CHE Ml ST in or TUMONS J\ (IKSEK.XL 495 



lated to Bergell's iiiuliii<i- of a liiyh diunujio-acid coiitont in mouse 

 cancer.^^ However, AVells and Long '- found the proportion of purine 

 nitrogen in tumors of several classes to be much lower tlian might 

 be expected from the nuclear content as shown by the microscope; 

 also Satta/^ found unexpectedly low phosphorus figures and Yosh- 

 imoto/* found no parallelism between the number of nuclei and the 

 nuclein content. The purines present in tumor tissues are quite the 

 same in nature and proi^ortion as in normal tissues (Wells and Long), 

 as also are the nucleoproteins. 



Bergell and Dorpinghaus ^■' have studied the nature of the proteins 

 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 obliged 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 asparaginic 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. 

 Glycocoll and tyrosine were present in small quantities, and serine 

 was probably 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 glycocoll. In five human tu- 

 mors of different sorts, Kocher ^^^ found very high figures for dia- 

 mino-nitrogen, which he correlates with the growth function of lysine ; 

 his averages were : arginine, 12.42 ; histidine. 4.86 ; lysine, 11.23 ; 

 total, 28.47 per cent, of the protein nitrogen. Strange, and as yet un- 

 explained, variations in tryptophane content in various tumors were 

 found by Fasal,^*"' some having a very high tryptophane figure, while 

 in others none could be found. Centanni ^'"' found that tiyptophane 

 and tyrosine inhibit, while skatole and indole stinuilate carcinoma 

 growth. 



Certain authors have believed that the cancer cell has a specific 

 chemistry,^" but most of these analyses, including that of Abderhalden 

 and ^Fedigreceanu,^* 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, 



11 Zeit. f. Krebsforsch., 1907 (5), 204. 



12 ZbifZ., 1913 (12), .598. 



13 Arch. Ital. Biol., 1908 (49), .380. 

 i-t Biochem. Zeit., 1909 (22), 299. 

 i-'Deut. mod. Woch., 190.5 (31), 1420. 



i« Arl). a. d. Path. Inst, zii Berlin, 190G, p. .593. 



i«a,Tour. Biol. Chem., 1915 (22), 295. 



i''b Biochem. Zeit., 1913 (55), 88. 



I'"- Tumori, 1913 (2). 



1- Blunienthal, Zeit. Krehsforseh.. 1907 (5), 183. 



IS Zeit. phvsiol. Chem., 1910 (09), 60. 



laProc. Royal Soc., B., 1910 (82), 315; Jour. Phvsiol., 1910 (50), 322. 



