Polyphenols Epigenetic Effects on Skin Cancer Prevention
Introduction. Skin cancer is the leading cancer diagnosed each year in the US.1,5 It has taken a toll on US economy costing $8.1 billion dollars in the US for skin cancer treatment.1,5 There is a number of risk factors that increasing one’s susceptibility for skin cancer: phenotypic markers like lighter skin tone, exposure to tar and sunlight, frequency of skin tanning, and socioeconomic factors.2 Polyphenols is a promising chemical for prevention of skin cancer especially polyphenols found in green tea.4 Methods In a study conducted, melanoma cells were treated with various concentrations of green tea polyphenols.4 Then their cell viability and colony formation were assayed using petri dishes.4 In another experiment, green tea polyphenols were assessed based on their histone deacetylation and acetylation activity using histone deacetylation assay and histone acetylation activity assay, respectively.4 Western blot was also used for that assessment. Following, that the concentration of tumor suppressor genes were assessed using western blot.4 Results With increasing concentrations of green tea polyphenols, melanoma cell viability and colony formation decreased.4 In addition to that, histone deacetylation activity decreased while histone acetylation activity increased with increasing green tea polyphenols. 4 Also, with increasing green tea polyphenol activity, oncogenic protein expression decreased while tumor suppressor increased.4 Conclusion Green tea polyphenols promotes acetylation of histones while decreasing histone deacetylation activity in melanoma cells.4 That thus increases expression of tumor suppressor genes when the histone is more acetylated and more open for expression. 4This altogether decreases the viability of melanoma cells which explains the decrease in cell viability of melanoma cells with increasing green tea polyphenol concentrations.4 Although, green tea polyphenols seemed promising in these results in the prevention of melanoma progression.4 Green tea polyphenols bioavailability through diet is very limited by the time it gets to the screen.3 Green tea polyphenols may be effective in melanoma prevention in combination with other anti-cancer drugs.3
- Apalla Z, Nashan D, Weller RB, Castellsague X. Skin cancer: epidemiology, disease burden, pathophysiology, diagnosis, and therapeautic approaches. Dematol Ther. 2017; 7(Suppl 1): 5-19. doi: 10.1007/s13555-016-0165-y
- Gordon R. Skin cancer: an overview of epidemiology and risk factors. Semin Oncol Nurs. 2013; 29(3):160-9. doi: 10.1016/j.soncn.2013.06.0022
- Mojzer EB, Hrncic MK, Skerget M, Knez Z, Bren U. Polyphenols: extraction methods, antioxidative action,bioavailability and anticarcinogenic effects. Molecules. 2016; 21(7): 901.
- Prasad R, Katiyar SK. Polyphenols from green tea inhibit the growth of melanoma cells through inhibition of class I histone deacetylases and induction of DNA damage. Genes Cancer. 2015;6:49-61.
- Sharma P, Montes De Oca MK, Alkeswani AR, McClees SF, Das T, Elmets CA, et al. Tea polyphenols for the prevention of UVB-induced skin cancer. Photodermatology, Photoimmunology & Photomedicine. 2017; 34(1):50-59. doi: 1.1111/phpp.12345 (in Pathology)