Expression and clinical significance of microRNA-21, maspin and vascular endothelial growth factor-C in bladder cancer

Abstract

The present study aimed to explore the expression and clinical significance of microRNA-21 (miR-21), maspin and vascular endothelial growth factor C (VEGF-C) in bladder cancer (BC). A total of 53 BC samples and 12 normal bladder tissue samples were collected. Total messenger RNA (mRNA) was extracted, and reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) was used to evaluate the expression of miR‑21 and maspin in BC and normal bladder tissues. Immunohistochemistry was used for the detection of maspin and VEGF‑C protein expression. Furthermore, the correlations between these molecules and certain clinicopathological parameters were investigated, and survival analysis was performed to assess their prognostic significance. miR‑21 mRNA expression and VEGF‑C protein expression were increased in BC tissues compared with those in normal bladder tissues, whereas maspin mRNA and protein expression levels in BC tissues were significantly decreased (P<0.01). miR‑21, maspin and VEGF‑C expression were significantly associated with the stage, grade and lymph node metastasis of BC (P<0.05), but not the other clinicopathological features evaluated. There was a marked inverse correlation between the mRNA expression of miR‑21 and maspin, with a coefficient of ‑0.978 (P<0.001). Similarly, there was a significant inverse correlation between the protein expression of maspin and VEGF‑C, with a coefficient of ‑0.589 (P<0.001). Overexpression of miR‑21 and VEGF‑C, as well as decreased maspin expression, were associated with a poorer prognosis. These results suggested that upregulation of miR‑21, decreased maspin expression and enhanced VEGF‑C in BC may promote tumor progression. miR‑21, maspin and VEGF-C may therefore have significant roles as biomarkers for prognosis and as therapeutic targets of BC.