Fig. 5. SCD1 affected cell stemness via Hippo–YAP pathway and cell-cycle-associated pathway.

a GSEA analysis indicated significantly enhanced expression of Hippo and cell-cycle pathway genes in gastric cancer from the TCGA database. b YAP and TEAD1 expressions were positively correlated with SCD1 protein expression (statistical significance was evaluated by Pearson’s correlation test). c Suppression of SCD1 expression increased the apoptosis rates of HSC034 cells. d The SCD1 downregulation by siRNA knockdown or A939572 led to a significant increase in the G0–G1 phase and a decrease in the S phase, respectively. e Western blotting assays showed a significant decrease in the Hippo/YAP pathway key proteins, YAP, p-YAP and TEAD1, and the cell-cycle-dependent protein, cyclin D1 after SCD1 downregulation. f qRT-PCR assay showed transcriptional decline in YAP and TEAD1 mRNA after SCD1 downregulation. g, h The sphere-forming and cell invasion ability of HSC034 cells were impaired by SCD1 or YAP knockdown, which could be partially reversed by YAP overexpression (scale bar, 25 μm in red). i Representative images of immunohistochemical staining (IHC) showed weakened nucleus YAP expression when SCD1 is negatively expressed (scale bar, 10 μm in black and 25 μm in red). j Nuclear YAP expression was more significantly decreased, whereas cytoplasmic YAP levels were slightly reduced after SCD1 knockdown. Error bars indicate standard deviation (SD) of the mean value. *p < 0.05, **p < 0.01 and ***p<0.001, respectively, t test.