Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.27.5 (RNase)
 17,967 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The activities of enzymes catalyzing the formation of nucleic acid precursors, nucleoside kinases, as well as of those involved in the degradation of nucleic acids, were studied in nuclei of the liver of healthy persons, human hepatomas and the liver of patients with cancer of gastrointestinal tract. The activities of thymydine kinase and uridine kinase in the human hepatoma nuclear sap were found to increase 40- to 50-fold and 120- to 150-fold, respectively, as compared to those in normal human liver. The activities of DNase and RNase in the fraction of chromatin protein of human hepatomas, on the contrary, decreased almost to zero. As to the liver of patients with cancer of gastrointestinal tract, drastic alterations in the activities of nucleoside kinases and nucleases in the direction characteristic of tumors themselves were observed. This phenomenon is regarded as a manifestation of the systemic effects of the tumor on the host.
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PMID:[Enzymes of anabolic and catabolic nucleic acid pathways in human hepatomas, in liver of healthy persons, and in liver of patients with cancer of gastrointestinal tract]. 19 26

The turnover of messenger RNA (mRNA) in two intrahepatically transplantable hepatoma (5123 and 19) and host livers of Buffalo rats was evaluated with four different approaches. [14C]Orotic acid incorporation into the rapidly labeled peak between 18S and 4S of total polyribosomal RNA was measured. In vitro RNase assay of [14C]orotic acid-labeled mRNA of polyribosomes was utilized. The decay of mRNA as reflected by disaggregation of free and membrane-bound polyribosomes at intervals after actinomycin D treatment was determined. The incorporation of [14C]orotic acid into polyadenylic acid-mRNA of free and membrane-bound polyribosomes was assayed. The results revealed that the turnover of mRNA of total, free, and membrane-bound polyribosomes was greater in the host livers than it was in the two hepatomas. In host livers the turnover of mRNA of the free polyribosomes was greater than that of the membrane-bound polyribosomes. In the two hepatomas the turnover of mRNA of free polyribosomes was at a similar rate as that of membrane bound polyribosomes. Hepatoma 19, which grow more rapidly and is less differentiated morphologically than is hepatoma 5123, appeared to have a slower turnover of mRNA than did hepatoma 5123. Measurement of RNase activity revealed greater activity in host livers than in hepatomas.
Cancer Res 1978 Jun
PMID:Turnover of messenger RNA in transplantable hepatomas and host liver of rats. 20 54

The primary structure of 18S rRNA of the Novikoff hepatoma cells was investigated. Regardless of whether the primary sequence of 18S rRNA is finally determined by RNA sequencing methods or DNA sequencing methods, it is important to identify numbers and types of the modified nucleotides and accordingly the present study was designed to localize the modified regions in T1 RNase derived oligonucleotide. Modified nucleotides found in 66 different oligonucleotide sequences included 2 m62A, 1 m6A, 1 m7G, 1m1cap3psi, 7 Cm, 13 Am, 9 Gm, 11 Um, and 38 psi residues. A number of these modified nucleotides are now placed in defined sequences of T1 RNase oligonucleotides which are now being searched for in larger fragments derived from partial T1 RNase digests of 18S rRNA. Improved homochromatography fingerprinting (Choi et al. (1976) Cancer Res. 36, 4301) of T1 RNase derived oligonucleotides provided a distinctive pattern for 18S rRNA of Novikoff hepatoma ascites cells. The 116 spots obtained by homochromatography contain 176 oligonucleotide sequences.
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PMID:Modified nucleotides in T1 RNase oligonucleotides of 18S ribosomal RNA of the Novikoff hepatoma. 20 19

Serum Ribonuclease (RNase, EC. 3. 1. 4. 22) of normal persons and of patients with chronic pancreatitis, or pancreatic cancer was determined with poly (C) as substrate. Strikingly abnormal elevations occured in the serum RNase of patients with pancreatic cancer (p less than 0.001). Average serum RNase values of 18 normal persons, 10 patients with chronic pancreatitis and 26 patients with pancreatic cancer were 92, 118, and 249 units, respectively. In patients with pancreatic cancer, we compared the RNase level with four histologic types (ductar cell adenocarcinoma, anaplastic cell carcinoma, acinar cell carcinoma, and islet cell carcinoma). Adenocarcinoma showed higher activity than the other histologic types (p less than 0.005). When we compared the serum of pancreatic cancer and pancreatic cancer tumor extract with normal serum and normal pancreas extract, strikingly different phosphocellulose chromatographic pattern were evident. The correlation of increased serum RNase levels with tumor histology and different chromatographic pattern may explain the new enzyme production in cancer patients, and have biological significance in the development of pancreatic cancer.
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PMID:Serum ribonucleases in pancreatic cancer: relation to tumor histology. 21 87

A dialysable low-molecular-weight factor capable of affecting in vitro properties of macrophages was extracted from four different mouse tumors. This factor not only modulates closely related properties of peritoneal macrophages such as spreading and migration but also inhibits lipopolysaccharde-induced tumoricidal activity of these cells. It can be extracted not only from tumor tissues but also from tumor cells grown in vitro. The appearance of this factor is unique to tumors and it is not present in detectable quantities in normal tissues. The factor from one of the tumors, Lewis lung carcinoma, was purified extensively and the partially purified factor retains all the above effects on macrophages. It is not sensitive to pronase or a mixture of bovine spleen phosphodiesterase II, E. coli alkaline phosphatase and pancreatic ribonuclease. The factor is lipid-like in character and it is soluble in both organic solvents and aqueous media. It has ionizable group(s) and is anionic at neutral pH but non-ionic under acidic conditions.
Int J Cancer 1979 Mar 15
PMID:Characteristics of a low-molecular-weight factor extracted from mouse tumors that affects in vitro properties of macrophages. 22 Jan 97

