ABSTRACT
BACKGROUND: Breast cancer is the most common cancer and cause of deaths in women around the world. Oncogene amplification usually occurs late in tumor progression and correlates well with aggressiveness of tumor. In fact the function of the S100A4 protein and its role in metastasis is unclear at present. The purpose of the study was to determine the expression of S100A4 protein in the invasion status and metastatic potential of breast cancer by using tissue microarray and to determine its role in breast cancer based on the expression of S100A4 gene product. METHODS: S100A4 protein expression was examined by immunohistochemistry (IHC) using commercially available tissue microarray containing malignant and normal breast tissue cores from 216 patients. RESULTS: S100A4 was absent in normal breast tissues while positive in 45.1% of infiltrating ductal carcinoma (IDC) node negative and 48.8% of infiltrating lobular carcinoma node negative. In paired samples, S100A4 protein was expressed in 13.5% of IDC node positive cases and 35.1% of matched lymph node metastasis. CONCLUSION: S100A4 protein expression appears widely expressed in early and advanced breast cancer stages compared with normal breast. Our study suggests S100A4 may play a role in breast cancer progression and may prove to be an independent marker of breast cancer which appears to be down regulated in more advanced stages of breast cancer.
ABSTRACT
BACKGROUND: Breast cancer is the most common cause of cancer death in the western world. The expression differences of many proteins are associated with breast cancer progression or suppression. The purpose of the study was to determine the expression of nm23 protein in the invasion status and metastatic potential of breast cancer by using tissue microarray and to determine its role in breast cancer based on the expression of nm23 gene product. METHOD: nm23 protein expression was examined by immunohistochemistry (IHC) using commercially available tissue microarray containing malignant and normal breast tissues from 216 patients. RESULTS: a similar percentage of cases showed positive cytoplasmic/nuclear staining for nm23 in normal breast tissue (85.7%), primary breast carcinoma node negative (97.5%) and carcinoma with lymph node metastasis (92.1%). Nuclear localization of staining for nm23 protein was higher in infiltrating ductal carcinoma (IDC) node positive (24.3%) and in matched lymph mode metastasis (18.9%) compared to IDC node negative (4.9%). Strong intensity of cytoplasmic/nucleus staining was observed in IDC node negative (42.6%), in IDC node positive (57.1%), and Infiltrating lobular carcinoma (ILC) node negative (44%) compared to normal breast tissue (16.7%). CONCLUSION: nm23 protein expression appears widely expressed in normal breast, early and advanced breast cancer stages. Interestingly our study found that strong staining intensity and nuclear localization of nm23 protein may prove to be a useful marker of breast cancer progression.
