APPENDIX 



ASYMMETRY OF PROTOPLASM AND THE STRUCTURE 



OF THE CANCER CELL 



When, in 11I2:I, ()tto Warburg reijortod thai the oxyda- 

 tive metabolism of cancer cells is somewhat defective 

 and that growth and multiplication in cancerous tissue 

 is provided mainly by fermentative processes accompa- 

 nied by the formation of large quantities of lactic acid, it 

 was thought that the solution of the old mystery about 

 the nature of cancer had been found. Numerous at- 

 tempts of cancer therapy based on this principle, and 

 consisting mostly in inhibiting anaerobic processes in 

 malignant cells, were made. But all these attempts 

 failed. It was then learned that anaerobic metabolism is 

 not a characteristic feature of malignancy, it is observed 

 in many embryonic tissues. 



In view of such failures, James Ewing, director of the 

 Memorial Hospital, New York, remarked before the Na- 

 tional Academy of Science (April, 1938), that the funda- 

 mental nature of malignant growth is probably an in- 

 solvable problem and that investigations on this prob- 

 lem have consumed much time and money without pro- 

 viding knowledge of practical value. There is, accord- 

 ing to him, urgent need for greater support of clinical 

 investigations which yield some practical results. 



In spite of that skeptical attitude toward the pros- 

 pects of fundamental cancer research, the year 1939 

 brought forth an important discovery on the structure of 

 the cancer cell. Two distinguished Dutch chemists, Fritz 

 Kogl and Hanni Erxleben isolated from proteins of ma- 

 lignant cells the unusual optical isomer of glutamic 

 acid (of the right steric series), which never occurs in 

 proteins of healthy cells. This important finding was 

 rapidly followed by significant practical applications. 

 Waldschmidt-Leitz (1939) discovered in the serum of 

 cancer patients proteolytic enzymes with unusual stereo- 



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