Non-Melanoma Skin Cancer and Vitamin D: The "Lost Sunlight" Paradox and the Oxidative Stress Explanation

Air pollution and skin diseases: A comprehensive evaluation of the associated mechanism

Air pollutants deteriorate the survival environment and endanger human health around the world. A large number of studies have confirmed that air pollution jeopardizes multiple organs, such as the cardiovascular, respiratory, and central nervous systems. Skin is the largest organ and the first barrier that protects us from the outside world. Air pollutants such as particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs) will affect the structure and function of the skin and bring about the development of inflammatory skin diseases (atopic dermatitis (AD), psoriasis), skin accessory diseases (acne, alopecia), auto-immune skin diseases (cutaneous lupus erythematosus(CLE) scleroderma), and even skin tumors (melanoma, basal cell carcinoma (BCC), squamous-cell carcinoma (SCC)). Oxidative stress, skin barrier damage, microbiome dysbiosis, and skin inflammation are the pathogenesis of air pollution stimulation. In this review, we summarize the current evidence on the effects of air pollution on skin diseases and possible mechanisms to provide strategies for future research.

Vitamin D in Melanoma: Potential Role of Cytochrome P450 Enzymes

Vitamin D is a promising anticancer agent for the prevention and treatment of several cancers, including melanoma. Low 25-hydroxyvitamin D levels, a routinely used marker for vitamin D, have been suggested as one of the factors in the development and progression of melanoma. The parent vitamin D needs activation by cytochrome P450 (CYP) enzymes to exert its actions via the vitamin D receptor (VDR). This review discusses the role of vitamin D in melanoma and how CYP-mediated metabolism can potentially affect the actions of vitamin D. Through interacting with the retinoid X receptor, VDR signaling leads to anti-inflammatory, antioxidative, and anticancer actions. Calcitriol, the dihydroxylated form of vitamin D3, is the most active and potent ligand of VDR. CYP27A1, CYP27B1, and CYP2R1 are involved in the activation of vitamin D, whereas CYP24A1 and CYP3A4 are responsible for the degradation of the active vitamin D. CYP24A1, the primary catabolic enzyme of calcitriol, is overexpressed in melanoma tissues and cells. Several drug classes and natural health products can modulate vitamin D-related CYP enzymes and eventually cause lower levels of vitamin D and its active metabolites in tissues. Although the role of vitamin D in the development of melanoma is yet to be fully elucidated, it has been proposed that melanoma prevention may be significantly aided by increased vitamin D signaling. Furthermore, selective targeting of the catabolic enzymes responsible for vitamin D degradation could be a plausible strategy in melanoma therapy. Vitamin D signaling can be improved by utilizing dietary supplements or by modulating CYP metabolism. A positive association exists between the intake of vitamin D supplements and improved prognosis for melanoma patients. Further investigation is required to determine the function of vitamin D supplementation and specific enzyme targeting in the prevention of melanoma.

Plaque Psoriasis Exacerbation and COVID-19 Vaccination: Assessing the Characteristics of the Flare and the Exposome Parameters

The diverse patient population and widespread vaccination in the COVD-19 era make vaccine-triggered episodes of psoriasis an ideal model of exposome research. This scenario explores the fine balance between protective and exacerbating factors, providing insights into the complex relationship between environmental exposure and psoriasis immunopathogenesis when a trigger appears, such as that of the hyperinflammatory state induced by the COVID-19 vaccine. Analyzing interactions between vaccine-induced phenomena and exposome parameters may provide clinically relevant information important for personalized medicine decision-making. We performed a literature review seeking patients with plaque psoriasis flares or new onset or change in plaque psoriasis into another psoriasis subtype, such as pustular or erythrodermic flare, focusing on the inner and external exposome traits of patients. We identified 71 patients with plaque psoriasis flares, 12 patients with new-onset psoriasis, and 17 with plaque psoriasis subtype change, and assessed the COVID-19 vaccine-induced plaque psoriasis in terms of clinical presentation, post-vaccination flare period and treatment status, as well as inner exposome parameters (genomics, oxidative stress, hormonal impact due to gender, aging, skin color) and external parameters (UV, infectomics). Novel data on psoriasis flares following COVID-19 vaccination are primarily obtained by combining exposome and vaccine-triggered episode features and characteristics and comparing them with similar psoriasis flares unrelated to COVID-19 vaccination.

