PER2 and B-cell non-Hodgkin lymphoma: For instance, epigenetic changes of the BMAL1 promoter were described in both B cell lymphoma and acute lymphocytic and myeloid leukemia [15], while PER2 was found downregulated in lymphoma and acute myeloid leukemia patients, with PER2 overexpression leading to cell cycle arrest and loss of clonogenicity [16].