In Vitro Effect of Epigallocatechin Gallate on Heme Synthesis Pathway and Protoporphyrin IX Production.

Photodynamic therapy (PDT) treats nonmelanoma skin cancer. PDT kills cells through reactive oxygen species (ROS), generated by interaction among cellular O2, photosensitizer and specific light. Protoporphyrin IX (PpIX) is a photosensitizer produced from methyl aminolevulinate (MAL) by heme group synthesis (HGS) pathway. In PDT-resistant cells, PDT efficacy has been improved by addition of epigallocatechin gallate (EGCG). Therefore, the aim of this work is to evaluate the effect of EGCG properties over MAL-TFD and PpIX production on A-431 cell line. EGCG's role over cell proliferation (flow cytometry and wound healing assay) and clonogenic capability (clonogenic assay) was evaluated in A-431 cell line, while the effect of EGCG over MAL-PDT was determined by cell viability assay (MTT), PpIX and ROS detection (flow cytometry), intracellular iron quantification and gene expression of HGS enzymes (RT-qPCR). Low concentrations of EGCG (<50 µM) did not have an antiproliferative effect over A-431 cells; however, EGCG inhibited clonogenic cell capability. Furthermore, EGCG (<50 µM) improved MAL-PDT cytotoxicity, increasing PpIX and ROS levels, exerting a positive influence on PpIX synthesis, decreasing intracellular iron concentration and modifying HGS enzyme gene expression such as PGB (upregulated) and FECH (downregulated). EGCG inhibits clonogenic capability and modulates PpIX synthesis, enhancing PDT efficacy in resistant cells.

Epigallocatechin Gallate Enhances MAL-PDT Cytotoxic Effect on PDT-Resistant Skin Cancer Squamous Cells.

Photodynamic therapy (PDT) has been used to treat certain types of non-melanoma skin cancer with promising results. However, some skin lesions have not fully responded to this treatment, suggesting a potential PDT-resistant phenotype. Therefore, novel therapeutic alternatives must be identified that improve PDT in resistant skin cancer. In this study, we analyzed the cell viability, intracellular protoporphyrin IX (PpIX) content and subcellular localization, proliferation profile, cell death, reactive oxygen species (ROS) detection and relative gene expression in PDT-resistant HSC-1 cells. PDT-resistant HSC-1 cells show a low quantity of protoporphyrin IX and low levels of ROS, and thus a low rate of death cell. Furthermore, the resistant phenotype showed a downregulation of HSPB1, SLC15A2, FECH, SOD2 and an upregulation of HMBS and BIRC5 genes. On the other hand, epigallocatechin gallate catechin enhanced the MAL-PDT effect, increasing levels of protoporphyrin IX and ROS, and killing 100% of resistant cells. The resistant MAL-PDT model of skin cancer squamous cells (HSC-1) is a reliable and useful tool to understand PDT cytotoxicity and cellular response. These resistant cells were successfully sensitized with epigallocatechin gallate catechin. The in vitro epigallocatechin gallate catechin effect as an enhancer of MAL-PDT in resistant cells is promising in the treatment of difficult skin cancer lesions.

Field cancerization treatment using topical photodynamic therapy: A comparison between two aminolevulinate derivatives.

The objective of this study was to evaluate and compare the clinical response to PDT (Photodynamic Therapy) in field cancerization using two aminolevulinate derivatives. Forty patients with multiple actinic keratosis (AK) on forearms and hands scattered received two sessions of ALA and MAL-PDT at 630 nm (36 J/cm2). The AK clearance rate was 72 % for both drugs with a significant decrease in AK observed clinically (p < 00,001). Clinical improvement in field cancerization using two aminolevulinate derivatives in PDT is proven with no significant difference in the efficacy of drugs.

Long Term Effectiveness of Photodynamic Therapy for CIN Treatment.

