Fig 2: COX-2 inhibitor treatment upregulates the expression of DR4 and DR5 in BT20 and MCF7 spheroids.(A) Flow cytometry histograms showing the effect of 100 µM NS-398 treatment on death receptor expression in BT20 and MCF7 cells cultured as spheroids. (B) Western blot analysis of whole cell lysates from untreated and NS-398 treated BT20 and MCF7 spheroids for DR4 and DR5 expression. (C) Flow cytometry scatter plots showing the effect of NS-398 treatment on the prevalence of CD44hiCD24lo population in BT20 and MCF7 cells cultured as spheroids.

Fig 3: BT20 and MCF7 spheroids have a lower expression of death receptors.(A) Confocal micrographs of BT20 and MCF7 cells cultured as 3D spheroids and 2D monolayer stained with antibodies against DR4 (red), DR5 (red) and EpCAM (green). (Scale bar = 20 µm) (B) Flow cytometry histograms comparing DR4 and DR5 expression in BT20 and MCF7 spheroids and monolayer. (C) Western blot analysis of total DR4 and DR5 expression in cell lysates from BT20 and MCF7 spheroids and monolayer.

Fig 4: CD44hiCD24lo BT20 spheroid cells have a lower expression of DR4 in comparison to non-stem like cells.(A) Confocal micrographs of FACS sorted CD44hiCD24lo cells from BT20 and MCF7 spheroids stained with FITC conjugated CD44 antibody and PE conjugated CD24 antibody (Scale bar = 50 µm) (B) Bright field images of CD44hiCD24lo and non-stem like cells from BT20 and MCF7 spheroids (C) Flow cytometry histograms comparing the expression of death receptors in FACS sorted cells and monolayer cells.