CXCR1 and neoplasm: To pin the lineages that express CXCR1 and CXCR2 in lungs colonized by NRASMUT tumor cells, we intercrossed hematopoietic Cre‐driver (Vav.Cre; Ogilvy et al, 1998) to Cre‐reporter (mT/mG; Muzumdar et al, 2007) mice and pulsed offsprings with s.c. NRASMUT tumor cells to generate a lung metastasis model that features mG+ hematopoietic, mT+ non‐hematopoietic, and non‐fluorescent tumor cells.