IL2RG and neoplasm: This phenotype was recapitulated in LK-2 tumors that developed in Rag2–/–Il2rg–/–Cd47–/– recipient mice, where a significantly higher proportion of parental LK-2 than CALB1-deficient LK-2 2B7 tumor cells stained positive for p63, a marker for squamous epithelial differentiation encoded by TP63 (Figure 3B).