Ferroptosis, radiotherapy, and combination therapeutic strategies

Abstract

Ferroptosis, an iron-dependent form of regulated cell death driven by peroxidative damages of polyunsaturated-fatty-acid-containing phospholipids in cellular membranes, has recently been revealed to play an important role in radiotherapy-induced cell death and tumor suppression, and to mediate the synergy between radiotherapy and immunotherapy. In this review, we summarize known as well as putative mechanisms underlying the crosstalk between radiotherapy and ferroptosis, discuss the interactions between ferroptosis and other forms of regulated cell death induced by radiotherapy, and explore combination therapeutic strategies targeting ferroptosis in radiotherapy and immunotherapy. This review will provide important frameworks for future investigations of ferroptosis in cancer therapy.

Key words： ferroptosis; lipid peroxidation; GPX4; SLC7A11; radiotherapy; immunotherapy; radiosensitization; combination therapy

References

1 Adjemian S, Oltean T, Martens S, Wiernicki B, Goossens V, Berghe TV, Cappe B, Ladik M, Riquet FB, Heyndrickx L (2020) Ionizing radiation results in a mixture of cellular outcomes including mitotic catastrophe, senescence, methuosis, and iron-dependent cell death. Cell Death Dis 11:1–15

2 Alim I, Caulfield JT, Chen Y, Swarup V, Geschwind DH, Ivanova E, Seravalli J, Ai Y, Sansing LH, Marie EJS (2019) Selenium drives a transcriptional adaptive program to block ferroptosis and treat stroke. Cell 177(1262–1279):

3 Alvarez SW, Sviderskiy VO, Terzi EM, Papagiannakopoulos T, Moreira AL, Adams S, Sabatini DM, Birsoy K, Possemato R (2017) NFS1 undergoes positive selection in lung tumours and protects cells from ferroptosis. Nature 551:639–643

4 Anderson GJ, Vulpe CD (2009) Mammalian iron transport. Cell Mol Life Sci 66:3241

5 Angeli JPF, Conrad M (2018) Selenium and GPX4, a vital symbiosis. Free Radical Biol Med 127:153–159

6 Angeli JPF, Schneider M, Proneth B, Tyurina YY, Tyurin VA, Hammond VJ, Herbach N, Aichler M, Walch A, Eggenhofer E (2014) Inactivation of the ferroptosis regulator Gpx4 triggers acute renal failure in mice. Nat Cell Biol 16:1180–1191

7 Aubrey BJ, Kelly GL, Janic A, Herold MJ, Strasser A (2018) How does p53 induce apoptosis and how does this relate to p53-mediated tumour suppression? Cell Death Differ 25:104–113

8 Ayala A, Muñoz MF, Argüelles S (2014). Lipid peroxidation: production, metabolism, and signaling mechanisms of malondialdehyde and 4-hydroxy-2-nonenal. Oxid Med Cell Longevity

9 Azzam EI, Jay-Gerin J-P, Pain D (2012) Ionizing radiation-induced metabolic oxidative stress and prolonged cell injury. Cancer Lett 327:48–60

10 Badgley MA, Kremer DM, Maurer HC, DelGiorno KE, Lee H-J, Purohit V, Sagalovskiy IR, Ma A, Kapilian J, Firl CE (2020) Cysteine depletion induces pancreatic tumor ferroptosis in mice. Science 368:85–89

11 Baidoo KE, Yong K, Brechbiel MW (2013) Molecular pathways: targeted α-particle radiation therapy. Clin Cancer Res 19:530–537

12 Benveniste MF, Gomez D, Carter BW, Betancourt Cuellar SL, Shroff GS, Benveniste APA, Odisio EG, Marom EM (2019) Recognizing radiation therapy-related complications in the chest. Radiographics 39:344–366

13 Berbee M, Fu Q, Boerma M, Pathak R, Zhou D, Kumar KS, Hauer-Jensen M (2011) Reduction of radiation-induced vascular nitrosative stress by the vitamin E analog γ-tocotrienol: evidence of a role for tetrahydrobiopterin. Int J Radiat Oncol Biol Phys 79:884–891

14 Bersuker K, Hendricks J, Li Z, Magtanong L, Ford B, Tang PH, Roberts MA, Tong B, Maimone TJ, Zoncu R (2019) The CoQ oxidoreductase FSP1 acts parallel to GPX4 to inhibit ferroptosis. Nature 575:688

15 Bieging KT, Mello SS, Attardi LD (2014) Unravelling mechanisms of p53-mediated tumour suppression. Nat Rev Cancer 14:359–370

16 Boumahdi S, de Sauvage FJ (2020) The great escape: tumour cell plasticity in resistance to targeted therapy. Nat Rev Drug Discov 19:39–56

17 Braig M, Lee S, Loddenkemper C, Rudolph C, Peters AH, Schlegelberger B, Stein H, Dörken B, Jenuwein T, Schmitt CA (2005) Oncogene-induced senescence as an initial barrier in lymphoma development. Nature 436:660–665

18 Bristol ML, Di X, Beckman MJ, Wilson EN, Henderson SC, Maiti A, Fan Z, Gewirtz DA (2012) Dual functions of autophagy in the response of breast tumor cells to radiation: cytoprotective autophagy with radiation alone and cytotoxic autophagy in radiosensitization by vitamin D3. Autophagy 8:739–753

19 Brown CW, Amante JJ, Chhoy P, Elaimy AL, Liu H, Zhu LJ, Baer CE, Dixon SJ, Mercurio AM (2019) Prominin2 drives ferroptosis resistance by stimulating iron export. Dev Cell 51(575–586):

20 Bump EA, Brown JM (1990) Role of glutathione in the radiation response of mammalian cells invitro and in vivo. Pharmacol Ther 47:117–136

