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

Human osteosarcoma specimens were sliced in a cryomicrotome under strict morphological guidance. Serial sections of ten 10 micron slices each were collected in two groups according to morphologic criteria, one containing mostly undifferentiated tumor tissue, the other predominantly well-differentiated tumor tissue. The two series were analysed chemically for alkaline phosphatase (APase) acid phosphatase (acPase), beta-glucuronidase and proteolytic activities; protein, phosphorus, hydroxyproline, hexosamine, water and collagen contents were also determined. Four different types of osteosarcoma were studied: case 1 was a highly malignant osteoblastic osteosarcoma, case 2 a small cell sclerosing osteosarcoma case 3 a well-differentiated osteosarcoma, and case 4 a highly malignant anaplastic osteosarcoma. The types of cases 1, 2 and 3 are known as osteoid-forming tumors. In their less well differentiated areas APase activity was about twice as high as in better differentiated osteosarcoma. In contrast, no APase was found in the wholly undifferentiated areas of case 4, while the enzyme showed a marked increase in the areas of incipient differentiation of this tumor. The matrix of tumors differs with regard to collagen and hexosamine contents, in accordance with the general state of differentiation. In general, increasing hexosamine contents together with decreasing hydroxyproline contents will reflect the anaplastic, dedifferentiated osteosarcoma. Calcification evident in the better differentiated areas of osteosarcoma is indicated by the phosphorus content, highest in case 2, with cases 3, 1, and 4 following in sequential order.
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PMID:Biological characterization of human bone tumors. V. Zonal characterization of osteosarcoma: topological biochemical analysis correlated with morphology. 390 6

The current definition of osteosarcoma, based on the prescence of tumor osteoid, is unsatisfactory because it fails to identify some examples of chondroblastic, fibroblastic, and anaplastic osteosarcoma having no demonstrable tumor osteoid. The tumor cells in osteosarcoma, whether osteoblastic, chondroblastic, fibroblastic, or anaplastic, contain abundant alkaline phsophatase, whereas this enzyme is scanty or absent in condrosarcoma and fibrosarcoma. It is therefore proposed that these bone sarcomas are best defined according to the origin of the constituent tumor cells and their alkaline phosphatase content: osteosarcoma--a malignant tumor of osteoblasts (alkaline phosphatase positive); chondrosarcoma--a malignant tumor of chondroblasts (alkaline phosphatase negative); and fibrosarcoma--a malignant tumor of fibroblasts (alkaline phosphatase negative).
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PMID:Definitions of osteosarcoma, chondrosarcoma, and fibrosarcoma of bone. 693 Mar 19