Photodynamic Therapy Research Articles

K2FeO4-Enhanced Photodynamic Therapy of Breast Cancer via In Situ Synthesis of Fe2O3 and O2.

Photodynamic Therapy (PDT) offers a promising minimally invasive treatment for breast cancer, but its efficacy is limited by the hostile tumor microenvironment (TME), including hypoxia and high glutathione (GSH) levels. Although various strategies to improve oxygen concentration or reduce reactive oxygen species (ROS) resistance for enhanced PDT have been explored, they typically require intricate design and complex synthesis of multifunctional nanocarriers. Thus, this study introduces a facile K2FeO4-induced strategy to enhance PDT efficiency in breast cancer through the tumor in situ synthesis of Fe2O3 and O2. Inspired by the successful application of K2FeO4 in ecological remediation and hemostasis, K2FeO4 reacts with GSH, biological system, H2O2, and water, to generate Fe2O3 and O2. Intratumoral injection of K2FeO4 improves the TME, followed by Ce6 administration to enhance PDT through synergistic ferroptosis. This approach boosts PDT efficacy significantly by increasing ROS generation, lipid peroxidation, and inhibiting GSH and GPX4. Proteomic analysis revealed alterations in key pathways, including endocytosis and energy metabolism. This K2FeO4-PDT strategy creates a positive feedback loop by enhancing oxidative stress, providing an interesting and promising approach to PDT.

Photodynamic therapy in the treatment of periodontal diseases. Literature review

Periodontal diseases affect about 90% of the adult population, but the treatment regimens for this pathology are different, with varying degrees of effectiveness. One of the causes of inflammatory phenomena is the microbial factor. In some cases, there is a need for antimicrobial prescriptions, which, against the background of growing antibiotic resistance, becomes a problem. This article describes the possibilities of using such a method of influencing periodontal pathogens as photodynamic therapy. The main conclusions of studies on the effectiveness of PDT in inflammatory periodontal diseases are presented.

Preparation of transferrin-modified IR820-loaded liposomes and its effect on photodynamic therapy of breast cancer

ObjectiveTo prepare and characterize transferrin (Tf)-modified liposomes (Lipo) encapsulating the photosensitizing agent neoindocyanine green (IR820), and to investigate their effects on breast cancer 4T1 cells as well as in a breast cancer mouse model.MethodsPhotosensitive liposomes, IR820@Lipo and Tf-IR820@Lipo, were synthesized using thin film dispersion, with encapsulation efficiency assessed via UV detection. The physicochemical properties were analyzed using transmission electron microscopy (TEM) and particle size analysis. Uptake by breast cancer 4T1 cells was evaluated through confocal laser scanning microscopy and flow cytometry, while cell proliferation inhibition was measured using the CCK8 assay. Differences in intracellular fluorescence intensity were utilized to assess drug aggregation in vivo through small animal imaging techniques. The anticancer efficacy and potential side effects of the formulations were examined through pharmacodynamic studies conducted in vivo.ResultsThe mean particle sizes of IR820@Lipo and Tf-IR820@Lipo were found to be 84.30 ± 15.66 nm and 116.20 ± 14.68 nm respectively, with zeta potentials of −8.21 ± 2.06 mV for IR820@Lipo and −5.23 ± 1.19 mV for Tf-IR820@Lipo; TEM revealed that the liposomes exhibited a spheroid morphology with uniform distribution across samples; encapsulation efficiencies reached 86.38 ± 0.99% for IR820@Lipo and an impressive 93.81 ± 1.06% for Tf-IR820@Lipo; notably, Tf-IR820@Lipo significantly inhibited proliferation while promoting apoptosis of the 4T1 cells upon laser irradiation; reactive oxygen species (ROS) detection indicated enhanced fluorescence intensity within the treated cells under light exposure when utilizing both formulations; in vivo experiments demonstrated tumor accumulation of both IR820@Lipo and Tf-IR820@Lipo, indicating effective tumor targeting within a breast cancer mouse model; pharmacodynamic assessments revealed that Tf-IR820@Lipo exhibited superior inhibitory effects against breast cancer without causing liver or kidney dysfunctions in mice nor presenting significant toxic side effects overall.ConclusionGiven its high targeting capability, potent efficacy, and low toxicity profile, Tf-IR820@Lipo holds promise as a novel therapeutic agent for breast cancer treatment when combined with photodynamic therapy (PDT), potentially offering new avenues for patient management.

