Western analysis of extracts from MCF7 cells, untreated or treated with Estrodiol/EGF (100nM each, together for 30 min) and further treated with calf intestinal phosphatase (CIP), using Phospho-Estrogen Receptor α (Ser167) (D1A3) Rabbit mAb (upper) or Estrogen Receptor α (D8H8) Rabbit mAb #8644 (lower).