Fig. 2.

FGFR4^V550E p53^−/− myoblasts engrafted into murine skeletal muscle generate a high incidence of tumors. a Murine model schema depicts p53^−/− myoblast harvest, transduction, injection into p53^+/− host hind limbs, and tumor analysis. b A murine tumor following M25. FGFR4^V550E injection into the right hind limb. c Kaplan–Meier curves depicting tumor-free survival illustrate statistically significant differences among tumor models expressing different FGFR4 constructs. M25.EV did not generate tumors. M25.FGFR4^V550E- and M25. FGFR4^wt-injected mice formed tumors with statistically different penetrance and latencies compared to each other and to the M25.EV control cohort. Two mice injected with M25.FGFR4^N535K developed tumors, one encoded FGFR4^N535K while the second tumor was shown to encode FGFR4^wt (asterisk). d Amplicons from tumor tissue were sequenced and shown to encode the correct FGFR4 transgenes. M25F1 represents tumor tissue from the M25.FGFR4^wt cohort, M25FN23 from M25.FGFR4^N535K, and M25FV24 from M25. FGFR4^V550E. e Protein expression was confirmed in tumor lysates using immunoblot and human FGFR4-specific antibodies. Parental myoblasts, Myo25, did not express human FGFR4 proteins