21 Cheema AK, Pathak R, Zandkarimi F, Kaur P, Alkhalil L, Singh R, Zhong X, Ghosh S, Aykin-Burns N, Hauer-Jensen M (2014) Liver metabolomics reveals increased oxidative stress and fibrogenic potential in gfrp transgenic mice in response to ionizing radiation. J Proteome Res 13:3065–3074

22 Chen C-Y, Oliner JD, Zhan Q, Fornace AJ, Vogelstein B, Kastan MB (1994) Interactions between p53 and MDM2 in a mammalian cell cycle checkpoint pathway. Proc Natl Acad Sci 91:2684–2688

23 Chen D, Fan Z, Rauh M, Buchfelder M, Eyupoglu I, Savaskan N (2017a) ATF4 promotes angiogenesis and neuronal cell death and confers ferroptosis in a xCT-dependent manner. Oncogene 36:5593–5608

24 Chen D, Tavana O, Chu B, Erber L, Chen Y, Baer R, Gu W (2017b) NRF2 is a major target of ARF in p53-independent tumor suppression. Mol Cell 68(224–232):

25 Chen P-H, Wu J, Ding C-KC, Lin C-C, Pan S, Bossa N, Xu Y, Yang W-H, Mathey-Prevot B, Chi J-T (2020) Kinome screen of ferroptosis reveals a novel role of ATM in regulating iron metabolism. Cell Death Differ 27:1008–1022

26 Chew SH, Okazaki Y, Akatsuka S, Wang S, Jiang L, Ohara Y, Ito F, Saya H, Sekido Y, Toyokuni S (2017) Rheostatic CD44 isoform expression and its association with oxidative stress in human malignant mesothelioma. Free Radical Biol Med 106:91–99

27 Chio IIC, Tuveson DA (2017) ROS in cancer: the burning question. Trends Mol Med 23:411–429

28 Choudhary S, Burns SC, Mirsafian H, Li W, Vo DT, Qiao M, Lei X, Smith AD, Penalva LO (2020) Genomic analyses of early responses to radiation inglioblastoma reveal new alterations at transcription, splicing, and translation levels. Sci Rep 10:1–12

29 Chu B, Kon N, Chen D, Li T, Liu T, Jiang L, Song S, Tavana O, Gu W (2019) ALOX12 is required for p53-mediated tumour suppression through a distinct ferroptosis pathway. Nat Cell Biol 21:579–591

30 Colles SM, Chisolm GM (2000) Lysophosphatidylcholine-induced cellular injury in cultured fibroblasts involves oxidative events. J Lipid Res 41:1188–1198

31 Conrad M, Pratt DA (2019) The chemical basis of ferroptosis. Nat Chem Biol 15:1137–1147

32 Conrad M, Proneth B (2020) Selenium: tracing another essential element of ferroptotic cell death. Cell Chem Biol

33 Conrad M, Sato H (2012) The oxidative stress-inducible cystine/glutamate antiporter, system x c−: cystine supplier and beyond. Amino Acids 42:231–246

34 Crabtree MJ, Tatham AL, Hale AB, Alp NJ, Channon KM (2009) Critical role for tetrahydrobiopterin recycling by dihydrofolate reductase in regulation of endothelial nitric-oxide synthase coupling relative importance of the de novo biopterin synthesis versus salvage pathways. J Biol Chem 284:28128–28136

35 de la Vega MR, Chapman E, Zhang DD (2018) NRF2 and the hallmarks of cancer. Cancer Cell 34:21–43

36 Delaney G, Jacob S, Featherstone C, Barton M (2005) The role of radiotherapy in cancer treatment: estimating optimal utilization from a review of evidence-based clinical guidelines. Cancer 104:1129–1137

37 Dixon SJ, Lemberg KM, Lamprecht MR, Skouta R, Zaitsev EM, Gleason CE, Patel DN, Bauer AJ, Cantley AM, Yang WS (2012) Ferroptosis: an iron-dependent form of nonapoptotic cell death. Cell 149:1060–1072

38 Dixon SJ, Patel DN, Welsch M, Skouta R, Lee ED, Hayano M, Thomas AG, Gleason CE, Tatonetti NP, Slusher BS (2014) Pharmacological inhibition of cystine–glutamate exchange induces endoplasmic reticulum stress and ferroptosis. Elife 3:

39 Dixon SJ, Winter GE, Musavi LS, Lee ED, Snijder B, Rebsamen M, Superti-Furga G, Stockwell BR (2015) Human haploid cell genetics reveals roles for lipid metabolism genes in nonapoptotic cell death. ACS Chem Biol 10:1604–1609

40 Doll S, Proneth B, Tyurina YY, Panzilius E, Kobayashi S, Ingold I, Irmler M, Beckers J, Aichler M, Walch A (2017) ACSL4 dictates ferroptosis sensitivity by shaping cellular lipid composition. Nat Chem Biol 13:91–98

41 Doll S, Freitas FP, Shah R, Aldrovandi M, da Silva MC, Ingold I, Grocin AG, da Silva TNX, Panzilius E, Scheel C (2019) FSP1 is a glutathione-independent ferroptosis suppressor. Nature. 575:693

42 Duberley K, Heales S, Abramov A, Chalasani A, Land J, Rahman S, Hargreaves I (2014) Effect of Coenzyme Q10 supplementation on mitochondrial electron transport chain activity and mitochondrial oxidative stress in Coenzyme Q10 deficient human neuronal cells. Int J Biochem Cell Biol 50:60–63

43 Elguindy MM, Nakamaru-Ogiso E (2015) Apoptosis-inducing factor (AIF) and its family member protein, AMID, are rotenonesensitive NADH: ubiquinone oxidoreductases (NDH-2). J Biol Chem 290:20815–20826

