Distribution of Hsp-27 and HER-2/neu in in situ and invasive ductal breast carcinomas.
BACKGROUND
The overexpression of heat shock protein 27 (hsp-27) in early-stage breast cancer is associated with histopathologic features of poor prognosis and clinically with an increased probability of disease recurrence. Hsp-27 is overexpressed in 25% of invasive ductal carcinomas (IDC); however, its distribution in ductal carcinoma in situ (DCIS) and DCIS associated with IDC has not been investigated. We postulated that hsp-27 might be detected and variably expressed in DCIS and, like HER-2/neu oncoprotein expression, might be a tumor-specific marker worthy of future clinical investigation.


METHODS
To test these hypotheses, the distribution of hsp-27 in noncomedo and comedo DCIS, and DCIS associated with IDC, was evaluated by immunohistochemistry and compared with HER-2/neu expression within the same cancers.


RESULTS
Hsp-27 was overexpressed in 28 of 47 (approximately 60%) cases of DCIS; expression in pure DCIS was 16 of 24 (67%), and 12 of 23 (approximately 50%) in DCIS associated with IDC. Hsp-27 expression by in situ and invasive components of the same neoplasm were concordant in 22 of 23 (approximately 95%) cases tested. Comedo variants appeared to have somewhat higher hsp-27 expression than noncomedo DCIS, whether or not there was an associated IDC. These results are reminiscent of HER-2/neu oncoprotein expression in DCIS and DCIS associated with IDC observed by others. However, although 4 of 22 (18%) cancers containing DCIS + IDC expressed HER-2/neu, no relationship with hsp-27 expression in the same cancers was observed.


CONCLUSIONS
We found a high incidence of hsp-27 overexpression in DCIS and in DCIS associated with IDC. This rate is twice that previously observed in IDC alone. Hsp-27 expression is independent of HER-2/neu expression.
Storm
F K
FK
Department of Surgery, University of Wisconsin School of Medicine, Madison.
Gilchrist
K W
KW
Warner
T F
TF
Mahvi
D M
DM
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism*; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism*; D002278:Carcinoma in Situ / Q000235:genetics / Q000378:metabolism*; D018270:Carcinoma, Ductal, Breast / Q000235:genetics / Q000378:metabolism*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D013194:Staining and Labeling
D014408:Biomarkers, Tumor; D006360:Heat-Shock Proteins; D018719:Erb-b2 Receptor Tyrosine Kinases