Compared with normal skin fibroblasts, there were more TUNEL staining-positive cells, higher RIPK1 and RIPK3 expressions as well as MLKL phosphorylation in keloid fibroblasts (P < 0.01), which were all reversed by NaHS pretreatment (P < 0.01) (Figure 8). Here, RIPK1 is linked to keloid.