Natural Compounds in Non-Melanoma Skin Cancer: Prevention and Treatment

The elevated occurrence of non-melanoma skin cancer (NMSC) and the adverse effects associated with available treatments adversely impact the quality of life in multiple dimensions. In connection with this, there is a necessity for alternative approaches characterized by increased tolerance and lower side effects. Natural compounds could be employed due to their safety profile and effectiveness for inflammatory and neoplastic skin diseases. These anti-cancer drugs are often derived from natural sources such as marine, zoonotic, and botanical origins. Natural compounds should exhibit anti-carcinogenic actions through various pathways, influencing apoptosis potentiation, cell proliferation inhibition, and metastasis suppression. This review provides an overview of natural compounds used in cancer chemotherapies, chemoprevention, and promotion of skin regeneration, including polyphenolic compounds, flavonoids, vitamins, alkaloids, terpenoids, isothiocyanates, cannabinoids, carotenoids, and ceramides.

A Panel of Potential Serum Markers Related to Angiogenesis, Antioxidant Defense and Hypoxia for Differentiating Cutaneous Squamous Cell Carcinomas from Actinic Keratoses

Cutaneous squamous cell carcinoma (cSCC) arising from the malignant proliferation of epidermal keratinocytes is the second most common skin cancer. Actinic keratosis (AK), which is considered cSCC in situ, may progress into invasive tumors. Currently, there are no serum markers that can differentiate cSCC from AK. The aim of our study was to assess angiogenesis and oxidative stress in patients with cSCC and patients with AK and find reliable serum markers useful in the diagnosis of cSCC. We have determined the serum levels of a group of proangiogenic factors (MMP-2, MMP-9, VEGF, FGF2), the total antioxidative status/capacity (TAS/TAC), ImAnOx, a marker of oxidative stress, and HIF-1 alpha, an indicator of hypoxia. We have identified higher serum levels of MMP-2. MMP-9, VEGF, FGF2 and HIF-1 alpha and lower levels of ImAnOx in cSCC patients compared to AK patients and controls. There were no statistically significant differences between AK patients and controls. We have found positive correlations between proangiogenic markers and HIF-1 alpha and negative correlations between proangiogenic markers and ImAnOx. Our results suggest that MMP-2, MMP-9, VEGF, FGF2, ImAnOx and HIF-1 may be promising markers for differentiating AK from cSCC, and there is a link between angiogenesis, oxidative stress and hypoxia.

Effectiveness of Narrowband Ultraviolet Light in Chronic Kidney Disease-Associated Pruritus

INTRODUCTION

 Chronic kidney disease-associated pruritus (CKDaP) is a prevalent and challenging symptom in individuals suffering from advanced chronic kidney disease (CKD). Its underlying mechanism remains inadequately understood, leading to a limited array of unsatisfactory therapeutic interventions. Despite various attempts, identifying the most effective treatment remains inconclusive. Nevertheless, there is a growing interest in employing ultraviolet phototherapy, particularly for non-responsive patients, although its efficacy is not definitively established. To investigate the potential benefits of narrowband ultraviolet B (NB-UVB) phototherapy on individuals experiencing CKDaP, we report our experience with NB-UVB light in management of CKDaP in dialysis patients.

