FREE AMINO ACIDS IN ANIMAL TISSUE 285 
from the animal showed that the free amino acid pattern of the transplantable 
squamous cell carcinoma was completely different from that found in epidermis of 
normal adult and newborn mice, in epidermis made hyperplastic by application of 
carcinogen, or in non-malignant papillomata’. The extension of these observations 
to other tissues and types of tumors showed that each tissue of the healthy adult mouse of 
a particular strain has a characteristic distribution of free amino acids, while quite 
similar patterns of free amino acids are found in many different types of transplanted 
and spontaneous tumors’. The latter results indicate (see ref. g for similar data on 
1 ’ 2 
_ 
Dex, 
HEPATOMA 
ca 

19 
SQUAMOUS CELL 
CARCINOMA 
Figs. 1-4. Comparison of free amino acid patterns of mouse liver (Fig. 1) with those found in a 
transplantable hepatoma (Fig. 2) and epidermis (Fig. 3) and squamous cell carcinoma (Fig. 4). 
Extracts obtained from 75 mg of fresh weight of tissue were employed for descending two- 
dimensional chromatography (phenol, right to left; lutidine, bottom to top). Constituents on 
chromatograms: tyrosine, 1; phenylalanine, 2; leucine and isoleucine, 3; valine, 4; taurine, 5; 
proline, 6; hydroxyproline, 7; alanine, 8; threonine, 9; serine, 10; histidine, 11; glycerylphos- 
phorylethanolamine and/or f-alanine, 12; glutamine, 13; glycine, 14; arginine, 15; lysine, 16; 
glutamic acid, 17; aspartic acid, 18; ethanolamine phosphate, 19; cystine (cysteic acid), 20; 
glutathione, 21r. 
EPIDERMIS. 

References p. 348/349 
