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)

Plasma and prostatic fluid from man, dog, and baboon were measured for carcinoembryonic antigen (CEA) by a radioimmunoassay technique. No CEA was detected in plasma, prostatic fluid, or seminal fluid in 12 dogs and three baboons. Elevated CEA (less than 2.5 ng/ml) was found in 13 of 20 human prostatic fluids. It was inferred that there was no immunologic cross-reactivity of CEA among man, dog, and baboon. CEA has been isolated and purified from liver tumors. Biochemical studies reveal that CEA consists of 60 percent carbohydrate and 40 percent protein. It contains the following carbohydrates: fucose, mannose, galactose, sialic acid, N-acetylglucosamine, and a small amount of N-acetylgalactosamine. The following amino acids were found in CEA: lysine, histidine, arginine, aspartic acid, threonine, serine, glutamic acid, proline, glycine, alanine, valine, emthionine, isoleucine, leucine, tyrosine, phenylalanine, and cysteine. The amino acid sequence (first 30 amino acids) of the N-terminal has been determined. The N-terminal amino acid was lysine. Using this study as a model, other tumor antigens from prostatic tumor tissues are being investigated. The acid phosphatase isoenzyme from prostatic tissue was also studied. After a series of purifications, two chromatographic fractions were obtained. Treatment with neuraminidase removed the sialic acid content of the molecule, changed the isoelectric focusing patterns, and abolished the chromatographic heterogeneity. Sedimentation studies indicated a molecular weight of about 100,000. Biochemical studies showed that prostatic acid phosphatase isoenzyme is a glycoprotein which consists of 7 percent carbohydrate and 93 percent protein. It contains fucose, galactose, mannose, sialic acid, N-acetylglucosamine, and the following amino acids: aspartic acid, threonine, serine, glutamic acid, proline, glycine, alanine, valine, methionine, isoleucine, leucine, tyrosine, phenylalanine, lysine, histidine, arginine, tryptophan, and cysteine. An antiserum to this purified prostatic acid phosphatase isoenzyme is being prepared in animals.
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PMID:Tumor antigen and acid phosphatase isoenzyme in prostatic cancer. 4 19

A glycoprotein has been isolated from the colonic lavages of healthy individuals that is immunologically equivalent to carcinoembryonic antigen purified from tumor tissue. The NH2-terminal sequence of the glycoprotein from normal colon lavages is Lys-Leu-Thr-lle-Glu-Ser-Thr-Pro-Phe-(Asn)-Val-Ala-Glu-Gly-Lys-Glu-Val-(Leu,lle)-(Leu,lle)-(Leu,lle)-Val-(His,Arg?)-?-(Leu,lle). This is homologous to the NH2-terminal sequence of 23 of the first 24 amino acids of carcinoembryonic antigen isolated from tumor tissue.
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PMID:Amino-terminal sequence of a carcinoembryonic antigen-like glycoprotein isolated from the colonic lavages of healthy individuals. 7 56

Alkaline phosphatase (ALP) components in extracts of seven malignant and eleven benign ovarian tumors were characterized using the criteria of electrophoretic mobility before and after neuraminidase treatment, heat stability, L-phenylalanine inhibition and reactivity against antiplacental ALP antiserum. Seven of the eighteen tumors had ALP components which most closely resembled the ALP isoenzyme normally found in placenta and were clearly distinguished from all other tissue ALPs. The proportion of tumors with the placental-like ALP in the malignant group (five out of seven) was significantly greater than the proportion in the benign group (two out of eleven). The fraction (78%) of the malignant tumors with the isozyme represents a larger percentage than has previously been found by examination of cancer patients' sera. The electrophoretic mobilities of the placental-like ALPs in the tumors were in no case identical to the mobilities of any of the six common placental ALP phenotypes. The tumor ALPs may thus be determined by rare variant alleles at the ALP locus, or alternatively, the enzyme molecules may have been subject to structural modification. At least two of these tumors contained an electrophoretically slow. heat-stable, leucine-sensitive ALP, which may correspond to what has been termed the D-variant of placental ALP found in some other tumors.
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PMID:Placental-like alkaline phosphatase in malignant and benign ovarian tumors. 7 47

