Using a Cox-2 conditional knockout model (Ptgs2flox/flox) developed by the Herschman group61, we have also recently determined the role of cell-type-specific Cox-2 expression in Krt15-CrePR+ tumor-prone hair follicle stem cells expressing KrasG12D together with a p53 loss of function mutation62. The gene discussed is TP53; the disease is neoplasm.