TRIM33 and leukemia: We have also shown that while the BTS derivatives that exhibit this cytotoxic activity are able to inhibit a NOX activity of the plasma membrane of leukaemia CCRF-CEM cells, those that lack cytotoxic activity also lack this inhibitory effect (Alonso et al, 2001), thus suggesting that ECTO-NOX proteins could provide a molecular target for the induction of ROS production by BTS derivatives.