Fig. 4

Histological appearance of the H8N8 breast tumors after conventional RT. Representative images of an untreated tumor (CN), a tumor that received RT (RS225) and a tumor that received RT and BaNPs (RS225-NP) are shown. H&E staining demonstrates large necrotic regions (asterisks) in tumor tissue of CN, while the tumor mass seems compact (§). RS225 and RS225-NP treated tumors appear more fractured and display small but distributed necrotic tumor regions. MTS staining confirms the absence of fibrosis in all specimens. CD68 staining shows a large mass of CD68 positive cells (predominantly macrophages) in the necrotic area in CN (#), while absent in the rest of the tumor. In RS225 and RS225-NP treated tumors, CD68 positive regions can be found distributed within the entire tumor. Note that the tumors were divided before paraffin embedding and might therefore appear incomplete.