous carcinoma

Oral verrucous carcinoma (OVC) and proliferative verrucous leukoplakia (PVL) share similar histological characteristics and may have a common origin. When they appear simultaneously, the risk of malignant transformation in PVL increases. In elderly patients with both conditions, a safe, effective, simple, and minimally invasive treatment is preferable. Photodynamic therapy (PDT), a non-invasive treatment, utilizes specific wavelengths of light to activate photosensitizers, generating reactive oxygen species that selectively target malignant tissues with cytotoxic effects. This case report describes an elderly patient with coexisting extensive leukoplakia, PVL, and OVC, who achieved complete remission with no recurrence at 10 months following PDT. The treatment resulted in a satisfactory clinical outcome, preserving both the appearance and function of the oral cavity.

Oxygen vacancy formation strengthened microwave catalysis of Zn-Zr solid solution for antibiotic-free therapy strategies of bacteria-infected osteomyelitis

Osteomyelitis, a grave deep tissue infection primarily caused by Staphylococcus aureus, results in serious complications such as abscesses and sepsis. With the incidence from open fractures exceeding 30 % and prevalent antibiotic resistance due to extensive treatment regimens, there's an urgent need for innovative, antibiotic-free strategies. Photothermal therapy (PTT) and photodynamic therapy (PDT) renowned for generating localized reactive oxygen species (ROS), face limitations in penetration depth. To overcome this, our method combines the deep penetration attributes of medical microwaves (MW) with the synergistic effects of the ZnO/ZrO2 solid solution. Comprehensive in vitro and in vivo evaluations showcased the solid-solution's potent antibacterial efficacy and biocompatibility. The ZnO/ZrO2 solid solution, especially in a 7:3 M ratio, manifests superior microstructural characteristics, optimizing MW-assisted therapy. Our findings highlight the potential of this integrated strategy as a promising avenue in osteomyelitis management.

Efficacy of Aminolevulinic Acid Mediated Photodynamic Therapy in the Treatment of Oral Premalignant Lesions: A Systematic Review

BACKGROUND

Aminolevulinic acid (ALA) mediated photodynamic therapy (PDT) is considered as an effective treatment option for oral premalignant lesions. ALA is a Food and Drug Administration (FDA) approved second-generation photosensitizer (PS) used both orally as well as topically.

OBJECTIVE

This systematic review aims to evaluate the efficacy of ALA-PDT for the treatment of oral premalignant lesions.

METHODS

The focused question was, "Is ALA-PDT effective in the treatment of oral premalignant lesions?"A literature search was made in PubMed/Medline and GoogleScholar using different combinations of the following keywords: photodynamic therapy, oral premalignant lesions, oral leukoplakia (OL), erythroplakia, oral erythroleukoplakia (OEL), oral verrucous hyperplasia (OVH); and oral lichen planus (OLP). Review articles, preclinical studies, case-reports, commentaries, letters to the Editor, unpublished articles, studies on photodynamic therapy used in areas other than the oral cavityand, articles published in languages other than English were excluded. The relevant information was summarized.

RESULTS

There were initially 64 results for the above parameters; 47 studies were excluded, leaving 17 studies for analysis. Characteristics of the included studies, PS, and PDT protocol were summarized.

CONCLUSION

The outcome of the included studies suggested that ALA-PDT is an effective, easy to perform technique, well tolerated treatment with encouraging achievements in the treatment of oral premalignant lesions. No systemic side effects and skin photosensitivity were reported with topical ALA even within initial 48 hours after PDT, and patients were not required to avoid exposure to light following treatment. The clinical outcome of the ALA-PDT application, as reported in the studies, was also very promising, with either diminution in the size of the lesion or complete remission or improvement in signs and symptoms as well as reduced recurrence.

Carrier-Free Self-Assembled Nanomedicines for Promoting Apoptosis and Inhibiting Proliferation in Hepatocellular Carcinoma

In order to improve the effectiveness of tumor treatment and reduce the toxic side effects of drugs, we formed carrier-free multifunctional nanoparticles (BI NPs) by noncovalent interaction of berberine hydrochloride and IR780. BI NPs possessed the synergistic effects of promoting apoptosis, inhibiting proliferation and metastasis of tumors, and phototherapeutic treatment. Dispersive and passive targeting ability retention (EPR) effects of BI NPs on tumor sites in vivo could be monitored by fluorescence imaging. In addition, BI NPs exhibited effective reactive oxygen species (ROS) generation and photothermal conversion capabilities, photodynamic therapy (PDT), and photothermal therapy (PTT). Importantly, BI NPs inhibit tumor suppression through the AMPK/PI3K/AKT signaling pathway to inhibit tumor proliferation and metastasis. BI NPs not only have efficient in vivo multimodal therapeutic effects but also have good biosafety and potential clinical applications.

