ALDH1A1 and colorectal cancer: Recent studies have explored the potential prognostic value of a set of colorectal cancer stem cell markers—CD133, LGR5, ALDH1, CD44v6 and SOX2—investigated alone or in association with immune-related cell markers—CD3, CD8, Foxp3 and PD-L1—in 104 stage III colorectal cancer patients [457].