Quantification of NRP-1 Expression in OSCC and OPSCC

H&E-stained and IHC-stained glass slides were digitalized at 40× using the Leica Aperio AT2 slide scanner (Leica Biosystems, Wetzlar, Germany) [23 (link)]. WSI images in .svs file format were analyzed with the QuPath platform. Classification was performed applying a Random Tree classifier [24 (link)]. The staining vector signal intensity was assessed and quantified to obtain a H-Score for NRP-1 tissue expression in both OSCC and OPSCC samples. NRP-1 H-Score values were categorized for each tumor site (OSCC and OPSCC) into low and high-expression groups; the threshold for categorization was selected via ROC curve analysis for the OS (Overall Survival) outcome (Figure 1). For TCGA dataset analysis, data were retrieved from the TCGA website, and mRNA levels of the NRP1 gene were analyzed and thresholded using kmplot.com analysis tools [25 (link)] (Last access on 14 July 2021).