Retinoic acid-binding protein (RABP) has been detected in the nuclei of chick embryo skin and Lewis lung tumor. The nuclear binding component showed the same ligand specificity and sedimentation value as the cytosol RABP. Whereas pronase completely digested the nuclear binding component, DNase showed 40%, and RNase showed negligible digestive action. Retinoic acid binding to the nuclear RABP was completely inhibited by a mercurial, and the inhibition was reversed by dithiothreitol. The nonspecific uptake of retinoic acid by Lewis drug nuclei and chick embryo skin nuclei was inhibited up to 50% by cytosol RABP. The maximal inhibitory effect produced by cytosol RABP was after 45-min incubation. Incubation of Lewis lung tumor with [3H]retinoic acid resulted in the appearance of nuclear RABP: [3H]retinoic acid in the nuclei. The complex formed was weak, and most of the bound retinoic acid could be removed by dialysis.
Cancer Res 1979 Jul
PMID:Localization of retinoic acid-binding protein in nuclei and the nuclear uptake of retinoic acid. 22 Nov 5

We studied serum carcinoembryonic antigen (CEA) levels in 82 patients. Thirty-four of these had benign diseases while 48 had malignant diseases. Highest incidence and levels of CEA occurred in the sera of patients with pancreatic cancer and stomach cancer. In this paper we focused our particular attention on the serum CEA of 25 pancreatic cancer patients, and examined differences in serum CEA levels in relation to histologic differentiation and sites of pancreatric cancer. No statistical difference in serum CEA level was found among various histologic types and sites of the pancreatic cancer. Clinical courses of two patients with pancreatic cancer were also studied. Serial determinations of CEA levels are most useful in assessing the effect of operation or chemotherapies and are a useful indicator for differentiating pancreatic cancer from chronic pancreatitis but cannot be a conclusive factor for the diagnosis. Finally, we correlated serum CEA levels with those of RNase and confirmed a positive correlation.
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PMID:Clinical studies on carcinoembryonic antigen in pancreatic cancer. 22 3

Normal murine spleen cells were sensitized to syngeneic myeloid leukemia cells by RNA extracted from the lymph nodes and spleens of Hartley guinea pigs immunized with the murine leukemia cells. Sensitization mediated by RNA was an active process that required physiologic temperature and at least a 10-minute incubation. RNA extracted from unimmunized guinea pigs of guinea pigs immunized with normal spleen cells failed to sensitize the mouse spleen cells. Sensitization was specifically directed toward leukemia cells, whereas the spleen cells remained unreactive toward normal spleen or bone marrow cells. The sensitizing moiety was RNA itself inasmuch as it was inactivated by RNase and not by DNase or pronase. Preparations whose RNA patterns on sucrose density centrifugation gave evidence of degradation of the RNA did not sensitize normal spleen cells. These studies demonstrate that xenogeneic immune RNA can specifically sensitize normal spleen cells to syngeneic myeloid leukemia cells.
J Natl Cancer Inst 1979 Jan
PMID:Sensitization in vitro to murine myeloblastic leukemia cells by xenogeneic immune RNA. 28 68

The effect of I-RNA therapy was studied in a B16 melanoma-C57BL/6J mouse system. After having primary B16 isografts excised, mice receiving syngeneic lymphocytes incubated in vitro with specific guinea pig B16 I-RNA showed significantly improved survival as compared to control mice receiving untreated lymphocytes. This therapeutic effect was tumor specific and RNase sensitive. Significant cytotoxicity against B16 cells in vitro was consistently observed with lymphocytes prepared from B16 I-RNA treated animals, whereas lymphocytes from control animals or those treated with RNase-degraded B16 I-RNA or 3LL I-RNA had no effect. Results suggest that the combination of surgery and immunotherapy with I-RNA may be useful in preventing tumor recurrence in certain patients with cancer.
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PMID:Immunotherapy with RNA in cancer. 29 31

A clone, YS-T22, of cells from Yoshida sarcoma cell line, YSSF-212T, grown in "serum-free" culture medium produced factors stimulating differentiation of mouse myeloid leukemia cells (M1) to macrophages and granulocytes. The formation of macrophages and granulocytes was accompanied by induction of phagocytosis, locomotive activity, and lysosomal enzyme activities. The rates of induction of these differentiated phenotypes were proportional to the concentration of the factor added and the period of treatment. The factor stimulating differentiation of M1 cells was a heat-labile, nondialyzable proteinaceous substance that was inactivated by trypsin but not by ribonuclease or glycosidases. On diethylaminoethyl cellulose chromatography, the factor stimulating differentiation of M1 cells from conditioned medium of YS-T22 cells was eluted in various fractions with or without activity of the colony-stimulating factor.
Cancer Res 1979 Dec
PMID:Characterization of factors stimulating differentiation of mouse myeloid leukemia cells from a Yoshida sarcoma cell line cultured in serum-free medium. 31 74


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