azaguanine and Liver-Neoplasms

The effect of 3' methyl-4-dimethylaminoazobenzene (3'-Me-DAB) in the induction of malignant transformation and of 8-azaguanine-resistant mutations and chromosomal aberrations was studied in a diploid strain derived from normal rat liver cells. The cells were malignantly transformed by treatment with 3'-Me-DAB 1.7 micrograms/ml for 130 to 221 d or 1.7 micrograms/ml for 53 d followed by 24.9 micrograms/ml for 27 to 77 d. The untreated control cells did not transform spontaneously until the 232nd d in culture. Some properties of the 3'-Me-DAB-treated cells were compared to those of untreated control cells but no reliable marker for predicting the tumorigenic potential of the cells was found. The single addition of 3'-Me-DAB caused little induction of 8-azaguanine-resistant mutations and chromosomal aberrations to the cells. However, mutations and chromosomal aberrations were significantly induced by N-acetoxy-4-methylaminoazobenzene, an active metabolite of 4-dimethylaminoazobenzene or 3'-Me-DAB in the presence of liver microsomes.

Topics: Animals; Azaguanine; Cell Transformation, Neoplastic; Chromosome Aberrations; Clone Cells; Drug Resistance; Liver; Liver Neoplasms; Methyldimethylaminoazobenzene; Neoplasms, Experimental; p-Dimethylaminoazobenzene; Rats

Topics: Animals; Azacitidine; Azaguanine; Carcinoma, Hepatocellular; Cells, Cultured; Cytidine; Dactinomycin; Electrophoresis, Polyacrylamide Gel; Fluorouracil; Guanosine; Isotope Labeling; Liver; Liver Neoplasms; Neoplasms, Experimental; Rats; RNA, Neoplasm; RNA, Ribosomal; Spectrophotometry, Ultraviolet; Time Factors; Tritium; Uridine

Topics: Animals; Azacitidine; Azaguanine; Carbon Radioisotopes; Carcinoma, Hepatocellular; Electrophoresis, Polyacrylamide Gel; Guanosine; Liver Neoplasms; Methionine; Neoplasms, Experimental; Rats; RNA, Neoplasm; RNA, Ribosomal; Transcription, Genetic; Tritium; Uridine

Topics: Aminopterin; Animals; Azaguanine; Carcinoma, Hepatocellular; Cell Fusion; Cell Line; Chromosomes; Clone Cells; Culture Media; Drug Resistance; Humans; Hybrid Cells; Hypoxanthines; Karyotyping; Liver Neoplasms; Lung; Parainfluenza Virus 1, Human; Pentosyltransferases; Rats; Thymidine

Topics: Adrenal Glands; Adrenalectomy; Age Factors; Animals; Azacitidine; Azaguanine; Carbon Isotopes; Carboxy-Lyases; Carcinoma, Hepatocellular; Cycloheximide; Dactinomycin; DNA; Enzyme Induction; Hepatectomy; Hydrocortisone; Liver; Liver Neoplasms; Liver Regeneration; Male; Ornithine; Rats; Solubility

Topics: Animals; Anti-Bacterial Agents; Antimetabolites; Azaguanine; Carbon Isotopes; Carcinoma, Hepatocellular; Cell Nucleus; Centrifugation, Density Gradient; Cycloheximide; Cytoplasm; Depression, Chemical; Feedback; Leucine; Liver; Liver Neoplasms; Male; Metabolism; Neoplasms, Experimental; Orotic Acid; Puromycin; Pyrrolidines; Rats; Ribosomes; RNA; Stimulation, Chemical; Time Factors; Tryptophan

1. The ribosomal components in the postmitochondrial supernatant of a rat hepatoma (hepatoma 7800) and the corresponding host liver were examined for diversity and functional competence. 2. The ;free' and ;membrane-bound' polyribosomes of both tissues were equally active in vivo and had equilibrated with newly synthesized ribosomes 4hr. after administration of [6-(14)C]orotic acid. 3. The inactive monomer-dimer pool in hepatoma 7800 was unattached to membranes and a larger fraction of the polyribosomes was free in hepatoma than in liver. 4. By using sensitivity to puromycin as a criterion, evidence was obtained that most of the polyribosomes in hepatoma 7800 were active in vivo. 5. Actinomycin, azaguanine and carbon tetrachloride caused marked conversion of polyribosomes into inactive monomers and dimers in the host liver and moderate conversion in the hepatoma. 6. Significant accumulation of ferritin and shifts in the mean polyribosome size to the lighter species occurred in the host liver of rats bearing large hepatomas.

Topics: Animals; Azaguanine; Carbon Isotopes; Carbon Tetrachloride; Carcinoma, Hepatocellular; Dactinomycin; Ferritins; Liver; Liver Neoplasms; Neoplasms, Experimental; Orotic Acid; Puromycin; Rats; Ribosomes

Topics: Animals; Azaguanine; Carbon Isotopes; Carcinoma, Hepatocellular; Dactinomycin; Liver; Liver Neoplasms; Male; Neoplasms, Experimental; Orotic Acid; Rats; Ribosomes; RNA, Messenger

Topics: Alkylating Agents; Animals; Antineoplastic Agents; Azaguanine; Azaserine; Carcinoma, Ehrlich Tumor; Carcinoma, Hepatocellular; DNA; DNA, Neoplasm; Fluorouracil; Idoxuridine; Liver Neoplasms; Lymphoma; Lymphoma, Non-Hodgkin; Mercaptopurine; Mice; Neoplasms, Experimental; Nitrogen Mustard Compounds; Nucleosides; Nucleotides; Purines; Research; RNA; RNA, Neoplasm; Sarcoma 180; Thioguanine; Uracil Mustard