A case of severe folliculitis decalvans

Folliculitis decalvans is a difficult to treat rare neutrophilic dermatosis that affects the scalp and leads to permanent scarring. The pathogenesis is currently not well understood; the influence of S.aureus antigens, a disorder of the skin microbiome, a defect in cell-mediated immunity, and an imbalance of pro-inflammatory cytokines are assumed. This disease is often associated with a marked decrease in quality of life, because in addition to significant external manifestations, the patient may experience pain, itching and burning in the areas of the rash. The main problem is that there is currently no effective therapy for this disease. Treatment options include systemic antibiotics, topical and intralesional corticosteroids, dapsone, isotretinoin, biologics, and photodynamic therapy. We present a brief overview of the main methods of therapy and a clinical case of a long course of severe folliculitis decalvans, refractory to the main methods of treatment.

Fluorocarbon-Functionalized Polymerization-Induced Self-Assembly Nanoparticles Alleviate Hypoxia to Enhance Sonodynamic Cancer Therapy.

Sonodynamic therapy (SDT) is an ultrasound-based, noninvasive cancer treatment that targets tumor cells by triggering reactive oxygen species production. However, the limited accumulation of sonosensitizers and the insufficient supply of O2 to the hypoxic environment at the tumor site greatly limit the effectiveness of SDT. To address these issues, positively charged porphyrin-containing nanoparticles (NPs) from self-assembling of fluorocarbon/polyethylene glycol amphiphilic block copolymer, which is synthesized through reversible addition-fragmentation chain transfer polymerization, are constructed. The NPs with fluorocarbon core and positively charged hydrophilic shells not only stabilize the sonosensitizer and improve its cellular uptake, but also act as an O2 carrier alleviating the hypoxic tumor environment. In vitro and in vivo experiments demonstrate that the NPs effectively deliver O2 to the tumor and supply sufficient O2 to Renca cells after ultrasound treatment. Consequently, the NPs inhibit hypoxia-induced resistance to SDT and significantly produce reactive oxygen species by activated porphyrin moieties, inducing apoptosis in cancer cells. These oxygen-enhanced sonosensitizer NPs hold promise for cancer therapies such as photodynamic therapy, radiotherapy, and chemotherapy by overcoming hypoxia-induced resistance.

Determination of Photosensitizing Potential of Lapachol for Photodynamic Inactivation of Bacteria

Antimicrobial photodynamic inactivation (aPDI) offers a promising alternative to combat drug-resistant bacteria. This study explores the potential of lapachol, a natural naphthoquinone derived from Tabebuia avellanedae, as a photosensitizer (PS) for aPDI. Lapachol’s photosensitizing properties were evaluated using Staphylococcus aureus and Escherichia coli strains under blue LED light (450 nm). UV-vis spectroscopy confirmed lapachol’s absorption peak at 482 nm, aligning with effective excitation wavelengths for phototherapy. Photoinactivation assays demonstrated significant bacterial growth inhibition, achieving complete eradication of S. aureus at 25 µg·mL−1 under light exposure. Scanning electron microscopy (SEM) revealed morphological damage in irradiated bacterial cells, confirming lapachol’s bactericidal effect. This research underscores lapachol’s potential as a novel photosensitizer in antimicrobial photodynamic therapy, addressing a critical need in combating antibiotic resistance.

Necroptosis as a consequence of photodynamic therapy in tumor cells.

