412 THE CHEMISTRY OF TUMORS 



that are hemolytic and toxic. 1 Whether these are the cause of 

 cancer cachexia, however, may be questioned; but they are 

 sufficient to account for most of the experimental results as 

 yet obtained. No substance has yet been isolated from or 

 detected in malignant growths that is peculiar to them and not 

 found in normal cells, and still less has any substance been 

 detected that accounts in any way either for the occurrence of 

 tumors or for the effects that they produce. 



Nevertheless, numerous observations have been made con- 

 cerning the chemistry of tumors, which, although they do not 

 as yet throw any important light on the fundamental problems 

 of tumor pathology, are of much interest. These may be briefly 

 summarized as follows : 



A. CHEMISTRY OF TUMORS IN GENERAL 



(1) Proteids. Earlier studies showed that tumor growths 

 contain the same sorts of proteids as do normal tissues, and 

 apparently in about the same proportions. Recently investiga- 

 tions have been made concerning the more minute chemical 

 features. Wolff 2 has studied the proteids obtained in the juice 

 expressed from cancer-cells by the Buchner press. In normal 

 tissues such cell-juice contains, almost constantly, nearly equal 

 proportions of albumin and globulin. In carcinoma, how- 

 ever, the albumin is usually three or more times as abundant 

 as is the globulin. Of the globulins, it is particularly the 

 euglobulin that is reduced, in some instances being nearly 

 absent. In tumor-free liver tissue between carcinomatous 

 growths the proportion of albumin was found increased above 

 that normal for liver tissue. Wolff found no qualitative dif- 

 ferences between cancer proteids and normal cell proteids. 

 Joachim has found, similarly, that in cancerous ascites the pro- 

 portion of albumin is much higher than in ascites from other 

 causes. This is rather remarkable, in view of the fact that in 

 cachexia the proportion of albumin in the blood and in exudates 

 sinks much more rapidly than does the proportion of globulin. 3 



In all probability the nucleoproteids of tumors share the spe- 

 cific characteristics of the nucleoproteids of the tissues from 

 which they arise at least this is the case with the nucleoproteids 

 of lymphosarcoma, according to Bang. 4 The characteristic con- 



1 Kiilf (Zeit. f. Krebsforschung, 1906 (4), 417) considers the proteolytic 

 enzymes of much importance in the causation of cancer cachexia. 



2 Zeitschrift f. Krebsforschung. 1905 (3), 95 : Medizinische Klinik, 1905 (1), 

 13. 



3 Umber, Zeit. klin. Med., 1903 (48), 364. 

 * Hofmeister's Beitr., 1903 (4), 368. 



