Breast Cancer Anti-Estrogen Resistance 3 (BCAR3)

BCAR3 encodes a component of intracellular signal transduction that causes estrogen-independent proliferation in human breast cancer cells. The protein contains a putative src homology 2 (SH2) domain, a hall mark of cellular tyrosine kinase signaling molecules, and is partly homologous to the cell division cycle protein CDC48.The deduced 825-amino acid BCAR3 protein contains a putative Src homology 2 (SH2) domain and sequences homologous to yeast CDC48. Northern blot analysis detected abundant expression of a 3.4-kb BCAR3 transcript in heart, placenta, skeletal muscle, spleen, prostate, testis, ovary, small intestine, colon, fetal kidney, and several cancer cell lines, but not in nonmalignant breast tissue; a 6-kb BCAR3 transcript was also detected in skeletal muscle and heart.