Fig. 2

CMTM4 is frequently downregulated in ccRCC tissues and cell lines. a CMTM4 expression in the tumour (T) and paired adjacent non-tumour (N) tissues was detected by western blotting. The results of three representative paired tissues are shown. β-actin was used as an internal standard. b The relative CMTM4 expression level in all 61 patients was calculated for the tumour versus paired adjacent non-tumour tissue (T/N) according to the western blotting result and represented as a dot for each sample. CMTM4 was considered to be significantly downregulated only if the calculated fold change was less than 0.5 in the tumour tissue compared to the matched adjacent non-tumour tissue. CMTM4 expression was further examined by immunohistochemistry (c) and qRT-PCR (d) in representative samples. For qRT-PCR the CMTM4 expression level in the 2# tumour tissue was set as 1, and GAPDH was used as the internal control. e CMTM4 expression in the normal renal tubular epithelial line HK-2 and the ccRCC cell lines 786-O and A498 was detected by western blotting. β-actin was used as an internal standard. N, normal kidney tissue