In addition to their endogenous anti-tumor role, CD27+ IFNγ-producing γδ T cells control tumor growth after ex vivo expansion and adoptive cell transfer into tumor-bearing mice (Beck et al, 2010; Cao et al, 2016; He et al, 2010; Liu et al, 2008; Street et al, 2004), mirroring the outcomes of experiments using human Vγ9Vδ2+ or Vδ1+ cells (Silva-Santos et al, 2019). Here, CD27 is linked to neoplasm.