Transcription profiling of human age-dichotomized ER+ breast tumors

To investigate the biological basis between aging and sporadic breast cancer incidence and prognosis, RNA samples from matched ER+ invasive breast cancers diagnosed in either young (≤45) or old (≥70) women were analyzed by expression microarrays Experiment Overall Design: ER+ breast cancers collected from either young or old women, well matched for other clinical parameters were analyzed using expression microarrays. Age associated tumor subtypes and enrichment of pre-defined gene signatures were identified. Age associated differential expression and an age signature (gene-based classifier) was assessed