Importantly, increased PPM1D expression at diagnosis was itself associated with a poorer prognosis in MCL patients (median overall survival of 3.9 years and 1.4 years for cases in the lowest and highest PPM1D expression tertiles, respectively; P = 0.0047; Bonferroni-corrected threshold 0.0167; Figure 1D). This evidence concerns the gene PPM1D and mantle cell lymphoma.