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)

In this study, a somatic cell genetic approach was used to study the regulation of liver/bone/kidney alkaline phosphatase (ALPL) gene expression in osteoblasts. ALPL plays an important role in skeletal mineralization and serves as a good index of bone formation. A series of intertypic hybrids constructed by fusion of the human osteosarcoma TE-85 with the mouse fibrosarcoma La-t- demonstrated a 10-fold reduction of ALPL steady-state mRNA and enzyme activity, a phenomenon termed extinction. Hybrid subclones which reexpressed ALPL contained reduced numbers of fibroblast chromosomes compared to earlier passages. This suggests that a trans-acting negative regulatory factor expressed from the fibroblast genome regulates ALPL expression. Two factors known to influence ALPL expression are 1,25-dihydroxyvitamin D3 (1,25D3) and transforming growth factor-beta1 (TGFbeta1). 1,25D3 is involved in mobilizing bone calcium stores and TGFbeta1 plays a critical role in bone remodeling. The extinguished hybrids were exposed to 1,25D3, TGFbeta1, and a combination of these factors. For two hybrids, the combination induced reexpression of ALPL activity to levels comparable to the TE-85 parent, indicating a competition between the factors and the extinguisher(s). Neither factor alone could induce ALPL reexpression to the levels observed with the combination. In only one hybrid, the combination of factors synergistically increased ALPL expression. These data help define the cis sequence element(s) in the ALPL promoter which are involved in the negative regulation of this gene.
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PMID:1,25-Dihydroxyvitamin D3 and transforming growth factor-beta act synergistically to override extinction of liver/bone/kidney alkaline phosphatase in osteosarcoma hybrid cells. 868 72

Apart from defined histomorphologic features, increased Ki-67 indices and various numeric and structural chromosome aberrations, meningiomas of the intermediate (WHO grade II, atypical meningioma) and anaplastic type (WHO grade III) are cytogenetically distinguished from common-type meningiomas (WHO grade I) by frequent loss of the distal part of the short arm of one chromosome 1 (1p-), which formerly proved to be an independent predictor of shorter recurrence-free intervals. Histochemically, loss of alkaline phosphatase activity (ALPL, liver/bone/kidney type, EC 3.1.3.1) was another frequent, specific finding in meningiomas with signs of dedifferentiation. In a prospective study including 66 meningiomas, all common-type meningiomas except one case (18/19) were reactive for ALPL, whereas 75% (30/39) of intermediate type and all anaplastic meningiomas (8/8) showed loss of enzyme activity in large areas of the tumor. Exclusively, the ALPL negative phenotype was associated with 1p loss (15/19). Our data suggest that ALPL, which is coded as a single copy gene on chromosome 1p36.1-p34, is a useful marker enzyme for the loss of a putative regulatory (tumor suppressor) gene on chromosome 1p, or that ALPL itself represents a new tumor suppressor gene homozygously inactivated in meningiomas.
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PMID:Loss of alkaline phosphatase activity in meningiomas: a rapid histochemical technique indicating progression-associated deletion of a putative tumor suppressor gene on the distal part of the short arm of chromosome 1. 925 58

Meningiomas account for the most frequent primary intracranial neoplasms in adults. In 1993, the so-called atypical meningioma has additionally been introduced in the revised edition of the WHO Classification of Tumors of the Central Nervous System and should characterize meningiomas with an increased propensity to recur. Since the given qualitative histological criteria apply both to the "atypical" and anaplastic meningioma, mere histological grading appears somewhat critical. Therefore, additional parameters were tested for their contribution to meningioma grading: First of all, we succeeded in defining 3 meningioma "grades" by calculating corresponding 95% confidence intervals for the morphometrically assessed Ki-67 indices of 160 meningiomas in total, the validity of which was proved by comparison with the "recurrence"-free intervals. Histologically, atypical meningiomas were distinguished by a "syncytial", poorly structured growth pattern and macronucleoli. Only occasionally, nuclear pleomorphism, necroses and mitotic figures were found. Cytogenetics revealed, in 50% of the "atypical" and anaplastic meningiomas, partial loss of the short arm of one chromosome 1 (1p-). Histochemically, we could demonstrate, that the tissue non-specific type of alkaline phosphatase (ALPL), which is coded on chromosome 1p, is a convenient recurrence- and progression-associated marker enzyme for meningiomas with 1p-loss (loss of enzyme activity in 30/39 of intermediate and 8/8 anaplastic meningiomas). We favor to address the WHO "atypical" meningioma as meningioma of the intermediate type, since the attribute "atypical" in the context of histological diagnoses is highly susceptible to misinterpretations.
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PMID:[Meningioma. Classification and grading]. 943 70

