ZAP70 in chronic lymphocytic leukaemia

The protein tyrosine kinase zeta-chain associated protein kinase (ZAP70), normally expressed in T cells and a subset of B cells, is solely expressed in poor prognosis chronic lymphocytic leukaemia and implicated in enhanced B cell receptor signalling. As a result, the expression of this protein provides an ideal prognostic marker for the disease. A previous study has shown differential CpG methylation of a 5' region of ZAP70 in leukaemic lymphoid cells, although no further epigenetic studies have been reported. Further investigation into the expression of ZAP70 may therefore provide targets for therapies.