Fig. 6
Integrin α2β1-silencing inhibits tumor cell metastasis in a mouse model for breast cancer lung metastasis. a The MCF-7 cells were transfected with the lentivirus vector containing interference sequences against integrin α2β1 to obtain the integrin α2β1-interfering MCF-7 cells (Si-MCF-7). Si-MCF-7 cells or MCF-7 cells (1.5 × 106 cells/100 μl PBS) with or without co-incubating with platelets were intravenously injected into nude mice (n = 5 in each group). HE staining images and the percentage of lung tumor area were determined. b Following the treatment of anti-AK7 for 30 min, the platelets were co-incubated with MCF-7 cells for 40 h (the MCF-7 + platelet/AK7 group). The co-incubation between anti-AK7-untreated platelets and MCF-7 cells was the control (the MCF-7 + platelet group). The tumor cells (1.5 × 106 cells/100 μl PBS) were intravenously injected into the lateral tail vein of immunodeficient nude mice (n = 5 in each group). c The protein expression of pSmad3 and β-catenin in lung tumors. d The mRNA expression of tgfb1, Snail and Slug in lung tumors. e MDA-MB-231 cells were co-incubated with platelets for 40 h (the MDA-MB-231 + Platelet group). Following the simultaneous inhibition of surface integrin α2β1, MDA-MB-231/AK7 cells were co-incubated with platelet/AK7 for 40 h (the MDA-MB-231/AK7 + platelet/AK7 group). MDA-MB-231 cells cultured in the normal medium was the control (the MDA-MB-231 group). The tumor cells (1 × 106 cells/100 μl PBS) were intravenously injected into the lateral tail vein of immunodeficient nude mice (n = 5 in each group). Scale bar = 100 μm. **p < 0.01, ##p < 0.01