MP07-66 is a novel FTY720-analog devoid of immunosuppressive effects leads to the reactivation of PP2A, which in turn triggers apoptosis of CLL cells.

CLL cells were incubated with increasing concentrations of MP07-66 (0-16 μM) for 24 and 48 hours and then subject to annexin V–PI flow cytometry. The level of apoptosis reached 50% and 80%, at 24 hours and 48 hours, respectively, at a MP07-66 concentration as high as 16 μM, which paralleled PARP cleavage, a marker of caspase-dependent apoptosis. In addition, the phosphorylation status of PP2A targets, namely Akt, GSK-3, and SHP-1, was negatively affected by the treatment with MP07-66, triggering known downstream events promoting apoptosis, such as Mcl-1 degradation and caspase-3 activation[1].