Annexin A1

From Wikipedia, the free encyclopedia
  (Redirected from Lipocortin-1)
Jump to: navigation, search
Annexin A1

PDB rendering based on 1ain.
Available structures
PDB Ortholog search: PDBe, RCSB
Symbols ANXA1 ; ANX1; LPC1
External IDs OMIM151690 MGI96819 HomoloGene563 GeneCards: ANXA1 Gene
RNA expression pattern
PBB GE ANXA1 201012 at tn.png
More reference expression data
Species Human Mouse
Entrez 301 16952
Ensembl ENSG00000135046 ENSMUSG00000024659
UniProt P04083 P10107
RefSeq (mRNA) NM_000700 NM_010730
RefSeq (protein) NP_000691 NP_034860
Location (UCSC) Chr 9:
75.77 – 75.79 Mb
Chr 19:
20.37 – 20.39 Mb
PubMed search [1] [2]

Annexin A1 also known as lipocortin I is a protein that in humans is encoded by the ANXA1 gene.[1]


Annexin I belongs to the annexin family of Ca2+-dependent phospholipid-binding proteins that have a molecular weight of approximately 35,000 to 40,000 and are preferentially located on the cytosolic face of the plasma membrane. Annexin I protein has an apparent relative molecular mass of 40 kDa, with phospholipase A2 inhibitory activity.[2]

Clinical significance[edit]

Effect on innate and adaptive immunity[edit]

Glucocorticoids, such as budesonide, cortisol, beclomethasone, are anti-inflammatory mediators that have been successfully used for therapeutic purposes. The usage of glucocorticoids in long term period, however, is bound with a series of possible side effects like immunodeficiency, adrenal insufficiency, and several more. Glucocorticoids exhibit their anti-inflammatory properties by two major mechanisms: genomic mechanisms (involving transactivation or transrepression of gene transcription) and nongenomic mechanisms (that are rapid and independent of de novo protein synthesis). Glucocorticoids regulate the synthesis and function of annexin A1 possibly through a combination of both genomic and non-genomic processes, depending on the cell type and the time of induction.[3]

In resting conditions, human and mouse neutrophils, monocytes and macrophages constitutively contain high levels of annexin A1 in their cytoplasm. Following cell activation (for example, by neutrophil adhesion to endothelial-cell monolayers), annexin A1 is promptly mobilized to the cell surface and secreted. Annexin A1 promotes neutrophil detachment, apoptosis and phagocytosis of apoptotic neutrophils by macrophages. On the other hand, it downregulates the levels of neutrophil transmigration.In vitro and in vivo analyses show that exogenous and endogenous annexin A1 counter-regulate the activities of innate immune cells, in particular extra vasation and the generation of proinflammatory mediators, and this ensures that a sufficient level of activation is reached but not exceeded.[3]

Annexin A1 has important opposing properties during innate and adaptive immune responses, as it inhibits innate immune cells and promotes T-cell activation. Activation of T cells results in the release of annexin A1 and the expression of its receptor. This pathway seems to fine-tune the strength of TCR signalling. Higher expression of annexin A1 during pathological conditions could increase the strength of TCR signalling through the mitogen-activated protein kinase signalling pathway, thereby causing a state of hyperactivation of T cells.[3]

Thus, several experimental studies had been performed in order to elucidate further the role of annexin A1 and of its formyl peptide receptor (FPR) on innate and adaptive immune systems. There were evidences that suggested possibility for treatment of some autoimmune diseases, for example rheumatoid arthritis[4] and systemic lupus erythematosus, via targeting of annexin A1 expression and secretion.


Since phospholipase A2 is required for the biosynthesis of the potent mediators of inflammation, prostaglandins, and leukotrienes, annexin I may have potential anti-inflammatory activity.[2]

Glucocorticoids stimulate production of lipocortin.[5] In this way, synthesis of eicosanoids are inhibited.


Annexin I has been of interest for use as a potential anticancer drug. Upon induction by modified NSAIDS and other potent anti-inflammatory drugs, annexin I inhibits the NF-κB signal transduction pathway, which is exploited by cancerous cells to proliferate and avoid apoptosis. ANXA1 inhibits the activation of NF-κB by binding to the p65 subunit.[6]


The gene for annexin A1 (ANXA1) is upregulated in hairy cell leukemia. ANXA1 protein expression is specific to hairy cell leukemia. Detection of ANXA1 (by immunocytochemical means) reportedly provides a simple, highly sensitive and specific assay for the diagnosis of hairy cell leukemia.[7]

Breast cancer[edit]

Exposure of MCF-7 breast cancer cells to high physiological levels (up to 100 nM) of estrogen lead to an up-regulation of annexin-1 expression partially through the activation of CREB, and dependent on activation of the estrogen receptor alpha. Treatment of MCF-7 cells with physiological levels of estrogen (1 nM) induced proliferation while high pregnancy levels of estrogen (100 nM) induced a growth arrest of MCF-7 cells. Silencing of ANXA1 with specific siRNA reverses the estrogen-dependent proliferation as well as growth arrest. ANXA1 is lost in clinical breast cancer, indicating that the anti-proliferative protective function of ANXA1 against high levels of estrogen may be lost in breast cancer. This data suggests that ANXA1 may act as a tumor suppressor gene and modulate the proliferative functions of estrogens.[8]

Annexin-A1 has also been shown to be protective against DNA damage induced by heat in breast cancer cells, adding to the evidence that it has tumor suppressive and protective activities. When ANXA1 is silenced or lost in cancer, cells are more prone to DNA damage, indicating its unidentified diverse role in genome maintenance or integrity.[9]


