Antitumoral polysaccharide

MORiNAGA T (1985) Studies on an antitumor polysaccharide RBS derived fi om rice bran. 1. Preparation, physico-chemical properties, and biological activities of RBS. Yakugaku Zasshi, 105(2) 188-93. 

Mizuno TA, Development of antitumor polysaccharides from mushroom fungi, Food dr Food Ingred J 67- 3- 5, 1996. 

The earliest antitumor-polysaccharide known was isolated in 194 from Serratia marcescens and became known as Shear s polysaccharide (Shear et al. 26)). Later on, a whole steries of polysaccharides of bacterial origin was tested and it became... 

In recent years, many fungi were examined for potent antitumor polysaccharides and a great number of different carbohydrate polymers could be isolated and shown to have a quite distinct antitumor activity. The most active ones have p-1,3- and 1,6-linkages and glucose as the main structural monomer. 

However, as it has been concluded by Whistler et al.32), all the polysaccharides so far examinated are active in transplanted tumors but do not seem to be useful yet for clinical trials in human cancer therapy. The search for new polysaccharides which are more strongly active antitumor agents than those so far discovered stands at a challenge for further studies on antitumor polysaccharides. 

Whistler, Roy L., Bushway, Alfred A., Singh, Prem P., Nakahara, Waro, and Tokuzen, Reiko, Non-cytotoxic, Antitumor Polysaccharides, 32, 235-275... 

The mannans, by i.p. injection, were well tolerated in mice, but showed high toxicity by i.v. administration.150 The O-(carboxymethyl) derivative was not toxic by i.v. administration, and still showed high activity.150,152 Antitumor polysaccharides have also been obtained from Trametes.153... 

Similarly, Tanaka227 found that formation of serum antibody for sheep erythrocytes was unaffected by bagasse polysaccharide, another antitumor polysaccharide. Bagasse polysaccharide did not elicit hyperplasia of the reticuloendothelial system in mice, and thus there seemed to be no apparent correlation between carbon clearance and administration of bagasse polysaccharide. Considering that the... 

All of the host-mediated, antitumor polysaccharides so far noted have been isolated and identified, based on a bio-assay system normally using Sarcoma 180 in mice. The allogeneic, tumor-graft rejection-mechanism is the basis of this system. 

Despite the fact that all of the so-called antitumor polysaccharides hitherto discovered proved totally without effect on autochthonous, animal tumors, some relationships may exist between the mechanism of allogeneic, transplanted-tumor rejection and the suppression of autochthonous tumors, as indicated by experiments of Tokuzen and Nakahara.253,254... 

The polysaccharides so far examined, although strongly active in suppressing transplanted tumors, do not seem eligible for clinical trial in human cancer therapy. Therefore, to search for new polysaccharides more strongly antitumor-active than those thus far discovered, and, especially, ones that may have an inhibiting action on autochthonous tumors, stands as a challenge for further studies on antitumor polysaccharides. 

Sasaki, T. Takasuka, N. Further study of the structure of lentinan, an antitumor polysaccharide from Lentinus edodes. Carbohydr. Res. 1976, 47, 99-104. 

Ohno, N., lino, K., Suzuki, L, Oikawa, S., and Yadomae, T., Neutral and acidic antitumor polysaccharides extracted from cultured fruit bodies of Grifola frondosa, Chem. Pharm. Bull. (Tokyo), 33,1181-1186,1985. 

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