The Ferroptosis Pathway

 

Death is part of the natural process of all living things, including individual cells. This process can occur in a variety of ways, and new pathways of cell death continue to be discovered. One of them, named ferroptosis, was first described in 2012 as a nonapoptotic, iron-dependent form of cell death.1 Years earlier, in the search for compounds that are selectively lethal to RAS-mutated tumor cells, researchers already identified two structurally independent small molecules named erastin and RSL3 that were able to induce a unique form of cell death.2 Further investigation revealed that this type of cell death does not share classic features of apoptosis such as caspase activation and chromatin fragmentation and is characterized by the iron-dependent accumulation of lipid hydroperoxides to lethal levels. In contrast, cells that undergo ferroptosis seem to exhibit distinct morphological characteristics such as shrunken and damaged mitochondria.3

While several proteins have been shown to regulate ferroptosis, glutathione peroxidase 4 (GPX4) is the central enzyme of this pathway. GPX4 effectively inhibits ferroptosis by reducing and thus limiting lipid peroxides and reactive oxygen species (ROS).4 This process requires the substrate glutathione (GSH), which is provided by the enzyme xCT via an intermediate step. Ferroptosis Signaling Pathway

Figure: Simplified ferroptotic cascade. Free iron accumulation is an initiator of ferroptosis. GPX4 normally inhibits ferroptosis by limiting lipid peroxides generated by ROS. This process requires the substrate GSH, which is provided by the enzyme xCT. (Adapted from Dodson et al., 2019, created with BioRender.com)

Since its initial discovery, ferroptosis has attracted great interest in its process and function. According to PubGrade  , the number of publications has increased exponentially in past years, from 405 in 2019, 849 in 2020, to 1670 in 2021. Rockland's portfolio contains numerous antibodies against key components of the ferroptosis pathway that can help to further unravel the underlying mechanisms and thereby pave the way for new applications in cancer therapy, the treatment of neurodegenerative diseases, and in inflammation.

 

Antibodies Against Modulators of Ferroptosis

Numerous signaling pathways and their associated proteins have an impact on ferroptosis and regulate this process. (Table adapted from Tang et al., 2021)

 

Calcium Pathway

Dysregulated ORAI1-mediated Ca2+ influx contributes to ferroptosis induced by GSH depletion.7

Product Clonality Reactivity Applications
ORAI1 Antibody Polyclonal Human WB
ORAI1 Antibody Polyclonal Human, Mouse WB, IHC, IF, ELISA
ORAI1 Antibody Polyclonal Human, Mouse WB, IHC, IF, ELISA
ORAI1 Antibody [3F6H5] Monoclonal Human, Mouse, Rat WB, IHC, IF, ELISA
ORAI1 Antibody [6D11A11] Monoclonal Human, Mouse, Rat WB, IHC, IF, ELISA

 

Cell Adhesion

Cadherin-mediated intercellular interactions suppress ferroptosis by activating intracellular NF2.8

Product Clonality Reactivity Applications
NF2 phospho S518 Antibody Polyclonal Mouse WB, IF, ELISA

 

Cysteine Metabolism

The availability of free cysteine determines the extent of GSH synthesis and protection against ferroptosis.9

Product Clonality Reactivity Applications
ATF3 Antibody Polyclonal Human WB, ELISA
CD44 Antibody Polyclonal Human WB, ELISA
MUC1 Antibody Polyclonal Human, Mouse WB, ELISA
xCT Antibody Polyclonal Human WB, FC, IF, ELISA

 

DNA Damage Pathway

ATM has been identified as a target for tumor cell ferroptosis, as it can be activated by radiotherapy and increases lipid oxidative damage.10

Product Clonality Reactivity Applications
ATM Protein Kinase S1981 Antibody Polyclonal Human, Mouse WB, IHC, IF, FC, ELISA
ATM phospho S1981 Antibody Polyclonal Human WB, ELISA
ATM phospho S1981 Antibody Monoclonal Human, Mouse, Rat WB, IHC, IF, ChIP, IP, FC, ELISA
ATM phospho S1981 Antibody Monoclonal Human, Mouse WB, IHC, IF, IP, ELISA
ATM phospho S1981 Biotin Conjugated Antibody Monoclonal Human, Mouse, Rat WB, ELISA
ATM phospho S1981 Peroxidase Conjugated Antibody Monoclonal Human, Mouse, Rat WB, ELISA
TFAM Antibody Polyclonal Human, Mouse, Rat WB

