Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:3.1.3.1 (alkaline phosphatase)
47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We analyzed the distribution of chromogranins A and B in normal and neoplastic endocrine tissues with secretory granules using 35S-labeled and biotin-labeled oligonucleotide probes by in situ hybridization (ISH). Both radioactive and nonradioactive probes detected messenger RNAs (mRNAs) in frozen and paraffin tissue sections. Endocrine tissues with variable immunoreactivities for chromogranin A protein, such as small-cell lung carcinomas, neuroblastomas, insulinomas, and parathyroid adenomas, expressed the mRNA for chromogranins A and B in most cells. Some technical problems with the biotinylated probes included nonspecific nuclear staining and endogenous alkaline phosphatase, which was not completely abolished by levamisole pretreatment. A differential distribution of chromogranins A and B was seen in pituitary prolactinomas, which expressed abundant chromogranin B but not chromogranin A mRNAs, and in parathyroid adenomas, which expressed abundant chromogranin A but only small amounts of chromogranin B mRNAs. These results indicate that ISH can be used to detect chromogranins A and B in endocrine tissues with radioactive and biotinylated oligonucleotide probes and that the mRNAs for chromogranin A and B are demonstrable in some tumors even when the chromogranin proteins cannot be detected by immunohistochemistry.
...
PMID:Detection of chromogranins A and B in endocrine tissues with radioactive and biotinylated oligonucleotide probes. 229 79

The immunoprofiles of 121 germ cell and trophoblastic neoplasms were defined, using a battery of antibodies against cytokeratin (CK), vimentin (VIM), epithelial membrane antigen (EMA), placental alkaline phosphatase (PLAP), S-100 protein, leukocyte common antigen (LCA), UCHL-1, LN-2, carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), chromogranin A, Leu-7, alpha-fetoprotein (AFP), alpha-1-antitrypsin (AAT), and the beta subunit of human chorionic gonadotropin (BHCG). In addition to 85 neoplasms of testicular origin, the cases included eight ovarian germ cell tumors and 28 extragonadal neoplasms. All tissues had been subjected to formalin fixation and paraffin embedding. Similar immunoreactivity patterns were seen in gonadal and extragonadal neoplasms, gestational and nongestational choriocarcinomas, components of mixed germ cell tumors and their pure counterparts, and metastatic and primary lesions. Placental alkaline phosphatase was a sensitive marker of germ cell differentiation, and expression of this marker in the absence of EMA appeared to be a staining pattern unique to germ cell tumors. Both LCA and S100 were absent in neoplastic germ cells, and thus were useful in differentiating these tumors from malignant lymphoma and malignant melanoma, respectively. Cytokeratin was helpful in distinguishing seminomas/dysgerminomas from nonseminomatous germ cell tumors, although 10% of seminomas showed focal or diffuse cytokeratin reactivity. Finally, 75% of all germ cell neoplasms displayed NSE, calling the specificity of this determinant into question.
...
PMID:Immunohistochemistry of germ cell and trophoblastic neoplasms. 245 24

Chromogranin A is a secretory protein expressed widely in neuroendocrine cells. It is known to be phosphorylated but the precise sites of phosphorylation are not known. We have isolated, from bovine pancreas and ileum, chromogranin A fragments corresponding to a region giving rise to a biologically active product, pancreastatin. Phosphorylation patterns were determined by fast atom bombardment mass spectrometry and alkaline phosphatase digestion followed by ion-exchange chromatography and radioimmunoassay. In the pancreas, there were unmodified, mono- and di-phosphorylated forms of the fragment chromogranin A(248-313) with Arg and Glu at positions 293 and 301 respectively; in addition, there were small amounts of monophosphorylated peptide with an alternative primary sequence of His and Lys at 293 and 301 respectively. Two products of cleavage, pancreastatin and the fragment 297-313, were also found in unmodified and monophosphorylated forms. In the ileum, peptides with both alternative primary sequences were found, pancreastatin was absent, and phosphorylation was generally less than in the pancreas. Chromogranin A-derived peptides therefore exhibit tissue-specific patterns of phosphorylation and cleavage, and at least two phosphorylation sites occur in the region giving rise to a biologically active product.
...
PMID:Post-translational processing of chromogranin A: differential distribution of phosphorylated variants of pancreastatin and fragments 248-313 and 297-313 in bovine pancreas and ileum. 824 Feb 72