(1) Background: Cervical cancer is the third most commonly diagnosed cancer and the fourth leading cause of cancer death in women worldwide. The highest incidence rates are in Africa, followed by South-Central Asia and South America. According to the Brazilian National Institute of Cancer (INCA), 16,370 new cases of cervical cancer were estimated for each year of the biennium of 2018-2019. About 90% of cervical cancers originate from the malignant progression of cervical intraepithelial neoplasia (CIN) which is classified based on cytohistological characteristics (low- and high-grade lesions). The present study reports the long-term effectiveness of topical photodynamic therapy (PDT) for CIN grades 1 and 2/3 with up to two years of follow up. (2) Methods: A total of 56 patients with CIN 1, ten with CIN 2, and 14 patients for the placebo group were enrolled in this study. (3) Results: 75% (n = 42) of CIN 1 patients presented a complete response to PDT and only 23.2% (n = 13) of recurrence, progression, and/or lesions remaining two years after PDT. For CIN 2/3 patients, 90% were observed to be cured after one and two years of follow up. (4) Conclusions: PDT presented best results two years after a non-invasive, fast, and low-cost procedure and in comparison with the placebo group, preventing the progression of cervical intraepithelial neoplasia and preserving the cervix.

Topical and intradermal delivery of PpIX precursors for photodynamic therapy with intense pulsed light on porcine skin model.

In order to purposely decrease the time of the photodynamic therapy (PDT) sessions, this study evaluated the effects of PDT using topical and intradermal delivery of two protoporphyrin (PpIX) precursors with intense pulsed light (IPL) as irradiation source. This study was performed on porcine skin model, using an IPL commercial device (Intense Pulse Light, HKS801). IPL effect on different administration methods of two PpIX precursors (ALA and MAL) was investigated: a topical cream application and an intradermal application using a needle-free, high-pressure injection system. Fluorescence investigation showed that PpIX distribution by needle-free injection was more homogeneous than that by cream, suggesting that a shorter drug-light interval in PDT protocols is possible. The damage induced by IPL-PDT assessed by histological analysis mostly shows modifications in collagens fibers and inflammation signals, both expected for PDT. This study suggested an alternative protocol for the PDT treatment, possibility half of the incubation time and with just 3 min of irradiation, making the IPL-PDT, even more, promising for the clinical treatment.

Randomized clinical trial testing the efficacy and safety of 0.5% colchicine cream versus photodynamic therapy with methyl aminolevulinate in the treatment of skin field cancerization: study protocol.

BACKGROUND: The primary clinical manifestation of skin field cancerization is the presence of actinic keratoses (AKs). Current treatments for AKs related to skin field cancerization include photodynamic therapy (PDT) and colchicine. The objective of this study is to evaluate the efficacy and safety of 0.5% colchicine cream versus PDT with methyl aminolevulinate (MAL-PDT) in the treatment of skin field cancerization. METHODS: In a randomized controlled and open clinical trial with a blind histopathological and immunohistochemical analysis, 36 patients with up to 10 AKs on their forearms will be included from the outpatient clinic. The forearms will be randomized into two groups, clinically evaluated and biopsied for histopathology and immunohistochemistry (p53 and Ki67). One forearm will be treated with 0.5% colchicine cream for 10 days, and the other forearm will receive one session of MAL-PDT; the forearms will subsequently be reassessed clinically and histologically after 60 days (T60) of treatment. The primary endpoint will be the point of complete clearance of AKs in T60. The sample size will enable a detection in the reduction of over 10% in AK counts between the groups with power of 0.9 and an alpha of 0.05, accounting for an estimated dropout rate of 10%, resulting in 36 patients (72 forearms). All participants included in the randomized study will be part of the analysis, and the final outcomes of any dropouts will be the value of their last visit (LOCF). The statistical analysis will be performed using SPSS 22.0, and a p value < 5% will be considered to be significant. DISCUSSION: It is expected that colchicine will be superior to MAL-PDT in reducing AKs and in the skin field cancerization, and there will be good tolerability in both groups. Colchicine intervention is novel in that it provides a new alternative to MAL-PDT. Moreover, this drug is inexpensive that may be a potential treatment of skin field cancerization that can be prescribed in public health systems with good results. TRIAL REGISTRATION: The trial is registered in Brazilian Registry for Clinical Trials (Registration number: RBR-8y3sj9 , date assigned May 4, 2016, retrospectively registered).

