Tumor accumulation

B12 H11S H2 was the first compound to be used successfully in BNCT. Its synthesis by Soloway [63] was followed by testing in a mouse model, where uptake in a brain tumor model was found. As was discovered much later, the majority of this compound had been oxidized to the disulfide, which in mice has much better tumor accumulation than B,2HnSH2 [58]. Retention in and binding to tumor... 

Noguchi Y, Wu J, Duncan R et al (1998) Early phase tumor accumulation of macromolecules a great difference in clearance rate between tumor and normal tissues. Jpn J Cancer... 

Goto, R., Unno, K., Okada, S., and Tamemasa, O. 1987. Tumor accumulation of D-selenomethionine-75Se in tumor-bearing mice. J. Pharmacobio-Dyn. 10(9), 456-461. 

The anticancer drugs delivered by liposomes include many small molecule drugs such as DOX, daunoru-bicin, platinates, taxanes, camptothecin, etc. The most successful development is DOX-encapsulated pegylated liposomes, with a trade name of Doxil in the U.S. market or Cylax in the European market. Doxil has shown significant clinical advantages over free DOX and conventional DOX liposomes.f Enhanced tumor accumulation of Doxil has been demonstrated in numerous preclinical studies over a variety of tumor models. Similar effects were also observed in clinical uses. 

Seymour, L.W. Miyamoto, Y. Meada, H. Brereton, M. Strohahn, J. Ulbrich, K. Duncan, R. Influence of molecular weight on passive tumor accumulation of a soluble macromolecular drug carrier. European Journal of Cancer... 

An interesting example of a new approach currently in clinical trials is to combine radio-frequency tumor ablation with intravenous liposomal doxorubicin, which resulted in better tumor accumulation of liposomes and increased necrosis in tumors (199, 200). 

To determine the epitope sequences of the peptides, we synthesized various short peptides based on original 15-mer sequence and examined the inhibitory effect of these peptides against tumor accumulation of the corresponding phage clone. Our results indicated that APRPG in original 15 mer sequences was essential for their affinity. 

Ironically, at one time it was thought that Hpd was a purified preparation of its precursor, hematoporphyrin, HP (Figure 1), since the simple chemical steps to make Hpd (acetylation of the secondary hydroxyl groups in acetic acid-sulfuric acid followed by their removal by base) were expected to reform HP and the resulting material appeared to be taken up better by tumors in experimental animal tumors than the HP used without such treatment. However, Schwartz pointed out that it was the impurities in HP preparations that were responsible for tumor accumulation and retention, not HP itself, which, in pure form, in fact, is a very poor tumor localizer [11]. 

The best fluorescence contrast between tumor and normal tissue is obtained if the tumor accumulates porphyrins as much as possible and the normal tissue accumulates very few porphyrins. Fluorescence studies show that superficial lesions of BCC exhibit a maximum porphyrin fluorescence 6 h post ALA application, whereas in nodular lesions the observed intensity is highest after 2-4 h [15]. Detailed biochemical analyses prove that the respective fluorescence intensity correlates well with the extracted quantity of porphyrins [16-19]. In epithelial skin tumors, the porphyrin maxima are achieved 1-4 h after ALA application. In normal skin, porphyrin... 

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