Chromosomal proteins in hepatocarcinogenesis.
The chromosomal proteins of rat liver were studied by SDS-gel electrophoresis during the process of nitrosomorpholine-induced hepatocarcinogenesis, in the primary hepatomas thus obtained, and in their metastases. It was found that an increased proteolytic activity was present in liver homogenates from carcinogen-fed animals which caused differences between the nonhistone chromosomal proteins of control and carcinogen-treated livers. These differences disappeared in the presence of the protease inhibitor PMSF. In the primary hepatomas slight quantative changes were observed: an increased amount of two proteins of 43000 and 63000 daltons molecular weight, respectively, and a decrease in the histone subfraction H 1 degrees. In the metastases both quantative and qualitative differences were detected: a strong decrease in the protein bands corresponding to the contractile proteins alpha-tubulin, beta-tubulin, and actin; an increased content of the 63000 dalton protein; the appearance of new proteins of approximately 60000, 90000, and 120000 daltons molecular weight, and the complete disappearance of histone H 1 degrees.
D000818:Animals; D002868:Chromosomal Proteins, Non-Histone / Q000032:analysis*; D006657:Histones / Q000378:metabolism; D008113:Liver Neoplasms / Q000032:analysis* / Q000139:chemically induced; D008114:Liver Neoplasms, Experimental / Q000032:analysis* / Q000139:chemically induced; D008297:Male; D008970:Molecular Weight; D009362:Neoplasm Metastasis; D009603:Nitroso Compounds; D010664:Phenylmethylsulfonyl Fluoride / Q000494:pharmacology; D051381:Rats
D002868:Chromosomal Proteins, Non-Histone; D006657:Histones; D009603:Nitroso Compounds; D010664:Phenylmethylsulfonyl Fluoride