500 THE CHEMISTRY OF TUMORS 



in tumors by determining the proportion of the various amino-acids 

 that compose them. Because of the amount of material necessary 

 for the ester method, they were obhged to use a mixture of various 

 primary and secondary cancers and one sarcoma. The protein of 

 this tumor-mixture was characterized by the very high proportion of 

 alanine, glutaminic acid, phenylalanine and aspartic acid, there being 

 from 5 to 10 per cent, of each. Leucine was very low, 5-10 per cent., 

 as against 20 per cent., or higher, found in most normal tissues. Gly- 

 cine and tyrosine were present in small quantities, and serine was prob- 

 ably also present. Neuberg^^ found in cancer protein 1.3 per cent, 

 of tyrosine, 17 per cent, of leucine, scarcely 1 per cent, of glutaminic 

 acid, and 4.92 per cent, of glja^inc. In five human tumors of different 

 sorts, Kocher-- found high figures for diamino-nitrogen; his averages 

 were: arginine, 12.42; histidine, 4,86; lysine, 11.23; total, 28.47 

 per cent, of the protein nitrogen. Drummond's'^ careful studies in 

 this field have shown that the diamino-acid content of tumors is 

 generally slightly higher than in corresponding normal tissues, prob- 

 ably varying directly with the amount of nuclear material, there being 

 nothing found to indicate that the hexone bases are in any way respon- 

 sible for increased growth. Strange, and as yet unexplained, varia- 

 tions in tryptophane content in various tumors were found by Fasal,-"* 

 some having a very high try{)tophane figure, while in others none could 

 be found. Centanni" found that trjqitophanc and tyrosine inhibit, 

 while skatolo and indole stimulate carcinoma growth. 



Certain authors have believed that the cancer cell has a specific 

 chemistry,-*^ but most of these analyses, including that of Abderhalden 

 and Mcdigreceanu,-^ seem to indicate that cancer proteins have much 

 the same composition as normal proteins. Cramer and Pringle-^ 

 find that there is less nitrogen in mouse cancers than in equal amounts of 

 other mouse tissue, the decrease being in the coagulable nitrogen, 

 incoagulable nitrogen being relatively increased; a given amount of 

 nitrogen produces more cancerous than normal tissue. The water 

 content of rapidly growing tissues, whether normal or cancerous, was 

 found to be high. This corresponds with the analysis of Robin,-' 

 who found the water content high and nitrogen low in carcinomas of 

 the liver, suli)hur being especially low, and C^hisholnr*" has found the 

 proportion of nitrogen in several human tumors lower than in the soma- 



"^^ .\rb. a. d. Path. Inst, zu Berlin, 1906, p. 593. 

 " Jour. Biol. Cheni., 1915 (22). 295. 

 "Biochem. Jour., 1910 (10), 473. 

 ^^ Biocheni, Zeit., 1913 (55), 88. 

 " Tumori, 1913 (2), 406. 



-» Blumenthal, Zeit. Krebsforsch., 1907 (5), 183. 

 -' Zeit. phvsiol. Cliem., 1910 (09), 00. 



=« I'roc. Koval Soc, B., 1910 (S2), 315; Jour. Phvsiol., 1910 (50), 322. 

 ■'"Cent. Phvs. Path. StotYwechs., 1911 (0). 577. Bull. .Vcad. M6J., 1919 (81), 

 799; Coinpt. Rend. Acad. Sci., 1919 (108), 1071. 

 "« Jour. Pathol, and Bact., 1913 (17), 000. 



