It is well-known to be deregulated in some types of human tumors [51]; Ras mutations are found in 45% of colon carcinomas and 90% of pancreatic cancers; Raf mutations are found in two-thirds of melanomas, where TSLCs have been enriched by sorting for CD133 protein expression. The gene discussed is PROM1; the disease is familial pancreatic carcinoma.