Correlation of immunoglobulin G expression and histological subtype and stage in breast cancer.

PloS one

PubMedID: 23554916

Yang B, Ma C, Chen Z, Yi W, McNutt MA, Wang Y, Korteweg C, Gu J. Correlation of immunoglobulin G expression and histological subtype and stage in breast cancer. PLoS ONE. 2013;8(3):e58706.
INTRODUCTION
Recently, growing evidence indicates that immunoglobulins (Igs) are not only produced by mature B lymphocytes or plasma cells, but also by various normal cells types at immune privileged sites and neoplasm, including breast cancer. However, the association of breast cancer derived IgG with genesis and development of the disease has not yet been established.

METHODS
In this study we examined the expression of IgG in 186 breast cancers, 20 benign breast lesions and 30 normal breast tissues. Both immunohistochemistry with antibodies to Ig? (immunoglobulin G ? light chain) and Ig? (immunoglobulin G heavy chain) and in situ hybridization with an antisense probe to IgG1 heavy chain constant region gene were performed. Various clinicopathological features were also analyzed.

RESULTS
We found that IgG is specifically expressed in human breast cancer cells. Both infiltrating ductal carcinoma and infiltrating lobular carcinoma had significantly greater numbers of Ig? and Ig? positive cancer cells as compared with medullary carcinoma, carcinoma in situ, and benign lesions (all p<0.05). In addition, IgG expression was correlated with breast cancer histological subtypes (p<0.01) and AJCC stages (p<0.05), with more abundance of IgG expression in more malignant histological subtypes or in more advanced stage of the disease.

CONCLUSIONS
IgG expression in breast cancer cells is correlated with malignancy and AJCC stages of the cancers. This suggests that breast cancer derived IgG may be associated with genesis, development and prognosis of the cancer.