Pim-2 transgene induces lymphoid tumors, exhibiting potent synergy with c-myc.

Evidence from proviral tagging experiments has suggested that pim-2 is similar in oncogenic behavior to its well characterized relative pim-1. While the basal expression in tissues differs, both genes are highly expressed in mitogenically stimulated hematopoietic cells and their transcription is induced in response to the same cytokines. Expression of a pim-2 transgene in lymphoid cells predisposed mice to T-cell lymphomas like those promoted by pim-1 transgenes. Moreover, strong collaboration with an E mu-myc transgene was manifested as pre-B cell leukemia in neonate bi-transgenic animals. Remarkably, this collaboration was attenuated but not prevented by X-inactivation of one of the transgenes. The addition of pim-2 to the fold increases the prominence of the pim proto-oncogene family in tumorigenesis.