Identification of differentially expressed genes in breast cancer.

A number of genes differentially expressed in breast cancer were isolated using a subtractive cloning technique. DNA sequence analysis and GenBank searches of T4F10, T2H7, and T2E5 cDNA clones found them to be identical with E2A, MSS1, and SEC13R genes. Their expression in a variety of primary breast tumor and cancer cell lines was compared with c-ERB-B2 and pS2 by Northern blot analysis. In breast cancer cell lines, the genes that we isolated are more frequently expressed than the previously described c-ERB-B2 and pS2.