Photodynamic therapy (PDT) is an alternative to cancer treatment, demonstrating selectivity and significant cytotoxicity on malignant tissues. Such therapy involves two nontoxic components: photosensitizer (PS) and non-ionizing radiation. In optimal dosage combinations, PDT causes cellular and tissue effects by oxygen-dependent processes, leading tumor cells to regulated cell death pathways. Regulated necrosis, called necroptosis, can be triggered by PDT and is characterized by caspase-8 inhibition and RIPK1, RIPK3, and MLKL activities, leading to plasma membrane pores formation with subsequent cellular content release into the extracellular space. For this review, studies accessed by PubMed describing the relation between necroptosis and PDT were summarized. The results showed that PDT can trigger necroptosis mechanisms in different tumor cells. Moreover, a mix of different cell death types can co-occur. It is also important to highlight that necroptosis triggered by PDT is related to damage-associated molecular patterns (DAMPs) release, involving immunogenic cell death and vaccination. The cell death response is directly related to the photosensitizer chemical characteristics, concentration, incubation time, cellular location, and irradiation parameters. The synergism among all cell death types is an excellent advantage for avowing tumor resistance mechanisms and developing new solutions.

Synthesis of heavy-atom-free thienoisoindigo dye as near-infrared photosensitizer for type I photodynamic therapy and photoacoustic imaging

Thienoisoindigo (TIIG) has been extensively employed as promising building block of near-infrared (NIR) dyes and organic semiconductor materials. Herein, heavy-atom-free TIIG-based NIR dye TIIGTPA is reported as photosensitizer for combinational photodynamic and photothermal therapy and photoacoustic imaging (PAI). By introducing two methoxy-substituted triphenylamines as the rotors and electron donors at the periphery sites of the electron-deficient TIIG core, dye TIIGTPA featuring Donor-Acceptor-Donor (D-AD) structure is constructed with intensive NIR absorption. Through co-assembly with amphipathic F-127, water-soluble TIIGTPA NPs were prepared with good superoxide anion radical (O2-•) production and high photothermal conversion efficiency (PCE) of 59.0 % under 730 nm photoirradiation. Additionally, the excellent photothermal effect enabled a superior photoacoustic response for tumor blood vessel visualization through PAI. All results indicated the favorable potential of TIIGTPA NPs for PAI-mediated combinational phototherapy.

Cyclodextrin-activated porphyrin-DNA nanofibers with AS1411/Hemin toehold for enhanced and targeted photodynamic therapy

Targeted photodynamic therapy is considered superior to conventional photodynamic therapy due to the enhanced uptake of photosensitizers by tumor cells. However, porphyrin-based photodynamic therapy is still limited due to the low hydrophilicity, poor biocompatibility and susceptibility to quenching of photosensitizers. Herein, we report cyclodextrin-activated porphyrin-DNA nanofibers with AS1411/Hemin toeholds, which enable targeted cancer cells recognition and catalytic oxygenation for enhanced photodynamic therapy. The nanofibers are formed through the self-assembly of the host–guest complex of cyclodextrin and porphyrin-DNA amphiphiles, and can be further functionalized on the surface with AS1411/Hemin. AS1411/Hemin can specifically target nucleolin-overexpressing cancer cells and catalyze conversion of excessive H2O2 into O2 within tumor cells, thereby alleviating tumor hypoxia and further cascaded enhancing PDT efficacy. These results suggest that the programmable and multifunctional nanofiber provided an effective nanoplatform for enhanced and targeted photodynamic therapy.

A straightforward strategy to modulate ROS generation of AIE photosensitizers for type-I PDT

Type-I photodynamic therapy (PDT), valued for its reduced oxygen requirement, generates highly cytotoxic •OH radicals. However, conventional strategies for developing type-I photosensitizers (PSs) are complex and involve intricate organic synthesis. Herein, we present a novel strategy to alter the generation of reactive oxygen species (ROS) by simply manipulating the twisting degree of donor–acceptor (D−A) type aggregation-induced emission (AIE) PSs. Specifically, natural saturated fatty acids are employed to modulate the twisting state of AIE PSs, with higher doping ratios yielding more twisted structures and increased type-I ROS generation. In contrast, fatty acids with higher crystallinity promote planar structures and type-II ROS generation. Theoretical calculations suggest that AIE PSs with highly twisted structures lead to a prominent reduction in ΔEST and effective separation of electron−hole pairs, thereby favoring efficient intersystem crossing and charge transfer. The PDT system primarily driven by type-I ROS exhibits efficient bactericidal activity against clinically drug-resistant bacteria, which remarkably accelerates the recovery of bacteria-infected wounds in mice. This study demonstrates the first example of modulating ROS generation type by manipulating the twisting degree of D−A type AIE PSs, eliminating the need for intricate molecular design and organic synthesis. The proposed strategy opens up new avenues for advancing PDT applications.

