[Expression and significance of phosphorylated Girdin in breast cancer]

To detect the expression of phosphorylated girdin (p-girdin) in breast cancer and its association with pathological characteristics and molecular subtypes of breast cancer.

Immunohistochemical SP staining was used to investigate the expression of p-girdin in 27 cases of lobular hyperplasia of mammary gland, 61 cases of ductal carcinoma in situ (DCIS), and 94 cases of non-special type invasive carcinoma (IDC-NOS) of breast.

p-girdin was located in the cell cytoplasm and (or) nuclei in breast cancer. There was statistically a very significant difference among lobular hyperplasia, DCIS and IDC-NOS (χ2=26.724, P<0.001). Its cytoplasmic and nuclear reactivity were 25.9% (7/27), 39.3% (24/61), and 66.0% (62/94), respectively. The expression of p-girdin was positively associated with pathologic stage (r=0.204, P=0.049), lymph node metastasis (r=0.212, P=0.041) and HER2/neu (r=0.248, P=0.016). But no significant association was identified between p-girdin expression and histological grade (r=-0.015, P=0.918), age of patients (r=-0.011, P=0.918), tumor size (r=0.075, P=0.471), ER(r=0.071, P=0.498), PR (r=-0.050, P=0.634). Mann-Whitney test showed that p-girdin expression in luminal A, luminal B, triple negative and HER-2(+) type was significantly different (χ2=14.017, P=0.003). Among the four types, its positive rate was 55.8% (24/43), 95.8% (23/24), 66.7% (10/15), and 41.7% (5/12), respectively.

p-Girdin expression is closely correlated with the malignant progression of breast cancer. Its expression may have clinical value as a new target for the treatment of breast cancer.