Figure 6

The combination of MM-121 and trastuzumab significantly inhibits proliferation and induces apoptosis of trastuzumab-resistant BT474-HR20 breast cancer cells in vivo . The tumors obtained from the animal studies described above were evaluated by IHC analysis of Ki67 and cleaved caspase-3. A, Data show the representative images of the immunostaining of Ki67 and cleaved caspase-3 (Cleaved Casp-3). B, The IHC slides were observed by two independent personnel. The tumor cells with positive staining of Ki67 or cleaved caspase-3 were counted from three randomly selected areas in each slide. The three areas were first identified by scanning the entire slide at ×10 magnification, and then the positive staining cells were counted at ×20 magnification using an Olympus BX40 Microscope. The bar graphs show the average of positive staining cells in each field. Bars, SD. The combinatorial treated mice had significantly fewer cells stained positive for Ki67 and more cells stained positive for cleaved caspase-3 than control mice or single Ab treated mice, P < 0.008 and P < 0.05, respectively.