44 Fan Z, Wirth A, Chen D, Wruck C, Rauh M, Buchfelder M, Savaskan N (2017) Nrf2-Keap1 pathway promotes cell proliferation and diminishes ferroptosis. Oncogenesis 6:e371–e371

45 Fei P, El-Deiry WS (2003) P53 and radiation responses. Oncogene 22:5774–5783

46 Feng H, Schorpp K, Jin J, Yozwiak CE, Hoffstrom BG, Decker AM, Rajbhandari P, Stokes ME, Bender HG, Csuka JM (2020) Transferrin receptor is a specific ferroptosis marker. Cell Rep 30(3411–3423):

47 Frei B, Kim MC, Ames BN (1990) Ubiquinol-10 is an effective lipidsoluble antioxidant at physiological concentrations. Proc Natl Acad Sci 87:4879–4883

48 Galluzzi L, Vitale I, Aaronson SA, Abrams JM, Adam D, Agostinis P, Alnemri ES, Altucci L, Amelio I, Andrews DW (2018) Molecular mechanisms of cell death: recommendations of the Nomenclature Committee on Cell Death 2018. Cell Death Differ 25:486–541

49 Gao M, Monian P, Quadri N, Ramasamy R, Jiang X (2015) Glutaminolysis and transferrin regulate ferroptosis. Mol Cell 59:298–308

50 Gao M, Monian P, Pan Q, Zhang W, Xiang J, Jiang X (2016) Ferroptosis is an autophagic cell death process. Cell Res 26:1021–1032

51 Garcia-Bermudez J, Baudrier L, Bayraktar EC, Shen Y, La K, Guarecuco R, Yucel B, Fiore D, Tavora B, Freinkman E (2019) Squalene accumulation in cholesterol auxotrophic lymphomas prevents oxidative cell death. Nature 567:118–122

52 Geng N, Shi B, Li S, Zhong Z, Li Y, Xua W, Zhou H, Cai J (2018) Knockdown of ferroportin accelerates erastin-induced ferroptosis in neuroblastoma cells. Eur Rev Med Pharmacol Sci 22:3826–3836

53 Georgakilas AG, Martin OA, Bonner WM (2017) p21: a two-faced genome guardian. Trends Mol Med 23:310–319

54 Green DR (2019) The coming decade of cell death research: five riddles. Cell 177:1094–1107

55 Gudkov AV, Komarova EA (2003) The role of p53 in determining sensitivity to radiotherapy. Nat Rev Cancer 3:117–129

56 Guo J, Xu B, Han Q, Zhou H, Xia Y, Gong C, Dai X, Li Z, Wu G(2018) Ferroptosis: a novel anti-tumor action for cisplatin. Cancer Res Treat 50:445

57 Habib E, Linher-Melville K, Lin H-X, Singh G (2015) Expression of xCT and activity of system xc− are regulated by NRF2 in human breast cancer cells in response to oxidative stress. Redox Biol 5:33–42

58 Han Y, Platonov A, Akhalaia M, Yun Y-S, Song J-Y (2005) Differential effect of γ-radiation-induced heme oxygenase-1 activity in female and male C57BL/6 mice. J Korean Med Sci 20:535–541

59 Hanahan D, Weinberg RA (2011) Hallmarks of cancer: the next generation. Cell 144:646–674

60 Hangauer MJ, Viswanathan VS, Ryan MJ, Bole D, Eaton JK, Matov A, Galeas J, Dhruv HD, Berens ME, Schreiber SL (2017) Drugtolerant persister cancer cells are vulnerable to GPX4 inhibition. Nature 551:247–250

61 Hassannia B, Wiernicki B, Ingold I, Qu F, Van Herck S, Tyurina YY, Bayır H, Abhari BA, Angeli JPF, Choi SM (2018) Nano-targeted induction of dual ferroptotic mechanisms eradicates high-risk neuroblastoma. J Clin Investig 128:3341–3355

62 Hassannia B, Vandenabeele P, Berghe TV (2019) Targeting ferroptosis to iron out cancer. Cancer Cell 35:830–849

63 Hayano M, Yang W, Corn C, Pagano N, Stockwell B (2016) Loss of cysteinyl-tRNA synthetase (CARS) induces the transsulfuration pathway and inhibits ferroptosis induced by cystine deprivation. Cell Death Differ 23:270–278

64 Herrera FG, Bourhis J, Coukos G (2017) Radiotherapy combination opportunities leveraging immunity for the next oncology practice. Cancer J Clin 67:65–85

65 Horikoshi N, Cong J, Kley N, Shenk T (1999) Isolation of differentially expressed cDNAs from p53-dependent apoptotic cells: activation of the human homologue of the Drosophila peroxidasin gene. Biochem Biophys Res Commun 261:864–869

66 Hou W, Xie Y, Song X, Sun X, Lotze MT, Zeh HJ III, Kang R, Tang D (2016) Autophagy promotes ferroptosis by degradation of ferritin. Autophagy 12:1425–1428

67 Hu W, Zhang C, Wu R, Sun Y, Levine A, Feng Z (2010) Glutaminase 2, a novel p53 target gene regulating energy metabolism and antioxidant function. Proc Natl Acad Sci 107:7455–7460

68 Hu L, Wang H, Huang L, Zhao Y, Wang J (2016) Crosstalk between autophagy and intracellular radiation response. Int J Oncol 49:2217–2226

69 Hu K, Li K, Lv J, Feng J, Chen J, Wu H, Cheng F, Jiang W, Wang J, Pei H (2020) Suppression of the SLC7A11/glutathione axis causes synthetic lethality in KRAS-mutant lung adenocarcinoma. J Clin Invest 130:1752

70 Huang R-X, Zhou P-K (2020) DNA damage response signaling pathways and targets for radiotherapy sensitization in cancer. Signal Transd Target Therapy 5:1–27

