Fig. 3.

pINDUCER11 (miR-RUG) elicits robust inducibility in the mouse mammary gland and mammary tumors in vivo. (A) Mouse mammary glands were excised, dispersed into single-cell suspension, transduced with pINDUCER11 (miR-RUG), and retransplanted orthotopically into the cleared fat pad of syngeneic mice with or without dox. After 4 wk, mammary glands were explanted and visualized by fluorescence microscopy as indicated. (B) p53^−/− mouse mammary tumors were excised, dispersed into single-cell suspension, transduced with pINDUCER11, sorted for eGFP fluorescence, and retransplanted orthotopically into syngeneic mice. Upon tumor formation (>300 mm³), mice were treated with or without dox for 7 d, and tumors were explanted and visualized by phase or fluorescence microscopy as indicated. (C) MDA-MB-231 human breast cancer cells were transduced with pINDUCER11 and transplanted into the mouse mammary gland. Mice were treated with or without dox for 28 d. Tumors were dispersed into single-cell suspension and analyzed for fluorescence (eGFP and tRFP) by flow cytometry.