Effects of Low Phenylalanine-Tyrosine Diets on S91 Mouse Melanomas2

Publisher Website
Google Scholar
Abstract
Partially synthetic diets low in phenylalanine and tyrosine selectively inhibited pigmented S91 melanomas carried subcutaneously in DBA/2 mice. S37 sarcomas, carried in the same strain mice, served as nonpigmented controls and were not affected by the various diets fed to the hosts. For the 4-week period studied, the somatic growth of the mice was not obviously impaired by the diets low in phenylalanine and tyrosine. The few tumors that did take and grow were smaller, but were grossly as well pigmented as the control S91 tumors. Manometric and tissue culture studies revealed that the in vivo tyrosine-deficient melanomas could consume as much oxygen and grow as well as control S91 melanomas when incubated in medium containing adequate tyrosine. The in vivo inhibition of S91 growth might have been due to substrate limitation of tyrosinase. However, diminished protein synthesis, due to sequestration of tyrosine into melanin, cannot be definitely excluded as the cause of the poor growth of the tyrosine-deficient melanomas.

This publication has 0 references indexed in Scilit: