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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
2
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pubmed:dateCreated |
1996-6-7
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pubmed:abstractText |
The precise regulation and maintenance of balance between cell proliferation and cell death in multicellular organisms is critical for tissue homeostasis. bcl-2 initiates a new gene family involved in the regulation of cell death and survival without affecting cell proliferation. Expression of Bcl-2 has been reported in a wide range of hematopoietic cells, nonneoplastic epithelia (both hormone-responsive and nonresponsive), and epithelial malignancies. Although the major group of epithelial cells expressing Bcl-2 protein are in the proliferating zones, expression is not directly related to cell proliferation. Bcl-2 is also associated with stem cells committed to differentiation and morphogenesis. The survival advantage provided by Bcl-2 prolongs the life span of epithelial cells with differentiation potential and allows proliferation, differentiation, and morphogenesis to proceed. The gene expression in hormone-responsive organs may contribute to the sustained life of those terminally differentiated epithelial cells and a decrease in Bcl-2 levels leads to cell death by apoptosis. Overexpression of bcl-2 protects epithelial cells from death, but it is neither able to immortalize normal cells, nor to cause tumorigenic transformation of immortalized epithelial cells. Heterogeneous expression of Bcl-2 in epithelial malignancies suggests that the gene is differentially regulated. Furthermore, its expression in association with precancerous lesions suggests a role in the early stage of tumorigenesis. The effects of Bcl-2 expression on sensitivity of epithelial cells to drug, radiation, and hormone therapies vary depending on the typed of tumor. Expression of Bcl-2 is associated with resistance to hormone therapy and recurrence in prostate carcinomas, whereas in lung and breast carcinomas it is associated with a better prognosis. Studies now being performed should clarify the underlying mechanisms of differential gene regulation in different tissues and show the clinical significance of the expression of bcl-2 and other members of the bcl-2 gene family.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:month |
Feb
|
pubmed:issn |
0046-8177
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pubmed:author | |
pubmed:issnType |
Print
|
pubmed:volume |
27
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
102-10
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:8617450-Animals,
pubmed-meshheading:8617450-Apoptosis,
pubmed-meshheading:8617450-Cell Differentiation,
pubmed-meshheading:8617450-Cell Transformation, Neoplastic,
pubmed-meshheading:8617450-Epithelium,
pubmed-meshheading:8617450-Gene Expression,
pubmed-meshheading:8617450-Gene Expression Regulation, Developmental,
pubmed-meshheading:8617450-Gene Expression Regulation, Neoplastic,
pubmed-meshheading:8617450-Humans,
pubmed-meshheading:8617450-Morphogenesis,
pubmed-meshheading:8617450-Neoplasms,
pubmed-meshheading:8617450-Proto-Oncogene Proteins,
pubmed-meshheading:8617450-Proto-Oncogene Proteins c-bcl-2
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pubmed:year |
1996
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pubmed:articleTitle |
bcl-2: role in epithelial differentiation and oncogenesis.
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pubmed:affiliation |
Department of Histopathology and Surgery, Royal Postgraduate Medical School/Hammersmith Hospital, London, UK.
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pubmed:publicationType |
Journal Article,
Review,
Research Support, Non-U.S. Gov't
|