ADVANCES I N CANCER RESEARCH VOLUME V This Page Intentionally Left Blank ADVANCES IN CANCER RESEARCH Edited by JESSE P. GREENSTEIN National Cancer Institute, National Institutes of Health, U. S. Public Health Service, Bethesda, Maryland ALEXANDER HADDOW Chester Beatty Research Institute, Institute of Cancer Research, Royal Cancer Hospital, London, England Volume V @ 1958 ACADEMIC PRESS INC., PUBLISHERS, NEW YORK, N. Y. COPYRIGHT 0 1958 BY ACADEMICPRESSINC. 111 FIFTHAVENUE NEWYORK3, N. Y. All Rights Reserved N o part of this book may be reproduced in any form by photostat, microfilm, or any other means without written permission from the pztblishers. Library of Congress Catalog Card Number 52-13360 PRINTED IN THE UNITED STATES OF AMERICA CONTRIBUTORS TO VOLUME V I .c 20 0 .- 0 0 a 0 5 10 0 30 40 50 Time of incubation (min.) FIG.8a and b. Intracellular distribution of radioactivity in Krebs I1 ascites tumor cells after incubation in vitro with glycine-C14. The washed cells were incubated in a bicarbonate medium under aerobic conditions a t 37°C. After incubation, the cells were disrupted by ultrasonic disintegration and the components fractionated in a sucrose medium (from Campbell el al., 1957). 138 P. N. CAMPBELL Littlefield and Keller (1957) have followed the incorporation of L-Valine-C14 into Ehrlich ascites cells incubated in fortified ascitic fluid. After lysis of the cells, the microsome fraction was treated either with deoxycholate or sodium chloride. The results obtained are shown in Fig. 9. As with liver, this shows that the ribonucleoprotein particles are the initial site of incorporation. When reticulocytes are incubated with ~-leucine-C’~, the initial incorporation of radioactivity is into the microsomal protein (Rabinovitz and Olson, 1956). The microsomes had a content of 20% ribonucleic acid. After treatment with deoxycholate, the residue had a content of 30% ribonucleic acid and the protein contained more radioactivity than that of the untreated microsomes. r Deoxycholate- sol. 6 50E 0 5 10 15 20 25 30 Time of incubation (min.1 FIQ.9. Time curve of incorporationof ~-valine-Cl~ into proteins of ascites tumor cells incubated in aacitic fluid fortified with glucose. The curve for the “pH5 enzyme” fraction was almost. identical with that of the whole cell. The per cent RNA of the deoxycholate-insoluble particles is indicated on the chart for each sample. The per cent RNA averaged 8 for the whole cells, 4 for the “pH5 enzyme,” and 11 for the deoxycholatesoluble fraction of the microsomes (from Littlefield and Keller, 1957). B. Slices and Brei. When rat liver slices are incubated in a bicarbonate medium under aerobic conditions in the presence of glycine-C14,the most active cell fraction is associated with the microsomes, as under in vivo conditions (Campbell et al., 1957). Typical results are shown in Fig. 10. If regenerating liver taken 40 hours after partial hepatectomy, when the rate of protein synthesis is maximal, is used, the incorporation into all the fractions is greatly enchanced compared with the normal liver as shown in Fig. 10. If, however, slices of liver tumor are incubated under the same conditions, the incorporation into the microsomes, supernatant fraction, and mitochondria is similar to normal liver; but the incorporat.ioninto the nuclear fractions of the tumor greatly exceeds that into the same fraction PROTEIN SYNTHESIS WITH REFERENCE TO GROWTH PROCESSES 139 of normal liver. Therefore as with ascites, the nuclear fraction appear