Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.36 (hyaluronidase)
 4,606 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The activity of bull sperm hyaluronidase (hyaluronate 3-glycanohydrolase, EC 3.2.1.36) is increased by the inclusion of polycations in the assay mixture. At pH 3.8, bovine serum albumin and histone give the greatest stimulation, while protamine sulfate, spermine, spermidine and hyamine 2389 stimulate to a lesser extent. Enzyme activity increases with serum albumin concentration to a nearly constant, high level at serum albumin concentrations greater than 1 mg/ml. Other stimulatory compounds show a similar concentration dependence except that inhibition of enzyme activity occurs at high concentrations of stimulator. The degree of stimulation depends on the pH, sample concentration and substrate concentration. Enzyme preparations with a low protein content give the greatest stimulation, while preparations with a high protein content show little stimulation. The concentration of serum albumin required for maximum stimulation increases with increased hyaluronic acid concentration. The results suggest that the stimulation of sperm hyaluronidase is nonspecific and results from an interaction of the polycation with hyaluronic acid. Since protein in the enzyme preparation substitutes for exogenous stimulator to a varying degree, serum albumin should be included in the assay mixture for sperm and testicular hyaluronidase to assure measurement of maximum enzyme activity.
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PMID:Stimulation of bull sperm hyaluronidase by polycations. 4 Jun 4

The foregoing discussion indicates that hyaluronidases probably play an important part in the control of development. In morphogenesis, they may be involved in epithelial-mesenchymal inductive interactions, in non-malignant invasion when one tissue displaces another in normal development, in controlling cell movements, in modulating changes of shape of cells and sheets of cells, in controlling the permeability of tissues and regulating the ionic environment within the embryo. There is also evidence indicating that hyaluronidases are involved in the initiation of cytodifferentiation pathways, perhaps via direct or indirect effects upon the cell division cycle and histone-DNA interactions. The evidence presented indicates that hyaluronidases are important repeatedly at different stages of embryonic development and differentiation, where periods of high activity follow others of reduced activity in localized regions of the embryo. Some new results were also presented, showing the presence of different hyaluronidase activities at early stages of chick embryo development. The highest levels of hyaluronidase activity were found in the primitive streak and mesoderm.
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PMID:Mini-review: hyaluronidases in early embryonic development. 638 51

Hyaluronic acid and HYAL1-type hyaluronidase show high accuracy in detecting bladder cancer and evaluating its grade, respectively. Hyaluronic acid promotes tumor progression; however, the functions of hyaluronidase in cancer are largely unknown. In this study, we stably transfected HT1376 bladder cancer cells with HYAL1-sense (HYAL1-S), HYAL1-antisense (HYAL1-AS), or vector cDNA constructs. Whereas HYAL1-S transfectants produced 3-fold more HYAL1 than vector transfectants, HYAL1-AS transfectants showed approximately 90% reduction in HYAL1 production. HYAL1-AS transfectants grew four times slower than vector and HYAL1-S transfectants and were blocked in the G2-M phase of the cell cycle. The expression of cdc25c and cyclin B1 and cdc2/p34-associated H1 histone kinase activity also decreased in HYAL1-AS transfectants. HYAL1-S transfectants were 30% to 44% more invasive, and HYAL1-AS transfectants were approximately 50% less invasive than the vector transfectants in vitro. In xenografts, there was a 4- to 5-fold delay in the generation of palpable HYAL1-AS tumors, and the weight of HYAL1-AS tumors was 9- to 17-fold less than vector and HYAL1-S tumors, respectively (P < 0.001). Whereas HYAL1-S and vector tumors infiltrated skeletal muscle and blood vessels, HYAL1-AS tumors resembled benign neoplasia. HYAL1-S and vector tumors expressed significantly higher amounts of HYAL1 (in tumor cells) and hyaluronic acid (in tumor-associated stroma) than HYAL1-AS tumors. Microvessel density in HYAL1-S tumors was 3.8- and 9.5-fold higher than that in vector and HYAL1-AS tumors, respectively. These results show that HYAL1 expression in bladder cancer cells regulates tumor growth and progression and therefore serves as a marker for high-grade bladder cancer.
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PMID:HYAL1 hyaluronidase: a molecular determinant of bladder tumor growth and invasion. 1578 37