67Ga uptake and heparan sulfate content of Ehrlich solid tumor in mice

The relationship between 67Ga uptake and heparan sulfate (HS) content in Ehrlich solid tumor (EST) of mice was investigated, and the effect of cyanomethylamine, papain, streptozotocin, or bleomycin pretreatment on 67Ga uptake in EST was studied. 67Ga uptakes in EST and kidney were much higher than other tissues, and these tissues also contained large amounts of HS. 67Ga uptakes and HS synthesis in the EST were inhibited by pretreatment with cyanomethylamine or papain (inhibitors of fibrosis). Parallel reductions of 67Ga uptake and HS synthesis in EST were observed in EST transplanted into streptozotocin-induced diabetic mice. The weight of EST in the bleomycin-injected group was decreased to less than half of the control, but no effect was observed on 67Ga uptake per gram of EST. These results suggest that 67Ga uptake in the tumor and inflammatory lesions are related to the quantity of HS in these tissues, and the correlation between the uptake of 67Ga and the rate of cellular proliferation is secondary.