PTBP1 knockdown decreases the sensitivity of SF-treated liver cancer cells to ferroptosis. PTBP1 (A) mRNA and (B) protein level changes following SF treatment (5 µM, 24 h). (C and D) SF inhibited the growth of liver cancer cells as revealed by the results of the CCK-8 assay. (E-G) Changes in the levels of ferroptosis indicators in liver cancer cells after SF treatment. Following silencing of PTBP1, the levels of (E) iron and (F) MDA significantly decreased, whereas that of (G) intracellular GSH significantly increased. (H) Representative confocal microscopic images of C11-BODIPY 581/591 staining in SF-treated liver cancer cells. *P<0.05, **P<0.01 and ***P<0.001 (Student's t-test). PTBP1, polypyrimidine tract-binding protein 1; SF, sorafenib; CCK-8, Cell Counting Kit-8; MDA, malondialdehyde; GSH, glutathione; NC, negative control; si-, small interfering RNA.