Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.1 (alkaline phosphatase)
 47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of 5-bromo-2'-deoxyuridine (BrdUrd) and dibutyryl cyclic AMP (Bt2cAMP) on the expression of the placental isoenzyme of human alkaline phosphatase was examined in BeWo choriocarcinoma cells. By using a combination of specific immunoprecipitation and polyacrylamide-gel electrophoresis of cells labelled either metabolically with [35S]methionine or cell-surface-labelled with 125I, both BrdUrd (5 micrograms/ml) and 1 mM-Bt2cAMP were shown to result in the enhanced accumulation of a specific protein. This protein has immunochemical identity and co-electrophoreses with placental alkaline phosphatase in two-dimensional gels. These results clearly demonstrate that the induction of placental alkaline phosphatase activity in choriocarcinoma cells treated with these agents is a consequence of the accumulation of specific enzyme protein rather than of altered catalytic activity.
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PMID:The effect of bromodeoxyuridine and dibutyryl cyclic AMP on the induction of placental alkaline phosphate in human choriocarcinoma cells. 627 41

Placental alkaline phosphatase activity and immunoreactivity were inhibited in a parallel fashion in choriocarcinoma cells by tunicamycin, a protein glycosylation inhibitor. Tunicamycin suppressed placental alkaline phosphatase biosynthesis in addition to inhibiting protein glycosylation in general. An anti-placental alkaline phosphatase-precipitable polypeptide of 58,000 daltons was formed in the presence of this antibiotic. The 58,000-dalton polypeptide had a degradation rate similar to that of the glycosylated phosphatase monomer from control cultures. Tunicamycin suppressed placental alkaline phosphatase mRNA activity leading to the observed decrease in biosynthesis.
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PMID:Suppression of placental alkaline phosphatase biosynthesis by tunicamycin. 651 84

5-Bromo-2'-deoxyuridine (BrdUrd) stimulated the biosynthesis and hence increased the activity of placental alkaline phosphatase in choriocarcinoma cells. While BrdUrd had no effect on the rate of degradation or processing of placental alkaline phosphatase, it increased the rate of phosphatase synthesis. The stimulation of enzyme activity could be completely accounted for by the increase in alkaline phosphatase protein. Both control and BrdUrd-induced cells contained polypeptides of 61,500 and 64,500 Da, identified as the precursor and fully processed forms of placental alkaline phosphatase monomer. The half-life of this enzyme monomer in both control and BrdUrd-treated cells was estimated to be 36 h. BrdUrd induced a specific increase in the placental alkaline phosphatase mRNA leading to the observed enhancement of biosynthesis. The continued rise in alkaline phosphatase biosynthesis in BrdUrd-induced cells following BrdUrd removal indicated that this analog acted by incorporation into DNA.
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PMID:5-Bromo-2'-deoxyuridine induces placental alkaline phosphatase biosynthesis in cultured choriocarcinoma cells. 654 61

Placental alkaline phosphatase activity was induced in choriocarcinoma cells by sodium butyrate. Butyrate stimulated de novo synthesis of the enzyme and the increase in phosphatase activity could be completely accounted for by the increase in phosphatase protein: the increases in placental alkaline phosphatase immunoactivity and placental alkaline phosphatase biosynthesis as measured by incorporation of the radioactive precursors, L-[35S]methionine, [3H]mannose, and [3H] glucosamine were similar to the increase in phosphatase activity. Sodium butyrate increased the rates of placental alkaline phosphatase biosynthesis but had no effect on the rate of placental alkaline phosphatase degradation or processing. Both control and butyrate-induced cells contained polypeptides of 61,500 and 64,500 apparent molecular weights that were identified as the precursor and fully processed forms of the placental alkaline phosphatase monomer, respectively. Further, processing of the 61,500-dalton polypeptide to the 64,500-dalton polypeptide involved the incorporation of additional glucosamine and N-acetylneuraminic acid moieties. Gel electrophoresis of anti-placental alkaline phosphatase-precipitable polypeptides from an in vitro protein-synthesizing system directed by RNA isolated from control or butyrate-induced cells demonstrated that sodium butyrate induced the synthesis of placental alkaline phosphatase mRNA. Our data indicate that sodium butyrate induces the specific transcription of the placental alkaline phosphatase gene.
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PMID:Induction of placental alkaline phosphatase biosynthesis by sodium butyrate. 669 79

