The use of a sunscreen containing DNA-photolyase in the treatment of patients with field cancerization and multiple actinic keratoses: a case-series.

Cutaneous field cancerization (CFC) is associated witha high-risk of developing cutaneous squamous cellcarcinoma (cSCC). It manifests as actinic keratoses(AK) as one of the few macroscopic alterations in CFCpatients. A prospective, single-arm, case-series wasperformed to evaluate the utility of a novel sunscreencontaining DNA-photolyase for treatment of CFCin nine subjects (mean age 70.6 years, male: femaleratio 5:4). The cream was applied topically twicedaily on CFC/AK areas and patients were followedup for three months, with no other treatments. Theprimary outcome was the overall response rate (ORR),categorized as complete response (CR, completeresolution of AKs), partial response (PR, reduction inthe number of AKs), and no-response (NR, similar/increase in number of AKs). A 100% PR was observed.All subjects displayed at minimum, a 50% reductionin their lesion number and most patients experiencedalmost CR. Evaluation of AK numbers revealed anabsolute count reduction of 76.6% in the number oflesions, with the mean number of lesions reducedfrom 13.4 to 3.1 (p < 0.0001). No adverse events werereported. Patients with CFC may benefit from noveltopical applications containing DNA-photolyase,at minimum, as complementary therapy for themanagement of CFC disease. We propose a newconcept called "active photoprotection" because of itsdual mechanism involving therapy and protection.

Vitamin D axis and its role in skin carcinogenesis: a comprehensive review

Vitamin D (VD) is a secosteroid hormone that is mainly synthesized in the skin upon exposure to UVB radiation. VD is widely known for its role in calcium metabolism; however, multiple endocrine, paracrine and autocrine functions of VD have been described, including a prominent role on carcinogenesis. In recent years, multiple associations between VD deficiency and different types of cancer have been described, supported by evidence of anti-proliferative, anti-angiogenic, pro-apoptotic, cell-differentiating and anti-invasive effects of this hormone. An immunomodulatory role of VD associated to cancer microenvironment has also been suggested. Regarding skin cancer, it has been shown that VD inhibits tumor development in basal cell carcinoma, squamous cell carcinoma, and melanoma in vitro. Some studies have suggested that lower VD levels may be a risk factor for skin cancer, while others have shown the opposite; there is also preliminary evidence on the role of VD supplementation for the prevention of melanoma in vivo. In this review, we explore the mechanisms of VD effects on carcinogenesis and the available scientific evidence of the interplay between VD and the genesis of both non-melanoma and melanoma skin cancer. (AU)