In addition, we further determined, using the human protein atlas (HPA) database (https://www.proteinatlas.org/; accessed on 16 February 2021), that the staining intensity for ODC1 in normal colon tissues was either poor or nonexistent, whereas the intensity in colon cancer tissues was mostly moderate or strong (Figure 1b), which suggested that a change in the ODC1 protein could be a target for the chemoprevention of colorectal cancer. This evidence concerns the gene ODC1 and colorectal cancer.