GLIOMAS: As we demonstrated for supratentorial, diffuse gliomas in adults, a stratification into just two grades of malignancy, 'low' and 'high grade,' proved reliable and prognostically relevant. The discriminating histomorphological criterion for high-grade astrocytoma (WHO glioblastoma) as well as anaplastic oligodendroglioma and anaplastic oligoastrocytoma is endothelial hyperplasia/proliferation, which is usually associated with uptake of contrast medium in computed tomography and magnetic resonance imaging. As neoangiogenesis indicates glioma progression, it is worthwhile considering these radiographic features to judge the representativeness of the tumor samples critically. MENINGIOMAS: The revised edition of the WHO classification of brain tumors now includes the 'atypical' meningioma (WHO 'grade' II): Based on both its histomorphological features and prognosis, it should be placed between the common type and anaplastic meningioma. Nuclear area related Ki-67 proliferation indices, as determined by morphometry, were the prerequisite for outlining its histomorphological spectrum better. Cytogenetically, the most consistent progression-associated feature was loss of the distal part of the short arm of one chromosome 1 (1p-). Thus, a screening method using the tissue non-specific form of alkaline phosphatase (ALPL) as the respective marker enzyme was established. Diagnosing a meningioma of the intermediate type implies careful clinical and radiological patient follow-ups to detect tumor recurrences early.
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PMID:[Classification and grading of gliomas and meningiomas]. 986 48

Hypophosphatasia is a rare disease characterized by low serum levels of tissue non-specific alkaline phosphatase (TNSALP) and a spectrum of skeletal disease varying from the severest form with death in utero to mild with no clinical abnormality in adults. Currently, the diagnosis of hypophosphatasia is made on the basis of clinical findings, radiography, low serum alkaline phosphatase levels and raised abnormal phosphorylated metabolites; there are elevations in serum pyridoxal 5'-phosphate, urinary phosphoethanolamine and inorganic pyrophosphate. In borderline cases the biochemical diagnosis remains uncertain. Prenatally, diagnosis is made using radiography and ultrasonography together with chorionic villus tissue biopsy, in which TNSALP levels are measured using an antibody-based assay. Since hypophosphatasia results from mutations in the TNSALP gene we have, for the first time in two U.K. families, undertaken restriction fragment length polymorphism (RFLP) analysis using three intragenic RFLPs for BclI and MspI at the ALPL locus. One family was informative, and a mutant-allele-specific haplotype with respect to three RFLPs was defined. In the other family the disease was shown to segregate with one allele of the BclI RFLP, but the MspI RFLPs were not informative. The disease segregated in the two families with different alleles of the BclI RFLP, suggesting that the mutations are likely to be different. We confirm that DNA analysis is likely to be the way ahead for diagnosing hypophosphatasia, and that standardized screening methods need to be developed for detecting mutations in these and other families.
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PMID:Hypophosphatasia: diagnostic application of linked DNA markers in the dominantly inherited adult form. 1036 96

Hypophosphatasia is an inborn error of metabolism caused by a deficiency of liver-, bone- or kidney-type alkaline phosphatase due to mutations in the tissue-nonspecific alkaline phosphatase (ALPL) gene. Most of the 65 distinct mutations described to date are missense mutations, a result which must be correlated with the great variability of clinical expression ranging from stillbirth without mineralized bone to pathologic fractures developing only late in adulthood. Correlations of genotype and phenotype have been established on the basis of clinical data exhibited by the patients, transfection studies, computer-assisted modeling, and examination of biochemical properties of ALP in cultured fibroblasts of patients. Screening for mutations in the TNSALP gene allows genetic counseling and prenatal diagnosis of the disease in families with severe forms of hypophosphatasia, and screening may also be helpful in confirming diagnosis of hypophosphatasia when biochemical and clinical data are not clear. Screening is also the necessary first step in further studies to elucidate dominant transmission of the disease and of liver-, bone- and kidney-type alkaline phosphatase activity mechanism.
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PMID:Hypophosphatasia: the mutations in the tissue-nonspecific alkaline phosphatase gene. 1073 75

