As shown in Fig. 4A, all patient-derived CAFs showed a significant upregulation of Nox4 mRNA expression compared to the normal fibroblasts (RMFs), in agreement with the Oncomine analysis shown in Fig. 3B. These CAFs were isolated from breast carcinoma tumors of varying molecular subtypes and clinical stages (I to III), implying that Nox4 upregulation is a common feature in breast CAFs and that activation of this gene persisted throughout various stages. This evidence concerns the gene NOX4 and breast carcinoma.