CD44 and Familial prostate cancer: Studies in prostate cancer show that prostate cancer stem-like cells (PCSCs) are isolated from various experimental and clinical sources of prostate cancer by various methods, including low-adhesion or suspension 3D-cultures based on their anchorage-independent growth feature and antibody-based fluorescence-activated cell sorting (FACS) based on their unique expression of cell surface biomarkers (e.g., CD44, CD133, integrin α2β1) [8, 9].