CD70 and cancer: The implications of these findings on anti-tumour immunity in OGJ patients are not clear as the role of CD27 signalling in cancer remains conflicting, CD27 signalling either leads to improved T cell function or to T cell dysfunction, likely dependent upon the amount, duration, and timing of the expression of the CD27 ligand (CD70) (Nolte et al. 2009; Matter et al. 2006), offering a likely explanation to the conflicting evidence for CD27–CD70 interaction in promoting or inhibiting anti-cancer immunity.