PCNA and colorectal carcinoma: We observed that HSPB1 expression was positively correlated with the expression of ferroptosis suppressor genes, such as GPX4 (R = 0.53), FTH1 (R = 0.36) and PCNA (R = 0.11) but negatively correlated with the expression of ferroptosis driver genes, such as ACSL4 (R=-0.36) and TFRC (R=-0.32) (Fig. 8G), suggesting that HSPB1 overexpression suppresses CRC ferroptosis.