Searches for exploitable biochemical differences between normal and cancer cells. V. Cellular conservation of purines.

Searches for exploitable biochemical differences between normal and cancer cells. II. Nucleic acid purine metabolism in human tumors.

Searches for exploitable biochemical differences between normal and cancer cells. VII. Anabolism and catabolism of purines by minced tissues.

Minced neoplasms and minced tissues of the host animals were incubated with xanthine-8-C 14, hypoxanthine-8-C 14, adenine-8-C 14, or guanine-8-C~4; and aqueous alcoholic extracts of these mixtures were examined by means of the chromatographicradioautographic technic. I t was found that relatively less catabolism and more anabolism occurred in the neoplastic tissues than in most of the host tiss...

Searches for exploitable biochemical differences between normal and cancer cells. X. Catabolism of purines by regressing tumors.

The in vitro anabolism and catabolism of radioactive purities by minces and of radio active purines and purine ribonucleotides by sonicates of growing and regressing tu mors were investigated with the aid of paper chromatography, radioautography, and radioassay. Two systems of growing and regressing tumors were used: (a) cyclophosphamide-sensitive and cyclophosphamide-resistant plasmacytomas gr...

Searches for exploitable biochemical differences between normal and cancer cells. IX. Anabolism and catabolism of purines by hepatomas 5123 and H-35.

The extents of anabolism and catabolism in vitro of purines and purine ribonucleotides by rat tissues, Morris Hepatoma 5123, and Reuber H-35 hepatoma were deter mined. The results are compared with those obtained previously for Novikoff hepato ma. Hepatoma 5123 was more active catabolically than any of the host tissues exam ined, including liver; H-35 tumor was about one-half as active cataboli...

Searches for exploitable biochemical differences between normal and cancer cells. III. Effects of aminoimidazolecarboxamide on purine metabolism.

nucleic acid guanine (1, 4, 5). One possible ex planation of this observed difference between tu mors and normal tissues might be the existence in tumors of high levels of guanase which, by degra dation of guanine, would prevent its incorporation into nucleic acids. Although the available litera ture (8, 11) indicates no significant differences be tween tumors and normal tissues in levels of en...