Meningioma is the most frequent tumor of neuroectodermal origin in humans. It is usually benign. Only a minority of cases shows progression to an anaplastic tumor (WHO grade II and III). Meningioma is generally a sporadic tumor. Multiple and familial cases are rare and mostly associated with (hereditary) neurofibromatosis 2 (NF2). Meningiomas show an unexpectedly high recurrence rate. Also, completely removed low-grade tumors can recur. Recurrence and multiplicity are correlated with the formation of a peritumoral edema. On the cytogenetic level, meningioma is the best-studied tumor in humans. Grade I tumors show either uniform monosomy 22 or a diploid karyotype. The majority of high-grade, but only a minority of low-grade, meningiomas show loss of merlin, a cytoskeleton-cytoplasm-linker protein. Merlin is the product of the NF2 gene located on chromosome 22. A second tumor suppressor gene on chromosome 22 has not yet been detected. In contrast to other solid tumors, progression of meningiomas is correlated with increasing hypodiploidy, showing characteristic clonal evolutions that mostly include chromosomes 14, 18, and 19 and, more rarely, 6 and 10. Structural aberrations are infrequent, except for the loss of the short arm of chromosome 1, which appears to be the decisive step for anaplastic growth. Comparative histochemical and molecular cytogenetic studies point to the alkaline phosphatase gene (ALPL, liver-bone-kidney type) located on 1p36.1-->p34 as a candidate tumor suppressor gene. A model is proposed that tries to explain - with a minimum number of essential steps - the origin, progression, infiltration, and recurrence of meningiomas.
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PMID:Meningioma: a cytogenetic model of a complex benign human tumor, including data on 394 karyotyped cases. 1152 14

Hypophosphatasia is an inherited disorder characterized by defective bone mineralization and deficiency of serum and tissue liver/bone/kidney alkaline phosphatase (L/B/K ALP) activity. We report the characterization of ALPL gene mutations in a series of 11 families from various origins affected by perinatal and infantile hypophosphatasia. Sixteen distinct mutations were found, fifteen of them not previously reported: M45V, G46R, 388-391delGTAA, 389delT, T131I, G145S, D172E, 662delG, G203A, R255L, 876-881delAGGGGA, 962delG, E294K, E435K, and A451T. This confirms that severe hypophosphatasia is due to a large spectrum of mutations in Caucasian populations.
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PMID:Severe hypophosphatasia: characterization of fifteen novel mutations in the ALPL gene. 1281 6

Hypophosphatasia is an inherited disorder due to mutations in the bone alkaline phosphatase (ALPL) gene. We report here a patient with childhood hypophosphatasia diagnosed at 1.4 yr because of pectus excavatum, large anterior fontanel, rachitic skeletal changes, and low serum alkaline phosphatase. Sequencing of the ALPL gene produced evidence of two distinct missense mutations, E174K (c.571G>A), of maternal origin, and a de novo mutation, M45I (c.186G>C). The study of various microsatellite polymorphisms ruled out false paternity and therefore confirmed that M45I occurred de novo in the paternal germline or in the early development of the patient. Site-directed mutagenesis showed that M45I results in the absence of in vitro alkaline phosphatase activity, suggesting that the mutation is a severe allele. In conclusion, childhood hypophosphatasia in this patient is the result of compound heterozygosity for the moderate mutation E174K and a novel severe de novo mutation M45I.
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PMID:Childhood hypophosphatasia due to a de novo missense mutation in the tissue-nonspecific alkaline phosphatase gene. 1567 Nov 2

Bovine embryonic stem (ES) cell lines reported to date vary in morphology and marker expression (e.g., alkaline phosphatase [ALPL], stage-specific embryonic antigen 4 [SSEA4], and OCT4) that normally are associated with the undifferentiated, pluripotent state. These observations suggest that the proper experimental conditions for consistently producing bovine ES cells have not been identified. Here, we report three bovine ES cell lines, one from in vitro-fertilized and two from nuclear transfer embryos. These bovine ES cells grew in large, multicellular colonies resembling the mouse ES and embryonic germ (EG) cells and human EG cells. Throughout the culture period, most of the cells within the colonies stained positive for ALPL and the cell surface markers SSEA4 and OCT4. The staining patterns of nuclear transfer ES cells were identical to those of the blastocysts generated in vitro yet different from most previously reported bovine ES cell lines, which were either negative or not detected. After undifferentiated culture for more than 1 yr, these cells maintained the ability to differentiate into embryoid bodies and derivatives of all three EG layers, thus demonstrating their pluripotency. However, unlike the mouse and human ES cells, following treatment with trypsin, type IV collagenase, or protease E, our bovine ES cells failed to self-renew and became spontaneously differentiated. Presumably, this resulted from an interruption of the self-renewal pathway. In summary, we generated pluripotent bovine ES cells with morphology similar to those of established ES cells in humans and mice as well as marker-staining patterns identical to those of the bovine blastocysts.
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PMID:Generation and characterization of pluripotent stem cells from cloned bovine embryos. 1574 21


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