ABSTRACT
In recent years, salinomycin has been shown to exert an anticancer effect in a variety of tumors; however, its function and mechanism in bladder cancer (BC) remain unclear. This study examined the effect of salinomycin on bladder cancer and analyzed its regulatory mechanism. T24 cells were treated with different concentrations of salinomycin to detect subsequent changes in cell proliferation, apoptosis, oxidative stress, H3K4 methylation, and related gene expression by the CCK8 assay, Edu staining, Tunel staining, ELISA, RT-qPCR, and western blotting, respectively. A KDM1A overexpression plasmid, catalytically inactive KDM1A overexpression plasmid, or short hairpin RNA (shRNA) plasmid was transfected into T24 cells to evaluate their effects. A xenograft tumor model was used to further confirm the anti-tumor effect of salinomycin. Our results showed that salinomycin significantly inhibited cell proliferation, promoted apoptosis, increased MDA levels, decreased SOD levels, induced H3K4 histone methylation, and suppressed KDM1A expression. Furthermore, the sh-KDM1A plasmid had effects similar to those of salinomycin and also activated the unfolded protein response pathway. The KDM1A overexpression plasmid had effects opposite to those of the sh-KDM1A plasmid, and the catalytically inactive KDM1A overexpression plasmid had no effect. Meanwhile, KDM1A overexpression reversed the effects of salinomycin on T24 cells. Finally, in vivo experiments confirmed the above results. In the salinomycin treatment group, tumor growth and KDM1A expression were suppressed and cell apoptosis and UPR were induced, while treatment with the KDM1A overexpression plasmid produced the opposite effects. Collectively, our study revealed that salinomycin suppressed T24 cell proliferation and promoted oxidative stress and apoptosis by regulating KDM1A and the UPR pathway. Supplementary Information: The online version contains supplementary material available at 10.1007/s10616-022-00546-y.
ABSTRACT
OBJECTIVE: To explore the effect of salinomycin on the metastasis and invasion of bladder cancer cell line T24 by regulating the related protein expression in the process of epithelial-mesenchymal transition (EMT), and to provide experimental basis for the treatment of urological tumors. METHODS: The bladder cancer cell line T24 was cultured in vitro. The rat bladder tumor model was established in vivo. The rats were randomized into two groups, among which the rats in the experiment group were given intraperitoneal injection of salinomycin, while the rats in the control group were given intraperitoneal injection of normal saline. The change of tumor cells in the two groups was observed. Transwell was used to detect the cell migration and invasion abilities, Real-time PCR was used to detect the expression of mRNA, while Western-blot was utilized for the determination of the expressions of E-cadherin and vimentin proteins. RESULTS: The metastasis and invasion abilities of serum bladder cancer cell line T24 after salinomycin treatment in the experiment group were significantly reduced when compared with those in the control group, and the tumor metastasis lesions were decreased from an average of 1.59 to 0.6 (P < 0.05). T24 cell proliferation in the experiment group was gradually decreasing. T24 cell proliferation at 48 h was significantly lower than that at 12 h and 24 h (P < 0.05). T24 cell proliferation at 24 h was significantly lower than that at 12 h (P < 0.05). T24 cell proliferation at each timing point in the experiment group was significantly lower than that in the control group (P < 0.05). The serum mRNA level and E-cadherin expression in the tumor tissues in the experiment group were significantly higher than those in the control group, while vimentin expression level was significantly lower than that in the control group (P < 0.05). CONCLUSIONS: Salinomycin can suppress the metastasis and invasion of bladder cancer cells, of which the mechanism is probably associated with the inhibition of EMT of tumor cells.
