CD151, a master regulator of laminin-binding integrins (A6B4, A6B1, and A3B1), assembles these integrins into complexes called tetraspanin-enriched microdomains. CD151 protein expression is elevated in 31% of human breast cancers and is even more elevated in high-grade (40%) and estrogen receptor–negative (45%) subtypes. The latter includes triplenegative (estrogen receptor, progesterone recept...