MATERIALS AND METHODS

The study group consisted of patients with end-stage chronic kidney disease who underwent hemodialysis. These patients received dermatological consultations and follow-ups for itching. They were all unresponsive to the conventional treatment (emollients and antihistamines). Screening laboratory examinations, including complete blood count, liver function test, thyroid function, electrolytes, and others, were also arranged to exclude systemic etiologies. The main potential pruritogens were dosed: calcium, phosphate, and parathyroid hormone. Itch intensity was evaluated with a numerical rating scale (0-10), based on the worst level of itching in the past two weeks. They had sessions of NB-UVB light (311 nm, TL01) twice per week. After UVB exposure, patients were advised to use topical emollients. A questionnaire was employed to document the extent, intensity, frequency, and sleep disruption experienced to evaluate the efficiency of the treatment, using a scale from 0 to 10.  Results: In a group of 38 patients, the average age of the patients was 56 years (16-80); 63.2% were female and 36.8% were male. Median duration of pruritus was 4.7 years, and that of dialysis was 8.4 years. Pruritus was intermittent and diffuse in most cases, localized to the arteriovenous fistula site in two cases, and exacerbated by heat in all cases. Itch intensity was evaluated with a numerical rating scale (0-10) based on the worst level of itching in the past two weeks and showed a moderate average score (5/10). Xerosis was found in 63%, and scratch lesions such as excoriation in 34%. NB-UVB phototherapy was used twice per week on nonconsecutive days, with protection of the genital area and also the eyes using UVB-blocking goggles. The initial dose was 0.4 J/cm2 and further doses were introduced according to the erythema response until a maximum of 2 J/cm2. No sunburn, hyperpigmentation, or blistering was noted. Emollients were maintained in patients with xerosis. Average number of sessions was 13 (6-24) and reduction of itch intensity was observed starting from the sixth session. Total improvement was obtained at the end of treatment duration except for three patients who required additional sessions. One patient had recurrence one year later.  Conclusion: In conclusion, phototherapy represents a significant advancement in the treatment options for CKD-associated pruritus. Its positive impact on reducing itching and improving the quality of life for many patients is undeniable. However, to fully unlock its potential, ongoing research is needed to optimize dosing, understand relapse mechanisms, and identify the patients who will benefit most from this therapy.

The Association of Vitamin D with Non-Melanoma Skin Cancer Risk: An Umbrella Review of Systematic Reviews and Meta-Analyses

Background and Objectives: Previous studies revealed the anti-angiogenic, antiproliferative, and anti-inflammatory effects of Vitamin D (VitD) on cancer cells. Although this body of evidence supported the correlation of high VitD levels with reduced incidence rates for various malignancies, contradictory results were reported regarding non-melanoma skin cancer (NMSC). The aim of this overview was to summarize the available evidence from the existing pool of systematic reviews and meta-analyses, focusing on VitD serum status, dietary intake, and VitD receptor (VDR) polymorphisms in correlation to NMSC incidence. Materials and Methods: A literature search in electronic databases was conducted from inception to January 2023. The inclusion criteria were systematic reviews and meta-analyses published in peer-reviewed journals, evaluating VitD serum levels, dietary and/or supplementary intake, or VDR gene polymorphisms, and reporting data on NMSC. Results: A total of 10 studies were included in the data analysis models. A positive association between VitD serum levels and NMSC is highlighted. However, dietary/supplementation of VitD does not exhibit a likewise strong linkage to NMSC. Despite the contradictory findings, VDR polymorphisms may play a crucial role in the intricate NMSC pathogenesis. Conclusions: This umbrella review shows that high VitD levels are associated with increased NMSC incidence, potentially due to its direct correlation with increased sun exposure. Further research on VDR polymorphisms is suggested to explore their true effect size on NMSC risk.

Outcomes and Follow-Up Data From Two Skin Cancer Screening Events

This study investigated the outcomes and follow-up behaviors of participants from two free skin cancer screening events in the United States. This survey, with 296 participants and a 31% response rate, gathered information on participant demographics, personal history of skin cancer, knowledge of skin screening practices, and follow-up behaviors. There was a high follow-up rate of 92.3% among individuals recommended for further dermatological consultation, but a low (22%) concordance rate between the preliminary diagnoses from the screening and patient-recalled diagnoses. Additionally, about one-sixth of participants identified limited access to care as a motivation for participating in the screening. The study emphasizes the need to improve awareness about the limitations of free screenings, enhance participant education, and ensure equitable access to skin cancer screening. Future research should focus on factors influencing follow-up behaviors and the development of targeted interventions to increase awareness and access to skin cancer screening.

