Fig. 2.

a qRT-PCR was performed for cells from hypoxic culture (parental 21% vs 1% O₂), hypoxia mimetic culture (parental +/− CoCl₂) and our HIF1-alpha inducible system (mHIF-YFP-DD +/− TMP). A similar pattern was seen in all conditions. b Following 48 h in hypoxic culture (parental 21% vs 1% O₂), hypoxia mimetic culture (parental +/− CoCl₂) or our HIF1-alpha inducible system (mHIF-YFP-DD +/− TMP) cells were plated in mammosphere culture. A comparable response was seen in all conditions. c Conditioned medium was collected from cells cultured in hypoxia (parental 21% vs 1% O₂) or our HIF1-alpha inducible system (mHIF-YFP-DD +/− TMP) and was used to treat parental cells (MCF7 and MDA-MB-231) for 48 h. These cells were then plated in mammosphere culture. The conditioned medium induced the same hypoxic response as the culture condition from which it came regardless of the cells being treated