In situ endoscopic photodynamic therapy combined with immature DC vaccination induces a robust T cell response against peritoneal carcinomatosis.

Immunogenic cell death (ICD) and ferroptosis have recently emerged as key factors in the anticancer immune response. Among the treatments able to induce ICD and the associated release of danger signals is photodynamic therapy (PDT). Ferroptosis for its part results from lipid peroxidation and is induced by CD8+ T cells to kill nearby cancer cells on IFN-γ production. We aimed to combine the two concepts, that is, to evaluate whether the strong pro-oxidant effects of PDT may promote ferroptosis and antigen release and to develop a procedure for in situ PDT to prepare the soil for highly endocytotic immature dendritic cell (iDC) adoptive transfer. This approach was implemented for managing peritoneal carcinomatosis, a lesion often associated with poor outcomes. We used three-dimensional (3D) heterotypic spheroids made of cancer cells, exposed them to a white light-activated OR141 photosensitizer (PS), and subsequently complexified them by adding iDC and naive lymphocytes. We next used a model of mouse peritoneal carcinomatosis and administered PDT using laparoscopy to locally induce photoactivation using the endoscope light. The immune response following adoptive transfer of iDC was tracked both in vivo and ex vivo using isolated immune cells from in situ vaccinated mice. Cancer cells undergoing PDT-induced cell death significantly increased ICD markers and the infiltration of iDCs in spheroids, relying on ferroptosis. These actions induced the sequential activation of CD8+ and CD4+ T cells as revealed by a significant spheroid 3D structure deterioration and, remarkably, were not recapitulated by conventional ferroptosis inducer RSL3. Using LED light from an endoscope for in situ photoactivation of PS enabled us to apply the vaccination modality in mice with peritoneal tumors. Consecutive intraperitoneal injection of iDCs resulted in delayed tumor growth, increased survival rates, and prevented tumor relapse on rechallenge. CD8+ T cell response was supported by depletion experiments, nodal detection of early activated T cells, and ex vivo T cell-induced cytotoxicity toward spheroids. The combination of in situ PDT locally delivered by an endoscope light and iDC administration induces a durable memory immune response against peritoneal carcinomatosis thereby opening new perspectives for the treatment of a life-threatening condition.

Overcoming therapeutic limitations in glioblastoma treatment: A nanocomposite inducing ferroptosis and oxeiptosis via Photodynamic therapy

Photodynamic therapy (PDT) is an effective treatment for glioblastoma (GBM) that activates photosensitizers to produce reactive oxygen species (ROS) while minimizing harm to normal tissues.However, the therapeutic outcomes of PDT are often unsatisfactory. This limitation arises partly from the challenges posed by the blood–brain barrier (BBB) in transporting photosensitizers and partly from the excessive levels of glutathione (GSH) in the tumor microenvironment (TME), which can neutralize ROS. Hypericin (HYP) has emerged as a promising photosensitizer for PDT due to its excellent photosensitizing properties and antitumor activity. Dysregulated iron metabolism is a hallmark of numerous cancers, including GBM. In this study, biodegradable tetra-sulfide-bound dendritic mesoporous organosilicas nanocomposite (NCs) modified with bovine serum albumin (BSA) were synthesized. NCs penetrates the BBB and selectively targets GBM by binding to secreted acidic protein acidic and rich in cysteine (SPARC), an albumin-binding receptor that is prominently expressed in both the BBB and GBM. Upon degradation in response to high GSH concentrations in the TME, the NCs release their payload while concurrently depleting GSH. Under laser irradiation, the ROS-generating agent HYP, loaded within the NCs, is combined with the ferroptosis inducer erastin to achieve a synergistic anti-GBM effect via PDT/ferroptosis. Additionally, the NCs induces oxeiptosis by regulating KEAP1/PGAM5/AIFM1 pathway. Consequently, NC inhibits GBM growth by inducing ferroptosis and oxeiptosis through excessive ROS production. This study demonstrates the potential of NCs to enhance the effectiveness of PDT, offering a promising therapeutic strategy for GBM patients.

