Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2000-8-22
pubmed:abstractText
Epidemiological data suggest that oestrogen contributes to the aetiology of colonic cancer. Furthermore, recent studies have suggested that local hormone metabolism may play a key role in determining colonic responsiveness to oestrogen. To further clarify this mechanism we have characterized the expression and regulation of isozymes of 17beta-hydroxysteroid dehydrogenase (17beta-HSD) in vitro and in situ. Immunohistochemistry was used to confirm expression of the type 2 and 4 isozymes of 17beta-HSD (17beta-HSD2 and 4) in normal colonic epithelial cells. Parallel studies suggested that both isozymes were abnormally expressed in colonic tumours and this was confirmed by Western blot analyses. Abnormal expression of 17beta-HSD2 and 4 proteins was also observed in Caco-2, HT-29 and SW620 colonic cancer cell lines, although the overall pattern of oestrogen metabolism in these cells was similar to that seen in primary colonic mucosal tissue. The predominant activity (conversion of oestradiol to oestrone) was highest in Caco-2>SW620>HT-29, which correlated inversely with the rate of proliferation of the cell lines. Regulatory studies using SW620 cells indicated that the most potent stimulator of oestradiol to oestrone inactivation was the antiproliferative agent 1,25-dihydroxyvitamin D3 (1,25D3), whilst oestradiol itself inhibited 17beta-HSD activity. Both oestradiol and 1,25D3 decreased mRNA for 17beta-HSD2 and 4. Data indicate that the high capacity for inactivation of oestrogens in the colon is associated with the presence of 17beta-HSD2 and 4 in epithelial cells. Abnormal expression of both isozymes in colonic cancer cells and the stimulation of oestrogen inactivation by the antiproliferative agent 1,25D3 highlights a possible role for 17beta-HSD isozymes as modulators of colonic cell proliferation.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-10068081, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-10089907, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-10372714, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-10385431, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-10418994, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-10634418, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-1325275, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-1892541, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-3126957, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-3678749, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-6020135, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-6122963, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-7616598, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-7707438, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-7859926, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-8074447, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-8240985, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-8608963, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-8636351, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-8707404, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-8813150, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-8923858, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-8943783, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-9038620, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-9275056, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-9602706, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-9625169, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-9712896, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-9771468, http://linkedlifedata.com/resource/pubmed/commentcorrection/10945506-9949685
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0007-0920
pubmed:author
pubmed:issnType
Print
pubmed:volume
83
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
550-8
pubmed:dateRevised
2010-9-14
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Oestrogen inactivation in the colon: analysis of the expression and regulation of 17beta-hydroxysteroid dehydrogenase isozymes in normal colon and colonic cancer.
pubmed:affiliation
Division of Medical Sciences, The Queen Elizabeth Hospital, The University of Birmingham, UK.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't