Photodynamic therapy of lung cancer with photosensitizers based on polycationic derivatives of synthetic bacteriochlorin (experimental study).

BACKGROUND: One of the tasks of anticancer photodynamic therapy is increasing the efficacy of treatment of cancer nodes with large (clinically relevant) sizes using near-infrared photosensitizers (PS). METHODS: The anticancer efficacy and mechanisms of the photodynamic action of PS based on polycationic derivatives of synthetic bacteriochlorin against Lewis lung carcinoma were studied in vitro and in vivo. RESULTS: It was found that studied PS have high phototoxicity against Lewis lung carcinoma cells: the IC50 values were about 0.8 µM for tetracationic PS and 0.5 µM for octacationic PS. In vivo studies have shown that these PS provide effective inhibition of the tumor growth with an increase in the lifespan of mice in the group by more than 130%, and more than 50% survival of mice in the group. CONCLUSIONS: Photosensitizers based on polycationic derivatives of synthetic bacteriochlorin have high photodynamic efficacy caused by the induction of necrosis and apoptosis of cancer cells, including cancer stem cells, and a sharp decrease of mitotic and proliferative activity. Studied polycationic photosensitizers are much more effective at destroying cancer stem cells and newly formed cancer vessels in comparison with anionic photosensitizers, and ensure the cessation of tumor blood flow without hemorrhages and thrombosis.

Enhanced reduction of polymicrobial biofilms on the orthodontic brackets and enamel surface remineralization using zeolite-zinc oxide nanoparticles-based antimicrobial photodynamic therapy.

The aim of this study was to evaluate the anti-biofilm and anti-metabolic activities of zeolite-zinc oxide nanoparticles (Zeo/ZnONPs)-based antimicrobial photodynamic therapy (aPDT) against pre-formed polymicrobial biofilms on the orthodontic brackets, as well as, assess the remineralization efficacy on polymicrobial biofilms induced enamel lesions. Following synthesis and characterization of Zeo/ZnONPs, cell cytotoxicity, hemolytic effect, and intracellular reactive oxygen species (ROS) production were determined. The anti-biofilm and anti-metabolic activities of aPDT using different concentrations of Zeo/ZnONPs were investigated. Microhardness tester and DIAGNOdent Pen were used to evaluate the changes of remineralization degree on the treated enamel slabs duration 1 and 3 months. No significant cytotoxicity and erythrocyte hemolysis were observed in treated cells with Zeo/ZnONPs. When irradiated, suggesting that the Zeo/ZnONPs were photoactivated, generating ROS and leading to reduce dose-dependently the cell viability and metabolic activity of polymicrobial biofilms. Also, the enamel surface microhardness value of exposed enamel showed a steady increase with the concentration of Zeo/ZnONPs. No statistically significant differences were shown between aPDT and sodium fluoride varnish as the control group. Overall, Zeo/ZnONPs-based aPDT with the greatest remineralization efficacy of enamel surface can be used as an anti-biofilm therapeutic method, which is involved with their potent ability to produce ROS.

Photodynamic therapy procedures in coronavirus (COVID-19) outbreak: perception of health risks among clinical dental faculty and dental students.

OBJECTIVE: The aim of the study was to investigate clinical faculty members and final year dentistry students' perceptions regarding their health concerns and risks of performing photodynamic therapy (PDT) procedure in dental clinics amidst the COVID-19 pandemic. SUBJECTS AND METHODS: A 21-item questionnaire comprising open and closed questions was sent to dental faculty members (n=43) and final year dentistry students (n=99) of Riyadh Elm University during mid-January 2021 that ended only after two weeks. The survey included health risks perception of performing PDT procedures, the impact of the COVID-19 outbreak on PDT performance and stress levels, perceived efficacy of the preventive steps, perception of the effect of the probable suspension of PDT procedure in dental clinics, and influence of alternative teaching methods of PDT procedure on clinical competence were reported. RESULTS: A response rate of 82% for faculty members (n=35) and 75% for students (n=74) was recorded. 91% of faculty members and 95% of students felt that their health was not at risk during performing PDT procedure in dental clinics amidst the COVID-19. 82% of faculty and 83% of students expressed that the PPE and universal preventive steps to perform PDT procedure were enough for preventing the cross-infection with the virus. 89% of faculty members and 91% of students thought that a provisional suspension of PDT procedures in dental clinics would assist in containment of the virus and reduce the infection risk from the contact and not the PDT procedure. CONCLUSIONS: Students and faculty members reported that their health is not at risk while performing PDT procedure in dental clinics amidst the COVID-19 outbreak.

