Efforts to measure tumor EPO receptor (EPOR) are limited by the promiscuity of EPOR antibodies, and concerns as to whether EPOR mRNA measurements are confounded by heterogeneity of tumor vasculature, a known EPOR source.
In 50 clinical specimens of breast carcinoma, we report high levels of EPO and EPOR associated with malignant cells and tumor vasculature but not with normal breast, benign papilloma, or fibrocystic tissue.