Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. Ethanol metabolism in slices or homogenates of transplantable hepatocellular carcinoma HC-252 (HC-252) was 50 to 60% of the rate found in host liver slices or homogenates when they were expressed per gram of tissue wet weight and 70 to 80% of the liver when the rates were expressed per milligram of tissue protein. At 10 mM ethanol, the activities of alcohol dehydrogenase in tumor and liver supernatants were comparable. 2. Tumor microsomes did not oxidize ethanol in the presence of a NADPH-generating system, indicating the absence of the microsomal ethanol-oxidizing system and catalase-mediated peroxidation of ethanol. The HC-252 microsomes were contaminated with catalase, and acetaldehyde production occurred in the presence of a H2O2-generating system (xanthine oxidase). The virtual absence of ethanol oxidation and drug metabolism (aminopyrine demethylase and aniline hydroxylase) in HC-252 microsomes may be due to the low activities of NADPH-cytochrome c reductase, NADPH oxidase, and NADPH-dependent oxygen uptake. 3. Microsomal oxidation of ethanol was present in Morris hepatoma 5123C, a well-differentiated tumor of intermediate growth rate, while activity was negligible in microsomes from Morris hepatoma 7288CTC, a less differentiated tumor. Microsomal NADPH oxidase was present in the well differentiated tumor 5123C but was lacking in the less differentiated tumor 7288CTC. Several microsomal, mitochondrial, and cytosolic properties of HC-252 are similar to those of Morris hepatoma 7288CTC but differ from those of the more differentiated 5123C tumor and normal liver. 4. The content of mitochondrial protein in HC-252 was only 25% that of liver, and oxygen consumption per gram of tumor was only 28% that of the liver. When corrected for the mitochondrial protein content, oxygen uptake in tumor HC-252 and liver homogenates was comparable. Isolated tumor and liver mitochondria displayed comparable State 4 and 3 rates of oxygen consumption with succinate and glutamate as substrates. The activities of the reconstituted malate-aspartate and alpha-glycerophosphate shuttles were only slightly lower in isolated HC-252 mitochondria compared to liver mitochondria, when shuttles were reconstituted with purified enzymes. 5. Antimycin inhibited alcohol metabolism,and pyruvate stimulated alcohol metabolism, much less in tumor slices than in liver slices, suggesting the presence of an augmented mitochondria-independent, cytosolic mechanism for oxidizing reducing equivalents in the tumor. These factors suggest that oxidation of NADH is the limiting factor in ethanol metabolism. Whereas, in the liver mitochondrial reoxidation is predominant, in HC-252, cytosolic reoxidation of NADH also plays a major role.
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PMID:Ethanol metabolism by a transplantable hepatocellular carcinoma. Role of microsomes and mitochondria. 13 37

Effect of BCG, coenzyme Q10, or their combination on ATPase activity in spleen lymphocytes of tumor-bearing rats was investigated in relation to changes in the content of individual coenzyme Q homologs in these cells. Contents of both coenzyme Q9 and Q10 in spleen lymphocytes significantly decreased in the late stage of Donryu rats bearing Sato lung carcinoma. Oligomycin-sensitive ATPase activity in spleen lymphocytes was also significantly depressed in this stage. The depressed, oligomycin-sensitive ATPase activity was significantly recovered by a 3-time intramuscular administration of coenzyme Q10 emulsified with ethanol and saline, and the decreased contents of coenzymes Q9 and Q10 were slightly restored by this treatment. This enzyme activity was also significantly recovered by an intravenous administration of BCG, and was elevated more by the combined treatment with BCG and the emulsified coenzyme Q10. These results suggest that the combined treatment with BCG and emulsified coenzyme Q10 can contribute to the improvement of the depressed bioenergetics in lymphocytes of tumor-bearing animals, and that this combined effect of BCG and emulsified coenzyme Q10 might be based on the combination of their individual activating effect on lymphocytes.
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PMID:Combined effect of BCG and coenzyme Q10 on ATP-ase activity and coenzyme Q content in spleen lymphocytes of tumor-bearing rats. 15 9