Contemporary approaches and future perspectives of antibacterial photodynamic therapy (aPDT) against methicillin-resistant Staphylococcus aureus (MRSA): A systematic review.

The high prevalence of methicillin-resistant Staphylococcus aureus (MRSA) causing skin and soft tissue infections in both the community and healthcare settings challenges the limited options of effective antibiotics and motivates the search for alternative therapeutic solutions, such as antibacterial photodynamic therapy (aPDT). While many publications have described the promising anti-bacterial activities of PDT in vitro, its applications in vivo and in the clinic have been very limited. This limited availability may in part be due to variabilities in the selected photosensitizing agents (PS), the variable testing conditions used to examine anti-bacterial activities and their effectiveness in treating MRSA infections. We thus sought to systematically review and examine the evidence from existing studies on aPDT associated with MRSA and to critically appraise its current state of development and areas to be addressed in future studies. In 2018, we developed and registered a review protocol in the International Prospective Register of Systematic Reviews (PROSPERO) with registration No: CRD42018086736. Three bibliographical databases were consulted (PUBMED, MEDLINE, and EMBASE), and a total of 113 studies were included in this systematic review based on our eligibility criteria. Many variables, such as the use of a wide range of solvents, pre-irradiation times, irradiation times, light sources and light doses, have been used in the methods reported by researchers, which significantly affect the inter-study comparability and results. On another note, new approaches of linking immunoglobulin G (IgG), antibodies, efflux pump inhibitors, and bacteriophages with photosensitizers (PSs) and the incorporation of PSs into nano-scale delivery systems exert a direct effect on improving aPDT. Enhanced activities have also been achieved by optimizing the physicochemical properties of the PSs, such as the introduction of highly lipophilic, poly-cationic and site-specific modifications of the compounds. However, few in vivo studies (n = 17) have been conducted to translate aPDT into preclinical studies. We anticipate that further standardization of the experimental conditions and assessing the efficacy in vivo would allow this technology to be further applied in preclinical trials, so that aPDT would develop to become a sustainable, alternative therapeutic option against MRSA infection in the future.

Baseline factors predicting the need for corneal crosslinking in patients with keratoconus.

INTRODUCTION: The primary purpose of crosslinking is to halt the progression of ectasia. We retrospectively assessed the condition of keratoconus patients who were followed-up at least twice after the initial examination to evaluate keratoconus progression, to identify definitive factors to predict a later need for corneal crosslinking (CXL). METHODS: The medical charts of 158 eyes of 158 keratoconus patients (112 males and 46 females; mean age, 27.8 ± 11.7 years), who were followed up at the Department of Ophthalmology, Keio University School of Medicine at least twice after the initial examination to evaluate keratoconus progression were retrospectively reviewed. Best-spectacle corrected visual acuity, intraocular pressure, steepest corneal axis on the anterior float (Ks), thinnest corneal thickness according to Pentacam® HR, and corneal endothelial cell density were assessed. Gender, age, onset age of keratoconus, history of atopic dermatitis, and Pentacam® indices were also recorded. CXL was performed when the eye showed significant keratoconus progression, an increase in the steepest keratometric value, or an increase in the spherical equivalent or cylinder power of the manifest refraction by more than 1.0 D versus the respective values 2 years prior. Predictor variables and the requirement for CXL were analyzed using logistic regression. RESULTS: Fifty-eight eyes required CXL treatment. The best predictor of the requirement for CXL was patient age, followed by the Pentacam® Rmin (the minimum sagittal curvature evaluated by Pentacam®) value. The incidence of CXL was 86.4% in the < 20 years age group, with an Rmin of ≤ 5.73 mm, whereas 10.8% in the ≥ 27 years age group with an Rmin > 5.73 mm underwent treatment. CONCLUSIONS: An age of < 20 years and an Rmin value of ≤ 5.73 mm predicted keratoconus progression and the requirement for CXL treatment in the near future.

