Figure 4. HIF-1α involves in promoting breast cancer stem-like cell properties by EMMPRIN-STAT3 signal pathway.
(A) SUM102 and BT474 breast cancer cells were exposed to hrEMMRPIN for 24 h and total protein was extracted from the cells for western blotting. (B) STAT3 knocking down induced changes of breast cancer stem-like cell markers. STAT3 were knocked down in SUM102 and BT474 breast cancer cells by siRNA, and the cells were treated with conditioned medium from fibroblasts 1068SK or Hs578Bst for 3 days, and then the protein were extracted from the cells. The conditioned medium were collected from fibroblasts or the breast cancer cells co-cultured with fibroblasts for 3–5 days. (C) Knocking down of STAT3 decreased the percentage of CD44+CD24− breast cancer cells of BT474 treated with human recombinant EMMPRIN by flow cytometry analysis. (D) Data analysis from C. (E) HIF-1α knocking down induced changes of breast cancer stem cell markers. HIF-1α were knocked down in SUM102 and BT474 breast cancer cells by siRNA. (F) HIF-1α knocking down induced changes of breast cancer stem cell markers by immonofluoresence. (G) HIF-1α knocking down decreased mammosphere formation in breast cancer cells. The data presented were shown as means ± s.d. collected from three independent experiments. **p < 0.01.