Insulin has been isolated from pancreases of the Syrian hamster and from a transplantable islet-cell tumor of the hamster. Acid/ethanol extraction, ether precipitation, ion exchange and gel filtration chromatography gave preparations of suitable purity for structural studies. Using trypsin cleavage, automatic Edman degradation and manual Edman degradation, a complete sequence of the pancreatic insulin B chain was determined. By automatic Edman degradation, the amino-terminal 10 residues of the pancreatic A chain were assigned and the sequence of carboxy-terminal eleven residues could be deduced by homology to other mammalian and avian insulins. The sequence assigned to hamster insulin A chain is identical to that of the rat, mouse and spiny mouse. The sequence of hamster insulin B chain is identical to rabbit and spiny mouse B chain. In terms of protein evolution, hamster insulin thus appears to occupy an intermediate position between rabbit and rat insulins. Amino acid composition, tryptic peptide composition and partial sequence analysis of the hamster tumor insulin showed no differences from hamster pancreatic insulin.
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PMID:A comparison of the structure of hamster pancreatic insulin and insulin extracted from a transplantable hamster islet-cell carcinoma. 17 43

It was previously reported that the properties of alcohol dehydrogenase of a rat hepatocellular carcinoma (Becker H-252), a tumor of intermediate growth rate, were different from those of the liver enzyme, suggesting different isozymes. To determine whether the degree of differentiation affected the isozyme of alcohol dehydrogenase, a fast-growing, poorly differentiated tumor and one that is well differentiated and of intermediate growth rate were studied. Alcohol dehydrogenase from Morris hepatoma 7288ctc, a fast-growing, poorly differentiated tumor, had properties similar to those found with the Becker-H-252 tumor, including a high Km for ethanol and acetaldehyde and the absence of substrate inhibition. By contrast, alcohol dehydrogenase from the well-differentiated Morris hepatoma 5123C had properties similar to those of the liver enzyme. Thus, alcohol dehydrogenase is another example of an enzyme the isozyme composition of which changes with neoplastic de-differentiation. Further studies, including gel electrophoresis, substrate specificity patterns, and interaction with antibodies to alcohol dehydrogenase, are required to determine the factors responsible for the biochemical defect that occurs at the molecular level during carcinogenesis and whether the alcohol dehydrogenase isozymes in the Becker H-252 and Morris 7288ctc hepatomas are identical. A survey of several normal rat tissues revealed that only the stomach contains this unique isozyme of alcohol dehydrogenase.
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PMID:Kinetic properties of alcohol dehydrogenase in hepatocellular carcinoma and normal tissues of rat. 17

In agreement with data previously reported (Yalow and Berson 1973), after gel filtration of acid-ethanol extracts of islet cell adenomas (performed in 3 M acetic acid) 1.4% to 1.8% of total immunoreactive insulin (IRI) eluted ahead of proinsulin. The high-molecular IRI (HM-IRI) was, however, found to be heterogenous in size and consisted of at least three components, the major one having an estimated molecular weight of about 50,000. Under certain conditions, HM-IRI was partially dissociated into proinsulin- and insulin-like components. We conclude that HM-IRI does not represent a precursor of proinsulin and insulin, but probably a self-association product of the peptides or an association of insulin and proinsulin to other proteins extracted from tumor tissue.
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PMID:High-molecular IRI (big, big insulin) in islet cell adenoma. 17 31

On gel filtration of acid-ethanol extracts from three pancreatic beta-cell adenomas 1.4% to 1.8% of total immunomeasurable insulin (IMI) eluted ahead of proinsulin. This high molecular IMI was resolved into three components. The presence of urea in the dilute acetic acid solutions of extracted tumor tissue did not influence the pattern of gel filtration. High molecular IMI dissolved in dilute acetic acid showed to be stable if immediately rechromatographed, but a partial dissociation to insulinlike and proinsulinlike components (ILC and PLC) was found if rechromatography was performed after 48 h of incubation. Mainly ILC and PLC were found on rechromatography provided high molecular IMI was dissolved and incubated briefly in 0.04M phosphate buffer, pH 7.4. It proved improbable that the proteolytic action of some protein being extracted with the hormones caused a splitting of high molecular IMI at pH 7.4. We conclude from our findings that the components of high molecular IMI are not precursors of proinsulin and insulin but are either self-associated products of the hormones or associations of insulin and proinsulin to other proteins extracted from insuloma tissue.
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PMID:Chromatographic heterogeneity of insulin extracted from insulomas. 23 76

