Fig. 1

A representative Principal Component Analysis (PCA) and Orthogonal projections to latent structures-discriminant analysis (OPLS-DA) visualized by S-Plot

PCA of Control vs Low-grade dysplasia when all the proteins were considered for PCA (a) and when only ANOVA passing proteins (p value < 0.05) were considered for PCA (b). Orthogonal projections to latent structures-discriminant analysis (OPLS-DA) visualized by S-Plot (c). 0 to − 1 space contains proteins higher in controls and 0 to + 1 space contains proteins higher in low-grade dysplasia. X-axis is p [1] loadings which tells about the magnitude of variance and Y-axis is p(Corr) [1] which tells about the reliability of the predictive variance. A cutoff of > + 0.7 or < − 0.7 for p(Corr) [1] was used to find significantly different proteins between the groups