CCN2 and scleroderma: Others have shown that adenosine A2A receptor ligation increases collagen production and induces a pro-fibrotic phenotype in dermal fibroblasts isolated from scleroderma patients, in part by activation of the CB1 cannabinoid receptor [11].The present study strongly suggests, for the first time to our knowledge that an important mechanism for the adenosine-mediated promotion of fibrogenesis occurs at least in part through the regulation of the Ets factor, Fli1, and connective tissue growth factor (CTGF; CCN2).