Chitosan-naphthalimide probes for dual channel recognition of HClO and H2S in cells and their application in photodynamic therapy

The combination of bio-imaging with photodynamic therapy (PDT) to accomplish theranostics is promising in cancer treatment. Three chitosan-naphthalimide probes were studied in this work. 4-(5-Bromothiophen-2-yl)-1,8-naphthalic anhydride was first synthesized, and then reacted with chitosan to obtain the macromolecules (CS-N-Br). The recognition group thiomorpholine or its derivatives were introduced into CS-N-Br to obtain nano-probes (CS-N-ML, CS-N-BSZ, CS-N-FSQ) eventually. The studies revealed that CS-N-ML and CS-N-FSQ exhibit high selectivity and can specifically recognize HClO and H2S. CS-N-ML and CS-N-FSQ can perform exogenous and endogenous confocal imaging of HClO and H2S in cells also. CS-N-ML's ability to target lysosomes positions indicated it could act as a lysosome-specific probe. It was discovered that the probes generate superoxide anions (O2•−) via a Type I mechanism. This discovery endows the probes with high photosensitizing activity even under hypoxic conditions. There is a positive correlation between the extent of the conjugated system and the photosensitivity of the probes, indicating that an enhanced conjugation leads to increased photosensitivity. Upon light irradiation, the probes generate ROS within HeLa cells. These results suggested that these probes can achieve theranostics for diseases associated with abnormal levels of HClO and H2S.

Disseminated Superficial Actinic Porokeratosis: A Systematic Treatment Review.

Disseminated superficial actinic porokeratosis (DSAP) is a disorder of keratinization characterised by small, brown plaques with elevated keratotic rims, typically occurring on sun exposed areas. DSAP poses a risk for malignant transformation, emphasising the need for effective management strategies. The aim of this study was to review the current reported management options for DSAP. This systematic review was based on a comprehensive search of databases (Cochrane, PubMed, Medline, Embase, Emcare, ProQuest, Web of Science, CINAHL) from inception to 15 March 2024. Studies reporting management of DSAP were included irrespective of study design. Of 923 citations, 61 studies were included, predominantly comprising case reports and retrospective case series. A limited number of randomized and open-label trials were identified. Various treatment modalities were reported, including topical and systemic agents, photodynamic therapy, and laser therapy. Multiple management options are available for DSAP, including topical and systemic agents, photodynamic therapy and laser treatments. However, these approaches vary in their balance between efficacy and toxicity. Currently, there is a paucity of high-quality clinical trial data to guide treatment decisions. Further studies are required to determine the most effective and safe management strategies for DSAP. PROSPEROREGISTRATION: CRD42024514558.

Advancing Photodynamic Therapy with Nano-Conjugated Hypocrellin: Mechanisms and Clinical Applications.

