The prognostic value of BCAR1 in patients with primary breast cancer.

Purpose: BCAR1, the human homologue of the rat p130Cas protein, was identified in a functional screen for human breast cancer cell proliferation resistant to antiestrogen drugs. Here, we study the prognostic value of quantitative BCAR1 levels in a large series of breast cancer specimens.

Experimental Design: A specific ELISA was developed to measure BCAR1 protein levels in 2593 primary breast tumor cytosols.

Development of an ELISA for measurement of BCAR1 protein in human breast cancer tissue.

Background: High concentrations of breast cancer anti-estrogen resistance 1 (BCAR1) protein measured by Western blotting in primary breast tumor cytosols are associated with early disease progression and failure of tamoxifen therapy. The aim of the present study was to develop an ELISA to measure BCAR1 quantitatively in extracts of human breast cancer tissue.

Methods: A recombinant fragment of BCAR1 (the human homolog of murine p130Cas) was produced in bacterial M15 cells, purified, and injected into chickens and rabbits.