Fig. 5

Comparative analyses of N-glycoproteomics and proteomics between ESCC and paired normal tissue. A Number of N-glycosylation sites identified per protein in N-glycoproteomics analysis. B Overview of quantified proteins and N-glycoproteins in different stage of ESCC. C The overlap of the proteins identified in both proteomics and N-glycoproteomics. D Intensity distribution of all glycosites only identified in the N-glycoproteomics data (red bars) overlaid with that of N-glycosites whose corresponding proteins were also identified in the proteomics data (blue bars). E Log2 ratio distributions for N-glycosites analyzed, the value greater than 0.584 or less than − 0.584 were considered to be significant. F Heat map of 37 common proteins that exhibited significant up-regulation in all eight comparisons and down-regulation in more than four comparisons. Color represents the expression levels of proteins, among which red color denotes the high expression while blue color denotes the low expression level. G Number of N-glycosylation sites identified in different samples