Polypeptides of 61,500 and 64,500 apparent molecular weights were the precursor and fully processed forms of placental alkaline phosphatase monomer synthesized by choriocarcinoma cells in vivo. [3H] Mannose was incorporated into both polypeptides whereas [3H] glucosamine was incorporated mainly into the 64,500-dalton polypeptide, suggesting processing by the addition of glucosamine moieties. In the absence of microsomal membranes, choriocarcinoma mRNA directed the cell-free synthesis of the preprotein form of alkaline phosphatase monomer of apparent Mr = 60,000. The unglycosylated monomer had an apparent Mr = 58,000. In the presence of microsomal membranes, the 60,000-dalton polypeptide was processed to a polypeptide of apparent Mr = 61,500, comigrating with the precursor form of alkaline phosphatase monomer.
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PMID:Biosynthesis and processing of placental alkaline phosphatase. 683 75

The alkaline phosphatase activity expressed by JAR choriocarcinoma cells was compared to the placental isoenzyme of human alkaline phosphatase by several criteria. JAR cell alkaline phosphatase was similar to the placental isoenzyme with respect to heat and urea stability and sensitivity to most inhibitors, but it differed significantly from placental alkaline phosphatase in its sensitivity to L-phenylalanylglycylglycine. In contrast to the serum form of placental alkaline phosphatase, the JAR cell enzyme was highly hydrophobic as determined by octyl agarose chromatography and appeared to be larger than the placental isoenzyme based on gel filtration and polyacrylamide gel electrophoresis. The slowly migrating hydrophobic JAR cell activity could be converted into a fast-migrating hydrophilic form similar to the serum placental isoenzyme by treatment with trypsin-like proteases. Conversion to the hydrophilic form was accompanied by a decrease in subunit molecular weight from 68,000 to 66,000, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of 33P-labeled enzyme. Peptide mapping of the 33P-labeled molecules by limited proteolysis in the presence of sodium dodecyl sulfate showed JAR cell alkaline phosphatase to be closely related to the placental isoenzyme with respect to primary structure. However, placental alkaline phosphatase appeared to be richer in sialic acid residues than was the JAR cell enzyme. We conclude that JAR cells produce a form of placental alkaline phosphatase that contains a hydrophobic region not associated with the free serum enzyme and that the tumor cell enzyme is modified or processed differently than is the enzyme found in the term placenta.
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PMID:Altered form of placental alkaline phosphatase produced by JAR choriocarcinoma cells in culture. 719 43

Experimental chemotherapy with choriocarcinoma transplanted in nude mice has been studying to improve the prognosis of drug resistant choriocarcinoma. In this paper the characteristics of transplanted tumors were presented. Two tumors, CC-HM-I (HM) and CC-I-JCK (JCK), were used. The characteristics of the tumors were studied in macroscopical findings, histological findings, growth curves, DNA amount analysis, LDH activity, alkaline phosphatase activity, and their isozyme patterns. Both tumors well maintained the characteristics of original and/or the beginning ones. Some differences between two tumors were pointed out. In morphology, HM was yellowish and hard tumor and the growth rate was rather slow. While, JCK was dark and soft tumor and contained a lot of bleeding and necrotic tissue. Its growth rate was quick and all of nude mice with JCK died of tumors around 50 days after transplantation. The serum level of HCG of HM was 75.8 +/- 2.8 ng/ml/g tumor and that of JCK was 117.4 +/- 6.2 ng/ml/g tumor. The good correlation between the tumor weight and the serum level of HCG was obtained in both groups. The activities of LDH and alkaline phosphatase in the tissues of JCK were about 3 times as higher as the one of HM. It was confirmed that the transplanted choriocarcinoma in nude mice was useful model for the study the nature of human choriocarcinoma and it will contribute to the establishment of the rational chemotherapy for drug resistant choriocarcinoma.
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PMID:[Characteristics of human choriocarcinoma transplanted in nude mice (author's transl)]. 719 34