71 Hwang PM, Bunz F, Yu J, Rago C, Chan TA, Murphy MP, Kelso GF, Smith RA, Kinzler KW, Vogelstein B (2001) Ferredoxin reductase affects p53-dependent, 5-fluorouracil-induced apoptosis in colorectal cancer cells. Nat Med 7:1111–1117

72 Ingold I, Berndt C, Schmitt S, Doll S, Poschmann G, Buday K, Roveri A, Peng X, Freitas FP, Seibt T (2018) Selenium utilization by GPX4 is required to prevent hydroperoxide-induced ferroptosis. Cell 172(409–422):

73 Ishimoto T, Nagano O, Yae T, Tamada M, Motohara T, Oshima H, Oshima M, Ikeda T, Asaba R, Yagi H (2011) CD44 variant regulates redox status in cancer cells by stabilizing the xCT subunit of system xc− and thereby promotes tumor growth. Cancer Cell 19:387–400

74 Jaffray DA (2012) Image-guided radiotherapy: from current concept to future perspectives. Nat Rev Clin Oncol 9:688

75 Jiang L, Kon N, Li T, Wang S-J, Su T, Hibshoosh H, Baer R, Gu W (2015) Ferroptosis as a p53-mediated activity during tumour suppression. Nature 520:57–62

76 Kagan VE, Mao G, Qu F, Angeli JPF, Doll S, St Croix C, Dar HH, Liu B, Tyurin VA, Ritov VB (2017) Oxidized arachidonic and adrenic PEs navigate cells to ferroptosis. Nat Chem Biol 13:81–90

77 Kaku Y, Tsuchiya A, Kanno T, Nishizaki T (2015) HUHS1015 induces necroptosis and caspase-independent apoptosis of MKN28human gastric cancer cells in association with AMID accumulation in the nucleus. Anti-Cancer Agents Med Chem 15:242–247

78 Kam WW-Y, Banati RB (2013) Effects of ionizing radiation on mitochondria. Free Radical Biol Med 65:607–619

79 Kang R, Tang D (2016) What is the pathobiology of inflammation to cell death? Apoptosis, necrosis, necroptosis, autophagic cell death, pyroptosis, and NETosis. In: Autophagy networks in inflammation. Springer, Berlin, pp 81–106

80 Kang R, Kroemer G, Tang D (2019) The tumor suppressor protein p53 and the ferroptosis network. Free Radical Biol Med 133:162–168

81 Kim SE, Zhang L, Ma K, Riegman M, Chen F, Ingold I, Conrad M, Turker MZ, Gao M, Jiang X (2016) Ultrasmall nanoparticles induce ferroptosis in nutrient-deprived cancer cells and suppress tumour growth. Nat Nanotechnol 11:977

82 Koppula P, Zhang Y, Zhuang L, Gan B (2018) Amino acid transporter SLC7A11/xCT at the crossroads of regulating redox homeostasis and nutrient dependency of cancer. Cancer Commun 38:1–13

83 Koppula P, Zhuang L, Gan B (2020) Cystine transporter SLC7A11/xCT in cancer: ferroptosis, nutrient dependency, and cancer therapy. Protein Cell.https://doi.org/10.1007/s13238-020-00789-5

84 Kordbacheh T, Honeychurch J, Blackhall F, Faivre-Finn C, Illidge T (2018) Radiotherapy and anti-PD-1/PD-L1 combinations in lung cancer: building better translational research platforms. Ann Oncol 29:301–310

85 Kraft VA, Bezjian CT, Pfeiffer S, Ringelstetter L, Müller C, Zandkarimi F, Merl-Pham J, Bao X, Anastasov N, Kössl J (2019) GTP cyclohydrolase 1/tetrahydrobiopterin counteract ferroptosis through lipid remodeling. ACS Central Sci 6:41–53

86 Lang X, Green MD, Wang W, Yu J, Choi JE, Jiang L, Liao P, Zhou J, Zhang Q, Dow A (2019) Radiotherapy and immunotherapy promote tumoral lipid oxidation and ferroptosis via synergistic repression of SLC7A11. Cancer Discov 9:1673–1685

87 Leach JK, Van Tuyle G, Lin P-S, Schmidt-Ullrich R, Mikkelsen RB (2001) Ionizing radiation-induced, mitochondria-dependent generation of reactive oxygen/nitrogen. Cancer Res 61:3894–3901

88 Lee H, Zandkarimi F, Zhang Y, Meena JK, Kim J, Zhuang L, Tyagi S, Ma L, Westbrook TF, Steinberg GR (2020) Energy-stressmediated AMPK activation inhibits ferroptosis. Nat Cell Biol 22:225–234

89 Lei G, Zhang Y, Koppula P, Liu X, Zhang J, Lin SH, Ajani JA, Xiao Q, Liao Z, Wang H (2020) The role of ferroptosis in ionizing radiation-induced cell death and tumor suppression. Cell Res 30:146–162

90 Li L, Rezvan A, Salerno JC, Husain A, Kwon K, Jo H, Harrison DG, Chen W (2010) GTP cyclohydrolase I phosphorylation and interaction with GTP cyclohydrolase feedback regulatory protein provide novel regulation of endothelial tetrahydrobiopterin and nitric oxide. Circ Res 106:328–336

91 Li M, You L, Xue J, Lu Y (2018) Ionizing radiation-induced cellular senescence in normal, non-transformed cells and the involved DNA damage response: a mini review. Front Pharmacol 9:522

92 Li X, Duan L, Yuan S, Zhuang X, Qiao T, He J (2019a) Ferroptosis inhibitor alleviates radiation-induced lung fibrosis (RILF) via down-regulation of TGF-β1. J Inflamm 16:11

93 Li X, Zhuang X, Qiao T (2019b) Role of ferroptosis in the process of acute radiation-induced lung injury in mice. Biochem Biophys Res Commun 519:240–245

