title: Comparison of properties of spontaneous and radiation-induced mouse thymic lymphomas: role of Trp53 and radiation.
abstract: Mouse thymic lymphomas are readily induced by radiation and also arise without irradiation when the mice are null in Trp53 functions. In the present study, spontaneous thymic lymphomas in Trp53-/- mice were compared to those arising in irradiated Trp53+/- mice, revealing three features characteristic of the spontaneous lymphomas. (1) Mp53D2, a Trp53 modifier that affects the latent period of radiogenic thymic lymphomas in Trp53+/- mice, had no effect on the development of spontaneous lymphomas. (2) A sex difference in the latency was found. (3) A marked difference was noted in the frequency of allelic loss at the Ikaros gene on chromosome 11, encoding a transcription factor required for normal lymphocyte development and differentiation; 2% in the lymphomas of Trp53-/- mice and 78% in the radiogenic lymphomas of Trp53+/- mice, suggesting that loss of Trp53 may reduce the requirement for the loss of Ikaros for lymphomagenesis. Furthermore, allelic loss analysis on chromosome 19 localized a region that may harbor an unknown tumor suppressor gene. These results suggest intricate steps of lymphomagenesis influenced by the presence or absence of Trp53.
authors.affiliation: Department of Molecular Genetics, Graduate School of Medical and Dental Sciences, Niigata University, Asahimachi 1-757, Niigata 951-8122, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Kubota
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Yoshikai
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Tamura
authors.forename: Yukio
authors.initials: Y
authors.lastname: Mishima
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Aoyagi
authors.forename: Ohtsura
authors.initials: O
authors.lastname: Niwa
authors.forename: Ryo
authors.initials: R
authors.lastname: Kominami
mesh_terms: D000818:Animals; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D008223:Lymphoma / Q000235:genetics / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009381:Neoplasms, Radiation-Induced / Q000235:genetics / Q000378:metabolism*; D011829:Radiation Dosage; D013953:Thymus Neoplasms / Q000235:genetics / Q000378:metabolism*; D016159:Tumor Suppressor Protein p53 / Q000235:genetics* / Q000378:metabolism*; D014916:Whole-Body Irradiation / Q000009:adverse effects
chemical_list: D016159:Tumor Suppressor Protein p53