Expression of stanniocalcin-1 (STC1) in clinical samples and renal cell carcinoma (RCC) cell lines. (A) The mRNA level of STC1 was significantly up-regulated in clear cell renal cell carcinoma (ccRCC) tissues compared with adjacent normal renal tissues, with the greatest expression observed in metastatic tissues. (B) The mRNA expression of STC1 was up-regulated in RCC cell lines compared with HKC-renal tubular epithelial cell line, with the greatest expression observed in metastatic cells. (C) (D) Western blotting showed the changes of protein expression were consistent with these of mRNA in clinical samples and RCC cell lines. (E) Immunofluorescence analysis revealed a significant increase in the intensity of STC1 staining in the cytoplasm of metastatic cell lines. (F) Representative images of STC1 immunohistochemistry staining in non-tumor (NT) tissues, localized and metastatic ccRCC tissues. Scale bar, 100 μm. Quantitative analysis of STC1 protein levels in the cytoplasm in 10 sets of paired NT tissues, localized and metastatic ccRCC tissues (n = 10). *,P < 0.05; **,P < 0.01.