Iridium(III) Complex-Derived Polymeric Micelles with Low Dark Toxicity and Strong NIR Excitation for Phototherapy and Chemotherapy.

Iridium(III) complexes are potent candidates for photodynamic therapy. However, their clinical usage is impeded by their poor water solubility, high dark toxicity, and negligible absorption in near-infrared region (NIR region). Here, it is proposed to solve these challenges by developing an iridium(III) complexe-based polymeric micelle system. This system is self-assembled using an iridium(III) complex-containing amphiphilic block polymer. The upconversion nanoparticles are included in the polymeric micelles to permit NIR excitation. Compared with the nonformulated iridium(III) complexes, under NIR stimulation, this polymeric micelle system exhibits higher 1 O2 generation efficiency, negligible dark toxicity, excellent tumor-targeting ability, and synergistic phototherapy-chemotherapy effect both in vitro and in vivo.

Current therapies for actinic keratosis.

Actinic keratosis (AK) is a very common skin disease caused by chronic sun damage, which in 75% of cases arises on chronically sun-exposed areas, such as face, scalp, neck, hands, and forearms. AKs must be considered an early squamous cell carcinoma (SCC) for their probable progression into invasive SCC. For this reason, all AK should be treated, and clinical follow-up is recommended. The aims of treatment are: (i) to clinically eradicate evident and subclinical lesions, (ii) to prevent their evolution into SCC, and (iii) to reduce the number of relapses. Among available treatments, it is possible to distinguish lesion-directed therapies and field-directed therapies. Lesion-directed treatments include: (i) cryotherapy; (ii) laser therapy; (iii) surgery; and (iv) curettage. Whereas, field-directed treatments are: (i) 5-fluorouracil (5-FU); (ii) diclofenac 3% gel; (iii) chemical peeling; (iv) imiquimod; and (v) photodynamic therapy (PDT). Prevention plays an important role in the treatment of AKs, and it is based on the continuous use of sunscreen and protective clothing. This review shows different types of available treatments and describes the characteristics and benefits of each medication, underlining the best choice.

Techniques to Improve Photodynamic Therapy.

Photodynamic therapy [dye-light therapy] is an excellent technique for use in detection and treatment of cancerous tissues. While this therapy is effective, it is limited by the phototoxic reactions that can occur in the surrounding normal tissues. These damaging side effects are of particular importance when treating neurosensory organs, such as the human eye. We report here new treatment strategies to enhance photodynamic effectiveness while limiting side effects to normal tissues.

Approche diagnostique et thérapeutique de la vasculopathie polypoïdale choroïdienne. Recommandations de la Fédération France Macula.

PURPOSE: To update the medical literature on the diagnostic and therapeutic approach to polypoidal choroidal vasculopathy (PCV) and to propose a treatment algorithm in agreement with French market approval, supported by the France Macula Federation (FFM). METHODS: Literature review and expert opinion. RESULTS: The diagnosis of PCV is based on multimodal imaging, including indocyanine green angiography (ICGA), which is considered the gold standard for the diagnosis of PCV. Regarding the therapeutic management of PCV, the FFM recommends treating PCV first-line either by monotherapy with intra-vitreal anti-vascular endothelial growth factor (anti-VEGF) injections, or by a combined treatment of photodynamic therapy (PDT) with Verteporfin and intra-vitreal anti-VEGF injections, depending on the location of the PCV.

TREatment of ATopic eczema (TREAT) Registry Taskforce: an international Delphi exercise to identify a core set of domains and domain items for national atopic eczema photo- and systemic therapy registries.

