Fig. 3.
Sensitizing tumor cells to radiation increases local control of primary sarcomas after radiation therapy. (A) Clonogenic survival of primary sarcoma cell lines from P7KPloxPAtmFL/+ and P7KPloxPAtmFL/FL mice (n=3 independent cells lines per genotype). Two-way ANOVA for genotype and dose interaction, P<0.05, followed by Bonferroni’s post hoc tests for pairwise comparisons between genotypes after 2 and 4 Gy, P<0.05. (B) Sarcoma growth curves and (C) Kaplan-Meier plot of local sarcoma control defined as the absence of tumor volume tripling for primary sarcomas generated by intramuscular 4-hydroxy-tamoxifen injection into P7KPloxPAtmFL/+ and P7KPloxPAtmFL/FL mice after irradiation with 50 Gy (n=13 mice per group). Several mice were euthanized prior to sarcoma tripling because of the development of second sarcomas at other locations in the body, presumably from systemic tamoxifen-mediated Cre recombination. These mice were scored as locally controlled until the time point of second tumor formation. Log rank test, P<0.05. Asterisks represent a statistically significant difference between the indicated groups.