326 On the Origin of Cancer Cells 



are able to do this by a selective process that makes use of the fermentation of the 

 normal body cells. The more weakly fermenting body cells perish, but the more 

 strongly fermenting ones remain alive, and this selective process continues until 

 the respiratory failure is compensated for energetically by the increase in fermen- 

 tation. Only then has a Cancer cell resulted from the normal body cell. 



Now we understand why the increase in fermentation takes such a long time 

 and why it is possible only with the help of many cell divisions. We also under- 

 stand why the latency period is different in rats and in man. Since the average 

 fermentation of normal rat cells is much greater than the average fermentation 

 of normal human cells, the selective process begins at a higher fermentation level 

 in the rat and, hence, is completed more quickly than it is in man. 



It follows from this that there would be no Cancers if there were no fermentation 

 of normal body cells, and hence we should like to know, naturally, from where the 

 fermentation of the normal body cells stems and what its significance is in the 

 body. Since, as Burk has shown, the fermentation remains almost zero in the re- 

 generating liver growth, we must conclude that the fermentation of the body cells 

 has nothing to do with normal growth. On the other hand, we have found that the 

 fermentation of the body cells is greatest in the very earliest stages of embryonal 

 development and that it then decreases gradually in the course of embryonal 

 development. Under these conditions, it is obvious — since ontogeny is the repeti- 

 tion of phylogeny — that the fermentation of body cells is the inheritance of un- 

 differentiated ancestors that have lived in the past at the expense of fermentation 

 energy. 



Structure and Energy 



But why — and this is our last question — are the body cells dedifferentiated when 

 their respiration energy is replaced by fermentation energy? At first, one would 

 think that it is immaterial to the cells whether they obtain their energy from respi- 

 ration or from fermentation, since the energy of both reactions is transformed into 

 the energy of adenosine triphosphate, and yet adenosine triphosphate == adenosine 

 triphosphate. This equation is certainly correct chemically and energetically, but 

 it is incorrect morphologically, because, although respiration takes place for the 

 most part in the structure of the grana, the fermentation enzymes are found for a 

 greater part in the fluid protoplasm. The adenosine triphosphate synthesized by 

 respiration therefore involves more structure than the adenosine triphosphate syn- 

 thesized by fermentation. Thus, it is as if one reduced the same amount of silver 

 on a Photographie plate by the same amount of light, but in one case with dif- 

 fused light and in the other with patterned light. In the first'case, a diffuse 

 blackening appears on the plate, but in the second case, a picture appears ; how- 

 ever, the same thing happens chemically and energetically in both cases. Just as 

 the one type of light energy involves more structure than the other type, the 

 adenosine triphosphate energy involves more structure when it is formed by re- 

 spiration than it does when it is formed by fermentation. 



In any event, it is one of the fundamental facts of present-day biochemistry 