BACKGROUND: Evidence of immunomodulatory therapies to guide clinical management of atopic eczema (AE) is scarce, despite frequent and often off-label use. Patient registries provide valuable evidence for the effects of treatments under real-world conditions that can inform treatment guidelines, give the opportunity for health economic evaluation and the evaluation of quality of care, as well as pharmacogenetic and dynamic research, which cannot be adequately addressed in clinical trials. OBJECTIVES: The TREatment of ATopic eczema (TREAT) Registry Taskforce aims to seek international consensus on a core set of domains and items ('what to measure') for AE research registries, using a Delphi approach. METHODS: Participants from six stakeholder groups were included: doctors, nurses, nonclinical researchers, patients, industry and regulatory body representatives. The eDelphi comprised three sequential online rounds, requesting participants to rate the importance of each proposed domain item. Participants could add domain items to the proposed list in round 1. A final consensus meeting was held to ratify the core set. RESULTS: Participants (n = 479) from 36 countries accessed the eDelphi platform, of whom 86%, 79% and 74% completed rounds 1, 2 and 3, respectively. At the face-to-face consensus meeting attended by 42 participants the final core set was established containing 19 domains with 69 domain items (49 baseline and 20 follow-up items). CONCLUSIONS: This core set of domains and items to be captured by national AE systemic therapy registries will standardize data collection and thereby allow direct comparability across registries and facilitate data pooling between countries. Ultimately, it will provide greater insight into the effectiveness, safety and cost-effectiveness of photo- and systemic immunomodulatory therapies.

Photodynamic therapy in the treatment of symptomatic oral lichen planus: A systematic review.

BACKGROUND: The aim of this systematic review was to assess the efficacy of photodynamic therapy (PDT) in the treatment of symptomatic oral lichen planus (OLP). METHODS: This systematic review aimed to address the following focused question: "Is PDT effective in the treatment of symptomatic OLP?" Indexed databases such as MEDLINE, EMBASE, and CENTRAL were searched up to and including August 2017. RESULTS: Six clinical studies were included. The risk of bias was considered high in 5 studies and moderate in one study. Parameters of PDT such as wavelengths, energy fluence, power density and exposure time ranged between 320-660 nm, 120 J/cm2 , 130 mW/cm2 , and 70-150 seconds, respectively. The follow-up period ranged from 4 to 48 weeks. All included studies reporting clinical scores showed that PDT was effective in the treatment of OLP in adult patients at follow-up. However, PDT did not show significant improvement when compared with steroid therapy. CONCLUSION: Photodynamic therapy appears to have some effect in the symptomatic treatment of OLP in adult patients. However, further randomized controlled trials with long follow-up period, standardized PDT parameters, and comparing the efficacy of PDT with steroid therapy are warranted to obtain strong conclusions in this regard.

Safety evaluation of repeated intravenous infusion of sinoporphyrin with and without PDT in rats.

Photodynamic therapy (PDT) is a promising antineoplastic modality in the oncology field. We assessed the safety of repeated intravenous administrations of sinoporphyrin, a porphyrin derivative, with and without illumination in rats. Toxicokinetic studies of single and multiple administrations of sinoporphyrin were also carried out. Sprague-Dawley rats were randomly assigned to the dark-toxicity and PDT groups. Animals in the dark toxicity group received an i.v. infusion of sinoporphyrin at 3 doses: 2 mg kg-1, 6 mg kg-1, and 18 mg kg-1. The PDT group included 2 doses of sinoporphyrin (2 mg kg-1 and 18 mg kg-1), and the rats received 60 J of 630 nm laser illumination 24 h after photosensitizer infusion. The treatments were repeated every 7 days for 5 cycles and were followed by a 14-day recovery period. Systematic analyses were conducted at the end of treatment and recovery periods. Blood samples were obtained 5 min, 30 min, 2 h, 8 h, 24 h, 48 h, 72 h, and 96 h after the first and fifth treatments for toxicokinetic studies. Sinoporphyrin-PDT led to the death of one out of 270 rats; the dead animal had been treated with 18 mg kg-1 sinoporphyrin and died at the end of the fifth PDT treatment. Liver injury, the primary toxicity observed in the study, was identified using biochemical tests, necropsy, and histopathology. Elevated white blood cell and neutrophil counts were found in the rats in both the dark toxicity and PDT groups. Skin lesions at the illumination site were obvious in the PDT group. Pigment deposits were detected in multiple organs such as the liver, spleen, lymph nodes, and ovaries in the 6 mg kg-1 and 18 mg kg-1 groups. No other abnormalities were observed. The toxicokinetic parameters of single and multiple sinoporphyrin administrations were calculated and compared. Repeated sinoporphyrin administrations both alone and in combination with laser illumination were tolerable, and all toxicities were transient. The no observed adverse effect level (NOAEL) for repeated sinoporphyrin administration and sinoporphyrin-PDT was 6 mg kg-1 and 2 mg kg-1, respectively. Further studies are warranted.

