Fig. 4

A high-content chemical screen identifies galunisertib as a drug candidate to rescue cell death induced by loss of GLIS3 both in vitro and in vivo. a Schematic representation of the high-content chemical screen. b Chemical structure of galunisertib. c Inhibitory curve of galunisertib. d Immunocyto-chemistry analysis of GLIS3^−/− PP2-β cells treated with DMSO or 10 µM galunisertib. Scale bar = 100 μm, scale bar of high magnification insets = 40 μm. e, f Quantification of the cell death rate (e, the percentage of PI⁺INS⁺ cells in INS⁺ cells, n = 4) and apoptosis rate (f, the percentage of cleaved caspase-3⁺INS⁺ cells in INS⁺ cells, n = 3) of GLIS3^−/− PP2-β cells treated with DMSO or 10 µM galunisertib. Flow cytometry analysis (g) and quantification (h) of early apoptotic cells (the percentage of Annexin V⁺/DAPI⁻ cells) in GLIS3^−/− INS-GFP⁺ PP2-β cells treated with DMSO or 10 μM galunisertib (n = 6). i Relative number of INS⁺ cells in GLIS3^−/− PP2-β cells treated with DMSO or 10 μM galunisertib. Data are normalized to DMSO-treated values (n = 4). j Schematic representation of the in vivo transplantation and drug treatment experiments. k Immunohistochemistry analysis of INS, cleaved caspase-3, and STEM121 in the grafts isolated from vehicle- or galunisertib-treated mice. Scale bar = 100 μm. l Quantification of immunohistochemistry data in j (n = 7). m Quantification of the percentage of apoptotic INS⁺ cells (CAS3⁺INS⁺ STEM121⁺) in the INS⁺ population within the grafts from vehicle- or galunisertib-treated mice (INS⁺STEM121⁺, n = 6). CAS3: cleaved caspase-3. P values by unpaired two-tailed t-test were *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001. The center value is “mean”. Error bar is SEM