CHEMISTRY OF TUMORS IN GENERAL 413 



stituent of lymph-glands, spleen, and thymus is a compound of 

 nucleic acid and histon (histon nudeinate). If to a watery extract 

 of an organ a few drops of CaCl 2 solution are added, the forma- 

 tion of a precipitate indicates the presence of a lymphatic tissue. 

 If this precipitate is soluble in 1 per cent. NaCl, it is a nuclein- 

 ate corresponding in type to that of the lymph-glands and spleen ; 

 if not soluble, it is of the type of the thymus or leucocytes. 

 Extracts from no other organs give a precipitate with calcium 

 chloride. Spindle-cell sarcomas were found not to give this 

 reaction, but round-cell sarcomas of lymphatic origin do, for 

 they contain the specific nucleinate abundantly. Bang believes 

 that this reaction can be used to distinguish sarcoma arising 

 from lymphoid tissue. This seems to have been confirmed by 

 Beebe, 1 who found nucleo-histon only in lymph-gland tissue, 

 but the distinction between thymus and lymph-gland nucleo- 

 histon is probably not so easily made as Bang intimates. 



Because of their richly cellular structure, cancers may con- 

 tain more nucleoproteid than the tissues from which they arise. 

 Thus Petry 2 found 50 per cent, of nucleoproteid in carcinoma 

 of the mammary gland, as against 30 per cent, in normal 

 tissue. 



Bergell and Dorpinghaus 3 have studied the nature of the 

 proteids 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 proteid of this tumor-mixture was character- 

 ized by the very high proportion of alanin, glutaminic acid, 

 phenylalaniu, and asparaginic acid, there being from 5 to 10 per 

 cent, of each. Leucin was very low, 5-10 per cent, as against 

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

 cocoll and tyrosin were present in small quantities, and serin 

 was probably also present. Neuberg 4 found in cancer proteid 

 1.3 per cent, of tyrosin, 17 per cent, of leucin, scarcely 1 per 

 cent, of glutaminic acid, and 4.92 per cent, of glycocoll. 

 Further investigations along these lines are greatly to be 

 desired. 



On account of the amount of autolysis going on in tumors 

 the products of proteid splitting are usually present. Beebe 5 



1 Amer. Jour. Physiol., 1905 (13), 341. 

 2 Zeit. physiol. Chem., 1899 (27), 398. 

 s Deut. med. Woch., 1905 (31), 1426. 



4 Arb. a. d. Path. Inst. zu Berlin, 1906, p. 593. 



5 Amer. Jour. Physiol., 1904 (11), 139. 