Clinical efficacy of photodynamic therapy of oral potentially malignant disorder

OBJECTIVE

To investigate the clinical efficacy of aminovalerate hydrochloride photodynamic therapy (PDT) for oral potentially malignant disorder (OPMD),oral leukoplakia (OLK), along with identifying the influencing factors.Additionally, the study aims to detect the rates of recurrence and malignancy after PDT.

METHOD

60 patients with OPMD who received PDT at our hospital from 2006 to 2021 were included in this study. Relevant patient medical data were collected and analyzed using SAS 9.4 software.The Mann-Whitney U test was used to retrospectively analyze the factors influencing clinical efficacy, as well as recurrence rate and malignant transformation rate (MTR) after treatment.

RESULT

Among the 60 OPMD patients receiving PDT, complete remission in 13 (21.67 %), partial remission in 39 (65.00 %), and no remission in eight (13.33 %), resulting in an overall effective rate of 86.67 %.Fifteen patients experienced relapse, leading to a recurrence rate of 25.00 %. Among these relapses,11 patients occurred within one year after treatment, corresponding to an 18.33 % recurrence rate during that period. Moreover, nine patients developed malignant transformation (MT), resulting in an MTR of 15.00 %. Out of these patients, six individuals developed MT within one year after treatment, resulting in a one-year MTR of 10.00 %.

CONCLUSION

The study findings indicate that PDT shows promising clinical efficacy in the treatment of OPMD, with relatively limited and tolerable postoperative adverse reactions. However, there remains a certain rate of recurrence and malignancy after treatment. Therefore, close attention should be paid to postoperative monitoring, regular follow-up, and further expansion of the sample size to observe its long-term efficacy.

Clinical evaluation of photodynamic therapy for oral leukoplakia: a retrospective study of 50 patients

BACKGROUND

Topical photodynamic therapy (PDT) has demonstrated encouraging results in the treatment of oral leukoplakia (OLK). However, data on the clinical efficacy of PDT in Chinese patients with OLK are still limited.

METHODS

Fifty patients diagnosed with OLK were enrolled, including patients with various dysplastic tissues. All patients received topical PDT with 5-aminolevulinic acid (5-ALA) as a photosensitizer. Clinical efficacy was evaluated 4 weeks after treatment. Follow-up was performed every 3 months during the first year and every 6 months during the second year.

RESULTS

The overall response rate was 68% (34/50): 12% (n = 6) complete and 56% (n = 28) partial responses. Aneuploidy was reduced in the patients with dysplastic lesions. Oral pain and local ulcers developed in 52% of the patients (n = 26). Patients with a long history of OLK including hyperplasia and dysplastic lesions, as well as those with non-homogenous lesions, were more likely to develop pain and ulcer. During follow-up, the recurrence rate of hyperplasia and dysplastic lesions was 32% (n = 16) and the malignant transformation rate of dysplastic lesions was 4% (n = 2). Lesions on the buccal mucosa were associated with recurrence (P = 0.044; OR: 0.108, 95% CI: 0.013-0.915).

CONCLUSION

Topical 5-ALA-mediated PDT is an effective treatment for OLK, particularly for homogenous leukoplakia, with few side effects. The buccal mucosa may be a protective factor that can reduce recurrence.

Nano-drug delivery system targeting FAP for the combined treatment of oral leukoplakia

Oral leukoplakia (OLK) has received much attention due to its potential risk of malignant transformation. Studies have shown that when drug therapy is combined with photothermal therapy (PTT), not only can the cytotoxicity of the drug be enhanced, but also the heat energy can be used to kill the lesion cells, so we can combine drug therapy with PTT to enhance the therapeutic effect on OLK. However, with certain drawbacks due to its lack of targeting, fibroblast activating protein (FAP) has become an attractive target for OLK combination therapy. In this study, we used NGO-PEG loaded with FAP-targeting peptide (F-TP) and celecoxib (CXB) to construct a nano-drug delivery system CGPF for targeting OLK with high FAP expression and confirmed the biocompatibility and therapeutic efficacy of CGPF by in vitro and in vivo experiments. Overall, the novel nano-drug delivery system CGPF proposed in this study showed a very significant potential for the combination therapy of OLK.

