Fig 2: CEP55 expression is linked to a bad prognosis in PCa.A–F, expression levels of CEP55 in relation to clinicopathological parameters, including T stage, N stage, residual tumor, PSA level, age, and Gleason score, based on the TCGA-PRAD cohort. G, ROC curve analysis of CEP55 for the diagnosis of PCa. H, time-dependent ROC analysis evaluating the predictive value of CEP55 for 1-, 3-, and 5-year PFI in PCa individuals. I, Kaplan–Meier survival analysis of PFI in individuals with upregulated versus downregulated CEP55 expression. J, construction of a nomogram integrating CEP55 expression and independent clinical risk factors (T stage, M stage, PSA level, residual tumor, and age) for forecasting 1-, 3-, and 5-year PFI in PCa individuals. K, calibration curves assessing the agreement between predicted and observed survival probabilities based on the nomogram model. The data are presented as the mean ± SD. Unpaired t tests were employed to compare two groups. ∗p < 0.05; ∗∗p < 0.01; and ∗∗∗p < 0.001. CEP55, centrosomal protein 55; PCa, prostate cancer; PFI, progression-free interval; PRAD, prostate adenocarcinoma; PSA, prostate-specific antigen; ROC, receiver operating characteristic; TCGA, The Cancer Genome Atlas.

Fig 3: CEP55 is overexpressed in PCa tissues and cell lines.A, pan-cancer analysis of CEP55 expression across TCGA datasets. B, comparison of CEP55 expression between tumor and neighboring healthy tissues in the TCGA-PRAD cohort. C and D, CEP55 concentrations in PCa tissues compared with healthy tissues based on GEO datasets GSE8511 and GSE46602. E and F, WB and qRT-PCR analyses of CEP55 expression in tumor and neighboring healthy tissues from clinical PCa specimens. G and H, WB and qRT–PCR analyses of CEP55 expression in RWPE-1 and PCa cell lines (LNCaP, DU145, and PC3). The data are presented as the mean ± SD. Unpaired t tests were employed to compare two groups. One-way ANOVA with Tukey's test was used for comparisons involving more than two groups. ∗p < 0.05; ∗∗p < 0.01; and ∗∗∗p < 0.001. CEP55, centrosomal protein 55; GEO, Gene Expression Omnibus; PCa, prostate cancer; PRAD, prostate adenocarcinoma; qRT–PCR, quantitative RT–PCR; TCGA, The Cancer Genome Atlas; WB, Western blot.

Fig 4: Inhibition of the TPX2–AURKA interaction suppresses CEP55-induced stimulation of the PI3K–AKT pathway and ferroptosis-associated proteins.A, WB analysis was performed to determine the protein levels of AURKA, p-AURKA, AKT, p-AKT, mTOR, p-mTOR, SLC7A11, and GPX4 in PC3 cells overexpressing CEP55 with or without treatment of the AURKA–TPX2 binding inhibitor CAM2602 (20 μM). B, CCK-8 assay was conducted to assess cell proliferation in PC3 cells overexpressing CEP55 with or without CAM2602 treatment. C, a transwell invasion assay was carried out to determine the invasive capability of PC3 cells overexpressing CEP55 with or without CAM2602 treatment. Unpaired t tests were employed to compare two groups. One-way ANOVA with Tukey's test was used for comparisons involving more than two groups. ∗p < 0.05. CCK-8, Cell Counting Kit-8; CEP55, centrosomal protein 55; GPX4, glutathione peroxidase 4; mTOR, mechanistic target of rapamycin; p-AURKA, phosphorylated aurora kinase A; WB, Western blot.

Fig 5: CEP55 promotes resistance to ferroptosis through the regulation of TPX2 in PCa cells.A, GSEA was performed to examine the link between CEP55 expression and the ferroptosis pathway. B and C, PC3 cells were treated with the ferroptosis inducers, Erastin and RSL3, and the IC50 values were determined to assess drug sensitivity following CEP55 overexpression or knockdown. D, WB analysis was utilized to observe the level of ferroptosis-associated proteins (SLC7A11 and GPX4) after CEP55 knockdown and TPX2 overexpression. E, WB analysis was utilized to detect the expression of SLC7A11 and GPX4 after CEP55 overexpression and TPX2 knockdown. F, MDA levels were assessed via a commercial assay to evaluate lipid peroxidation in PC3 cells with CEP55 knockdown and TPX2 overexpression. G, MDA levels were assessed in PC3 cells with CEP55 overexpression and TPX2 knockdown using the same assay. H, the GS–GSSG ratio was measured to assess the cellular redox state in PC3 cells with CEP55 suppression and TPX2 upregulation. I, the GSH–GSSG ratio was also evaluated in PC3 cells with CEP55 overexpression and TPX2 knockdown. Unpaired t tests were employed to compare two groups. One-way ANOVA with Tukey's test was used for comparisons involving more than two groups. ∗p < 0.05. CEP55, centrosomal protein 55; GPX4, glutathione peroxidase 4; GSEA, gene set enrichment analysis; MDA, malondialdehyde; PCa, prostate cancer; WB, Western blot.