Fig. 2.

TRC105 induces transient DNA damage and repression of SIRT1 induction. 22Rv1 were pre-treated with IgG or TRC105 24 h prior to irradiation with 4 Gy. a γ-H2AX or 53BP1 were immunolocalized at 4 and 24 h post irradiation. Foci per nuclei were quantified (n = 100). Representative images are shown for γ-H2AX (green) and 53BP1 (green) foci, nuclear counterstained with DAPI (blue). b Comet assay was performed 30 min and 24 h following irradiation. The tail moment was quantified (n = 50). c The mRNA expression of DNA damage repair genes were measured by rtPCR 72 h post irradiation. d SIRT1 mRNA expression was measured in a time course 0–72 h following 4 Gy irradiation of 22Rv1. SIRT1 mRNA expression was normalized to GAPDH and to untreated. Data are reported as a mean ± S.D. of three independent experiments (***p < 0.001, ****p < 0.0001, NS not significant, compared to control)