CXCR2 and melanoma: To evaluate the role of CXCR2 in BrafV600E/Pten−/− melanoma tumorigenesis, we crossed C57BL/6 Tyr-CreER + ::BrafV600E/Ptenfl/fl::mT/mG:: mice (Braf/Pten) [23] with C57BL/6 mice carrying a Cxcr2fl/fl allele [24] to produce Tyr-CreER + ::BrafV600E/Ptenfl/fl::mT/mG::Cxcr2−/− (Braf/Pten/Cxcr2−/−) and Tyr-CreER + ::BrafV600E/Ptenfl/fl::mT/mG::Cxcr2WT (Braf/Pten/Cxcr2WT) littermates.