Moreover, while Nox1 mRNA was sparsely detected in epithelial cells of benign prostate tissue (0.08% of cells in benign areas showed 1–2 mRNA transcript signals) and significantly increased in tumor epithelial cells of adjacent cancer foci (0.55%, p < 0.0001; Fig. 3cd), Nox1 mRNA was not detectable in either the benign or tumor‐associated stroma of prostate tissue specimens (Fig. 3c). Here, NOX1 is linked to cancer.