B7-h3 ligand expression by primary breast cancer and associated with regional nodal metastasis.
OBJECTIVE
: B7 ligand family members have been shown to be important immunoregulatory factors in host tumor immune responses. We hypothesized that B7-H3, a coinhibitory factor, is expressed by primary breast cancer cells and associated with metastasis to regional tumor-draining lymph nodes.


METHODS
: American Joint Committee on Cancer stage I to III primary breast cancers (n = 82) and normal breast specimens (n = 17) were assessed for B7-H3 expression using paraffin-embedded archival tissues. B7-H3 expression by breast cancer cells was assessed by a quantitative real-time reverse transcription-polymerase chain reaction, and B7-H3 protein expression was evaluated using immunohistochemistry.


RESULTS
: B7-H3 mRNA expression was detected in 32 of 82 (39%) primary breast tumors but not in normal breast tissues (P = 0.0029). B7-H3 expression in primary tumors significantly correlated with increasing tumor size, American Joint Committee on Cancer stage, and lymphovascular invasion (P < 0.0001, P < 0.0001, P = 0.0071). B7-H3 expression was highly correlated to sentinel lymph node and overall number of lymph nodes with metastasis P = 0.003, and P = 0.004, respectively). In a multivariate analysis, B7-H3 mRNA expression of the primary tumor significantly predicted metastasis to regional lymph nodes (P = 0.021, and P = 0.023, respectively). Antibody staining analysis of paraffin-embedded archival tissue breast tumors and flow cytometry of breast cancer cell lines demonstrated B7-H3 protein expression.


CONCLUSIONS
: B7-H3 protein expressed by primary breast cancer cells is a tumor progression factor and is associated with extent of regional nodal metastasis.
Department of Molecular Oncology, John Wayne Cancer Institute, Saint John's Health Center, Santa Monica, CA, USA.
Takaaki
T
Arigami
Norihiko
N
Narita
Ryuichi
R
Mizuno
Linhda
L
Nguyen
Xing
X
Ye
Alice
A
Chung
Armando E
AE
Giuliano
Dave S B
DS
Hoon
D015703:Antigens, CD / Q000096:biosynthesis*; D001365:Axilla; D060887:B7 Antigens; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology*; D005260:Female; D006801:Humans; D008024:Ligands; D008207:Lymphatic Metastasis; D011971:Receptors, Immunologic / Q000096:biosynthesis*
D015703:Antigens, CD; D060887:B7 Antigens; C423237:CD276 protein, human; D008024:Ligands; D011971:Receptors, Immunologic