ABSTRACT
The incidence of somatic mutagenesis of p53 oncosuppressor protein in malignant tumors of the stomach and genetic polymorphism of p53 were studied in patients with stomach cancer on DNA samples isolated from tumor tissues obtained during surgery. The incidence of Pro/Pro genotype increased in the patients, while the percentage of Arg/Pro heterozygotes was markedly lower compared to long-living persons without cancer. The incidence of p53 somatic mutations in exons 5, 7, 8 was 70.8%; multiple mutations were detected in half of the examined patients. The relationship between the intensity of p53 mutagenesis and histological structure of the tumor was detected. The contribution of p53 genetic status to the risk of stomach cancer can be more effectively evaluated on DNA samples isolated from not only tumor cells, but also from normal tissues. The effects of epigenetic factors determining the intensity of somatic mutagenesis of p53 in tumors should be taken into account.
Subject(s)
Genes, p53 , Mutation , Stomach Neoplasms/genetics , Adult , Aged , Aged, 80 and over , Base Sequence , Case-Control Studies , Codon/genetics , DNA, Neoplasm/genetics , Epigenesis, Genetic , Humans , Middle Aged , Polymorphism, GeneticABSTRACT
The resistance of irradiated mice to bone marrow grafts treated with RNA from the liver of syngenic, allogenic, or xenogenic (rat) species was studied. Syngenic recipients developed resistance to grafts treated with allogenic RNA. The resistance to allografts increased after treatment with xenogenic RNA, whereas treatment of allo- and xenografts with syngenic RNA facilitated their take.
Subject(s)
Bone Marrow Cells/drug effects , Bone Marrow Transplantation , Graft Survival , RNA/pharmacology , Whole-Body Irradiation , Animals , Bone Marrow Cells/metabolism , Graft vs Host Reaction , Male , Mice , Mice, Inbred A , Mice, Inbred BALB C , Mice, Inbred Strains , RNA/genetics , RNA/immunology , RNA/isolation & purification , Rats , Rats, Wistar , Transplantation, Heterologous , Transplantation, HomologousSubject(s)
Carcinoma/metabolism , Gastric Mucosa/metabolism , Neoplasm Proteins/biosynthesis , Stomach Neoplasms/metabolism , Carcinoma/pathology , Cell Transformation, Neoplastic/metabolism , Gastric Mucosa/pathology , Humans , Magnesium/metabolism , Molecular Weight , Neoplasm Proteins/metabolism , Peptide Biosynthesis , Peptides/metabolism , Phosphoproteins/biosynthesis , Phosphoproteins/metabolism , Phosphorylation , Stomach Neoplasms/pathology , Tumor Cells, CulturedABSTRACT
Synthesis and glycosylation of larval salivary gland secretory proteins of Chironomus thummi were analyzed with respect to cell specific differences in the Balbiani ring (BR) pattern and glycoprotein composition of secretion formerly detected by histochemical staining procedures. In the secretion of a special cell type in salivary glands, which is characterized by the appearance of an additional BR, and additional polypeptide with a relative molecular weight (Mr) of 160 kD was found differing in its antigenic properties and tryptic fingerprint pattern from main cell secretion proteins. This so-called ssp-160 component is preferentially synthesized and glycosylated in the special cells. In the same cells, both the synthesis and glycosylation of all other major secretory proteins was found to be diminished or even repressed. In contrast to the conspicuous cell-specific differences at the level of protein synthesis. RNA analyses show the prominent synthesis of 75S RNA in both main and special cells and gave no clear indication of the synthesis of a smaller RNA fraction as expected from the size of ssp-160 component.--These and further data on synthesis and properties of secretory proteins as well as expression of BR DNA are discussed with regard to the assumption that at least some of the eight major secretory polypeptides are coded for by BR DNA. The BR gene(s) might have originated by manifold duplications and modifications of short repetitive prototype DNA sequences, which are coordinatively expressed.
