To successfully capture EpCAM-negative or -low breast cancer cells, different antibodies specific for cell surface proteins (Trop2, CD49f, CD146, CK8, c-Met, CD44, CD47, AQP5, ADAM8, TEM8) as well as ECM molecules (laminin, collagen I, HA) were tested on breast cancer cell lines with different EpCAM expression levels. The gene discussed is CD44; the disease is breast cancer.