Fig. 5: Ferroptosis suppression by DHCR7 inhibition depends on the activity of sterol synthesis and DHCR7 expression.

a HT1080 cells and OVISE cells were treated with Fer-1 (1 µM), AY9944 (30 nM), Cholesterol-HPβCD inclusion complex, or 7-DHC-HPβCD inclusion complex for 1 h, followed by RSL-3 (0.1 µM) for 24 h. Cytotoxicity was assessed by an LDH release assay. b HT1080, OVISE, and Huh-7 cells were pretreated with Fer-1 (0.5 µM) or AY9944 (30 and 100 nM) for 1 h, and then treated with RSL-3 (0.1 µM) for 24 h. Cell viability was assessed by the MTT assay. c, d Expression of genes involved in cholesterol biosynthesis in human cancer cell lines in the CCLE dataset. c Scatter plot showing expression levels (log2 normalized TPM) of DHCR7 and either HMGCR or SC5D. d Expression score calculated using genes listed in the Cholesterol biosynthesis/Reactome. e Heatmap showing the expression levels of Cholesterol biosynthesis. f TRE-nSREBP-1a–HT1080 cells were treated with DOX (10 ng/mL or 30 ng/mL) for 6 h. The mRNA levels of DHCR7, SC5D, and HMGCR were assessed by real-time RT-PCR analysis. g and h TRE-nSREBP-1a–HT1080 cells were treated with or without RSL3 for 24 h after 6 h of treatment with DOX (30 ng/mL) and AY9944 (100 nM). Cytotoxicity and cell death were assessed by g an LDH release assay and h SYTOX Green. a, b, f, and g Data are means or h representative of (a, b, f, and h) three or g four independent experiments. Statistical significance was calculated using one-way or two-way ANOVA with Tukey’s post hoc test. Data are expressed as dot plots and means ± SEM.