Fig. 5: The combination strategy could promote CRPC cell apoptosis by inducing ROS accumulation.

A, B The GSEA results between the groups showed that the functions related to oxidative stress were activated when the drugs were used alone and in combination, and the combined use resulted in higher oxidative stress levels. Transcriptome sequencing used three biological replicates during the sample preparation stage. C–E The results of CM-H2DCFDA showed that the combination strategy could significantly increase the accumulation level of ROS. Data were presented as the mean ± SD from three biological replicates. The Brown–Forsythe test P values were all > 0.05, satisfying the homogeneity of variance assumption. One-way ANOVA with Turkey multiple comparison corrections was applied. F–H The results of TMRE staining showed that the combination strategy could reduce the mitochondrial membrane potential. Data were presented as the mean ± SD from three biological replicates. The Brown–Forsythe test P values were all > 0.05, satisfying the homogeneity of variance assumption. One-way ANOVA with Turkey multiple comparison corrections was applied. I TEM revealed that the combination strategy caused severe damage to mitochondria in CRPC cells, with significant mitochondrial swelling and almost complete disappearance of cristae. The red arrows indicated typical mitochondrial morphology. TEM included three biological replicates during the sample preparation phase. CRPC, castration-resistant prostate cancer; GSEA, gene set enrichment analysis; ROS, reactive oxygen species; TEM, transmission electron microscopy. *, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001; ns not significant.