Given that ALK+ ALCL tumour cells exhibit high levels of apoptosis [28–30] and the observed correlation between GzB expression and apoptosis rate in nasal-type NK/T lymphomas [12] and prostate cancer cell lines [18], we decided to investigate whether GzB expression might sensitize ALK+ ALCL cells to apoptosis. The gene discussed is ALK; the disease is anaplastic large cell lymphoma.