Mechanism of Action of Flavonoids in Prevention of Inflammation- Associated Skin Cancer

Abstract

Skin cancer in humans represents about 30% of all new cancers and is by far the most common malignancy in the Caucasian population. Exposure to radiations especially ultraviolet-B (UV-B) radiation is the major cause for development of skin cancers along with other chemical or biological factors. The growing incidence rates of skin cancer around the world, demand the need for new treatment options. Understanding the etiology and pathogenesis of skin cancer is therefore crucial for developing an effective drug against this prevailing disease. Medicinal plants are rich with numerous secondary metabolites such as flavonoids, which are now known to treat various chronic diseases, including inflammations and cancers. Flavonoids are sub-classified in to flavones, flavonols, iosflavones, flavanones, flavanols and anthocyanidins. They act on different targets including scavenging reactive oxygen species (ROS), regulation of the cell cycle, and initiation of DNA repair mechanisms, apoptotic induction and inhibition of metastasis. Innumerable evidence suggested that an increased consumption of flavonoid-rich fruits and vegetables rendered DNA protection to normal skin exposed to carcinogens such as UV-B radiation. Flavonoids also showed the potential to induce cell death mechanisms in melanoma, the most dreadful form of skin cancer. This comprehensive review presents flavonoids and their mechanism of action in relation to inflammation and skin cancer management.

The Bioavailability, Transport, and Bioactivity of Dietary Flavonoids: A Review from a Historical Perspective

“…Flavonoid actions on Wnt regulation have led some to suggest they may have a therapeutic role in the treatment of colorectal cancer (Amado et al., ). Various mechanisms have been reported based on cell culture studies (Fernando, Rupasinghe & Hoskins, ; George et al., ; George, Dellaire, & Rupasinghe, ; Giampieri et al., ; Joven et al., ; Khan et al., ; Li & Schluesener, ; Zhou et al., ), however, many of these studies are at high concentrations and use unmetabolized flavonoids.…”

Nicotinamide for skin cancer chemoprevention

“…Botanical agents such as the carotenoid antioxidant lycopene can reduce sensitivity to UV‐induced erythema. Leucotomos extract and flavonoids also reduce UV‐induced immune suppression, which plays a key promotional role in skin carcinogenesis . As yet there is no evidence of these agents’ ability to reduce skin cancer incidence in humans.…”

Comparative Analysis of the Interaction between Different Flavonoids and PDIA3

“…They can act by different targets including the regulation of cell signalling and the cell cycle, free radical scavenging, inhibition of angiogenesis, initiation of DNA repair mechanisms, apoptotic induction, and inhibition of metastasis. By affecting such pathways flavonoids have the ability to control cell proliferation and survival and to exhibit antiproliferative and antimutagenic properties and a remarkable anti-inflammatory activity [26–29]. …”