1910.] Contributions to the Biochemistry of Growth. 319 



Table III. — Giving the Absolute Amounts of Total Nitrogen, Coagulable Nitrogen, and 

 Incoagulable Nitrogen, expressed in Percentage of the Weight of Tissue, in the Various 

 Tissues. 





Tumour. 



Liver. 



Muscle. 



Aiiiiuiil. 



Total 

 N. 



Coag. 

 N. 



Incoag. 

 N. 



Total 

 N. 



Coag. 

 N. 



Incoag. 

 N. 



Total 

 N. 



Coag. 

 N. 



Incoag. 

 N. 



Rat I 



Rat II 



Eat III 



2 -39 

 2-80 



No 



1 -92 

 2-22 

 tumour 



0-47 

 0-58 



3 -04 

 3 -26 

 3 -08 



2-74 

 2 -94 

 2-76 



0-30 

 0-32 

 0-32 









Mouse I ... 

 Mouse II ... 

 Mouse III ... 



2-251 



2 -29 ^ 2 -28 



2 -29 J 



1 -76 



0-52 



3-121 



2 -77 U -03 



3 -19 J 



2 -50 



0-53 



2-771 

 — 1-2 -83 

 2 -88 J 



2 -38 



0-45 



evidence of the reliability of the methods. The table shows tliat both, for 

 mice and rats, and for earcinomata and sarcomata, the tissues of rapidly pro- 

 liferating malignant new growths show a marked diminution, amounting to 

 about one-quarter, of the substances which can be coagulated by alcohol. The 

 substances which are nob coagulated by alcohol show a slight but distinct 

 increase as compared with somatic tissue. 



Summary. 



The rapidly growing cells of a malignant new growth, and the cells of the 

 animal bearing it, show a marked quantitative difference in their chemical 

 composition. Weight for weight, the cancer cells contain only about three- 

 fourths of the protein substances present in the tissues of the host. In other 

 words, with the same amount of protein a bigger mass of tumour tissue tlian 

 of host tissue can be built up. The simpler (abiuret) nitrogenous products of 

 cell metabolism, however, are present in slightly greater amount in the 

 cancerous tissue. 



These results are important in themselves, for the light they throw upon 

 the chemistry and the metabolism of the cancer cell. The interpretation of 

 their bearing on the growth of cancerous tissue may only be attenqjted with 

 caution. As regards the rapidity of growth, it is possible to formulate con- 

 clusions ; since the tissue of a neoplasm can be built up witli less protein 

 than the same weight of host tissue, the former must grow more rapidly than 

 the latter under circumstances where both are using up nitrogen for mere 

 growth at the same rate. In order to explain the rapidity of giowth, it is not 

 necessary to assume that the cancer cells build up protein more rapidly in a 

 given time than the cells of the host, since we have shown that the former 



