The downregulated proteins in this group such as Casp3 and Tlr4 have important roles in apoptosis and immunity, while others, such as S100A9 and Akt1 have roles that are closely entwined with the aforementioned proteins, but also have various other substrates and are important for cell transformation and the progression of colorectal cancer (Dihlmann et al., 2005; Duan et al., 2013). This evidence concerns the gene S100A9 and colorectal cancer.