GSEA suggested that the genes significantly positively related to the expression of PITX2 were enriched in squamous-type PDACs, while the genes significantly negatively related to PITX2 were enriched in classic-type PDACs, which also indicated that the upregulated expression of PITX2 was related to the squamous type, and the downregulation was related to the classic type in Moffitt PDX and primary tumor or Nicole’s PDX data (Figure 1B‒D). This evidence concerns the gene PITX2 and neoplasm.