 

Epithelial–Mesenchymal Transition Pathway 

ZEB1 provides a bridge between mesenchymal gene expression and lipid peroxide susceptibility.11

Product Clonality Reactivity Applications
ZEB1 Antibody Polyclonal Human WB, IHC, IF, ELISA

 

ER Stress

Ferroptosis is associated with increased ER stress. The chaperone GRP78 (through activation of ATF4) inhibits GPX4 degradation and promotes oxidative stress resistance.12

Product Clonality Reactivity Applications
ATF4 Antibody Monoclonal Human, Rat WB, IHC, IF
GRP78 Antibody Polyclonal Broad WB, IF
GRP78 Antibody Monoclonal Broad WB, IF
GRP78 Antibody Monoclonal Broad WB

 

Glutamine Metabolism

GLS2-mediated glutamate production is required for erastin-induced ferroptosis.13

Product Clonality Reactivity Applications
GLS2 Antibody Polyclonal Human, Mouse, Rat WB, IHC, IF, ELISA

 

Iron Metabolism

Iron is required for the accumulation of lipid peroxides. In this context, the iron carrier protein transferrin plays a key role in the import of iron into the cell.2

Product Clonality Reactivity Applications
CISD2 Antibody Polyclonal Human, Mouse, Rat WB, IHC, IF, ELISA
HO-1 Antibody Polyclonal Human, Mouse, Rat, Dog WB
HO-1 Antibody Monoclonal Broad WB, IHC, IF, IP
HSPB2 (MKBP) Antibody Polyyclonal Human, Mouse, Rat WB, IF
Hsp25/Hsp27 Antibody Monoclonal Broad WB, IHC, IF, IP, FC, ELISA
HSP27 Antibody Monoclonal Human WB, ELISA
SLC40A1 Antibody Polyclonal Human WB, IF, ELISA
Mouse Transferrin Antibody Polyclonal Mouse EM, ELISA
Transferrin Antibody Polyclonal Human WB, ELISA
Transferrin Antibody Polyclonal Human WB, IHC, ELISA

 

KRAS Pathway

Mutations in the oncogene B-raf render cells more susceptible to erastin-induced ferroptosis.14

Product Clonality Reactivity Applications
B-raf Antibody Polyclonal Human, Mouse WB, IHC, IF, ELISA
B-raf Antibody Polyclonal Human, Mouse, Rat WB, ELISA

 

Lipid Metabolism

Glutathione peroxidase 4 (GPX4) is the central enzyme of the ferroptosis pathway. GPX4 effectively inhibits ferroptosis by reducing and thus limiting lipid peroxides and reactive oxygen species.4

Product Clonality Reactivity Applications
Glutathione Peroxidase 4 Antibody Polyclonal Guinea Pig, Mouse, Rat WB, ELISA
HIF-1-alpha Antibody Monoclonal Bovine, Human, Mouse, Rat WB, IHC, IF, ELISA
HIF-1-alpha hydroxy P564 Antibody Polyclonal Human WB, ELISA
HIF2 alpha Antibody Monoclonal Human WB, IHC
MDM2 Antibody Polyclonal Mouse WB, ELISA
Mdm2 phospho S185 Antibody Polyclonal Human, Mouse WB, ELISA

 

Lysosome & Autophagy

Several autophagy-related genes modulate ferroptosis by autophagic degradation of cellular iron storage proteins.15

Product Clonality Reactivity Applications
ATG3 Antibody Polyclonal Human, Mouse, Rat WB, IHC, IF, ELISA
ATG5 Antibody Polyclonal Human, Mouse WB, IHC, ELISA
ATG5 Antibody Polyclonal Human, Mouse, Rat WB, IHC, IF, ELISA
ATG8 Antibody Polyclonal Human, Mouse, Rat WB, IHC
ATG13 Antibody Polyclonal Human WB, ELISA
ATG13 phospho S318 Antibody Polyclonal Human WB, IF, FC, ELISA, Dot Blot
BECLIN1 Antibody Polyclonal Human, Mouse WB, IHC, IF, ELISA
Beclin 1 Antibody Polyclonal Human, Mouse WB, IHC, IF, ELISA
HSP90 total Antibody Monoclonal Human, Mouse, Rat WB, IHC, IF, IP
PINK1 Antibody Polyclonal Human, Mouse, Rat WB, IHC, IF, ELISA
PINK1 truncated Antibody Polyclonal Human, Mouse WB, IF, ELISA
PINK1 Antibody Monoclonal Human, Mouse, Rat WB, IHC, IF
RAB7 Antibody Polyclonal Human, Mouse WB, IHC, IF
SQSTM1 Antibody Polyclonal Human, Mouse, Rat WB, IHC, IF, ELISA
SQSTM1/p62 Antibody Polyclonal Human, Mouse WB, IHC, IF, ELISA
STAT3 (Internal) Antibody Polyclonal Human Dot Blot
STAT3 R31-Me2a Antibody Polyclonal Human Dot Blot
STAT3 phospho Y705 Antibody Polyclonal Human WB, IHC, ELISA
ULK1 Antibody Polyclonal Human, Mouse, Rat WB, IHC, IF, ELISA
ULK2 Antibody Polyclonal Human WB, IHC, IF, ELISA

