The increased expression level of this gene is associated with HER-2/neu proto-oncogene overexpression. Amplification and resulting overexpression of this proto-oncogene are found in approximately 30% of human breast and 20% of human ovarian cancers. Alternatively spliced variants encoding different isoforms have been identified for this gene. [provided by RefSeq, Dec 2010] see less The increased expression level of this gene is associated with HER-2/neu proto-oncogene overexpression. Amplification and resulting overexpression of this proto-oncogene are found in approximately 30% of human breast and 20% of human ovarian cancers. Alternatively spliced variants encoding different isoforms have been identified for this gene. [provided by RefSeq, Dec 2010]