Photodynamic therapy empowered by nanotechnology for oral and dental science: Progress and perspectives

Photodynamic therapy (PDT), as a noninvasive therapeutic modality, has significantly revolutionized the contemporary management of oral and dental health. Recently, PDT has witnessed significant technological advancements, especially with the introduction of biomaterials and nanotechnologies, thus highlighting its potential as a multi-functional tool in therapeutics. In this review, our objective was to provide a comprehensive overview of the advancements in nanotechnology-enhanced PDT for the treatment of oral diseases, encompassing dental caries, root canal infection, periodontal disease, peri-implant inflammation, tooth staining, and whitening, as well as precancerous lesions and tumors. Furthermore, we extensively deliberated upon the persisting challenges and prospective avenues of nanotechnology-enhanced PDT in the realm of oral diseases, which will open up new possibilities for the application of nanotechnology-enhanced PDT in clinical implementation.

A self-stabilized and water-responsive deliverable coenzyme-based polymer binary elastomer adhesive patch for treating oral ulcer

Oral ulcer can be treated with diverse biomaterials loading drugs or cytokines. However, most patients do not benefit from these materials because of poor adhesion, short-time retention in oral cavity and low drug therapeutic efficacy. Here we report a self-stabilized and water-responsive deliverable coenzyme salt polymer poly(sodium α-lipoate) (PolyLA-Na)/coenzyme polymer poly(α-lipoic acid) (PolyLA) binary synergistic elastomer adhesive patch, where hydrogen bonding cross-links between PolyLA and PolyLA-Na prevents PolyLA depolymerization and slow down the dissociation of PolyLA-Na, thus allowing water-responsive sustainable delivery of bioactive LA-based small molecules and durable adhesion to oral mucosal wound due to the adhesive action of PolyLA. In the model of mice and mini-pig oral ulcer, the adhesive patch accelerates the healing of the ulcer by regulating the damaged tissue inflammatory environment, maintaining the stability of oral microbiota, and promoting faster re-epithelialization and angiogenesis. This binary synergistic patch provided a therapeutic strategy to treat oral ulcer.

Developmental synergism in the management of oral potentially malignant disorders

Oral potentially malignant disorders (OPMDs) are associated with an increased risk of occurrence of cancers of the oral cavity or lips. The unifying theme of OPMDs is their potential risk for cancer development. Therefore, the primary objective of the management should be to prevent carcinogenesis. Beyond diagnosis, current strategies for the management of OPMDs predominantly include non-surgical and surgical interventions and a "watch-and-see" approach, such as disease monitoring or surveillance, and preventive strategies. Though no optimal clinical treatment has gained universal approval for reducing or preventing malignant development of OPMDs. Therefore, an urgent need exits for improved treatment properties and effective predictive markers for OPMDs treatment. This review aims to outline recent synergism regarding to the management of OPMDs. Developing new technologies and improved application parameters to promote the treatment efficacy and a novel management prescription approach to OPMDs are proposed.

Nanomaterials-mediated photodynamic therapy and its applications in treating oral diseases

Oral diseases, such as dental caries, periodontitis and oral cancer, have a very high morbidity over the world. Basically, many oral diseases are commonly related to bacterial infections or cell malignant proliferation, and usually located on the superficial positions. These features allow the convenient and efficient application of photodynamic therapy (PDT) for oral diseases, since PDT is ideally suitable for the diseases on superficial sites and has been widely used for antimicrobial and anticancer therapy. Photosensitizers (PSs) are an essential element in PDT, which induce the generation of a large number of reactive oxygen species (ROS) upon absorption of specific lights. Almost all the PSs are small molecules and commonly suffered from various problems in the PDT environment, such as low solubility and poor stability. Recently, reports on the nanomedicine-based PDT have been well documented. Various functionalized nanomaterials can serve either as the PSs carriers or the direct PSs, thus enhancing the PDT efficacy. Herein, we aim to provide a comprehensive understanding of the features of different oral diseases and discuss the potential applications of nanomedicine-based PDT in the treatment of some common oral diseases. Also, the concerns and possible solutions for nanomaterials-mediated PDT are discussed.