94 Li C, Dong X, Du W, Shi X, Chen K, Zhang W, Gao M (2020) LKB1-AMPK axis negatively regulates ferroptosis by inhibiting fatty acid synthesis. Signal Transd Target Ther 5:1–4

95 Liang C, Zhang X, Yang M, Dong X (2019) Recent progress in ferroptosis inducers for cancer therapy. Adv Mater 31:1904197

96 Liu B, Yi J, Yang X, Liu L, Lou X, Zhang Z, Qi H, Wang Z, Zou J, Zhu W-G (2019a) MDM2-mediated degradation of WRN promotes cellular senescence in a p53-independent manner. Oncogene 38:2501–2515

97 Liu T, Jiang L, Tavana O, Gu W (2019b) The deubiquitylase OTUB1 mediates ferroptosis via stabilization of SLC7A11. Cancer Res 79:1913–1924

98 Liu J, Kuang F, Kroemer G, Klionsky DJ, Kang R, Tang D (2020a) Autophagy-dependent ferroptosis: machinery and regulation. Cell Chem Biol 27:420

99 Liu J, Zhu Z, Liu Y, Wei L, Li B, Mao F, Zhang J, Wang Y, Liu Y (2020b) MDM2 inhibition-mediated autophagy contributes to the pro-apoptotic effect of berberine in p53-null leukemic cells. Life Sci 242:

100 Liu X, Olszewski K, Zhang Y, Lim EW, Shi J, Zhang X, Zhang J, Lee H, Koppula P, Lei G (2020c) Cystine transporter regulation of pentose phosphate pathway dependency and disulfide stress exposes a targetable metabolic vulnerability in cancer. Nat Cell Biol 22:476–486

101 Liu X, Zhang Y, Zhuang L, Olszewski K, Gan B (2020d) NADPH debt drives redox bankruptcy: SLC7A11/xCT-mediated cystine uptake as a double-edge sword in cellular redox regulation. Genes Dis. https://doi.org/10.1016/j.gendis.2020.11.010

102 Louandre C, Marcq I, Bouhlal H, Lachaier E, Godin C, Saidak Z, François C, Chatelain D, Debuysscher V, Barbare J-C (2015) The retinoblastoma (Rb) protein regulates ferroptosis induced by sorafenib in human hepatocellular carcinoma cells. Cancer Lett 356:971–977

103 Ma S, Henson E, Chen Y, Gibson S (2016) Ferroptosis is induced following siramesine and lapatinib treatment of breast cancer cells. Cell Death Dis 7:e2307–e2307

104 Magtanong L, Ko P-J, To M, Cao JY, Forcina GC, Tarangelo A, Ward CC, Cho K, Patti GJ, Nomura DK (2019) Exogenous monounsaturated fatty acids promote a ferroptosis-resistant cell state. Cell Chem Biol 26(420–432):

105 Maier P, Hartmann L, Wenz F, Herskind C (2016) Cellular pathways in response to ionizing radiation and their targetability for tumor radiosensitization. Int J Mol Sci 17:102

106 Malhotra J, Jabbour SK, Aisner J (2017) Current state of immunotherapy for non-small cell lung cancer. Transl Lung Cancer Res 6:196

107 Marshall KR, Gong M, Wodke L, Lamb JH, Jones DJ, Farmer PB, Scrutton NS, Munro AW (2005) The human apoptosis-inducing protein AMID is an oxidoreductase with a modified flavin cofactor and DNA binding activity. J Biol Chem 280:30735–30740

108 Maya R, Balass M, Kim S-T, Shkedy D, Leal J-FM, Shifman O, Moas M, Buschmann T, Ronai ZE, Shiloh Y (2001) ATM-dependent phosphorylation of Mdm2 on serine 395: role in p53 activation by DNA damage. Genes Dev 15:1067–1077

109 McCullagh EA, Featherstone DE (2014) Behavioral characterization of system xc-mutant mice. Behav Brain Res 265:1–11

110 McDonald JT, Kim K, Norris AJ, Vlashi E, Phillips TM, Lagadec C, Della Donna L, Ratikan J, Szelag H, Hlatky L (2010) Ionizing radiation activates the Nrf2 antioxidant response. Cancer Res 70:8886–8895

111 Mijit M, Caracciolo V, Melillo A, Amicarelli F, Giordano A (2020) Role of p53 in the regulation of cellular senescence. Biomolecules 10:420

112 Mohamad O, Tabuchi T, Nitta Y, Nomoto A, Sato A, Kasuya G, Makishima H, Choy H, Yamada S, Morishima T (2019) Risk of subsequent primary cancers after carbon ion radiotherapy, photon radiotherapy, or surgery for localised prostate cancer: a propensity score-weighted, retrospective, cohort study. Lancet Oncol 20:674–685

113 Mohan R, Grosshans D (2017) Proton therapy: present and future. Adv Drug Deliv Rev 109:26–44

114 Mumbauer S, Pascual J, Kolotuev I, Hamaratoglu F (2019) Ferritin heavy chain protects the developing wing from reactive oxygen species and ferroptosis. PLoS Genet 15:

115 Nehs MA, Lin C-I, Kozono DE, Whang EE, Cho NL, Zhu K, Moalem J, Moore FD Jr, Ruan DT (2011) Necroptosis is a novel mechanism of radiation-induced cell death in anaplastic thyroid and adrenocortical cancers. Surgery 150:1032–1039

116 Nguyen HP, Yi D, Lin F, Viscarra JA, Tabuchi C, Ngo K, Shin G (2020) Aifm2, a NADH oxidase, supports robust glycolysis and is required for cold-and diet-induced thermogenesis. Mol Cell 77 (600–617):

