Editing Azathioprine (section)

====Skin cancers====
In transplant patients, [[skin cancer]] is 50 to 250 times more common than in the general population, and between 60 and 90% of patients are affected 20 years after transplantation. The use of immunosuppressive medication including azathioprine in organ transplantation has been linked to increased rates of developing skin cancer.<ref name="bbcsb">{{cite web |url=http://news.bbc.co.uk/2/hi/health/4248356.stm |title=Skin cancer alert for organ drug |date=September 15, 2005 |website=[[BBC Online]] |publisher=[[BBC News]] |access-date=June 10, 2012 |url-status=live |archive-url=https://web.archive.org/web/20121014205054/http://news.bbc.co.uk/2/hi/health/4248356.stm |archive-date=October 14, 2012 }}</ref> Azathioprine causes the accumulation of [[6-thioguanine]] (6-TG) in patients' DNA, which might trigger cancer when the patient is later exposed to [[ultraviolet light]]. Patients taking azathioprine were found to be abnormally sensitive to UVA light.<ref>{{cite journal | vauthors = O'Donovan P, Perrett CM, Zhang X, Montaner B, Xu YZ, Harwood CA, McGregor JM, Walker SL, Hanaoka F, Karran P | title = Azathioprine and UVA light generate mutagenic oxidative DNA damage | journal = Science | volume = 309 | issue = 5742 | pages = 1871–1874 | date = September 2005 | pmid = 16166520 | pmc = 2426755 | doi = 10.1126/science.1114233 | bibcode = 2005Sci...309.1871O }}</ref>