SOX2 and cholangiocarcinoma: Furthermore, correlation analysis using cholangiocarcinoma datasets from The Cancer Genome Atlas (TCGA-CHOL) showed that WNT pathway genes (AXIN2, CTNNB1, LEF1) positively correlated with TIC signature genes (KIT, SALL4, CD44, SOX2) (Supplemental Figure 2, D–G).