Jimenez et al. reported that PKC isoform δ (PKCδ) may play a crucial role in the upregulation of type I collagen expression in human fibroblasts cultures derived from skin samples of the patients with Ssc [53], whereas Conboy et al., and thereafter Wermuth et al., found CUR as a potent PKCδ inhibitor in vitro [54,55]. Here, PRKCD is linked to systemic sclerosis.