Expression of NKX3.1 in normal and malignant tissues.
BACKGROUND
NKX3.1, a member of the NK-class of homeodomain proteins, is expressed primarily in the adult prostate and has growth suppression and differentiating effects in prostate epithelial cells.


METHODS
We performed immunohistochemical analysis for NKX3.1 and PSA expression in 4,061 samples included in a tissue microarray of a broad spectrum of human cancers and normal tissues.


RESULTS
NKX3.1 expression was seen in prostate epithelial cells, prostate cancer, normal testis, 9% of primary and 5% of metastatic infiltrating ductal breast carcinoma, and 27% of primary and 26% of metastatic infiltrating lobular breast carcinoma. In a cohort of 474 primary breast cancers with median follow-up over 62.5 month survival, we found no effect of NKX3.1 expression on prognosis. NKX3.1 expression was more restricted than the spectrum of prostate specific antigen expression.


CONCLUSIONS
Expression of NKX3.1 is highly restricted and is found primarily in benign and malignant prostatic epithelial cells and also in normal testis and lobular carcinoma of the breast.
Gelmann
Edward P
EP
Department of Oncology, Lombardi Cancer Center, Georgetown University School of Medicine, Washington, District of Columbia 20007-2197, USA. gelmanne@georgetown.edu
Bowen
Cai
C
Bubendorf
Lukas
L
D001943:Breast Neoplasms / Q000378:metabolism; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism; D018275:Carcinoma, Lobular / Q000378:metabolism; D004847:Epithelial Cells / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D018398:Homeodomain Proteins / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D009369:Neoplasms / Q000378:metabolism*; D011379:Prognosis; D011467:Prostate / Q000378:metabolism; D017430:Prostate-Specific Antigen / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000378:metabolism; D012016:Reference Values; D013737:Testis / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism*
D018398:Homeodomain Proteins; C491178:NKX3-1 protein, human; D014157:Transcription Factors; D017430:Prostate-Specific Antigen