LET was the only lncRNA that was downregulated more than 2 folds in GEM-treated xenografts derived from both T24 and 5637 cells. The array results were further validated in these cell lines treated with or without GEM. reduced lncRNA-LET increased the NF90 protein stability, which in turn repressed biogenesis of miR-145 and subsequently resulted in accumulation of CSCs evidenced by the elevated levels of stemness markers HMGA2 and KLF4. UBC patients which displayed lower expression levels of lncRNA-LET and miR-145 had a reduced survival rate, whereas TGFB1 expression level did not show significant difference in clinical outcome.