Phytochemicals for the Prevention of Photocarcinogenesis

Abstract

Ultraviolet (UV) exposure has an array of damaging effects and is the main cause of skin cancer in humans. Non-melanoma skin cancer (NMSC), including basal cell carcinoma and squamous cell carcinoma, is the most common type of cancer. Incidence of NMSC has increased due to greater UV radiation, increased life expectancy, and other changes in lifestyle; the annual cost of skin cancer treatment in the United States has increased concurrently to around eight billion dollars. Because of these trends, novel approaches to skin cancer prevention have become an important area of research to decrease skin cancer morbidity and defray the costs associated with treatment. Chemoprevention aims to prevent or delay the development of skin cancer through the use of phytochemicals. Use of phytochemicals as chemopreventive agents has gained attention due to their low toxicity and anti-carcinogenic properties. Phytochemicals also exhibit antioxidant, anti-inflammatory, and anti-proliferative effects which support their use as chemopreventive agents, particularly for skin cancer. Preclinical and human studies have shown that phytochemicals decrease UV-induced skin damage and photocarcinogenesis. In this review article, we discuss the selected phytochemicals that may prevent or delay UV-induced carcinogenesis and highlights their potential use for skin protection.

Rosemary Diterpenes and Flavanone Aglycones Provide Improved Genoprotection against UV-Induced DNA Damage in a Human Skin Cell Model

“…Intracellular ROS also act as inflammatory mediators through the induction of the expression of proinflammatory enzymes and cytokines such as interleukin (IL)-1β, IL-6, IL-9, and cyclooxygenase-2 (COX2) [19]. In fact, the overproduction of ROS mediates the activation of NF-κB transcription factors, which are of central importance in inflammation [44].…”

“…Numerous flavonoids, such as apigenin, genistein, and quercetin, protect against UV-induced oxidative stress [15][16][17]. Furthermore, plant terpenoids also act as strong antioxidant compounds, and both polyphenols (especially flavonoids and isoflavones) and terpenoids display anti-inflammatory and antiphotocarcinogenic effects by modulating cell signaling pathways and regulating the cell cycle [18,19]. Several botanical extracts have exhibited a protective effect against UV radiation, such as Aloe vera, Punica granatum, and Silybum marianum [20][21][22].…”

Ultraviolet A protective potential of plant extracts and phytochemicals

“…21 ). Several reports documented the ability of SM and SB to reduce chemically-and UVB-stimulated skin damage, including carcinogenesis 21,22 .…”

“…Pomegranate fruit extract exhibits antioxidant and anti-inflammatory properties. Many in vitro and in vivo studies demonstrated a photoprotective effect of pomegranate against UVB radiation 22 .…”

Epigenetics of skin cancer: Interventions by selected bioactive phytochemicals

“…Excessive exposure to ultraviolet (UV) radiation present in the sunlight is the major cause of skin cancer . UV radiation produces harmful effect to the skin through many ways including (i) DNA damage, (ii) production of reactive oxygen species (ROS), (iii) activation of inflammatory signaling pathways . Other causes of skin cancer include exposure to chemicals, genetic vulnerability, and the viruses such as human papillomavirus (HPV).…”