Serum levels of parathyroid hormone (PTH), alkaline phosphatase (ALP), calcium, creatinine, and vitamin D and the glomerular filtration rate were compared with the histologic properties and expression of PTH and chromogranin A in excised parathyroid adenomas from patients with primary hyperparathyroidism (pHPT). PTH and chromogranin A were detected immunohistochemically, and their mRNA was demonstrated by in situ hybridization with quantification of their mRNA levels by image analysis. There was a positive correlation between the cellular levels of PTH mRNA and the cellular levels of chromogranin A mRNA (r = 4.4; p < 0.05). However, within certain parts of the adenomas, mostly consisting of chief cells, the expression of PTH mRNA and chromogranin A mRNA was heterogeneous and the levels did not correspond to each other. A reduced suppressibility of PTH in patients with pHPT was confirmed. Although cellular levels of PTH and chromogranin A and their mRNAs were low in the oxyphilic parts of the adenomas, there was no correlation between the amount of oxyphilic cells in the adenomas and the suppressibility of PTH by calcium. There was also no association between the cellular levels of PTH mRNA or chromogranin A mRNA as studied by image analysis and "calcium sensitivity." Our results thus demonstrate that although PTH and chromogranin A mRNA levels are in general correlated to each other there are differences in their expression within and between individual parathyroid adenomas. It therefore seems likely that the expression of PTH and chromogranin A are differentially regulated, and that PTH and chromogranin A may not always be co-secreted. This point could be of importance, as chromogranin A and its cleavage products are known to influence PTH secretion.
...
PMID:Parathyroid function and histology in patients with parathyroid adenoma: correlation of clinical and morphologic findings. 920 47

In situ DNA fragmentation assays have proved to be particularly useful in the detection of apoptosis in routinely processed, paraffin-embedded tissue sections. In the present study, a triple-antigen labelling technique was performed to demonstrate DNA fragmentation (apoptosis), cell proliferation (MIB-1), and phenotypic markers in the same tissue section. The in situ apoptosis assay was conducted with the TUNEL method developed by a avidin-biotin alkaline phosphatase complex (ABcomplex/AP). The proliferation-associated MIB-1 antigen was demonstrated in the second staining sequence by the avidin-biotin peroxidase method (ABC). The phenotypic markers chromogranin A or prostate-specific antigen (PSA) were visualized by the alkaline phosphatase anti-alkaline phosphatase method (APAAP) in the third staining sequence. The feasibility of this triple-labelling technique was tested in formalin-fixed, paraffin-embedded tissue of prostatic adenocarcinomas from 8 patients with recurrent, hormone-refractory disease. Although these tumours revealed marked neuroendocrine differentiation, cell proliferation and apoptosis were detected exclusively in non-endocrine (chromogranin A-negative) tumour cells that expressed PSA variably. The triple-labelling protocol described here allows the phenotypic characterization of proliferating and apoptotic cell populations in the same tissue section. It may be useful in studies of tissue kinetics in physiological and pathological processes.
...
PMID:Simultaneous detection of DNA fragmentation (apoptosis), cell proliferation (MIB-1), and phenotype markers in routinely processed tissue sections. 1007 Dec 38

Bovine chromogranin A (CgA), together with secreted alkaline phosphatase (SEAP) as an external control for apical secretion were expressed in MDCK cells to test if CgA contains sorting signals for polarized secretion. CgA, SEAP, and the endogenous apical marker GP80 were secreted 75-80% apically. Basolateral secretion of SEAP was inhibited 40% by ammonium chloride. Sulfate labeling and digestion with chondroitinase ABC revealed a 120 kDa proteoglycan-CgA and 75 kDa CgA. Inhibition of proteoglycan synthesis did not affect apical secretion of CgA. As CgA is not N-glycosylated, we used tunicamycin to test if cellular N-glycosylation is required for apical sorting. Tunicamycin reversed the polarity of secretion of CgA to the basolateral side. These results suggest that CgA contains dominant apical and recessive basolateral sorting information.
...
PMID:Polarized secretion of the regulated secretory protein chromogranin A. 1075 75

Calcium-induced aggregation has been proposed to play a role in the sorting and storage of secretory proteins in secretory granules of endocrine cells. The regulation of this process is not known. Hexahistidine epitope tags were used to create aggregation chaperones that enhance the calcium-induced aggregation of secretory granule proteins in vitro. Indeed, 100% recovery of the aggregating target protein was achieved without any modification of the target protein. The aggregation chaperone is not trapped in the aggregates. Co-expression of His(6)-tagged secreted alkaline phosphatase and the regulated secretory protein chromogranin A resulted in an increased chromogranin storage in secretory granules, and stimulated secretion of chromogranin A increased 50%. However, secretion of secreted alkaline phosphatase was not affected by the hexahistidine epitope tag. Thus, calcium-induced aggregation is not a passive process; rather, aggregation and sorting of secretory proteins can be regulated by aggregation chaperones in the secretory pathway of endocrine cells.
...
PMID:Aggregation chaperones enhance aggregation and storage of secretory proteins in endocrine cells. 1086 58

