In osteosarcoma, upregulation of ATF6 and E2F7 during sustained ERS suppressed E2F1 expression, upregulation of E2F7 was dependent on activation of XBP1, and downregulation of E2F1 enhanced Noxa and Puma expression and promoted ER stress-induced apoptosis [57]. This evidence concerns the gene E2F1 and osteosarcoma.