Patient Perception of Skin Cancer Reduction by Nicotinamide Correlates With Use

Introduction Nicotinamide (Vitamin B3) has been shown to reduce the rate of non-melanoma skin cancers by 23%, yet most patients do not know that this supplement reduces skin cancer. Understanding patient beliefs about skin cancer reduction attributed to nicotinamide is important to appropriately counsel patients on oral supplement use and ultimately to prevent non-melanoma skin cancers. Objective The objective of this study was to determine the association between nicotinamide use and perceived efficacy in skin cancer reduction. Methods Patients who underwent Mohs surgery in 2019 were sent an online survey assessing nicotinamide use, efficacy compared to sunscreen, and perceived skin cancer risk reduction. Results Data from 50 surveys revealed a perceived risk reduction attributed to nicotinamide of 31.2% for basal cell carcinoma (BCC), 30.2% for squamous cell carcinoma (SCC), and 24.3% for melanoma. In the subset of respondents taking nicotinamide, the perceived risk reduction was significantly higher at 41.2% for BCC and 38.3% for SCC (p<0.05) and positively correlated with reported nicotinamide use (p<0.05). The perceived risk reduction of melanoma was not significantly increased in patients taking nicotinamide (31.6%); however, the perceived risk reduction was correlated with nicotinamide use (p<0.05). In addition, 15.6% of respondents believed that nicotinamide was more effective than sunscreen at preventing skin cancer. Conclusion A larger perceived reduction of non-melanoma skin cancers attributed to nicotinamide is associated with increased oral nicotinamide use. Better patient education regarding the reduction of skin cancers with oral nicotinamide will need to be implemented to change patients' perceptions of the value of nicotinamide.

Exploring the Protective Efficacy of Topical Products for Actinic Keratosis Against Ultraviolet-Induced DNA and Protein Damage: An Experimental, Double-Blind Irradiation Study

Introduction Numerous studies have delved into the clinical efficacy of different topical treatments for actinic keratosis (AK). However, our understanding remains limited regarding their capacity to prevent DNA and protein damage caused by ultraviolet radiation (UVR). Objectives The aim of this study was to analyze and compare the preventive capabilities of various AK-targeted products in countering DNA and protein alterations in human biopsies following exposure to experimental UVR. Methods Twelve healthy Caucasian volunteers (six men and six women) aged 18 years and above, with Fitzpatrick skin types II-III, participated in an experimental irradiation study. Six topical products, containing various ingredients (DNA repair enzymes, antioxidants, keratolytic agents, cyclooxygenase inhibitors, and/or sunscreens) were tested. The experimental sites were exposed to UVR at six times the minimal erythema dose for eight consecutive days. Each test product was applied 30 to 45 minutes before irradiation at a standard thickness of 2 mg/cm2. A control site was treated with the vehicle alone, serving as a negative control. The study focused on cyclobutane pyrimidine dimers (CPDs) and protein carbonylation (PC) as molecular markers of UVR-induced DNA and protein damage, respectively. Results The efficacy of different AK-targeted topical products showed substantial variation when applied to normal skin before experimental exposure to UVR. While sunscreens, predictably, played a crucial role, additional ingredients (i.e., DNA repair enzymes and antioxidants) also acted as vital protective agents for both the cellular genome and proteome, shielding them against UVR-induced damage. Conclusion In topical products specifically designed for AK, the strategic integration of DNA repair enzymes and antioxidants, in addition to sunscreens, establishes a critical defense mechanism against the detrimental effects of UVR on cellular DNA and proteins.