[Non-muscle invasive bladder cancer : Current aspects of diagnostics, local therapy options and the update of the 2016 WHO classification]. / Nichtmuskelinvasives Harnblasenkarzinom : Aktuelles zu Diagnoseverfahren, lokalen Therapieoptionen und zum Update der WHO-Klassifikation 2016.

INTRODUCTION: Urothelial carcinoma of the bladder is known as one of most common malignant tumors in the urogenital tract. Non-muscle invasive bladder cancer (NMIBC) in particular has a high recurrence rate and results in correspondingly high costs for the public health system. METHODS: To improve the recurrence rate and the prognosis of NMIBC the diagnosis, resection technique, adjuvant instillation therapy and exact histopathological classification of tumor lesions are indispensable. This article gives an overview on the current developments in this field. RESULTS: The current European Association of Urology (EAU) guidelines and the preliminary version of the German S3 guidelines on bladder cancer list photodynamic diagnosis (PDD) and narrow band imaging (NBI) as diagnostic procedures for tumors of the bladder. The trend for resection of bladder tumors is towards the use of en bloc resection using various techniques. Furthermore, an update of the WHO classification aims at a better identification and prognosis of the different risk groups of NMIBC. CONCLUSION: The treatment of NMIBC can only be improved by the combination of optimized diagnosis, precise tumor resection, improved adjuvant intravesical therapy and correct histopathological evaluation of tumors.

Photodynamic Therapy: A Clinical Consensus Guide.

BACKGROUND: The American Society of Dermatologic Surgery (ASDS) periodically develops consensus documents for its members concerning various aspects of dermatologic surgery. Advances in photodynamic therapy (PDT) have been many and PDT use has been established in a variety of skin conditions. OBJECTIVE: The ASDS board of directors proposed a committee of experts in the field to develop consensus documents on different treatments. An expert panel reviewed the literature on PDT and discussed the findings. The consensus was reached with evidence-based recommendations on different clinical applications for PDT. PATIENTS AND METHODS: This consensus document includes discussions regarding PDT, including different photosensitizers and various light source activators, historical perspective, mechanism of action, various therapeutic indications and expected outcomes, pre- and post-care, and management of adverse outcomes. RESULTS: Photodynamic therapy is highly effective for pre-cancerous lesions, superficial nonmelanoma skin cancers, inflammatory acne vulgaris and other conditions. New protocols including laser mediated PDT significantly improve results for several indications. CONCLUSION: The ASDS consensus document on PDT will be helpful for educating members on safe and effective PDT for a variety of indications.

[Approaches to phototherapy in children with chronic dermatosis (review of literature)].

The article covers main aspects of phototherapy and photochemotherapy in treatment of skin diseases in children, risks of such methods usage, prophylactic and therapeutic measures, and precaution means for such treatment in pediatrics.

Photodynamic therapy for the treatment of different severity of acne: A systematic review.

INTRODUCTION: Acne, a disease of pilosebaceous unit, is a common dermatologic disorder affecting about 80%-95% of people in both genders in adulthood. The available treatment options are conventional topical and/or oral medications, which are associated with adverse effects, partial response only, contraindications and reoccurrences. This necessitates the need for the introduction of novel treatment for improving acne lesions. OBJECTIVE: The aim of writing this review is to provide evidence-based information regarding safety and efficacy of PDT in treating acne lesions. METHOD: The search term 'Acne and PDT' were entered into a search of the National Library of Medicine's PubMed Database. The search returned a total of 143 sources among which 36 studies pertaining to the use of PDT in acne are included in this review article. RESULT: 36 clinical trials were selected among which 24 trials were performed to see the effect of PDT in acne whereas 12 trials compared the effect of PDT with light or laser alone therapy. Among 24 trials that used PDT only, 3 were clinical trials with control, 14 were clinical trials without control, 6 were randomized controlled trials (RCT) and 1 was retrospective study. On the basis of results of these trials, it is seen that PDT is safe and effective method of treatment for acne lesions. Studies have shown that PDT can control both inflammatory and non-inflammatory acne lesions and can improve all severity of lesions from mild to severe. CONCLUSION: Photodynamic therapy (PDT) has been extensively studied and found to be effective treatment modality for acne lesions. However, more RCTs are needed to establish standard guidelines regarding concentrations and incubation period of photosensitizers and optimal parameters of light sources. Further studies are needed to guide future research and help dermatologist to choose PDT as an effective treatment modality for treating acne lesions.