 

Mitochondrial Function

The ferroptotic small molecules, erastin and artesunate, induce pro-apoptotic PUMA expression.16

Product Clonality Reactivity Applications
BID Antibody Polyclonal Human, Mouse WB, IHC, IF, ELISA
BID Antibody Polyclonal Human, Mouse WB, ELISA
NEDD4 Antibody Polyclonal Human WB, IF, ELISA
PUMA Antibody Polyclonal Human WB, IHC, IF, ELISA
PUMA Antibody Polyclonal Human, Mouse WB, IHC, IF, ELISA
PUMA Antibody [10D4G7] Monoclonal Human, Rat WB, ELISA
PUMA Antibody [2A9G5] Monoclonal Human, Mouse, Rat WB, ELISA
PUMA Antibody [2A8F6] Monoclonal Human, Rat WB, ELISA
PUMA Antibody [10C5G1] Monoclonal Human, Rat WB, ELISA

 

NRF2 Pathway

NRF2 is an important transcriptional regulator of anti-ferroptotic genes and is itself regulated by enzymes such as KEAP1.5

Product Clonality Reactivity Applications
ACVR1B Antibody Polyclonal Human, Mouse WB, ELISA
CDKN2A Antibody Polyclonal Human, Mouse, Rat WB, IHC, IF, ELISA
Nrf2 Antibody Polyclonal Human, Mouse WB, ELISA
PKR Antibody Polyclonal Human, Mouse, Rat WB, IHC, IF, ELISA
PKR Antibody Polyclonal Human, Rat WB, IHC, ELISA
KEAP1 Antibody Polyclonal Human, Mouse, Rat WB, IF, ELISA
TGF Beta Receptor 1 Antibody Polyclonal Human, Mouse WB, IHC, FC, ELISA

 

NOX Pathway

The NOX family of proteins promote lipid peroxidation in ferroptosis via ROS production.6

Product Clonality Reactivity Applications
Nox1 Antibody Polyclonal Mouse, Rat WB, IHC
NOX1 Antibody Polyclonal Human WB, IHC, IF, ELISA
NOX2 Antibody Polyclonal Human, Mouse, Rat WB, IHC
NOX2 Antibody Polyclonal Human, Mouse, Rat WB, IHC, IF, ELISA
NOX4 Antibody Polyclonal Human, Mouse, Rat WB, IHC, IF, ELISA

 

RNS Pathway

Scaffolding protein Cav-1 is involved in erastin-induced ferroptosis and links reactive nitrogen species (RNS) to ferroptosis.17

Product Clonality Reactivity Applications
Caveolin-1 Antibody Polyclonal Human WB
Caveolin-1 Antibody Polyclonal Human WB
Caveolin-1 phospho S168 Antibody Polyclonal Human WB
NOS2 Antibody Polyclonal Human, Mouse, Rat WB

 

