The role of drugs and selected dietary factors in cutaneous squamous cell carcinogenesis.

Cutaneous squamous cell carcinoma represents the second most common non-melanoma skin cancer and its incidence increases worldwide. This review provides an overview of selected exogenous risk factors for cutaneous squamous cell carcinoma, which include drugs (azathioprine, calcineurin inhibitors, hydrochlorothiazide, angiotensin-converting-enzyme inhibitors) and few dietary factors (fat meet, whole milk products, arsenic) to better understand squamous skin cancer etiopathogenesis. Ingredients such as leafy vegetables, nuts, fish, caffeine, niacin are preventive factors for cutaneous squamous cell cancer. The heart transplant recipients have an increased risk of squamous cell carcinoma development than kidney or liver transplant ones and switching photosensitizing azathioprine to mycophenolate mofetil can reduce the incidence of cutaneous squamous cell carcinoma. The great attention should be paid to early change of cardiac photosensitizing antihypertensive drugs to non-photosensitizing ones among patients with a history of prior skin cancers and among organ transplant recipients. Based on current knowledge that ultra-violet radiation is the main risk factor for squamous cell carcinoma development, promotion of the skin self-examination, photoprotection, tanning bed avoidance and early skin cancer diagnosis is important for this tumour prevention.

Evaluation of keratin biomaterial containing silver nanoparticles as a potential wound dressing in full-thickness skin wound model in diabetic mice.

Keratin is a cytoskeletal scaffolding protein essential for wound healing and tissue recovery. The aim of the study was to evaluate the potential role of insoluble fur keratin-derived powder containing silver nanoparticles (FKDP-AgNP) in the allogenic full-thickness surgical skin wound model in diabetic mice. The scanning electron microscopy image evidenced that the keratin surface is covered by a single layer of silver nanoparticles. Data obtained from dynamic light scattering and micellar electrokinetic chromatography showed three fractions of silver nanoparticles with an average diameter of 130, 22.5, and 5 nm. Microbiologic results revealed that the designed insoluble FKDP-AgNP dressing to some extent inhibit the growth of Escherichia coli and Staphylococcus aureus. In vitro assays showed that the FKDP-AgNP dressing did not inhibit fibroblast growth or induce hemolysis. In vivo studies using a diabetic mice model confirmed biocompatible properties of the insoluble keratin dressings. FKDP-AgNP significantly accelerated wound closure and epithelization at Days 5 and 8 (p < .05) when compared with controls. Histological examination of the inflammatory response documented that FKDP-AgNP-treated wounds contained predominantly macrophages, whereas their untreated variants showed mixed cell infiltrates rich in neutrophils. Wound inflammatory response based on macrophages favors tissue remodeling and healing. In conclusion, the investigated FKDP-AgNP dressing consisting of an insoluble fraction of keratin, which is biocompatible, significantly accelerated wound healing in a diabetic mouse model.

The effect of wool hydrolysates on squamous cell carcinoma cells in vitro. Possible implications for cancer treatment.

Squamous cell carcinoma of the skin is the second most common cutaneous malignancy. Despite various available treatment methods and advances in noninvasive diagnostic techniques, the incidence of metastatic cutaneous squamous cell carcinoma is rising. Deficiency in effective preventive or treatment methods of transformed keratinocytes leads to necessity of searching for new anticancer agents. The present study aims to evaluate the possibility of using wool hydrolysates as such agents. Commercially available compounds such as 5-fluorouracil, ingenol mebutate, diclofenac sodium salt were also used in this study. The process of wool degradation was based on chemical pre-activation and enzymatic digestion of wool. The effect of mentioned compounds on cell viability of squamous carcinoma cell line and healthy keratinocytes was evaluated. The obtained data show a significantly stronger effect of selected wool hydrolysates compared to commercial compounds (p<0.05) on viability of cells. The wool hydrolysates decreased squamous cell carcinoma cells viability by up to 67% comparing to untreated cells. These results indicate bioactive properties of wool hydrolysates, which affect the viability of squamous carcinoma cells and decrease their number. We hypothesize that these agents may be used topically for treatment of transformed keratinocytes in actinic keratosis and invasive squamous skin cancer in humans.