Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
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Target Concepts:
Gene/Protein
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Enzyme
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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)
It has been reported that two inducible prostaglandin synthetic enzymes, cylooxygenase-2 (COX-2) and microsomal PGE synthase, are over-expressed in non-small cell lung cancer (NSCLC). Using quantitative reverse transcription-polymerase chain reaction, we analyzed RNA levels of the key prostaglandin catabolic enzyme, NAD+-linked 15-hydroxyprostaglandin dehydrogenase (15-PGDH), in 19 pairs of NSCLC tumors and adjacent non-malignant tissue from the same patient. We found that 100% of tumor-tissue pairs showed at least a 2-fold decrease and 61% showed a 10-fold decrease. This suggests that the increased expression of COX-2 and PGE synthase in tumors may work in concert with the decreased expression of 15-PGDH to amplify an increase in tissue levels of proliferative PGE2. To further explore if 15-PGDH is related to tumorigenesis, athymic nude mice were injected with control A549 cells or cells transiently over-expressing wild-type or mutant 15-PGDH (Y151F). It was found that mice injected with control A549 cells or with cells expressing mutant enzyme produced tumors normally. However, mice injected with A549 cells expressing wild-type 15-PGDH had a significant decrease in tumor growth. Examining the effects of 15-PGDH expression on cellular changes in A549 cells, we found that over-expression of 15-PGDH induced apoptosis of A549 cells as evidenced by fragmentation of DNA, activation of pro-caspase 3, cleavage of
poly(ADP-ribose) polymerase
and decreased expression of Bcl-2. We also found that the expression of 15-PGDH was negatively related to that of pro-adhesive and invasive CD44. Furthermore, the expression of 15-PGDH was found to be stimulated by
hyaluronidase
. These results suggest that 15-PGDH may decrease the level of proliferative PGE2, induce apoptosis and function like a tumor suppressor.
...
PMID:NAD+-linked 15-hydroxyprostaglandin dehydrogenase (15-PGDH) behaves as a tumor suppressor in lung cancer. 1535 36
Tumor cells express HYAL1
hyaluronidase
, which degrades hyaluronic acid. HYAL1 expression in bladder cancer cells promotes tumor growth, invasion, and angiogenesis. We previously described five alternatively spliced variants of HYAL1 that encode enzymatically inactive proteins. The HYAL1-v1 variant lacks a 30-amino acid sequence that is present in HYAL1. In this study, we examined whether HYAL1-v1 expression affects bladder cancer growth and invasion by stably transfecting HT1376 bladder cancer cells with a HYAL1-v1 cDNA construct. Although HYAL1-v1 transfectants expressed equivalent levels of enzymatically active HYAL1 protein when compared with vector transfectants, their conditioned medium had 4-fold less
hyaluronidase
activity due to a noncovalent complex formed between HYAL1 and HYAL1-v1 proteins. HYAL1-v1 transfectants grew 3- to 4-fold slower due to cell cycle arrest in the G(2)-M phase and increased apoptosis. In HYAL1-v1 transfectants, cyclin B1, cdc2/p34, and cdc25c levels were > or =2-fold lower than those in vector transfectants. The increased apoptosis in HYAL1-v1 transfectants was due to the extrinsic pathway involving Fas and Fas-associated death domain up-regulation, caspase-8 activation, and BID cleavage, leading to caspase-9 and caspase-3 activation and
poly(ADP-ribose) polymerase
cleavage. When implanted in athymic mice, HYAL1-v1-expressing tumors grew 3- to 4-fold slower and tumor weights at day 35 were 3- to 6-fold less than the vector tumors (P < 0.001). Whereas vector tumors were infiltrating and had high mitoses and microvessel density, HYAL1-v1 tumors were necrotic, infiltrated with neutrophils, and showed low mitoses and microvessel density. Therefore, HYAL-v1 expression may negatively regulate bladder tumor growth, infiltration, and angiogenesis.
...
PMID:HYAL1-v1, an alternatively spliced variant of HYAL1 hyaluronidase: a negative regulator of bladder cancer. 1714 67