Differential expression of transmembrane protein 220 in cancers of the breast.
Breast cancer affects women at relatively high frequency (1). We mined published microarray datasets (2, 3) to determine in an unbiased fashion and at the systems level genes most differentially expressed in the primary tumors of patients with breast cancer. We report here significant differential expression of the gene encoding the transmembrane protein 220, TMEM220, when comparing primary tumors of the breast to the tissue of origin, the normal breast. TMEM220 mRNA was present at significantly lower quantities in tumors of the breast as compared to normal breast tissue. Analysis of human survival data revealed that expression of TMEM220 in primary tumors of the breast was correlated with overall survival in patients with HER2+ subtype cancers, demonstrating a relationship between primary tumor expression of a differentially expressed gene and patient survival outcomes influenced by molecular subtype. TMEM220 may be of relevance to initiation, maintenance or progression of cancers of the female breast.