Cutaneous photochemoprotection by green tea: a brief review.
Alarmingly increasing incidences of skin cancer are being reported from many countries where the majority of the population is Caucasian. According to projected estimates by the American Cancer Society, approximately 1.3 million cases of basal-cell and squamous-cell cancers, grouped together as nonmelanoma skin cancers, are diagnosed annually in the USA alone. It is clear that excessive exposure of the skin to solar radiation, particularly the UVB component, is responsible for these cancers. It is also important to mention here that among all the cancers, skin cancer is believed to be one of the most preventable and curable cancer types. While the surgical therapy for these skin cancers is highly effective, because of their recurrence and many other reasons, these cancers cause significant morbidity to the patients. One way to reduce the occurrence of these cancers is through chemoprevention. For the chemoprevention of photodamage and thus for photocarcinogenesis, we will use the term 'photochemoprotection'. In recent years, the naturally occurring compounds, especially the antioxidants, present in the common diet and beverages consumed by the human population have gained considerable attention as chemopreventive agents for potential human benefit. Many such agents have found a place in skin care products. Green tea, rich in polyphenolic antioxidants, is gaining increasing attention as a supplement in skin care products. In this short review, we will discuss the chemopreventive potential of green tea polyphenols against skin cancer, especially photocarcinogenesis. We advocate that the use of skin care products supplemented with agents such as green tea in conjunction with the use of sunscreens and educational efforts may be an effective strategy for reducing UV-induced photodamage and skin cancer in humans.