I 



ENZYMES OF TUMORS 505 



(Cramer).*" A greater proportion of potassium was found in primary 

 than in secondary growths by Mottram;''' sodium was the same in 

 each; there is more potassium in squamous cell carcinoma than in 

 round cell sarcoma. Robin*^'- states that in cancerous livers the cancer 

 tissues contains more inorganic matter than the normal liver tissue 

 about it. Cattley*' found the microchemic distribution of potassium 

 the same in cancer as in normal cells, and the same seems to be true of 

 manganese.*^ 



Schwalbe''^ found that cancer-cells contain iron in a condition de- 

 monstrable by the Berlin-blue reaction, and occurring independent 

 of hemorrhages. Tracy^® found that tumors reacted microscopically 

 for iron, either free or in the form of an albimiinate, only in areas where 

 hemorrhages had occurred. Nuclear or organic iron could be detected 

 in the nuclei, occurring in a network arrangement. In other words, 

 iron occurs in tumors, both quantitatively and qualitatively, exactly 

 as in normal cells of the same type. The same writer" found in tumors 

 by microchemical reactions, that phosphorus in the form of nucleo- 

 proteins likewise shows no essential differences from its distribution 

 in normal tissues. 



In this connection may be mentioned the observations of Hem- 

 meter,*** who found that the cells of carcinoma of the mammary gland 

 will shrink when placed in physiological salt solution or in the serum 

 of the patient, whereas normal cells swell when placed in cancer-juice. 

 This suggests that the osmotic pressure, and, by inference, the amount 

 of inorganic constituents, is lower than in normal tissues. Crystal- 

 loids, such as KI, diffuse readily into cancer tissue.*^ 



(4) Enzymes. — The rapid and extensive autolysis that occurs in 

 tumors, as shown both morphologically and by the presence of the 

 products of protein cleavage in them, indicates that tumor cells 

 resemble all other cells in possessing intracellular proteolytic enzj^mes. 

 Because of autolysis, puncture fluids in cancer of serous surfaces show 

 an increased amount of incoagulable nitrogen (J\Iorris),^° and they 

 may show free amino-acids ( Wiener), ^^ while there is a slight increase 

 in the incoagulable nitrogen of the blood (Takemura).^- 



There is considerable but not undisputed evidence that cancer tis- 



s" Biochem. Jour. 1918 (12). 210. 



" Arch. Middlesex Hospital, 1910 (19), 40. 



«2 Compt. Rend. Acad. Sci., 1913 (156), 334. 



^^ Lancet 1907 (172) 13. 



«^ Medigreceanu, Pro'c. Royal Soc, B, 1912 (86), 174. 



" Cent. f. Path., 1901 (12), 874. 



66 Jour. Med. Research, 1905 (14), 1. 



" Martha Tracy, Jour. Med. Research, 1906 (14), 447. 



68 Amer. Jour. Med. Sci., 1903 (125), 680. 



69 Van den Velden, Biochem. Zeit., 1908 (9), 54; see also Wells and Heden- 

 burg. Jour. Infect. Dis., 1912 (11), 349. 



'"Arch. Int. Med., 1911 (8), 457. 

 '1 Biochem. Zeit., 1912 (41), 149. 

 " Ibid., 1910 (25), 505. 