References

  1. Dixon SJ, Lemberg KM, Lamprecht MR, Skouta R, Zaitsev EM, Gleason CE, Patel DN, Bauer AJ, Cantley AM, Yang WS, Morrison B 3rd, Stockwell BR. Ferroptosis: an iron-dependent form of nonapoptotic cell death. Cell. 2012 May 25;149(5):1060-72.
  2. Yang WS, Stockwell BR. Synthetic lethal screening identifies compounds activating iron-dependent, nonapoptotic cell death in oncogenic-RAS-harboring cancer cells. Chem Biol. 2008 Mar;15(3):234-45.
  3. Stockwell BR, Friedmann Angeli JP, Bayir H, et al. Ferroptosis: A Regulated Cell Death Nexus Linking Metabolism, Redox Biology, and Disease. Cell. 2017;171(2):273-285.
  4. Yang WS, SriRamaratnam R, Welsch ME, Shimada K, Skouta R, Viswanathan VS, Cheah JH, Clemons PA, Shamji AF, Clish CB, Brown LM, Girotti AW, Cornish VW, Schreiber SL, Stockwell BR. Regulation of ferroptotic cancer cell death by GPX4. Cell. 2014 Jan 16;156(1-2):317-331.
  5. Dodson M, Castro-Portuguez R, Zhang DD. NRF2 plays a critical role in mitigating lipid peroxidation and ferroptosis. Redox Biol. 2019 May;23:101107.
  6. Tang D, Chen X, Kang R, Kroemer G. Ferroptosis: molecular mechanisms and health implications. Cell Res. 2021 Feb;31(2):107-125.
  7. Henke N, Albrecht P, Bouchachia I, Ryazantseva M, Knoll K, Lewerenz J, Kaznacheyeva E, Maher P, Methner A. The plasma membrane channel ORAI1 mediates detrimental calcium influx caused by endogenous oxidative stress. Cell Death Dis. 2013 Jan 24;4(1):e470.
  8. Wu J, Minikes AM, Gao M, Bian H, Li Y, Stockwell BR, Chen ZN, Jiang X. Intercellular interaction dictates cancer cell ferroptosis via NF2-YAP signalling. Nature. 2019 Aug;572(7769):402-406.
  9. Fujii J, Homma T, Kobayashi S. Ferroptosis caused by cysteine insufficiency and oxidative insult. Free Radic Res. 2020 Dec;54(11-12):969-980.
  10. Lang X, Green MD, Wang W, Yu J, Choi JE, Jiang L, Liao P, Zhou J, Zhang Q, Dow A, Saripalli AL, Kryczek I, Wei S, Szeliga W, Vatan L, Stone EM, Georgiou G, Cieslik M, Wahl DR, Morgan MA, Chinnaiyan AM, Lawrence TS, Zou W. Radiotherapy and Immunotherapy Promote Tumoral Lipid Oxidation and Ferroptosis via Synergistic Repression of SLC7A11. Cancer Discov. 2019 Dec;9(12):1673-1685.
  11. Viswanathan, V., Ryan, M., Dhruv, H. et al. Dependency of a therapy-resistant state of cancer cells on a lipid peroxidase pathway. Nature 547, 453–457 (2017).
  12. Zhu S, Zhang Q, Sun X, Zeh HJ 3rd, Lotze MT, Kang R, Tang D. HSPA5 Regulates Ferroptotic Cell Death in Cancer Cells. Cancer Res. 2017 Apr 15;77(8):2064-2077.
  13. Gao M, Monian P, Quadri N, Ramasamy R, Jiang X. Glutaminolysis and Transferrin Regulate Ferroptosis. Mol Cell. 2015 Jul 16;59(2):298-308.
  14. Yagoda N, von Rechenberg M, Zaganjor E, Bauer AJ, Yang WS, Fridman DJ, Wolpaw AJ, Smukste I, Peltier JM, Boniface JJ, Smith R, Lessnick SL, Sahasrabudhe S, Stockwell BR. RAS-RAF-MEK-dependent oxidative cell death involving voltage-dependent anion channels. Nature. 2007 Jun 14;447(7146):864-8.
  15. Gao M, Monian P, Pan Q, Zhang W, Xiang J, Jiang X. Ferroptosis is an autophagic cell death process. Cell Res. 2016 Sep;26(9):1021-32.
  16. Hong SH, Lee DH, Lee YS, Jo MJ, Jeong YA, Kwon WT, Choudry HA, Bartlett DL, Lee YJ. Molecular crosstalk between ferroptosis and apoptosis: emerging role of ER stress-induced p53-independent PUMA expression. Oncotarget. 2017 Dec 8;8(70):115164-115178.
  17. Deng G, Li Y, Ma S, Gao Z, Zeng T, Chen L, Ye H, Yang M, Shi H, Yao X, Zeng Z, Chen Y, Song Y, Liu B, Gao L. Caveolin-1 dictates ferroptosis in the execution of acute immune-mediated hepatic damage by attenuating nitrogen stress. Free Radic Biol Med. 2020 Feb 20;148:151-161.