Correlation of p27 protein expression with HER-2/neu expression in breast cancer.
Strong expression of human epidermal growth factor receptor 2 (HER-2)/neu in breast cancer has been associated with poor prognosis. Reduced expression of p27(Kip1), a cyclin-dependent kinase inhibitor, correlates with poor clinical outcome in breast cancer. In this study, we provide a correlation between these two important prognostic markers in patients with breast cancer. Breast tumor screening using immunohistochemistry indicated that downregulation of p27 correlated with HER-2/neu overexpression in studying 11 normal breast tissues and 51 primary breast carcinomas. We found HER-2/neu protein overexpression in 20 (41%) of 49 breast cancers and low p27 protein expression in 47 (92%) of 51 breast cancers. All 20 (100%) of the tumors that overexpressed HER-2/neu had low levels of p27 protein product; this correlation was statistically significant (P = 0.035). Decreasing p27 expression correlated with increasing HER-2/neu activity. Our results suggest that one function of the HER-2/neu product is to downregulate p27 expression in breast cancer. This study may be significant in selecting patients for HER-2/neu antibody therapy in the future. Mol. Carcinog. 30:169--175, 2001.
Newman
L
L
Department of Surgical Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA.
Xia
W
W
Yang
H Y
HY
Sahin
A
A
Bondy
M
M
Lukmanji
F
F
Hung
M C
MC
Lee
M H
MH
D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000378:metabolism*; D002277:Carcinoma / Q000378:metabolism; D002278:Carcinoma in Situ / Q000378:metabolism; D018797:Cell Cycle Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27; D004791:Enzyme Inhibitors / Q000378:metabolism; D005260:Female; D006801:Humans; D008869:Microtubule-Associated Proteins; D008875:Middle Aged; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D025521:Tumor Suppressor Proteins
D018797:Cell Cycle Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27; D004791:Enzyme Inhibitors; D008869:Microtubule-Associated Proteins; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D025521:Tumor Suppressor Proteins