Pokemon/LRF/ZBTB7A/FBI1 [BC17-2.9F]

Pokemon (LRF/ZBTB7A/FBI1) is a member of the POK family of transcriptional repressors, and is expressed in hematopoietic stem cells, T and B lymphocytes, macrophages, and erythroid cells. This protein is also highly expressed in human non-Hodgkin’s lymphoma tissues and diffuse large B-cell lymphomas, demonstrating its prominent role in oncogenic transformation. Studies have demonstrated that LRF is also involved in B cell lineage commitment and development by opposing Notch signaling. Moreover, LRF is critical for erythroid terminal differentiation in the bone marrow by inhibiting Bim-mediated apoptosis. Finally, LRF interacts with Bcl-6 in germinal center B cells. It functions as a transcriptional repressor of the p19 arf p53, and RB tumor suppressor genes and works in concert with oncogenes and other proteins associated with the promotion of cell growth. Pokemon overexpression has been shown to cause activation of membrane type 1-matrix metalloproteinase which is associated with adverse outcome in ovarian cancers and increased drug resistance. These properties are thought to impart its role in oncogenesis. In this context, Pokemon is regarded as a marker of aggressive tumors and may thus serve as a useful marker of poor prognosis in cancers. It is also being reviewed as a target for inhibiting oncogenesis.