Daylight Photodynamic Therapy Versus 5-Fluorouracil for the Treatment of Actinic Keratosis: A Case Series.

INTRODUCTION: The incidence of actinic keratosis (AK) continues to increase worldwide. Currently available options for the treatment of AK include topical 5-fluorouracil (5-FU) and daylight-mediated photodynamic therapy (DL-PDT). This split-face pilot study compared DL-PDT using 16% methyl aminolevulinate (MAL) cream versus 5-FU cream in patients with AK on the face/scalp. METHODS: Five male subjects (mean age 70 years) with grade I-III AK on the face/scalp were enrolled. Subjects received a single session of DL-PDT with 16% MAL on one side and topical 5% 5-FU for 21 days on the other side. Evaluations of efficacy, safety, and subject satisfaction were conducted 48 h, 7 days, 14 days, 1 month, and 3 months after treatment. RESULTS: At 3 months, the lesion complete response rate was 80% and 93% for DL-PDT and 5-FU, respectively. Lesion partial response was 20% and 7%, respectively. Fewer treatment-related adverse events (AEs) were reported with DL-PDT than with 5-FU, and they resolved spontaneously in 5-7 and 27-30 days, respectively. Subjects preferred DL-PDT because of the lower incidence of AEs and rapid recovery compared with 5-FU. CONCLUSION: DL-PDT is a convenient alternative to 5-FU with good efficacy and a favorable safety profile, allowing patients to effectively treat their AK without compromising their social life. FUNDING: Galderma.

Synergistic enhancement of antitumor effect of ß-Lapachone by photodynamic induction of quinone oxidoreductase (NQO1).

ß-Lapachone is a phytochemotherapeutic originally isolated from Lapacho tree whose extract has been used medicinally for centuries. It is well known that NAD(P)H:quinone oxidoreductase (NQO1) activity is the principal determinant of ß-Lapachone cytotoxicity. As NQO1 is overexpressed in most common carcinomas, recent investigations suggest its potential application against cancer. Photodynamic therapy (PDT) is a clinically approved and rapidly developing cancer treatment. PDT involves the administration of photosensitizer (PS) followed by local illumination with visible light of specific wavelength. In the presence of oxygen molecules, the light illumination of PS can lead to a series of photochemical reactions and consequently the generation of cytotoxic reactive oxygen species (ROS). It has been reported that ß-Lapachone synergistically interacts with ionizing radiation, hyperthermia and cisplatin and that the sensitivity of cells to ß-Lapachone is closely related to the activity of NQO1. So, the present study aimed to investigate the feasibility of PDT to increase the anticancer effect of ß-Lapachone by up-regulating NQO1 expression on breast cancer MCF-7c3 cells. NQO1 expression was evaluated by Western blot analysis at different times after PDT using ME-ALA as PS. The cytotoxicity of the photodynamic treatment and ß-Lapachone alone or in combination was determined by MTT assay and the combination index (CI)-isobologram method and the dose reduction index (DRI) analysis were used to assess the effect of drug combinations. Our studies for the first time demonstrated that the expression of NQO1 is induced 24h after photodynamic treatment. The sensitivity of cancer cells to ß-Lapachone treatment increased 24h after PDT and a synergistic inhibitory effect on MCF-7c3 cells was showed. Taken together, these results lead us to conclude that the synergistic interaction between ß-Lapachone and PDT in killing cells was consistent with the up-regulation of NQO1. The combination of ß-Lapachone and PDT is a potentially promising modality for the treatment of cancer.