117 Ohiro Y, Garkavtsev I, Kobayashi S, Sreekumar KR, Nantz R, Higashikubo BT, Duffy SL, Higashikubo R, Usheva A, Gius D (2002) A novel p53-inducible apoptogenic gene, PRG3, encodes a homologue of the apoptosis-inducing factor (AIF). FEBS Lett 524:163–171

118 Ou Y, Wang S-J, Li D, Chu B, Gu W (2016) Activation of SAT1 engages polyamine metabolism with p53-mediated ferroptotic responses. Proc Natl Acad Sci 113:E6806–E6812

119 Padanad MS, Konstantinidou G, Venkateswaran N, Melegari M, Rindhe S, Mitsche M, Yang C, Batten K, Huffman KE, Liu J (2016) Fatty acid oxidation mediated by Acyl-CoA synthetase long chain 3 is required for mutant KRAS lung tumorigenesis. Cell Rep 16:1614–1628

120 Pan X, Lin Z, Jiang D, Yu Y, Yang D, Zhou H, Zhan D, Liu S, Peng G, Chen Z (2019) Erastin decreases radioresistance of NSCLC cells partially by inducing GPX4-mediated ferroptosis. Oncol Lett 17:3001–3008

121 Pang M, Liu X, Slagle-Webb B, Madhankumar A, Connor J (2016) Role of h-ferritin in radiosensitivity of human gliomacells. J Cancer Biol Treat 3:1–10

122 Pathak R, Pawar SA, Fu Q, Gupta PK, Berbée M, Garg S, Sridharan V, Wang W, Biju PG, Krager KJ (2014) Characterization of transgenic Gfrp knock-in mice: implications for tetrahydrobiopterin in modulation of normal tissue radiation responses. Antioxid Redox Signal 20:1436–1446

123 Paton CM, Ntambi JM (2009) Biochemical and physiological function of stearoyl-CoA desaturase. Am J Physiol Endocrinol Metab 297: E28–E37

124 Ran Q, Liang H, Ikeno Y, Qi W, Prolla TA, Roberts LJ, Wolf N, VanRemmen H, Richardson A (2007) Reduction in glutathione peroxidase 4 increases life span through increased sensitivity to apoptosis. J Gerontol A 62:932–942

125 Rao SG, Jackson JG (2016) SASP: tumor suppressor or promoter? Yes! Trends Cancer 2:676–687

126 Reisz JA, Bansal N, Qian J, Zhao W, Furdui CM (2014) Effects of ionizing radiation on biological molecules—mechanisms of damage and emerging methods of detection. Antioxid Redox Signal 21:260–292

127 Sabin RJ, Anderson RM (2011) Cellular Senescence-its role in cancer and the response to ionizing radiation. Genome Integrity 2:7

128 Sanli T, Rashid A, Liu C, Harding S, Bristow RG, Cutz J-C, Singh G, Wright J, Tsakiridis T (2010) Ionizing radiation activates AMPactivated kinase (AMPK): a target for radiosensitization of human cancer cells. Int J Radiat Oncol Biol Phys 78:221–229

129 Sanli T, Steinberg GR, Singh G, Tsakiridis T (2014) AMP-activated protein kinase (AMPK) beyond metabolism: a novel genomic stress sensor participating in the DNA damage response pathway. Cancer Biol Ther 15:156–169

130 Sato H, Tamba M, Ishii T, Bannai S (1999) Cloning and expression of a plasma membrane cystine/glutamate exchange transporter composed of two distinct proteins. J Biol Chem 274:11455–11458

131 Sato H, Shiiya A, Kimata M, Maebara K, Tamba M, Sakakura Y, Makino N, Sugiyama F, Yagami K-I, Moriguchi T (2005) Redox imbalance in cystine/glutamate transporter-deficient mice. J Biol Chem 280:37423–37429

132 Shadyro O, Yurkova I, Kisel M (2002) Radiation-induced peroxidation and fragmentation of lipids in a model membrane. Int J Radiat Biol 78:211–217

133 Shah R, Shchepinov MS, Pratt DA (2018) Resolving the role of lipoxygenases in the initiation and execution of ferroptosis. ACS Central Sci 4:387–396

134 Sheikh M, Fornace AJ (2000) Death and decoy receptors and p53-mediated apoptosis. Leukemia 14:1509–1513

135 Shimada K, Skouta R, Kaplan A, Yang WS, Hayano M, Dixon SJ, Brown LM, Valenzuela CA, Wolpaw AJ, Stockwell BR (2016) Global survey of cell death mechanisms reveals metabolic regulation of ferroptosis. Nat Chem Biol 12:497–503

136 Singhal R, Mitta SR, Olive KP, Lyssiotis CA, Shah YM (2019) Hypoxia inducible factor-2α increases sensitivity of colon cancer cells towards oxidative cell death. BioRxiv, 823997

137 Song YP, Colaco RJ (2018) Radiation necrosis-a growing problem in a case of brain metastases following whole brain radiotherapy and stereotactic radiosurgery. Cureus 10

138 Song X, Zhu S, Chen P, Hou W, Wen Q, Liu J, Xie Y, Liu J, Klionsky DJ, Kroemer G (2018) AMPK-mediated BECN1 phosphorylation promotes ferroptosis by directly blocking system Xc-activity. Curr Biol 28(2388–2399):

139 Soula M, Weber RA, Zilka O, Alwaseem H, La K, Yen F, Molina H, Garcia-Bermudez J, Pratt DA, Birsoy K (2020) Metabolic determinants of cancer cell sensitivity to canonical ferroptosis inducers. Nat Chem Biol 16:1351–1360

140 Stockwell BR, Angeli JPF, Bayir H, Bush AI, Conrad M, Dixon SJ, Fulda S, Gascón S, Hatzios SK, Kagan VE (2017) Ferroptosis: a regulated cell death nexus linking metabolism, redox biology, and disease. Cell 171:273–285

