Expression analysis of potential breast-specific molecules (A) reveals that bulk tissue of normal lung (lane 1) expressed SBEM and PDEF, but not MGB1. Detailed examination using laser capture microdissection (lanes 2 to 4) demonstrated that bronchial surface epithelium and bronchial gland cells, but not the peripheral lung, were the source of the expression. In tumors (B), MGB1 expression was specific to breast cancers (B, lanes 9 to 15), with the notable exception of small-cell lung carcinomas (B, lane 8). DW indicates distilled water.