Aggregation chaperones, consisting of secretory proteins that contain a hexa-histidine epitope tag, enhance the calcium-induced aggregation of regulated secretory proteins and their sorting to secretory granules. The goal of this study was to gain a better understanding of this unusual aggregation mechanism. Hexa-histidine-epitope-tagged secreted alkaline phosphatase, an aggregation chaperone, enhanced the in vitro aggregation of chromogranin A in the presence of calcium, but not in the presence of magnesium or other divalent cations. As an exception, chromogranin was completely aggregated by zinc, even in the absence of the aggregation chaperone. In addition, fluorescence spectroscopy of the aggregation reaction mixture showed an increase in fluorescence intensity consistent with the formation of protein aggregates. The calcium-induced aggregation of chromogranin A was completely inhibited by 0.2% Triton X-100, suggesting that it involves hydrophobic interactions. In contrast, the detergent did not affect chaperone-enhanced aggregation, suggesting that this aggregation does not depend on hydrophobic interactions. EDTA-treated chaperone did not enhance chromogranin A aggregation, indicating that divalent cations are necessary for chaperone action. Although the structure of the aggregation chaperone was not important, the size of the chaperone was. Thus the free His-hexapeptide could not substitute for the aggregation chaperone. Based on these results, we propose that the hexa-histidine tag, in the context of a polypeptide, acts as a divalent cation-dependent nucleation site for chromogranin A aggregation.
...
PMID:In vitro aggregation of the regulated secretory protein chromogranin A. 1217 32

Regulated secretory proteins are stored in secretory granules. While the sorting and storage process appears similar in endocrine and exocrine cells, the extent of overlap of sorting between endocrine and exocrine cell types is not clear. It is predicted that exocrine regulated secretory proteins that are stored with high efficiency in exocrine granules would also be stored efficiently in endocrine granules. To test this hypothesis, parotid secretory protein (PSP), which is stored efficiently in parotid acinar cells, was expressed in the endocrine cell lines GH4C1 and PC12. PSP undergoes stimulated secretion in both cell types. Secretion is similar to that of the endocrine regulated secretory protein chromogranin A but distinct from secreted alkaline phosphatase, a marker for the constitutive secretory pathway in endocrine cells. Subcellular fractionation of GH4C1 cells revealed that PSP co-fractionates with chromogranin A but not with secreted alkaline phosphatase.
...
PMID:Sorting of an exocrine secretory protein to the regulated secretory pathway in endocrine cells. 1243 94

This retrospective study aimed at determining the prognostic significance of neuroendocrine markers chromogranin A (CgA), pro-gastrin releasing peptide (ProGRP) and neuron-specific enolase (NSE), together with the cytokeratin 19 marker CYFRA 21-1 in small cell lung cancer (SCLC). A total of 148 histologically proven and previously untreated SCLC patients were included. Among them 118 patients received a cisplatin-etoposide combination or cisplatin-etoposide-cyclophosphamide-4'-epidoxorubicin combination. All tumour markers were tested using immunoradiometric assays except for ProGRP which was tested using an enzyme-linked immunosorbent assay. The thresholds for marker serum titrations were 53 pg/ml, 65, 17, and 3.6 ng/ml for ProGRP, CgA, NSE and CYFRA 21-1 respectively. Univariate analysis showed that patients affected by one of the following characteristics proved to have a significant shorter survival in comparison with the opposite status of each variable: age over 63 years, extensive-stage, serum LDH level higher than 600 U/l, serum NSE level higher than 17 ng/ml, serum CgA level higher than 65 ng/ml and serum CYFRA 21-1 level higher than 3.6 ng/ml. In addition, there was a trend towards a statistical significance for a high serum alkaline phosphatase level and a performance status equal to or worse than two. The following variables were independent determinants of a poor outcome: a poor performance status (hazard ratio [95% confidence interval]: 1.51 [1.02-2.22]), a high CgA level (HR: 1.61 [1.06-2.45]), a high CYFRA 21-1 level (HR: 2.10 [1.40-3.14]) and an age older than 63 years (HR: 1.68 [1.14-2.48]). When the multivariate analysis was restricted to patients receiving a cisplatin-etoposide-based chemotherapy, the same variables were prognostic determinants with nearly similar hazard ratios. In conclusion, aside classical variables such as age and performance status, high serum CYFRA 21-1 and high serum CgA level in SCLC are both prognostic determinants of prognosis, in particular in patients receiving conventional chemotherapy consisting of cisplatin and etoposide-based combinations.
...
PMID:Neuroendocrine and cytokeratin serum markers as prognostic determinants of small cell lung cancer. 1258 64


1 2 Next >>

---