Daylight PDT with MAL - current data and practical recommendations of an expert panel.

Photodynamic Therapy (PDT) is one of the standard treatment modalities for actinic keratoses (AKs). Daylight PDT (DL-PDT) with MAL cream is a rather recent development, which, instead of an artificial light source, uses daylight for the activation of the photosensitizer. The present review summarizes available data based on a selective literature search, highlights practical aspects, and reflects the authors' expert knowledge in using DL-PDT. With respect to efficacy, study data shows that DL-PDT is noninferior to conventional PDT (cPDT). However, given that DL-PDT is markedly less painful, it is significantly better tolerated than cPDT. In Europe, DL-PDT can be performed from March to October, on sunny as well as on cloudy days. UV protection of untreated areas of the body should be observed. Outside temperature should not fall below 10°C. On hot days, patients should be advised to stay in the shade if necessary. Representing a useful addition to current therapeutic options, DL-PDT with MAL cream is, among others, suitable for patients with field cancerization and/or those who have experienced severe pain associated with cPDT.

Epigenetically Enhanced Photodynamic Therapy (ePDT) is Superior to Conventional Photodynamic Therapy for Inducing Apoptosis in Cutaneous T-Cell Lymphoma.

Conventional photodynamic therapy with aminolevulinate (ALA-PDT) selectively induces apoptosis in diseased cells and is highly effective for treating actinic keratoses. However, similar results are achieved only in a subset of patients with cutaneous T-cell lymphoma (CTCL). Our previous work shows that the apoptotic resistance of CTCL correlates with low expression of death receptors like Fas cell surface death receptor (FAS), and that methotrexate upregulates FAS by inhibiting the methylation of its promoter, acting as an epigenetic derepressor that restores the susceptibility of FAS-low CTCL to caspase-8-mediated apoptosis. Here, we demonstrate that methotrexate increases the response of CTCL to ALA-PDT, a concept we refer to as epigenetically enhanced PDT (ePDT). Multiple CTCL cell lines were subjected to conventional PDT versus ePDT. Apoptotic biomarkers were analyzed in situ with multispectral imaging analysis of immunostained cells, a method that is quantitative and 5× more sensitive than standard immunohistology for antigen detection. Compared to conventional PDT or methotrexate alone, ePDT led to significantly greater cell death in all CTCL cell lines tested by inducing greater activation of caspase-8-mediated extrinsic apoptosis. Upregulation of FAS and/or tumor necrosis factor-related apoptosis-inducing ligand pathway components was observed in different CTCL cell lines. These findings provide a rationale for clinical trials of ePDT for CTCL.

European Dermatology Forum Guidelines on topical photodynamic therapy.

Topical photodynamic therapy (PDT) is a widely approved therapy for actinic keratoses, squamous cell carcinoma in-situ, superficial and certain thin basal cell carcinomas. Recurrence rates are typically equivalent to existing therapies, although inferior to surgery for nodular basal cell carcinoma. PDT can be used both as a lesional or as a field therapy and has the potential to delay/reduce the development of new lesions. PDT has also been studied for its place in the treatment of, as well as its potential to prevent, superficial skin cancers in immune-suppressed patients, although sustained clearance rates are lower than for immunocompetent individuals. Many additional indications have been evaluated, including photo-rejuvenation and inflammatory and infective dermatoses. This S2 guideline considers all current and emerging indications for the use of topical photodynamic therapy in Dermatology, prepared by the PDT subgroup of the European Dermatology Forum guidelines committee. It presents consensual expert recommendations reflecting current published evidence. An unabridged version of this guideline is available online at: http://www.euroderm.org/edf/index.php/edf-guidelines.