Skin cancer chemoprevention

Mukhtar H, Agarwal R (1996) Skin cancer chemoprevention. J Investig Dermatol Symp Proc 1 209-214... 

Ahmad N, Gab H, Javed S, Agarwal R. Skin cancer chemopreventive effects of a flavonoid antioxidant silymarin are mediated via impairment of receptor tyrosine kinase signaling and perturbation in cell cycle progression. Biochem Biophys Res Commiin 1998 247 294-301. 

Currently, 13-cis-retinoic acid is the most studied chemopreventive agent that decreases the incidence of second primary tumors in patients with head-and-neck cancer, reverses premalignant lesions, and reduces appearance of nonmelanoma skin cancer in patients with xeroderma pigmentosum. Unfortunately, this vitamin A derivative has a significant clinical toxicity, which limits its utility in a practice setting. 

Bode, A.M. and Dong, Z. 2000. Signal transduction pathways targets for chemoprevention of skin cancer. Lancet Oncol 1 181-188. Review. 

In addition to their possible prooxidant activity (see above) polyphenols and flavonoids may influence cancer cells via their antioxidant properties. Recently, Jang et al. [219] studied cancer chemopreventive activity of resveratrol, a natural polyphenolic compound derived from grapes (Chapter 29). These authors showed that resveratrol inhibited the development of preneoplastic lesions in carcinogen-treated mouse mammary glands in culture and inhibited tumorigenesis in a mouse skin cancer model. Flavonoids silymarin and silibinin also exhibited antitumor-promoting effects at the stage I tumor promotion in mouse skin [220] and manifested antiproliferative effects in rat prostate cancer cells [221]. 

Aziz MFI, Reagan-Shaw S, Wu J, Longley BJ, Ahmad N. 2005. Chemoprevention of skin cancer by grape constituent resveratrol Relevance to human disease FASEB J 19 1193-1195. 

Orengo, I.F., Gerguis, J., Phillips, R., Guevara, A., Lewis, A.T., and Black, H.S., Celecoxib, a cyclooxygenase 2 inhibitor as a potential chemopreventive to UV-induced skin cancer a study in the hairless mouse model, Arch. Dermatol., 138, 751, 2002. 

Carotenoids have beneficial effects in cancer chemoprevention (Astrog, 1997). Fucoxanthin, one of the the major carotenoids in brown algae, is known to exhibit antitumor activity against human neuroblastoma GOTO cells (Okuzumi et al., 1990). Inhibitory effects on mouse duodenum and on skin carcinogenesis have also been reported (Okuzumi et al., 1993 Satomi et al., 1996). 

Azuine MA, Tokuda H, Takayasu J, et al. (2004) Cancer chemopreventive effect of phenothiazines and related tri-heterocyclic analogues in the 12-O-tetradecanoyl-phorbol-13-acetate promoted Epstein-Barr virus early antigen activation and the mouse skin two-stage carcinogenesis models. Pharmacology Research 49 161-169. 

DiGiovanna, J.J. (2001) Retinoid chemoprevention in patients at high risk for skin cancer. Medical and Pediatric Oncology, 36, 564—567. 

So far, no potential cancer chemopreventive agent constituent from a Hernandia species has been subjected to biological follow up after the initial in vitro investigation, e.g., by using a mouse mammary organ culture assay [75] or a two-stage mouse skin carcinogenesis test [86]. 

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