B7-H4 overexpression in ovarian tumors.
OBJECTIVE
Despite great advances in therapeutic management, the mortality rate for ovarian cancer has remained relatively stable over the past 50 years. This study was designed to evaluate the expression of B7-H4 protein, recently identified as a potential molecular marker of breast and ovarian cancer by quantitative PCR analysis, in benign tumors, tumors of low malignant potential and malignant tumors of the ovary.


METHODS
Archival formalin-fixed tissue blocks from serous, mucinous, endometrioid and clear cell ovarian tumors were evaluated by immunohistochemistry for the distribution of B7-H4 expression, and staining intensity was measured by automated image analysis. Univariate analyses were used to test for statistically significant relationships.


RESULTS
B7-H4 cytoplasmic and membranous expression was detected in all primary serous (n = 32), endometrioid (n = 12), and clear cell carcinomas (n = 15), and in all metastatic serous (n = 23) and endometrioid (n = 7) ovarian carcinomas. By contrast, focal B7-H4 expression was detected in only 1/11 mucinous carcinomas. The proportion of positive cells and median staining intensity was greater in serous carcinomas than in serous cystadenomas or serous tumors of low malignant potential, and the differences were statistically significant (P < 0.0001 and P = 0.034, respectively). The median staining intensity was also significantly greater in endometrioid carcinomas than in endometriosis (P = 0.005).


CONCLUSIONS
The consistent overexpression of B7-H4 in serous, endometrioid and clear cell ovarian carcinomas and the relative absence of expression in most normal somatic tissues indicates that B7-H4 should be further investigated as a potential diagnostic marker or therapeutic target for ovarian cancer.
Tringler
Barbara
B
Department of Pathology, University of Colorado Health Sciences Center, B-216, 4200 East Ninth Avenue, Denver, CO 80262, USA.
Liu
Wenhui
W
Corral
Laura
L
Torkko
Kathleen C
KC
Enomoto
Takayuki
T
Davidson
Susan
S
Lucia
M Scott
MS
Heinz
David E
DE
Papkoff
Jackie
J
Shroyer
Kenneth R
KR
D018262:Adenocarcinoma, Clear Cell / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D002288:Adenocarcinoma, Mucinous / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018122:B7-1 Antigen / Q000096:biosynthesis* / Q000276:immunology; D014408:Biomarkers, Tumor / Q000096:biosynthesis* / Q000276:immunology; D015153:Blotting, Western; D018269:Carcinoma, Endometrioid / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D018284:Cystadenocarcinoma, Serous / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D010051:Ovarian Neoplasms / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D060907:V-Set Domain-Containing T-Cell Activation Inhibitor 1
D018122:B7-1 Antigen; D014408:Biomarkers, Tumor; D060907:V-Set Domain-Containing T-Cell Activation Inhibitor 1; C475826:VTCN1 protein, human