S100A1 and colon adenocarcinoma: However, S100A1, S100A4, S100A8, S100A9, S100A12, S100A13, S100B, and S100Z were downexpressed in COAD when compared with READ (see Figure 2), of which S100A1 and S100B expression levels were particularly lower than the levels of the other S100 genes in CRC tissues (see Figure 3).