Fig. 4: S1PR1 deletion promotes CDDP-induced senescence in ovarian cancer cells.
From: S1PR1 regulates ovarian cancer cell senescence through the PDK1-LATS1/2-YAP pathway
A Immunohistochemistry analysis of the expression of S1PR1 in CDDP (cisplatin) chemotherapy-insensitive ovarian cancer tissues (CDDP-resistant) and chemotherapy-sensitive ovarian cancer tissues (CDDP-sensitive; left) and quantitative analysis (right). Scale bar, 50 µm. Values represent mean ± SD of three independent experiments. One-way ANOVA; ***p < 0.001. B IC50 values of A2780-S (CDDP-sensitive) and A2780-CP (CDDP-resistant) ovarian cancer cells. C CCK8 cell proliferation assay analysis of the proliferative propensity after treatment with increasing concentrations of cisplatin. Values represent mean ± SD of three independent experiments. One-way ANOVA; *p < 0.05, ***p < 0.001. D Western blot analysis of the expression of S1PR1, LATS1, LATS2, YAP, p-YAP, p-PDK1, lamin B1, P62, IGFBP7, and PAI-1 in A2780-S (CDDP-sensitive) and A2780-CP (CDDP-resistant) ovarian cancer cell lines. GAPDH was used as control. E, F β-galactosidase assay analysis of the effect of CDDP (0.125 µg/mL) on senescence in wild-type and S1PR1 knockout ovarian cancer cells. Scale bar, 50 µm. Values represent mean ± SD of three independent experiments. One-way ANOVA; *p < 0.05, **p < 0.01, ***p < 0.001. G, H Western blot analysis of expression levels of PDK1, MST1, IGFBP7, p-YAP, and PAI-1 in wild-type ES-2 cells and S1PR1 knockout ES-2 cells after CDDP treatment (0.125 µg/mL). Values represent mean ± SD of three independent experiments. One-way ANOVA; ***p < 0.001. GAPDH was used as control. I ELISA analysis of IL-6 expression in S1PR1 knockout ES-2 cells before and after CDDP treatment (0.125 µg/mL). Values represent mean ± SD of three independent experiments. Student’s t-test; **p < 0.01, ***p < 0.001. J q-PCR analysis of LATS1/2, YAP and P21 expression in wild-type ES-2 cells and S1PR1 knockout ES-2 cells after CDDP treatment (0.125 µg/mL). Values represent mean ± SD of three independent experiments. One-way ANOVA; *p < 0.05, **p < 0.01, ***p < 0.001. K The effect of S1PR1 knockdown on cisplatin-induced apoptosis of ovarian cancer cells was analyzed by flow cytometry. Data (each cell line experiment was repeated in triplicate) are presented as mean ± SD. One-way ANOVA; **p < 0.01.
