USP6 and neoplasm: Flow cytometric analysis of tumor digests demonstrated that in RAG2−/− mice, USP6 did not affect the overall abundance of immune cells (CD45+) or tumor-infiltrating NK cells (TINK; defined as NK1.1+NKp46+), or NK subpopulations (as defined by CD27/CD11b levels; refs. 25–27; Supplementary Fig. S2A and S2B).