Immunostainings of cyclin E and p27 in normal lymphoid tissues and malignant lymphomas. (A) Cyclin E staining in an indolent lymphoma showing both nuclear and cytoplasmic reactivity. (B) p27 staining of a reactive follicle in a tonsil. Notice the staining pattern in the dark and light zone. (C) p27 staining of a malignant follicular in an FL lymphoma. The staining pattern is representative for indolent lymphomas. (D) CLL with p27⁻pseudofollicles. (E) Large cell lymphoma with p27⁻blastic cells and occasional positive small lymphocytes (S-phase fraction = 11.5%). (F) Large cell lymphoma with p27⁺(S-phase fraction = 3.4%).