CHROMOSOMES AND ECTOPLASM 



The striking similarity between these figures of abnormal 

 mitoses and those found in cells of human cancer deserves 

 some comment. 



Almost fifty years ago Galeotti described and figured 

 abnormal mitoses in human cancerous cells. Later he 

 showed that poisons, acting on skin cells of the salamander, 

 induce pathological mitoses closely resembling those found 

 in cancer. Subsequently various investigators have con- 

 firmed Galeotti's findings. Cancer cells of man and of 

 other mammals in tissue culture likewise show abnormal 

 mitoses. If one compares under the microscope my prepa- 

 rations of these abnormal mitoses in eggs of Nereis with 

 those of human cancer cells, one notes at once that, except 

 for their greater clearness and sharpness due to more excel- 

 lent technique, the mitotic figures in the eggs bear the 

 closest resemblance to those in the cancer cell. How far 

 this resemblance has common cause, it is hazardous to 

 assert. And this for the following reasons. 



In the first place, eggs of a worm, freshly discharged 

 into the sea, are far removed from the cells of warm blooded 

 animals, which in the intact organism stand in a quite 

 different relation to their environment, conditioned by 

 nervous and humoral integrations. Conclusions for human 

 cells derived from studies on cells of other mammals even 

 are not always safe. Hence we are wary in making final 

 statements on the basis of animal experimentation concern- 

 ing human disorders, the more so since man varies so much 

 one with the other, and since in one individual the har- 

 monious adjustment of cells, their capacity for self-regula- 

 tion, so greatly depends upon that so little understood 

 principle of individuality, which in the final analysis goes 

 back to the chemical make-up of the ground-substance of 

 every single cell;^ from it emanate what we designate indi- 

 vidual resistance and susceptibility. 



1 Just, 1936b. 



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