With FGF treatment, the ratio of the signal in the upper versus lower regions decreased (Figure 2, A and B; compare lanes 1 and 2), indicating NPR2 dephosphorylation in response to FGF and confirming, with primary chondrocytes, a previous study using a rat chondrosarcoma (RCS) cell line (26). This evidence concerns the gene NPR2 and chondrosarcoma.