Extracts of rat anterior and intermediate-posterior pituitary were fractionated by sodium dodecyl sulfate polyacrylamide gel electrophoresis and assayed for immunoactive ACTH and endorphin. In both lobes the major forms of immunoactive ACTH have apparent molecular weights of 31,000 (31K), 20--21K, 14K, and 4.5K, and the major forms of immunoactive endorphin have apparent molecular weights of 31K (coincident with the peak of immunoactive ACTH), 13K (a betaLPH-like peptide), and 3.5K (a beta-endorphin-like peptide). However, the quantitative distribution of immunoactivity among the various forms differs greatly between the lobes. Assays using an extreme COOH-terminal ACTH antiserum indicate that the 31K ACTH/endorphin molecule in rat anterior and intermediate pituitary is similar to the pro-ACTH/endorphin molecule from mouse pituitary tumor cells. A radioimmunoassay that is specific for the NH2-terminal non-ACTH, nonendorphin segment (referred to as 16K fragment) of the mouse pro-ACTH/endorphin molecule was used to assay extracts of rat pituitary. In addition to detecting material at 31K and 20--21K, the 16K fragment radioimmunoassay detects significant amounts of cross-reactive material with an apparent molecular weight of 16K in extracts of both lobes. This result also suggests that the structure and processing of the rat 31K ACTH/endorphin molecule is similar to that of mouse tumor cell pro-ACTH/endorphin. Cell suspensions were prepared from the anterior and intermediate lobes of the rat pituitary and maintained in culture for a 24-h period. The isolated cells from both lobes incorporate [3H] phenylalanine into immunoprecipitable ACTH- and endorphin-containing molecules. By sequential immunoprecipitation with ACTH and endorphin antisera, it is possible to demonstrate directly that a single molecule (31K ACTH/endorphin) has antigenic determinants for both ACTH and endorphin. Significant amounts of 31K ACTH/endorphin are released into the culture medium by isolated anterior lobe and intermediate lobe cells. The isolated intermediate lobe cells synthesize and secrete relatively large amounts of a beta-endorphin-like molecule; the isolated anterior lobe cells secrete significant amounts of both a betaLPH-like molecule and a beta-endorphin-like molecule. These same quantitative differences between anterior and intermediate lobe tissue were observed in immunoassays of extracts of the separated lobes and probably reflect differences in the processing of the common precursor. The isolated anterior lobe cells can be stimulated to release increased amounts of immunoprecipitable ACTH and endorphin by incubation with a cyclic AMP analog and a phosphodiesterase inhibitor.
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PMID:Existence of a common precursor to ACTH and endorphin in the anterior and intermediate lobes of the rat pituitary. 8 77

beta2-Microglobulin has been synthesized in vitro by using a rabbit reticulocyte lysate system and mRNA from the mouse tumor cell line EL4. The molecule is synthesized as a precursor with an NH2-terminal extension of 19 amino acids: Ser-X-Ser-Val-X-Leu-Val-Phe-Leu-Val-Leu-Val-Ser-Leu-X-Gly-Leu-Tyr-X. The processing and segregation of this peripheral membrane protein are directly comparable to those of secretory proteins and integral membrane proteins: addition of dog pancreas microsomal membranes during translation caused conversion to the processed chain, but addition of membranes after synthesis did not; only the processed chain sedimented with the membrane vesicles and was protected from proteolysis by the vesicles; and processing of nascent beta 2-microglobulin was blocked by competitive inhibitors that prevent processing and segregation of secretory and integral membrane proteins. These results suggest that the signal sequences of secretory proteins, integral membrane proteins, and peripheral membrane proteins have a common function and a common receptor on the cytoplasmic face of dog pancreas microsomal membranes. This system also provides a means for studying in vitro the expression and function of the major histocompatibility antigens that are associated with beta 2-microglobulin on cell surfaces.
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PMID:Cell-free synthesis and segregation of beta 2-microglobulin. 9 Nov 68

Two cases of liver metastases from gastric carcinoma are described in which the simultaneous occurrences of alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA) and carcinoplacental alkaline phosphatase (CPALP) were demonstrated in the sera and tumor tissues. AFP was detected not only in the tumor tissues but also in the liver tissue adjacent to the tumor, while the other 2 carcinoembryonic proteins were not detected in the non cancerous liver tissues. The characteristics of CPALP in Case 1 were almost similar to the Nagao isoenzyme, based on enzyme tests involving L-leucine, L-phenylalanine and EDTA inhibitions, heat-stability and Michaelis constant, except for electrophoretical slower moving, while that in Case 2 were identical to variant type CPALP (Warnock).
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PMID:Carcinoembryonic proteins in gastric carcinoma metastatic to the liver. 9 60

The effects of energy deprivation and low or high dietary protein levels upon lymphocyte transformation of spleen cells from syngeneic tumor-bearing and control mice were studied in a murine model of malignant melanoma. Both T- and B-lymphocyte transformation were significantly stimulated by the presence of a growing melanoma. T-cell responses however, were dependent only upon dietary protein concentrations, not the level of energy intake; whereas, the converse was true for B cells. Moreover, mice fed stock diet had the lowest response to mitogens of all diets tested. Except for mice receiving a 15% casein diet, tumor weights were generally not affected by level of intake or the amount of dietary protein. Others have demonstrated that melanoma cells have a greater need for tyrosine or phenylalanine than other tumor cells; thus we hypothesized that lymphocyte transformation may be depressed by relatively low phenylalanine or tyrosine levels in the diet when protein intakes are limited by either a low dietary concentration a restricted intake of a diet containing adequate protein, or both.
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PMID:The influence of dietary protein concentration and energy intake on mitogen response and tumor growth in melanoma-bearing mice. 10 97

