Differential expression of hematological and neurological expressed 1 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 hematological and neurological expressed 1, HN1, when comparing primary tumors of the breast to the tissue of origin, the normal breast. HN1 was also differentially expressed in the tumor cells of patients with triple negative breast cancer. HN1 mRNA was present at significantly higher quantities in tumors of the breast as compared to normal breast tissue. Analysis of human survival data revealed that expression of HN1 in primary tumors of the breast was correlated with overall survival in patients with luminal A subtype cancer. HN1 may be of relevance to initiation, maintenance or progression of cancers of the female breast.