Hypocrellin-based photodynamic therapy (PDT) is developing as a viable cancer therapeutic option, especially when enhanced by nanoconjugation. This review investigates the methods by which nano-conjugated hypocrellin enhances therapeutic efficacy and precision when targeting cancer cells. These nanoconjugates encapsulate or covalently bind hypocrellin photosensitizers (PSs), allowing them to accumulate preferentially in malignancies. When activated by light, the nanoconjugates produce singlet oxygen and other reactive oxygen species (ROS), resulting in oxidative stress that selectively destroys cancer cells while protecting healthy tissues. We look at how they can be used to treat a variety of cancers. Clinical and preclinical studies show that they have advantages such as increased water solubility, improved tumor penetration, longer circulation times, and tailored delivery, all of which contribute to fewer off-target effects and overall toxicity. Ongoing research focuses on improving these nanoconjugates for better tumor targeting, drug release kinetics, and overcoming biological obstacles. Furthermore, the incorporation of developing technologies such as stimuli-responsive nanocarriers and combination therapies opens exciting opportunities for enhancing hypocrellin-based PDT. In conclusion, the combination of hypocrellin and nanotechnology constitutes a significant approach to cancer treatment, increasing the efficacy and safety of PDT. Future research will seek to create conjugates including hypocrellin, herceptin, and gold nanoparticles to induce apoptosis in human breast cancer cells in vitro, opening possibilities for therapeutic applications.

“Balloon-like” biomimetic erythrocyte vesicles potentiate photodynamic therapy for inducing immunogenic cell death

Photodynamic therapy (PDT) for cancer is known for its minimal invasiveness and safe characteristics, but the hypoxic tumor microenvironment still limits efficacy. Herein, we have developed a novel “balloon-like” biomimetic erythrocyte vesicle, which is constructed by loading chlorin e6 (Ce6) and oxygenated hemoglobin (Hb) in a folate (FA)-modified, PEGylated liposome, denoted as Ce6-Hb-FA@lip (CHFL). The CHFL exhibits high biocompatibility and good stability in PBS solution. Moreover, CHFL possesses the “balloon-like” elastic structure for oxygen binding with the change of volume. Both in vitro and in vivo studies demonstrate an effective PDT of CHFL, which significantly reverses the hypoxic microenvironment of tumor cells through the targeted cotransmission of Ce6 and Hb. Additionally, this biomimetic erythrocyte vesicle can induce oxidative stress to enhance tumor immunogenicity and trigger immunogenic cell death (ICD). Thus, the dying tumor cells can activate both dendritic cells (DCs) and T lymphocytes, which, in turn, initiates the antitumor immune response by releasing the damage-associated molecular patterns (DAMPs). This effective and safe platform holds great promise in the development of nanomedicines for innovative oxygen-enhanced PDT in the treatment of cancer.

Designing Quasi-Intrinsic Photosensitizers with Dual Function of Fluorescence Imaging and Photodynamic Therapy.

Photosensitizers (PSs) with effective two-photon absorption in the therapeutic window are the key to two-photon photodynamic therapy. However, the traditional exogenous PSs usually lead to rejection in the body. Besides, the precise visualization of treatments proposes new demands and challenges for the design of PSs. Accordingly, in this work, a series of quasi-intrinsic PSs are obtained based on the artificial base 2-amino-8-(1'-β-d-2'-deoxyribofuranosyl)-imidazo[1,2-α]-1,3,5-triazin-4(8H)-one (P). The calculations show that the structural modification could enhance the two-photon absorption and fluorescence emission, which is beneficial for tumor localization. Furthermore, the reduced singlet-triplet energy gaps and enhanced spin-orbit coupling contribute to the rapid intersystem crossing process, which results in a triplet state with high quantum yields. To ensure the phototherapeutic performance of the newly designed PSs, we also examined the vertical electron affinity and vertical ionization potential for generation of superoxide anions, as well as the T1 energy required to produce singlet oxygen.

An injectable dual-layer chitosan-alginate nano-hydrogel incorporated Cu(I)-isopolymolybdate-based metal-organic framework tailored for three-in-one anti-cancer nanotherapy