The tyrosinase activity in two sucrose gradient isolated melanosome fractions from a melanotic hamster melanoma was found to increase after alpha-chymotrypsin treatment. The enhancement in tyrosinase activity had its maximum at a concentration of 1 mg/ml alpha-chymotrypsin after 120 min incubation at 37 degrees C. No direct activating effect of alpha-chymotrypsin was found either on the soluble tyrosinase fraction from freshly prepared untreaed whole-tumor homogenate or on purified mushroom tyrosinase. The activating effect of alpha-chymotrypsin upon the melanosome tyrosinase is believed to be due to the endopeptidic hydrolysis of the--CO--NH--bound existing between tyrosinase and tyrosine and phenylalanine residues in the melanin molecule. Although alternative interpretations are not excluded, the observed enhancement in tyrosinase activity after alpha-chymotrypsin treatment of melanosomes might indicate the existence of an "enzyme liberating" mechanism in the melanosomes.
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PMID:Chymotrypsin activation of melanosome tyrosinase in hamster melanotic melanoma. 11 73

The effects of estrogens on transport and incorporation of amino acids into the R3230AC mammary adenocarcinoma were studied in vivo and in vitro. Dissociated tumor cells from ovariectomized rats, like those from diabetic rats, displayed elevated transport of proline, representing entry by the A system; transport of phenylalanine (L system) was unaltered, as was glucose transport and its utilization. Administration of estradiol valerate decreased the entry of proline into tumor cells from intact, diabetic, or ovariectomized animals; the response to the steroid hormone was greater in ovariectomized or diabetic rats compared to intact animals. The time course of the effects of estrogen treatment was examined in diabetic rats. By 72 hr, transport of both proline and leucine was significantly decreased; incorporation of leucine into proteins and uridine into RNA was significantly reduced by 24 hr after injection of estradiol valerate. The effects of estrogen in vivo to reduce transport of amino acids and their incorporation into proteins appeared to correlate with the reduced tumor growth observed. Experiments were performed to examine the effects of 17 beta-estradiol in vitro on amino acid transport into dissociated cells from ovariectomized or diabetic rats. Under these experimental conditions, 17 beta-estradiol (10(-6)M) inhibited proline transport with little or no effect on leucine transport in cells from ovariectomized rats; in cells from diabetic rats, proline transport and leucine incorporation were significantly reduced by estradiol, whereas phenylalanine transport was slightly inhibited (approximately 20%). The effect of estradiol in vitro was also manifest in tumor cells obtained from diabetic rats treated in vivo with estradiol valerate; estradiol in vitro caused a further reduction in proline transport but not in leucine transport, results that imply some specificity to the action of estrogen on the A system. Since we had earlier shown that insulin action on transport in these tumor cells were directed towards the A system, we examined the effects of insulin, estradiol, and their combination in vitro on proline and leucine transport. Insulin (10(-8) M) stimulated proline transport; 17 beta-estradiol, at a selected lower level of 10(-8) M, inhibited proline transport. When both were added in vitro, estradiol (10(-8 M) was capable of significantly reducing the insulin (10(-8) M)-induced increase in proline transport. Leucine transport was not altered in any of these experiments. Together, these data suggest that estrogens are capable of inhibiting amino acid transport into the R3230AC mammary carcinoma, an effect that is compatible with reduced tumor growth. The possible relationship of estrogen and insulin at the level of amino acid transport remains to be elucidated.
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PMID:Effects of estrogen to alter amino acid transport in R3230AC mammary carcinomas and its relationship to insulin action. 15 4

We have previously reported that from 350 amino acid (A-A) derivatives five were selected after the primary in vivo and in vitro screening tests. The five compounds which were found to possess potential antitumor activity against Ehrlich ascites carcinoma are as follows: beta-naphthalene-sulfonyl-DL-tryptophan (A-91), beta-naphthyl-aminomethyl-gamma-aminobutyric acid (A-144), N-ethylcarbaminomethyl-L-isoleucine (A-145), n-9-fluorenylactyl-L-phenylalanine (A-192), and N-propoinyl-L-valine (A-195). The effect on life prolongation and tumor growth of these selected A-A derivatives against various types of tumors, including ascites and solid tumors in mice and ascites hepatomas in rats, was examined. A-A derivatives were administered once daily 3 consecutive days starting 24 hours after tumor implantation. Experimental results showed that among the five A-A derivatives possessing considerable activity against Ehlich carcinoma, A-144 and A-145 were found to be more effective than chromomycin A and showed activity similar to that of cyclophosphamide against ascites Sarcoma 180. A-A derivatives showed slight antitumor activity against SR61 and L1210 leukemias. In rat ascites hepatoma, such as AH13, AH7974, AH60C, and Yoshida sarcoma, only A-145 showed a significant prolongation of the lifespan in the control groups. The five selected A-A derivatives significantly inhibited the growth of Nakahara-Fukuoka sarcoma and solid Sarcoma 180. These findings indicate that among the five A-A derivatives, A-15 appeared to be the most active against ascites and solid tumors.
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PMID:Antitumor activity of selected amino acid derivatives against various tumor systems. 16 35


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