The combined use of 188Re-IDA-D-[c(RGDfK)]2 and TMZ (2 mgkg−1) resulted in the best anti-tumor results as confirmed by histological examination that demonstrated a significant reduction in microvessel density (97.9% reduction of positive % area for CD31 expression) and integrin receptors (98.5% reduction of positive % area for integrin αvβ3 expression) (Figure 5C). The gene discussed is PECAM1; the disease is neoplasm.