Immunohistochemical study of the BCAR1/p130Cas protein in non-malignant and malignant human breast tissue.

Abstract

BCAR1/p130Cas is a docking protein involved in intracellular signaling pathways and in vitro resistance of estrogen-dependent breast cancer cells to antiestrogens. The BCAR1/p130Cas protein level in primary breast cancer cytosols was found to correlate with rapid recurrence of disease. A high BCAR1/p130Cas level was also associated with a higher likelihood of resistance to first-line tamoxifen treatment in patients with advanced breast cancer. Using antibodies raised against the rat p130Cas protein, we determined by immunohistochemical methods the BCAR1/p130Cas localization in primary breast carcinomas, in tumors of stromal origin, and in non-neoplastic breast tissues. The BCAR1/p130Cas protein was detected in the cytoplasm of non-malignant and neoplastic epithelial cells and in the vascular compartment of all tissue sections analyzed. Immunohistochemistry demonstrated variable intensity of BCAR1/p130Cas staining and variation in the proportion of BCAR1/p130Cas-positive epithelial tumor cells for the different breast carcinomas. Double immunohistochemical staining for BCAR1/p130Cas and estrogen receptor confirmed coexpression in non-malignant luminal epithelial cells and malignant breast tumor cells. The stromal cells in non-malignant tissues and tumor tissues as well as breast tumors of mesodermal origin did not stain for BCAR1/p130Cas. This immunohistochemical study demonstrates a variable expression of BCAR1/p130Cas in malignant and non-malignant breast epithelial cells, which may be of benefit for diagnostic purposes.

• Authors: S van der Flier, T H van der Kwast, C J Claassen, M Timmermans, A Brinkman, S C Henzen-Logmans, J A Foekens, L C Dorssers
• Journal: The International journal of biological markers (Int J Biol Markers) 2001 Jul-Sep Vol. 16 Issue 3 Pg. 172-8 ISSN: 0393-6155 [Print] United States
• PMID: 11605729 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• BCAR1 protein, human
• Crk-Associated Substrate Protein
• Phosphoproteins
• Proteins
• Retinoblastoma Protein
• Retinoblastoma-Like Protein p130

Topics

• Adult
• Breast (chemistry)
• Breast Neoplasms (blood supply, pathology)
• Carcinoma, Intraductal, Noninfiltrating (pathology)
• Crk-Associated Substrate Protein
• Epithelial Cells (cytology, pathology)
• Female
• Humans
• Immunohistochemistry
• Middle Aged
• Neoplasm Invasiveness
• Phosphoproteins (analysis)
• Proteins
• Retinoblastoma Protein (analysis)
• Retinoblastoma-Like Protein p130
• Stromal Cells (cytology, pathology)