MOL4070LTR infection accelerates leukemic transformation in CALM-AF10 mice. (A) Survival of MOL4070LTR-infected CALM-AF10 mice (■, N = 45), MOL4070LTR-infected WT (○, n = 31), and noninfected CALM-AF10 transgenic mice (●, N = 20). *P < .001, comparing infected CALM-AF10 with noninfected CALM-AF10, or infected CALM-AF10 with WT mice using a log-rank test. (B) Distribution of leukemia by immunophenotype in WT and CALM-AF10 mice infected with MOL4070LTR retrovirus. Note the predominance of B-cell and myeloid (AML) tumors, as well as the lack of pre-T LBL, in the CALM-AF10 mice compared with the WT control mice. (C) Retroviral integration analysis. Southern blot of EcoRI-digested DNA extracted from leukemic spleens hybridized to a viral env probe. Mouse identification numbers are indicated; C indicates germline control tissue; size standards are given in kilobases. The proviral genome is 8.7 kb and does not contain an EcoRI site.