498 THE CHEMISTRY OF TUMORS 



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 an}^ way either 

 for the occurrence of tumors or for the effects that they produce. 



Tumor cells seem to depend upon much the same conditions as nor- 

 mal body cells for their growth, since anything that leads to wasting, 

 malnutrition, or atrophy in the tissues of the host usually tends to 

 impede the rate of growth of the tumor cells, in marked contrast to 

 infectious diseases. Specific attempts to modify tumor growths by 

 diets (_Mendel-Osborne diet) which stunt the animals because lack- 

 ing certain amino-acids necessary for growth, have been successful,^ 

 but it is cUfficult to be sure that this effect depends on the specific ab- 

 sence of a definite substance rather than on general malnutrition.'* 

 Tumor cells made incapable of utilizing carbohydrate through com- 

 plete phlorizin diabetes^ may be unable to grow, and even retro- 

 gress completely. Furthermore, the constituents of the hypophysis 

 that stimulate somatic tissue growth are also said to stimulate growth 

 of tumor tissues.® 



The discovery by B. Fischer^ that fat stained with scarlet-R and 

 injected beneath the skin causes epithelial proliferation resembling 

 but not terminating in cancer, has led to much speculation as to the 

 nature of substances which might cause cells to proliferate lawlessly 

 and malignantly.^ The great frequency of cancer in workers in prod- 

 ucts of destructive distillation of wood (tar, soot, paraffin^) has 

 also indicated the possibility of chemical stimuli causing cancers. A 

 striking instance of chemical stimulation causing cancer formation 

 is furnished by the cases of carcinoma of the urinary bladder, which 

 is a common cause of death in men who work in aniline dyes, both 

 dyers and dye makers being subject to this condition. The dyes that 

 seem to be responsible belong to the group of aromatic amido-hy- 

 droxyls, including safranin, congo-red, benzopurpurin, fuchsin, eosin 

 and others. ^° Nassauer,^°" however, believes that the aniline itself 

 is the active agent. H. C. Ross" has made extensive studies of the 

 relation to cancer of substances which cause leucocytes to multiply, 



= See Sweet, etal, Jour. Biol. Chem., 1915 (21), 309. 



* Rous, Jour. Exp. Med., 1914 (20), 433. 



5 Benedict and Lewis, Proc. Soc. Exp. Biol., 1914 (11), 134. 



« Robertson and Burnett, Jour. Exp. Med., 1916 (23), 631. 



' Verb. Deut. Path. Gcscll., 1906 (10), 20; sec also Haga, Zeit. Krebsforsch., 

 1913 (12), 525; Sachs, Wicn. klin. Woch., 1911 (24), 1551; Stocber, Munch, med. 

 Woch., 1910 (57), 739 and 947. 



* Stoeber has considered substances related to scarlet-R that might have this 

 stimulating effect, and found naphthylaminol most active. In general, fat-soluble 

 organic basic substances only were found to have this propertv, anmng them being 

 indole, skatole and pyridine. (Munch, mod. Woch., 1909 (56), 129; 1910 (57), 

 947). 



'■> See Bayon, Lancet, 1912 (ii), 1579. 

 '» See Leuenberger, Beitr. klin. (^hir., 1912 (SO), 20S. 

 lo^Zeit. angew. Chem., 1919 (32), 333. 

 ^' "Researches into Induced Cell Reproduction and Cniioer," London.] 



