A readthrough transcript of the chemokines CCL14 and CCL15 is differentially expressed in human breast cancer.
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 a readthrough transcript of CCL14 and CCL15, CCL14-CCL15, when comparing primary tumors of the breast to the tissue of origin, the normal breast. CCL14-CCL15 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 CCL14-CCL15 in primary tumors of the breast was correlated with overall survival in patients with luminal A cancers, demonstrating a relationship between primary tumor expression of a differentially expressed gene and patient survival outcomes influenced by molecular subtype. These data document a potential role for a readthrough chemokine transcript in human breast cancer.