Compound activates anti-cancer gene to fight skin cancer
re-activates the body's own defence mechanisms, according to
scientists, who suggest the molecule may one day be incorporated
into sun care products.
The molecule, CP-31398, appears to restore the body's own tumour fighting potential that is often damaged by UV radiation, and other carcinogenic agents. When applied to the skin of mice the number and volume of skin cancers decreased, say scientists led by Xiuwei Tang from New York, although more research is needed before the finding can be translated into humans. CP-31398 helps prevent skin cancer in mice The target of CP-31398 appears to be the p53 gene - known as a tumour suppressor gene - mutations in which are found in over half of all human cancers, according to the authors. The gene is known to affect functions of the cell cycle and apoptosis (programmed cell death). When the gene is damaged such functions no longer work as they should; this can lead to uncontrolled cell proliferation, problems with cell apoptosis and consequently cancer. When the CP-31398 was applied to mouse skin, which was then exposed to UV radiation, the researchers noted a significant drop in both the number and volume of skin cancers. The molecule was applied topically to 25 mice twice weekly, 30 minutes before the mice were exposed to UV radiation. These were compared to 25 control mice, who received no treatment and no UV radiation, 25 who received radiation and no treatment, and 25 who received radiation and the vehicle. After 35 weeks the mice who had received the treatment had seven tumours on average whereas the mice receiving the vehicle without the molecule had an average of 16, illustrating that CP-31398 had a preventative effect on the development of UV induced skin cancers in mice. Furthermore, the tumours on the treated mice were significantly smaller than those on the untreated mice, according to the team. CP-31398 could have therapeutic benefits In addition the molecule was applied to mice already suffering from UV induced skin cancers, to identify whether or not the molecule had therapeutic benefits. The team applied CP-31398 to the skin of mice for 40 weeks. Those treated with the molecule showed a decrease in the number and volume of tumours, whereas untreated mice showed an increase, according to Tang and the team. CP-31398 in sun care products? Wafik El-Deiry, from the Univeristy of Pensylvania, writes in his comment in the same journal: "the study suggests that CP-31398 topical application may be active in skin cancer prevention following UV light exposure and may provide an effective therapy after cancer development." He suggests that the molecule could be incorporated into sun care products in order to help prevent tumour formation, although he states that further studies are necessary before it can be applied to humans. Previous research suggests that CP-31398 may upregulate the expression of wild type p53, according to El-Deiry who suggests more research is needed into what effect this may have on humans. Furthermore, he suggests that further research should examine the molecule's therapeutic effects in the treatment of other types of cancers. El-Deiry specifically highlights Li-Fraumeni syndrome - a rare hereditary condition in which sufferers possess a mutation in p53 gene that greatly increases their risk of developing cancers. Source: The Journal of Clinical Investigation Volume 117, Number 12, pages 3753-3764 and 3658-3660 CP-31398 restores mutant p53 tumor suppressor function and inhibits UVB-induced skin carcinogenesis Xiuwei Tang, Yucui Zhu, Lydia Han, Arianna L. Kim, Levy Kopelovich, David R. Bickers, and Mohammad Athar Targeting mutant p53 shows promise for sunscreens and skin cancer Wafik S. El-Deiry