Designing potential agents and constructing hydrophilic nano-hydrogel platforms for biomedical and pharmaceutical applications, especially for polyoxometalate-based metal-organic frameworks (PMOF), present both great desirability and significant challenges. A unique open porous Cu(I)-isopolymolybdate-based metal-organic framework (CCUT) has been self-assembled through ionothermal processes for in vivo synergistic anti-cancer therapy. The periodicity of Drugs@CCUT-1 (nano-crystals of CCUT after cation exchange and anti-cancer drugs upload) has been investigated by synchrotron wide-angle X-ray scattering, confirming the lattice structure unchanged. To mitigate toxicity, enhance stimuli-responsive drug delivery, hydrophilicity, and biocompatibility, an injectable dual-layer chitosan//alginate-based nano-hydrogel is developed to incorporate Drugs@CCUT-1. Potential interactions between the chitosan layer and the surface of CCUT-1 have been analyzed by Density Functional Theory (DFT). Furthermore, the nanoparticles Drugs@CCUT-1@Gel exhibit efficient type I photodynamic therapy (PDT) and chemodynamic therapy (CDT) within the bio-window, effectively eradicating tumors in deep tissue. CCUT-1 generates a substantial amount of reactive oxygen species (ROS), stimulating the Keap1-Nrf2 signaling pathway and resulting in the expression of phase II enzymes, typically HO-1. CCUT-1@Gel not only demonstrates high capacity for anti-cancer drug upload and release, but also exhibits strong synergistic CDT/PDT in vivo anti-tumor efficacy. Hence, CCUT-1@Gel represents a promising in vivo nano-platform for synergistic chemotherapy (CT)/CDT/PDT three-in-one anti-cancer approach.

Hyaluronic acid-functionalized MOFs for combined sunitinib and siRNA therapy in renal cell carcinoma

Sunitinib is a first-line treatment for renal cell carcinoma (RCC), but suffers from drug resistance, causing therapy failure. Therefore, nano-scale delivery systems should be introduced for targeted delivery. Metal-organic frameworks (MOFs) are attractive drug carriers that not only enable multidrug combination therapies but also exert photodynamic effects by incorporating photosensitizers as components. Here, a Zr-based porphyrinic nanoscale MOF, PCN224, was prepared as the carrier for the co-delivery of sunitinib and the siRNA against vascular endothelial growth factor receptor-2 (VEGFR-2). Drug-loaded PCN-224 is coated with hyaluronic acid (HA) to prevent drug molecular leakage and to exert tumor-targeting effects (CD44 in tumor cells). Photodynamic therapy was conducted under 660 nm laser (50 mW·cm−2, 10 min) irradiation. Compared with St/siVEGFR-2@PCN-224@HA without the HA coating, St/siVEGFR-2@PCN-224@HA significantly suppressed cell viability and promoted cell apoptosis. Laser irradiation further increased the anti-cancer effect of St/siVEGFR-2@PCN-224@HA by generating cytotoxic ROS. H&E staining of major organs revealed no signs of damage, indicating the biosafety of St/siVEGFR-2@PCN-224@HA. The prepared St/siVEGFR-2@PCN-224@HA system enables triple inhibition of tumor growth via a combination of targeted therapy and genetic and photodynamic therapy to enhance the therapeutic effects on RCC.

Applications Of Photodynamic Therapy In Periodontal Diseases

Background: According to A. Marcacci et al (1888), when many reports emerged on light absorbing properties and of fluorescence of various dyes, it became clear that dye excitation by light exerts destructive action in biological systems. This so-called photodynamic action was described as a process in which light, after being absorbed by dyes sensitizes organisms for visible light inducing cell damage. The supra- and subgingival plaque biofilm on tooth surfaces should easily be accessible for flushing with the dye and for activating them by light. Thus, periodontal diseases are promising applications of Photodynamic Therapy. Introduction: Chronic periodontitis is the most common periodontal disease which is related to the chronic accumulation of bacterial plaque. Since mechanical methods are not sufficient in the treatment of this disease, administration of local/systemic antibiotic is recommended following mechanical debridement. However, side effects of antibiotics such as microbial resistance and patient allergy led to development of alternative methods. One of these suggested methods is the antimicrobial photodynamic therapy (aPDT). PDT is a local noninvasive treatment modality without the side effects caused by antibiotics. Objectives: In this review, the mechanism of action of PDT and its application in the treatment of various periodontal conditions along with its future trends are discussed. Conclusion: Even though PDT is still in experimental stages of development and testing, the method may be an adjunct to conventional antibacterial measures in periodontology and Implant related perspectives.