Indole 3-acetic acid-photodynamic therapy in the treatment of multiple actinic keratoses: A proof of concept pilot study

Role of AHR Ligands in Skin Homeostasis and Cutaneous Inflammation

Aryl hydrocarbon receptor (AHR) is an important regulator of skin barrier function. It also controls immune-mediated skin responses. The AHR modulates various physiological functions by acting as a sensor that mediates environment–cell interactions, particularly during immune and inflammatory responses. Diverse experimental systems have been used to assess the AHR’s role in skin inflammation, including in vitro assays of keratinocyte stimulation and murine models of psoriasis and atopic dermatitis. Similar approaches have addressed the role of AHR ligands, e.g., TCDD, FICZ, and microbiota-derived metabolites, in skin homeostasis and pathology. Tapinarof is a novel AHR-modulating agent that inhibits skin inflammation and enhances skin barrier function. The topical application of tapinarof is being evaluated in clinical trials to treat psoriasis and atopic dermatitis. In the present review, we summarize the effects of natural and synthetic AHR ligands in keratinocytes and inflammatory cells, and their relevance in normal skin homeostasis and cutaneous inflammatory diseases.

Nanocarriers for Photodynamic Therapy Intended to Cutaneous Tumors

Photodynamic Therapy (PDT) is a therapeutic modality used for several malignant and premalignant skin disorders, including Bowen's disease skin cancers and Superficial Basal Cell Carcinoma (BCC). Several photosensitizers (PSs) have been explored for tumor destruction of skin cancers, after their activation by a light source of appropriate wavelength. Topical release of PSs avoids prolonged photosensitization reactions associated with systemic administration; however, its clinical usefulness is influenced by its poor tissue penetration and the stability of the active agent. Nanotechnology-based drug delivery systems are promising tool to enhance the efficiency for PDT of cancer. This review focuses on PSs encapsulated in nanocarriers explored for PDT of skin tumors.

6-Nitro-Quinazolin-4(3H)-one Exhibits Photodynamic Effects and Photodegrades Human Melanoma Cell Lines. A Study on the Photoreactivity of Simple Quinazolin-4(3H)-ones

Photochemo and photodynamic therapies are minimally invasive approaches for the treatment of cancers and powerful weapons for competing bacterial resistance to antibiotics. Synthetic and naturally occurring quinazolinones are considered privileged anticancer and antibacterial agents, with several of them to have emerged as commercially available drugs. In the present study, applying a single-step green microwave irradiation mediated protocol we have synthesized eleven quinazolinon-4(3H)-ones, from cheap readily available anthranilic acids, in very good yields and purity. These products were irradiated in the presence of pBR322 plasmid DNA under UVB, UVA and visible light. Four of the compounds proved to be very effective DNA photocleavers, at low concentrations, being time and concentration dependent as well as pH independent. Participation of reactive oxygen species was related to the substitution of quinazolinone derivatives. 6-Nitro-quinazolinone in combination with UVA irradiation was found to be in vitro photodestructive for three cell lines; glioblastoma (U87MG and T98G) and mainly melanoma (A-375). Thus, certain appropriately substituted quinazolinones may serve as new lead photosensitizers for the development of promising biotechnological applications and as novel photochemo and photodynamic therapeutics.

Novel Rifampicin and Indocyanine Green Co-Loaded Perfluorocarbon Nanodroplets Provide Effective In Vivo Photo-Chemo-Probiotic Antimicrobility against Pathogen of Acne Vulgaris Cutibacterium acnes

Acne vulgaris is one of the most prevalent dermatological diseases among adolescents and is often associated with overgrowth of Cutibacterium acnes (C. acnes) in the pilosebaceous units. In this study, we aimed to develop novel rifampicin (RIF) and indocyanine green (ICG) co-loaded perfluorocarbon nanodroplets named RIPNDs which can simultaneously provide photo-, chemo-, and probiotic-antimicrobility, and explore their efficacy in treatment of C. acnes in vitro and in vivo. The RIPNDs were first characterized as being spherical in shape, with a size of 238.6 ± 7.51 nm and surface charge of -22.3 ± 3.5 mV. Then, the optimal dosages of Staphylococcus epidermidis-produced fermentation product medium (FPM) and RIPND were determined as 25% (v/v) and [RIF]/[ICG] = 3.8/20 μM, respectively, based on the analyses of inhibition zone and cytotoxicity in vitro. Through the in vivo study using C. acnes-inoculated mice, our data showed that the group treated with FPM followed by RIPNDs + near infrared (NIR) irradiation obtained the least granulocytes/macrophage-inflammatory protein 2 expression level in the epidermis, and showed a significantly lower microbial colony population compared to the groups treated with equal amount of RIF, FPM, RIPNDs, and/or combination of the above ± NIR. These results indicated that the RIPND-mediated photo-chemo-probiotic therapeutics was indeed able to rapidly suppress inflammatory response of the skin and provide a robust antibacterial effect against C. acnes with limited use of antibiotics. Taken altogether, we anticipate that the RIPND is highly potential for use in the clinical treatment of acne vulgaris.

Swiss (German) Version of the Actinic Keratosis Quality of Life questionnaire

BACKGROUND

Actinic keratosis (AK) is a sun-induced skin lesion that may progress to invasive squamous cell carcinoma of the skin. Recently, the Actinic Keratosis Quality of Life questionnaire (AKQoL) was designed for patients with AK in Denmark as a specific quality of life instrument for AK patients.

OBJECTIVE

The objective of this study was to adapt the AKQoL for the German language region of Switzerland and to evaluate its psychometric properties (validity, reliability).

METHODS

Translation and cultural adaptation of the questionnaire were assessed by using the technique of cognitive interviewing. During the translation process, 34 patients with AK from the Department of Dermatology, University Hospital Zurich, were interviewed in 3 sessions of cognitive interviewing. The translated questionnaire was then distributed together with the Dermatology Life Quality Index (DLQI) to a second group of 113 patients for validation and reliability testing. Within this group, we measured the internal consistency by the Cronbach coefficient α and Spearman correlation coefficient between the AKQoL and the DLQI.

RESULTS

The problems encountered during the translation process led to changes in 5 categories as described by Epstein: stylistic changes, change in breadth, change in actual meaning, change in frequency and time frame, change in intensity. We found a Cronbach α of 0.82, an acceptable internal consistency. The Spearman correlation coefficient between total scores of AKQoL and DLQI was 0.57.

CONCLUSION

We culturally adapted and validated a Swiss (German) version of the AKQoL questionnaire applicable for the population of a university center in Switzerland to measure and monitor the quality of life in patients with AK.