Efecto de la terapia fotodinámica con metil-aminolevulinato (MAL) comparada con luz roja en el tratamiento de acné inflamatorio leve a moderado / Effectiveness of photodynamic therapy with methyl aminolevulinate (MAL) compared with red light alone in the treatment of acne

Introducción: El acné es una dermatosis inflamatoria frecuente. Habitualmente requiere tratamientos sistémicos no exentos de riesgos. La terapia fotodinámica (TFD) ha demostrado efectividad en el tratamiento del acné. Material y método: estudio prospectivo, aleatorizado, y controlado, comparando la TFD con metil-aminolevulinato (MAL) al 16 por ciento con la aplicación de luz roja sola en el tratamiento del acné inflamatorio leve a moderado. Se aleatorizaron los pacientes a dos grupos; en el primer grupo se realizó TFD con luz roja, previa aplicación de crema de metil-aminolevulinato 16 por ciento (MAL), a las semanas 0 y 2. Resultados: se incluyeron 36 pacientes con acné inflamatorio leve y moderado localizado en región facial. Se determinaron los cambios de grados de acné existiendo diferencias significativas en los cambios de grado a las semanas 2, 4 y 10 (p<0.001), siendo mayor la mejoría clínica del acné en el grupo TFD-MAL comparado con el grupo luz roja sola, pero observable en ambos grupos. Discusión: la fototerapia con luz roja, con o sin fotosensibilizante, representa una opción de tratamiento no invasivo, seguro y eficaz para el acné vulgar. Al combinar la fototerapia con sustancias tópicas, por ejemplo MAL, resulta de una acción sinérgica aditiva.

Introduction: Acne is a frequent inflammatory dermatoses. It usually requires systemic treatments that are not free of adverse events. Photodynamic therapy (PDT) had been shown to be effective in acne. Methods: a prospective, randomized controlled trial was done to evaluate the effectiveness of PDT with methyl aminolevulinate (MAL) compared with red light alone. Patients were randomized in two groups. In the first group PDT-MAL was applied at week 0and 2; and in the second groupred light alone was applied. Results: 36 patients were incluided with facial acne. Effectiveness was evaluated at weeks 2, 4 and 10 for both groups. A statistically significant difference (p<0.001) was found favoring PDT-MAL group. Both groups showed and improvement in cane severity. Discussion: PDT-MAL and red light therapy are an effective and safe treatment option for acne. Combining PDT with MAL is more effective than red light alone.

Terapia fotodinámica con metil aminolevulinato y ácido 5-aminolevulínico en acné inflamatorio leve y moderado: experiencia clínica / Photodynamic therapy with 5-aminolevulinic acid and methyl aminolevulinate for mild to moderate inflammatory acne: clinical experience

Introducción: La terapia fotodinámica (TFD) con ácido 5-aminolevulínico (ALA) y metil aminolevulinato (MAL) ha mostrado utilidad en el manejo del acné inflamatorio. Métodos: Dos grupos de cuatro pacientes cada uno, portadores de acné inflamatorio leve o moderado. Se realizaron dos sesiones de TFD separadas por dos semanas: un grupo fue tratado con MAL y luz roja y el otro, con ALA y luz azul. Se midió la severidad del acné con escala de 6 puntos y se consideró éxito clínico los grados 0 y 1. Resultados: En ambos grupos se observó éxito clínico a las 12 semanas post tratamiento, quedando con pigmentación residual, escasos comedones y menos de 10 pápulas. Se observaron efectos adversos tolerables, siendo los más importantes el eritema y la descamación. Conclusión: La TFD con ALA y MAL es una buena alternativa terapéutica para aquellos pacientes con acné inflamatorio leve y moderado que no responden o tienen contraindicación a los tratamientos convencionales.

Introduction: Photodynamic therapy with methyl aminolevulinate (MAL) and 5-aminolevulinic acid (ALA) has shown to be useful in the management of inflammatory acne. Methods: Two groups of 4 patients each with mild to moderate inflammatory acne. Two PDT sessions were performed within a 2 week interval; one group was treated with MAL and red light, and the other with ALA and blue light. Acne severity was measured with a 6-point scale and clinical success was considered between grades 0 and 1. Results: In both groups, clinical success was observed at 12 weeks post treatment, leaving residual pigmentation, scarce comedones and less than 10 papules. Tolerable side effects were observed, being the most important erythema and desquamation. Conclusion: PDT with ALA and MAL is a good therapeutic option for patients with mild to moderate inflammatory acne who do not respond or have contraindications to conventional treatments.