342 



M. WOODS, K. WIGHT, J. HUNTER, D. BURK 



VOL. 12 (1953) 



TABLE V 



RESPONSE OF S-QI MELANOMA SLICES TO CRYSTALLINE ZINC-INSULIN (4 UNITS PER ML) IN 3 DIFFERENT 

 EXPERIMENTS. EXPERIMENT I IN HANK-SIMMS WITH POOLED SLICES FROM TWO TUMORS OF THE SAME 

 TRANSPLANT SERIES (38 DAYS OLD), EXPERIMENT II IN HANK-SIMMS WITH POOLED SLICES FROM THREE 

 TUMORS OF THE SAME TRANSPLANT SERIES (45 DAYS OLD), AND EXPERIMENT III IN WARBURG-OKAMOTO 

 WITH POOLED SLICES FROM TWO TUMORS 27 AND 45 DAYS OLD RESPECTIVELY. 0.625% DEXTROSE, 



0.03 M KHCO3, 95% Ng, 5% COg IN ALL CASES. 



TABLE VI 



METABOLIC PATTERN OBSERVED IN S-9I MELANOMA WHICH SHOWS THAT ELEVATION OF THE R.Q. CAN 

 OCCUR WITHOUT CONCOMITANT INCREASE IN MANOMETRICALLY MEASURABLE ACID FORMATION. HANK- 

 SIMMS MEDIUM WITH POOLED SLICES FROM THREE TUMORS OF THE SAME TRANSPLANT SERIES (44 DAYS 

 OLD). DEXTROSE 0.625%, 0-03 M KHCO3 AND GAS PHASE EITHER 95% Oj, 5% COg OR 95% No, 5% COo. 



Metabolic factor 



Control 



1.12 Zincjml 



Plus 4 units 



crystalline 



Zn-insulinjml 



DISCUSSION 



Recent work^^'^'^'^^'^^ j^^s shown that tissue sHces and homogenates of various 

 normal adult tissues can be made to show a vigorous glycolysis if hexose diphosphate 

 and co-factors (ATP, DPN, niacinamide, magnesium, phosphate) are supplied in sufficient 

 amount. However, one marked difference (aside from a higher Qq^ between these tissues 

 and malignant tissues is the greater capacity of the latter to utilize glucose as the 

 substrate for anaerobic glycolysis. Adult brain is often cited as a non-malignant tissue 

 possessing a considerable capacity to glycolyse glucose in vitro. However, we have found 

 that under certain in vitro conditions, where the anaerobic glycolysis of tumors remains 

 at a high level, that of brain decays rapidly to a low level, although aerobically a liigh 

 glycolysis is maintained. Thus, part of the difference between the metabolism of adult 

 brain and certain tumors, e.g. melanoma, lies not so much in the absence of potential 

 glycolytic capacity in the brain as in the relative instability of the glycolytic metabolism 

 of this tissue under certain anaerobic conditions. It is probable that this reflects the 



References p. 346. 



