Fig. 7

CDH1 mRNA is downregulated in kidney tumors and the downregulation potentially results from promoter methylation. A, The CDH1 mRNA levels are significantly decreased in 3 of the 4 subtypes of kidney cancer: m2 (n = 85), m3 (n = 93), and m4 (n = 85) and remain unchanged in m1 (n = 145) compared to the normal tissues (n = 100) (grey, normal; red, carcinoma). B, CDH1 mRNA is significantly downregulated across the major stages of kidney carcinoma with a decrease in CDH1 mRNA between stage 2 and stage 3 (p-value = 0.00025). C, Most kidney carcinoma cell lines exhibit low or no CDH1 mRNA expression. D, CDH1 promoter methylation in kidney carcinoma (n = 324) is significantly higher than in the normal tissues (n = 160). E, CDH1 promoter methylation is significantly increased in stage 1 (n = 160), stage 2 (n = 31), stage 3 (n = 73), and stage 4 (n = 58) compared to the normal tissues (n = 160). F, E-cad protein expression is significantly decreased in stage 1 (n = 52), stage 2 (n = 13), stage 3 (n = 33), and stage 4 (n = 12) of kidney carcinoma compared to the normal tissues (n = 84). G, E-cad protein expression is significantly decreased in stage 1 (n = 4), stage 2 (n = 85), stage 3 (n = 35), and stage 4 (n = 7) of pancreatic cancer compared to the normal tissues (n = 74). *, p < 0.05, **, p < 0.01