Fig. 8

γ-H2AX peroxidase staining in paraffin-embedded tissues of canine melanoma xenografts following treatment with SG2000 (single dose of 0.15 mg/Kg or 0.30 mg/Kg). Samples were harvested 2 h and 24 h after administration of the drug. a) Examples of fixed tissue sections with γ-H2AX peroxidase staining from SG2000-treated CMeC-1 tumour compared to sections from untreated control mice (left). All images are x20 magnification, except the bottom left image that is x10 magnification. b) Mean number of γ-H2AX positive cells ± SEM per microscopic field (x 20 magnification) in samples from mice bearing either CMeC-1 (left) or LMeC (right) xenograft (sections from three mice were examined in each case). To calculate the mean γ-H2AX value, at least 150 cells (at least 50 cells per mouse) and 20 fields per sample were counted. Statistical analysis: p ≤ 0.05 = *, ns = not significant