The authors studied the factors which favour necrosis after curietherapy, in a series of 82 patients with epithelioma of the oral cavity and a previous series of 280 cases. The principal factor is the size of the tumor. The other factors (macroscopic appearance, dose, quantity of radioactive material, degree of inhomogeneity, distance between the lines, association with external irradiation), are or only moderate importance, as shown by the variations observed, though they are difficult to evaluate in an exact manner, partly for methodological reasons. The frequency of necrosis of bone tissue is directly relaxed to the number of radioactive lines in contact with the maxilla. Alcohol and tabacco abuse have a definite influence but this cannot be calculated. In conclusion, therefore, it would appear possible to reduce the frequency of necrotic lesions by reducing the tumoral size by curietherapy, by applying no more than 2 lines in contact with the mandible for bony necrotic lesions, and by stopping the abuse of alcohol and tobacco.
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PMID:[Factors favouring necrosis after curietherapy for oral cavity epitheliomas (author's transl)]. 28 54

Alcohol appears to exert a depressive effect on host immunity. Animal models useful in studying immune responsiveness in cancer research are discussed, which could be of value in studying the effect of alcoholism. Allogeneic tumor grafts are poorly rejected in immunosuppressed mice. Of the four major cellular elements of the immune system, the macrophage appears to have a critical role in immune surveillance. Several conditions occur which abrogate or restrict the tumoricidal activity of macrophages. Stress induced by physical restraint results in depressed macrophage activation. The tumoricidal activation induced in macrophages by interferon was markedly depressed in the presence of the corticosteroids, hydrocortisone, prednisone, and dexamethasone. In addition, prostaglandins (PGE1 and PGE2) also were found to decrease interferon activation of macrophages. Since immune deficiency is a trait of alcoholism and cancer, animal models with defined, measurable, immunological parameters would be useful in studying the effect of alcohol on cellular immunity.
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PMID:Animal models in cancer research which could be useful in studies of the effect of alcohol on cellular immunity. 57 62

Because staphylococcal protein A binds all the known subclasses of mouse IgG except IgG1, ethanol-fixed staphylococci were used as an adsorbent to prepare IgG1 fractions of anti-BALB/c alloantibody-containing globulins and normal globulins of the same strains. The loss of more than 99% of the IgG2 as a result of this adsorption was demonstrated by immunodiffusion. The IgG1 fractions of C3H and CBA anti-BALB/c globulins were tested for their effect on growth of the BALB/c plasmacytomas MOPC-315 and MOPC-460 in C3H and CBA mice by incubation with the tumor cells before transplantation and by injection periodically thereafter into the hosts. With alloantibody-containing globulins that showed slight enhancement of growth of these tumors, or none, the IgG1 preparations caused considerable enhancement of tumor growth. Control preparations of normal C3H or CBA globulins, or IgG1 fractions similarly prepared from the normal globulins, showed no enhancing effect on the growth of these tumors.
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PMID:Enhancement of growth of allogeneic mouse tumor by the IgG1 fraction of alloantibody preparations. 62 14

Cytostatic effects and some pharmacological properties of a new metabolic inhibitor "3-oxauracil" were studied. The cancerostatic effect was examined on 7 experimental tumors in mice and on two types of tumors in rats. After the i. p. application of 20 mg/kg, there was both a statistically significant decrease of tumor weight and increase of animals' survival time in NK lymphoma of mice. Significant changes in one of both parameters followed occured in all experimental tumors after the i. p. application but only in the Krebs ascitic carcinoma after the oral application of "3-oxauracil". The acute toxicity of the substance in water was 322 mg/kg i. p. and 850 mg/kg p. o. The ethanol solutions were more toxic. The distribution of the 3H- and 14C-labeled substance was followed up in blood, urine, liver, brain and kidney. After the p. o. application, the radioactivity peak was reached after 2 hr in blood and high radioactivity levels were found in kidney followed by brain and liver. 96 hr after the drug was applicated perorally, only 60% of radioactivity was found in urine.
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PMID:Some cytostatic and pharmacological properties of 2,3-dihydro-1,3-6H-oxazine-2,6-dione ("3-oxauracil"). 69 3


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