141 Stockwell BR, Jiang X, Gu W (2020) Emerging mechanisms and disease relevance of ferroptosis. Trends Cell Biol

142 Sun X, Niu X, Chen R, He W, Chen D, Kang R, Tang D (2016) Metallothionein-1G facilitates sorafenib resistance through inhibition of ferroptosis. Hepatology 64:488–500

143 Suzuki S, Tanaka T, Poyurovsky MV, Nagano H, Mayama T, Ohkubo S, Lokshin M, Hosokawa H, Nakayama T, Suzuki Y (2010) Phosphate-activated glutaminase (GLS2), a p53-inducible regulator of glutamine metabolism and reactive oxygen species. Proc Natl Acad Sci 107:7461–7466

144 Tarangelo A, Magtanong L, Bieging-Rolett KT, Li Y, Ye J, Attardi LD, Dixon SJ (2018) p53 suppresses metabolic stress-induced ferroptosis in cancer cells. Cell Rep 22:569–575

145 Tesfay L, Paul BT, Konstorum A, Deng Z, Cox AO, Lee J, Furdui CM, Hegde P, Torti FM, Torti SV (2019) Stearoyl-coa desaturase 1protects ovarian cancer cells from ferroptotic cell death. Cancer Res 79:5355–5366

146 Thariat J, Hannoun-Levi J-M, Myint AS, Vuong T, Gérard J-P (2013) Past, present, and future of radiotherapy for the benefit of patients. Nat Rev Clin Oncol 10:52

147 Tsoi J, Robert L, Paraiso K, Galvan C, Sheu KM, Lay J, Wong DJ, Atefi M, Shirazi R, Wang X (2018) Multi-stage differentiation defines melanoma subtypes with differential vulnerability to druginduced iron-dependent oxidative stress. Cancer Cell 33(890–904):

148 Vakifahmetoglu H, Olsson M, Zhivotovsky B (2008) Death through a tragedy: mitotic catastrophe. Cell Death Differ 15:1153–1162

149 Vařecha M, Amrichová J, Zimmermann M, Ulman V, Lukášová E, Kozubek M (2007) Bioinformatic and image analyses of the cellular localization of the apoptotic proteins endonuclease G, AIF, and AMID during apoptosis in human cells. Apoptosis 12:1155–1171

150 Venkatesh D, O’Brien NA, Zandkarimi F, Tong DR, Stokes ME, Dunn DE, Kengmana ES, Aron AT, Klein AM, Csuka JM (2020) MDM2 and MDMX promote ferroptosis by PPARα-mediated lipid remodeling. Genes Dev 34:526–543

151 Viswanathan VS, Ryan MJ, Dhruv HD, Gill S, Eichhoff OM, Seashore-Ludlow B, Kaffenberger SD, Eaton JK, Shimada K, Aguirre AJ (2017) Dependency of a therapy-resistant state of cancer cells on a lipid peroxidase pathway. Nature 547:453–457

152 Vousden KH (2000) p53: death star. Cell 103:691–694

153 Walden T, Hughes H (1988) SpringerLink (Online service). Prostaglandin and lipid metabolism in radiation injury. Springer, Boston

154 Wang L, Cai H, Hu Y, Liu F, Huang S, Zhou Y, Yu J, Xu J, Wu F (2018) A pharmacological probe identifies cystathionine β-synthase as a new negative regulator for ferroptosis. Cell Death Dis 9:1–17

155 Wang H, Jiang H, Van De Gucht M, De Ridder M (2019a) Hypoxic radioresistance: can ROS be the key to overcome it? Cancers 11:112

156 Wang W, Green M, Choi JE, Gijón M, Kennedy PD, Johnson JK, Liao P, Lang X, Kryczek I, Sell A (2019b) CD8+ T cells regulate tumour ferroptosis during cancer immunotherapy. Nature 569:270–274

157 Wang Y, Yang L, Zhang X, Cui W, Liu Y, Sun QR, He Q, Zhao S, Zhang GA, Wang Y (2019c) Epigenetic regulation of ferroptosis by H2B monoubiquitination and p53. EMBO Rep 20:

158 Wang L, Liu Y, Du T, Yang H, Lei L, Guo M, Ding H-F, Zhang J, Wang H, Chen X (2020) ATF3 promotes erastin-induced ferroptosis by suppressing system Xc–. Cell Death Differ 27:662–675

159 Wenzel SE, Tyurina YY, Zhao J, Croix CMS, Dar HH, Mao G, Tyurin VA, Anthonymuthu TS, Kapralov AA, Amoscato AA (2017) PEBP1 wardens ferroptosis by enabling lipoxygenase generation of lipid death signals. Cell 171(628–641):

160 Williams MV, James ND, Summers E, Barrett A, Ash DV, Sub-Committee A (2006) National survey of radiotherapy fractionation practice in 2003. Clin Oncol 18:3–14

161 Withers HR (1985) Biologic basis for altered fractionation schemes. Cancer 55:2086–2095

162 Wolszczak M, Gajda J (2010) Iron release from ferritin induced by light and ionizing radiation. Res Chem Intermed 36:549–563

163 Woo JH, Shimoni Y, Yang WS, Subramaniam P, Iyer A, Nicoletti P, Martínez MR, López G, Mattioli M, Realubit R (2015) Elucidating compound mechanism of action by network perturbation analysis. Cell 162:441–451

164 Wu D, Prives C (2018) Relevance of the p53–MDM2 axis to aging. Cell Death Differ 25:169–179

165 Wu M, Xu L-G, Li X, Zhai Z, Shu H-B (2002) AMID, an apoptosisinducing factor-homologous mitochondrion-associated protein, induces caspase-independent apoptosis. J Biol Chem 277:25617–25623

