Figure 5.

Depletion or re-expression of cyclin D1 affects proton RBE in TNBC cells. (A) The knockdown of cyclin D1 via siRNA in Hs578T cells. (B) Depletion of cyclin D1 increased proton RBE in the Hs578T cell line, as judged by a clonogenic survival assay. Data are presented as the mean ± SEM of two independent experiments and the differences are evaluated by a two-way ANOVA; ** p < 0.01; *** p < 0.001. Dashed lines indicate SF = 0.1. (C) Western blot analysis confirmed transient overexpression of HA-tagged cyclin D1 in BT-549 cells. Ectopic expression of cyclin D1 did not affect expression of other genes, such as RB1 and E2F1. (D) Overexpression of cyclin D1 in BT-549 cells decreased RBE₁₀ from 1.40 to 1.14. Data are presented as the mean ± SEM of two independent experiments and the differences are evaluated by a two-way ANOVA; *** p < 0.001.