The inhibition of SMC growth by these pigments appears to involve the suppression of the rapidly accelerated fibrosarcoma (Raf)/extracellular-signal-regulated kinase (ERK)/MAPK signaling pathway, induction of p53 expression, hypophosphorylation of retinoblastoma protein, and the proteolysis of the transcription factor Yin Yang 1 (YY1), without any effect on ATP production or mitochondrial function [45,46,47,48]. Here, YY1 is linked to fibrosarcoma.