As illustrated by a patient biopsied at BL and post-progression, more intense staining of cyclin E1 and cyclin E2 was seen in the PD tumor cells with higher Ki67 and higher phosphorylated retinoblastoma protein levels compared with cells from BL (Additional file 6: Fig. S10a), consistent with the corresponding gene expression patterns in the cohort and in paired BL and PD tumors (Additional file 6: Fig. S10b, 10c). This evidence concerns the gene MKI67 and Burkitt lymphoma.