Figure 6.

PI3Kβ inhibitors overcome TMZ resistance in PI3Kβ-high GSCs

The sphere-forming assay was used to measure the self-renewal of PI3Kβ-high VTV103/GSC (A), PI3Kβ-low VTC-056/GSC (B), or NSC (C). Cells were treated with 20 μM TGX-221 (TGX), 10 μM AZD6482 (AZD), or 100 μM TMZ, as well as combinations of TGX/TMZ or AZD/TMZ. Cells were imaged using an inverted microscope. Single or sick cells were indicated by red arrows. Wells with healthy spheres were scored, and percentages of wells with spheres (numbers of wells with spheres/numbers of all wells in each treatment group) were plotted. EOBs were calculated using the Bliss Independence model. Error bars stand for standard deviations derived from three to four independent replicates. Student’s t test was used to determine p values between two groups. ns: not significant. Scale bar: 50 μm.