Abnormal expression of multiple proteins predicts cancer-specific mortality in patients with high-grade non-muscle-invasive bladder cancer treated with transurethral resection

[S100A4, a potential therapeutic target on bladder cancer stem cells]

OBJECTIVE

To observe the effect of S100A4 gene silencing mediated by small interfering RNA (siRNA) on the proliferation of bladder cancer stem cells (CSCs) and their capacity of xenograft tumor formation.

METHODS

MB49 bladder cancer stem cells (MCSCs) were isolated and identified. The differentially expressed protein S100A4 was identified in MCSCs using isobaric tags for relative and absolute quantitation technology (iTRAQ). A siRNA targeting S100A4 was constructed and transfected into MCSCs, and its inhibitory effects on S100A4 expression in MCSCs were assessed with Western blotting and qPCR. The effects of siRNA-mediated S100A4 silencing on the proliferation and xenograft tumor formation ability of MCSCs were observed.

RESULTS

Among the 65 differentially expressed proteins identified by iTRAQ combined with LC/MS/MS, S100A4 protein showed the most distinct differential expression in MCSCs. Transfection of MCSCs with S100A siRNA significantly inhibited the expressions of S100A4 at both mRNA and protein levels, caused obvious suppression of the cell proliferation, and attenuated the xenograft tumor formation ability of the cells in nude mice.

CONCLUSION

S100A4 in MCSCs is associated with the recurrence and metastasis of bladder cancer. S100A4 may serve as a potential therapeutic target for eliminating bladder CSCs.

[S100A4, a potential therapeutic target on bladder cancer stem cells]

OBJECTIVE

To observe the effect of S100A4 gene silencing mediated by small interfering RNA (siRNA) on the proliferation of bladder cancer stem cells (CSCs) and their capacity of xenograft tumor formation.

METHODS

MB49 bladder cancer stem cells (MCSCs) were isolated and identified. The differentially expressed protein S100A4 was identified in MCSCs using isobaric tags for relative and absolute quantitation technology (iTRAQ). A siRNA targeting S100A4 was constructed and transfected into MCSCs, and its inhibitory effects on S100A4 expression in MCSCs were assessed with Western blotting and qPCR. The effects of siRNA-mediated S100A4 silencing on the proliferation and xenograft tumor formation ability of MCSCs were observed.

RESULTS

Among the 65 differentially expressed proteins identified by iTRAQ combined with LC/MS/MS, S100A4 protein showed the most distinct differential expression in MCSCs. Transfection of MCSCs with S100A siRNA significantly inhibited the expressions of S100A4 at both mRNA and protein levels, caused obvious suppression of the cell proliferation, and attenuated the xenograft tumor formation ability of the cells in nude mice.

CONCLUSION

S100A4 in MCSCs is associated with the recurrence and metastasis of bladder cancer. S100A4 may serve as a potential therapeutic target for eliminating bladder CSCs.

INHBA overexpression indicates poor prognosis in urothelial carcinoma of urinary bladder and upper tract

BACKGROUND

Urothelial carcinoma (UC) originating from the bladder (UBUC) and upper urinary tract (UTUC) is the most common type of urinary tract tumor. While its pathogenesis remains obscured. Computerizing a published transcriptomic database of UBUC (GSE31684), we identified Inhibin, Beta A (INHBA) as the most significant upregulated gene associated with tumor progression among those associated with growth factor activity (GO:0008083). We therefore analyzed the clinicopathological significance of INHBA expression in UC.

DESIGN

QuantiGene assay was used to detect INHBA transcript level in 36 UTUCs and 30 UBUCs. Immunohistochemistry evaluated by H-score was used to determine INHBA protein expression in 340 UTUCs and 296 UBUCs. INHBA expression was correlated with clinicopathological features and disease-specific survival (DSS) and metastasis-free survival (MeFS).

RESULTS

Increments of INHBA transcript level was associated with higher pT status in both UTUC and UBUC. INHBA protein overexpression was significantly associated with advanced clinicopathological features in both groups of UC. INHBA overexpression significantly implied inferior DSS (UTUC, P = 0.002; UBUC, P = 0.005) and MeFS (UTUC and UBUC, both P < 0.001) in multivariate analysis.

CONCLUSION

INHBA overexpression implies adverse clinical outcomes for UC, justifying it is a potential prognostic biomarker and a novel therapeutic target in UC.