Polysaccharides bacterial, antitumor

Several workers have reported that bacterial, antitumor agents cannot have a direct effect on tumor cells, as the bacterial polysaccharide-preparations that produced hemorrhage and necrosis in solid tumors had no effect on tumor cells in vitro208 or in tissue culture.209,210 Seligman and coworkers211 found that only a small propor-... 

Amino sugars are components of antibiotic substances109 and bacterial polysaccharides,1,0 and are therefore of interest. The nucleoside antibiotics amicetin, bamicetin, and plicacetin contain, as the sugar residue, a monoaminopentadeoxy disaccharide that is closely related to maltose. In view of the reported antibiotic and antitumor properties of these pyrimidine nucleosides,111,112 the synthesis of aminodeoxy derivatives of maltose would be of interest. 

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... 

Adams and coworkers21 also examined the chemical composition and antitumor activity of polysaccharide fractions obtained from the Temple University strain of S. marcescens grown in a medium containing sucrose. Some fractions were obtained from bacterial cells by repeated extraction with aqueous phenol, followed by digestion with... 

The nature of the antitumor action of a polysaccharide is not entirely clear, but certain bacterial polysaccharides may directly attack tumors, as evidenced by the resulting intratumoral hemorrhage and necrosis. On the other hand, most of the polysaccharides from other botanical sources cannot be shown to exert any direct action on tumor cells. Their antitumor action must, therefore, be considered to be dependent upon the reaction of the host that is, their effect is host-mediated. It is possible that, in some instances, these two types of action may be interwoven. The discussion in this Section covers only those polysaccharides that effect a host-mediated reaction. 

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