Loss of E-cadherin and catenin expression may be associated with distant and lymph node metastases in breast cancer. Heterogeneity of E-cadherin expression is associated with poor prognosis, suggesting that E-cadherin and catenins may serve as useful prognostic markers for invasive breast carcinoma. Reduction or loss of expression of either E-cadherin or catenins is associated with invasion, metastasis and poor prognosis in several types of human malignancies. We investigated the expression of E-cadherin, and α- and β-catenins by immunohistochemistry in 171 cases of primary invasive breast cancer, and compared the expression with clinicopathological parameters to define the relationship between expression and prognosis. E-cadherin immunoreactive protein was shown to be expressed in 97 cases. Reduction or lack of expression of E-cadherin was associated with distant metastasis. Based on immunohistochemical heterogeneity, E-cadherin-positive tumors were classified into heterogeneous, homogeneous and intermediate types. Interestingly, although patients with heterogeneous type demonstrated the lowest incidence of distant metastasis at diagnosis, they showed a higher incidence of subsequent distant metastasis, after surgery, and a lower survival rate than those with homogeneous type (p<0.05). E-cadherin expression was reduced or negative in metastatic axillary lymph nodes regardless of the expression in the primary tumor, suggesting that changes in E-cadherin expression are associated with not only distant metastasis but also lymph node metastasis. Tumors negative for either α- or β-catenin expression demonstrated a higher incidence of distant metastasis than those expressing both catenins, suggesting that the expression of catenins is involved in breast cancer metastasis. Reduction or loss of E-cadherin and catenin expression may be associated with distant and lymph node metastases in invasive breast cancer, and the heterogeneous type may be associated with poor prognosis.

In this study, we elucidated the cellular localization of somatostatin receptor (SSTR) by immunohistochemistry using an antibody specific for SSTR type 2A (SSTR2A) in various organs of rat and human. SSTR2A expression was basically similar in rat and human, except in the pancreas and adrenal cortex. In the pituitary gland, the posterior lobe and the majority of growth hormone cells and some ACTH and TSH cells expressed SSTR2A. In rat adrenal gland, the zona glomerulosa strongly expressed SSTR2A, whereas zone-specific immunoreactivity was not observed in human. The adrenal medulla moderately expressed SSTR2A in both rat and human. SSTR2A immunoreactivity was observed in islet cells and some ductal cells in human pancreas, and also in acinar cells of rat pancreas. In gastrointestinal (GI) tract, the majority of crypt cells and nerve plexuses strongly expressed SSTR2A. The number of SSTR2A positive cells was much more than that of chromogranin A positive endocrine cells. In the kidney, the glomerular capillaries and collecting tubules, but not proximal tubules, showed immunoreactivity. SSTR2A immunoreactivity was observed not only in endocrine cells but also in non-endocrine cells.