In this study, we proposed to identify alternatively spliced transcripts associated with breast tumors that are under ERBB2 influence by constructing 2 AS-enriched cDNA libraries using RNA sources representative of ERBB2 over-expression: the human breast cell line C5.2 that was previously transfected with 4 copies of full-length ERBB2[42] and a pool of 5 breast carcinoma samples, which demonstrate strong positivity in ERBB2 immunostaining in tumor cell membranes [43]. This evidence concerns the gene ERBB2 and breast carcinoma.