Gene expression profile of purified tumor cells from primary breast cancer tumor tissues and metastatic lymph nodes

Gene expression profiling of whole tumor tissues consists of a heterogeneous population of tumor and stromal cells. We performed gene expression profiling of flow cytometry purified tumor cells from primary breast tumor tissues and metastatic lymph nodes in order to segregate tumor signatures from stromal signatures. The goal of this set of expression profiles was to understand the underlying mechanism of lymph node metastatic processes by comparing primary breast tumor cell gene expression profiles with that of lymph node metastatic tumor cells. Keywords: breast cancer, lymph node metastasis Gene expression was performed on 14 primary breast tumors and 6 metastatic lymph node samples, of which there were 3 paired tissues. Common universal human reference design. 20 samples replicated twice as dye swaps generating 40 arrays.