166 Wu M, Xu L-G, Su T, Tian Y, Zhai Z, Shu H-B (2004) AMID is a p53-inducible gene downregulated in tumors. Oncogene 23:6815–6819

167 Xie L, Song X, Yu J, Guo W, Wei L, Liu Y, Wang X (2011) Solute carrier protein family may involve in radiation-induced radioresistance of non-small cell lung cancer. J Cancer Res Clin Oncol 137:1739

168 Xie Y, Zhu S, Song X, Sun X, Fan Y, Liu J, Zhong M, Yuan H, Zhang L, Billiar TR (2017) The tumor suppressor p53 limits ferroptosis by blocking DPP4 activity. Cell Rep 20:1692–1704

169 Yan B, Ai Y, Sun Q, Ma Y, Cao Y, Wang J, Zhang Z, Wang X (2020) Membrane damage during ferroptosis is caused by oxidation of phospholipids catalyzed by the oxidoreductases POR and CYB5R1. Mol Cell

170 Yang D, Yaguchi T, Nagata T, Gotoh A, Dovat S, Song C, Nishizaki T (2011) AMID mediates adenosine-induced caspase-independent HuH-7 cell apoptosis. Cell Physiol Biochem 27:37–44

171 Yang WS, SriRamaratnam R, Welsch ME, Shimada K, Skouta R, Viswanathan VS, Cheah JH, Clemons PA, Shamji AF, Clish CB (2014) Regulation of ferroptotic cancer cell death by GPX4. Cell 156:317–331

172 Yang WS, Kim KJ, Gaschler MM, Patel M, Shchepinov MS, Stockwell BR (2016) Peroxidation of polyunsaturated fatty acids by lipoxygenases drives ferroptosis. Proc Natl Acad Sci 113: E4966–E4975

173 Ye LF, Chaudhary KR, Zandkarimi F, Harken AD, Kinslow CJ, Upadhyayula PS, Dovas A, Higgins DM, Tan H, Zhang Y (2020) Radiation-induced lipid peroxidation triggers ferroptosis and synergizes with ferroptosis inducers. ACS Chem Biol 15:469–484

174 Yi J, Zhu J, Wu J, Thompson CB, Jiang X (2020) Oncogenic activation of PI3K-AKT-mTOR signaling suppresses ferroptosis via SREBP-mediated lipogenesis. Proc Natl Acad Sci 117:31189–31197

175 Yoo S-E, Chen L, Na R, Liu Y, Rios C, Van Remmen H, Richardson A, Ran Q (2012) Gpx4 ablation in adult mice results in a lethal phenotype accompanied by neuronal loss in brain. Free Radical Biol Med 52:1820–1827

176 Zhang D, Wang W, Sun X, Xu D, Wang C, Zhang Q, Wang H, Luo W, Chen Y, Chen H (2016) AMPK regulates autophagy by phosphorylating BECN1 at threonine 388. Autophagy 12:1447–1459

177 Zhang Y, Qian Y, Zhang J, Yan W, Jung Y-S, Chen M, Huang E, Lloyd K, Duan Y, Wang J (2017) Ferredoxin reductase is critical for p53-dependent tumor suppression via iron regulatory protein 2. Genes Dev 31:1243–1256

178 Zhang Y, Shi J, Liu X, Feng L, Gong Z, Koppula P, Sirohi K, Li X, Wei Y, Lee H (2018) BAP1 links metabolic regulation of ferroptosis to tumour suppression. Nat Cell Biol 20:1181–1192

179 Zhang Y, Tan H, Daniels JD, Zandkarimi F, Liu H, Brown LM, Uchida K, O’Connor OA, Stockwell BR (2019a) Imidazole ketone erastin induces ferroptosis and slows tumor growth in a mouse lymphoma model. Cell Chem Biol 26(623–633):

180 Zhang Y, Zhuang L, Gan B (2019b) BAP1 suppresses tumor development by inducing ferroptosis upon SLC7A11 repression. Mol Cell Oncol 6:1536845

181 Zhang X, Sui S, Wang L, Li H, Zhang L, Xu S, Zheng X (2020) Inhibition of tumor propellant glutathione peroxidase 4 induces ferroptosis in cancer cells and enhances anticancer effect of cisplatin. J Cell Physiol 235:3425–3437

182 Zheng J, Conrad M (2020) The metabolic underpinnings of ferroptosis. Cell Metabol

183 Zhu J, Berisa M, Schwörer S, Qin W, Cross JR, Thompson CB (2019) Transsulfuration activity can support cell growth upon extracellular cysteine limitation. Cell Metab 30(865–876):

184 Zong Y, Feng S, Yu C, Cheng J, Lu G (2017) Up-regulated ATF4 expression increases cell sensitivity to apoptosis in response to radiation. Cell Physiol Biochem 41:784–794

185 Zou Y, Schreiber SL (2020) Progress in understanding ferroptosis and challenges in its targeting for therapeutic benefit. Cell Chem Biol 27:463–471

186 Zou Y, Palte MJ, Deik AA, Li H, Eaton JK, Wang W, Tseng Y-Y, Deasy R, Kost-Alimova M, Dančík V (2019) A GPX4-dependent cancer cell state underlies the clear-cell morphology and confers sensitivity to ferroptosis. Nat Commun 10:1–13

187 Zou Y, Henry WS, Ricq EL, Graham ET, Phadnis VV, Maretich P, Paradkar S, Boehnke N, Deik AA, Reinhardt F (2020a) Plasticity of ether lipids promotes ferroptosis susceptibility and evasion. Nature 585:603–608

188 Zou Y, Li H, Graham ET, Deik AA, Eaton JK, Wang W, Sandoval-Gomez G, Clish CB, Doench JG, Schreiber SL (2020b) Cytochrome P450 oxidoreductase contributes to phospholipid peroxidation in ferroptosis. Nat Chem Biol 16:302–309