BeWo choriocarcinoma cells synthesize two alkaline phosphatase isoenzymes: germ-cell alkaline phosphatase and tissue-unspecific alkaline phosphatase. We have made use of the differential heat-stabilities of these two isoenzymes to study the induction of germ-cell alkaline phosphatase by sodium butyrate and cyclic AMP (cAMP). Sodium butyrate causes a large induction of germ-cell alkaline phosphatase activity (approx. 35-fold after 96 h) after an initial lag period of 12-24 h. We showed that butyrate increases germ-cell alkaline phosphatase mRNA. Dibutyryl cAMP also induces germ cell alkaline phosphatase (approx. 2.5-fold after 96 h). When optimal concentrations of butyrate and dibutyryl cAMP were added simultaneously to cells, they caused a synergistic induction of activity. This suggested that these compounds use separate mechanisms to induce germ-cell alkaline phosphatase activity and that it is the cAMP moiety of dibutyryl cAMP that induces enzyme activity. This was confirmed by the use of two additional cAMP analogues, 8-(4-chlorophenylthio) cAMP and 8-bromo cAMP, and of two compounds, 3-methyl-1-isobutylxanthine and cholera toxin, which raise the endogenous concentration of cAMP. All four compounds caused a 2-fold increase in enzyme activity. Treatment of cells with 8-(4-chlorophenylthio) cAMP, 8-bromo cAMP and cholera toxin increased germ-cell alkaline phosphatase mRNA between 2- and 7-fold. These data suggest that this alkaline phosphatase isoenzyme is regulated at the level of its mRNA by cAMP, in a manner distinct from that of butyrate.
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PMID:Induction of germ-cell alkaline phosphatase by butyrate and cyclic AMP in BeWo choriocarcinoma cells. 750 59

Treatment of the cultured human breast-cancer cells BC-M1 with dexamethasone induced a placental-type alkaline phosphatase (ALP). Both the ALP activity and the mRNA level in the cells were increased. The induction of ALP activity by dexamethasone was time- and dose-dependent. The accumulation of ALP mRNA was inhibited by both actinomycin D and cycloheximide, indicating that its induction is a complex event and may involve other regulatory proteins. Retinoic acid showed opposing effects with dexamethasone on the expression of alkaline phosphatase. Retinoic acid (RA) and phorbol 12-myristate 13-acetate also substantially reduced the dexamethasone-induced expression of ALP. Studies on thermostability and sensitivity to various amino acid inhibitors indicated that the BC-M1 ALP is most similar to the placental form. Northern hybridization analysis also revealed that ALP mRNA transcripts in BC-M1 and term placenta are similar in size and are distinct from that of the placental-like mRNA transcript in choriocarcinoma cells. Analysis of the degradation of BC-M1 ALP mRNA showed a similar half-life of 27 h in the untreated and in dexamethasone- or RA-treated cells. These findings demonstrated that the induction of ALP in BC-M1 cells by dexamethasone is mainly due to the increase in the transcription of the ALP gene.
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PMID:Regulation of the expression of alkaline phosphatase in a human breast-cancer cell line. 794 40

Eighteen cases of intracranial germinoma (16 male and 2 female, age 2.5-30 years, average 16.7) were studied. Morphologically, the pathological changes in 18 cases were similar to those of testis seminoma or ovarian dysgerminoma. Among them, two were accompanied with choriocarcinoma and one with embryonal cancer. No cytoplasmic processes was detected by silver stain, but strongly positive to PAS-stain. All of the 18 cases in this series as well as another 8 cases of testis seminoma and ovarian dysgerminoma used as controls gave a positive reaction in alkaline phosphatase stain. Among the 18 cases of germinoma, except 3 out of 18 were CEA positive, otherwise, all were CEA, beta-HCG, SP1, AFP and GFAP negative. The syncytiotrophoblasts in the choriocarcinoma and embryonal cancer mentioned before were beta-HCG and SP1 positive, and additionally, the embryonal cancer also showed AFP positive. All these results support the hypothesis that both intracranial (extragonadal) and gonadal germinoma have a common cell origin.
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PMID:[Histopathological study of intracranial germinoma]. 840 4


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