  1. ^ Wallner BP, Mattaliano RJ, Hession C, Cate RL, Tizard R, Sinclair LK, Foeller C, Chow EP, Browing JL, Ramachandran KL (1986). "Cloning and expression of human lipocortin, a phospholipase A2 inhibitor with potential anti-inflammatory activity". Nature 320 (6057): 77–81. doi:10.1038/320077a0. PMID 2936963. 
  2. ^ a b "Entrez Gene: ANXA1 annexin A1". 
  3. ^ a b c Perretti M, D'Acquisto F (January 2009). "Annexin A1 and glucocorticoids as effectors of the resolution of inflammation". Nat. Rev. Immunol. 9 (1): 62–70. doi:10.1038/nri2470. PMID 19104500. 
  4. ^ Fulvio D'Acquisto, Ahmed Merghani, Emilio Lecona, Guglielmo Rosignoli, Karim Raza, Christopher D.,Buckley, Roderick J. Flower and Mauro Perretti, 2007, "Annexin-1 modulates T-cell activation and differentiation", Blood journal, vol.109, p.1095-1102
  5. ^ Peers SH, Smillie F, Elderfield AJ, Flower RJ (January 1993). "Glucocorticoid-and non-glucocorticoid induction of lipocortins (annexins) 1 and 2 in rat peritoneal leucocytes in vivo". British Journal of Pharmacology 108 (1): 66–72. PMC 1907693. PMID 8428216. 
  6. ^ Zhang Z, Huang L, Zhao W, Rigas B (March 2010). "Annexin 1 induced by anti-inflammatory drugs binds to NF-kappaB and inhibits its activation: anticancer effects in vitro and in vivo". Cancer Res. 70 (6): 2379–88. doi:10.1158/0008-5472.CAN-09-4204. PMC 2953961. PMID 20215502. 
  7. ^ Falini B, Tiacci E, Liso A, Basso K, Sabattini E, Pacini R, Foa R, Pulsoni A, Dalla Favera R, Pileri S (June 2004). "Simple diagnostic assay for hairy cell leukaemia by immunocytochemical detection of annexin A1 (ANXA1)". Lancet 363 (9424): 1869–70. doi:10.1016/S0140-6736(04)16356-3. PMID 15183626. 
  8. ^ Ang EZ, Nguyen HT, Sim HL, Putti TC, Lim LH (February 2009). "Annexin-1 regulates growth arrest induced by high levels of estrogen in MCF-7 breast cancer cells". Mol. Cancer Res. 7 (2): 266–74. doi:10.1158/1541-7786.MCR-08-0147. PMID 19208747. 
  9. ^ Nair S, Hande MP, Lim LH (August 2010). "Annexin-1 protects MCF7 breast cancer cells against heat-induced growth arrest and DNA damage". Cancer Lett. 294 (1): 111–7. doi:10.1016/j.canlet.2010.01.026. PMID 20163912. 

Further reading[edit]

  • Crompton MR, Moss SE, Crumpton MJ (1988). "Diversity in the lipocortin/calpactin family.". Cell 55 (1): 1–3. doi:10.1016/0092-8674(88)90002-5. PMID 2971450. 
  • Lim LH, Pervaiz S (2007). "Annexin 1: the new face of an old molecule.". FASEB J. 21 (4): 968–75. doi:10.1096/fj.06-7464rev. PMID 17215481. 
  • Dawson SJ, White LA (1992). "Treatment of Haemophilus aphrophilus endocarditis with ciprofloxacin.". J. Infect. 24 (3): 317–20. doi:10.1016/S0163-4453(05)80037-4. PMID 1602151. 
  • Ando Y, Imamura S, Owada MK, Kannagi R (1991). "Calcium-induced intracellular cross-linking of lipocortin I by tissue transglutaminase in A431 cells. Augmentation by membrane phospholipids.". J. Biol. Chem. 266 (2): 1101–8. PMID 1670773. 
  • Kovacic RT, Tizard R, Cate RL, et al. (1991). "Correlation of gene and protein structure of rat and human lipocortin I.". Biochemistry 30 (37): 9015–21. doi:10.1021/bi00101a015. PMID 1832554. 
  • Varticovski L, Chahwala SB, Whitman M, et al. (1988). "Location of sites in human lipocortin I that are phosphorylated by protein tyrosine kinases and protein kinases A and C.". Biochemistry 27 (10): 3682–90. doi:10.1021/bi00410a024. PMID 2457390. 
  • Pepinsky RB, Sinclair LK, Chow EP, O'Brine-Greco B (1990). "A dimeric form of lipocortin-1 in human placenta.". Biochem. J. 263 (1): 97–103. PMC 1133395. PMID 2532504. 
  • Kaplan R, Jaye M, Burgess WH, et al. (1988). "Cloning and expression of cDNA for human endonexin II, a Ca2+ and phospholipid binding protein.". J. Biol. Chem. 263 (17): 8037–43. PMID 2967291. 
  • Huebner K, Cannizzaro LA, Frey AZ, et al. (1988). "Chromosomal localization of the human genes for lipocortin I and lipocortin II.". Oncogene Res. 2 (4): 299–310. PMID 2969496. 
  • Biemann K, Scoble HA (1987). "Characterization by tandem mass spectrometry of structural modifications in proteins.". Science 237 (4818): 992–8. doi:10.1126/science.3303336. PMID 3303336. 
  • Arcone R, Arpaia G, Ruoppolo M, et al. (1993). "Structural characterization of a biologically active human lipocortin 1 expressed in Escherichia coli.". Eur. J. Biochem. 211 (1-2): 347–55. doi:10.1111/j.1432-1033.1993.tb19904.x. PMID 8425544. 
  • Weng X, Luecke H, Song IS, et al. (1993). "Crystal structure of human annexin I at 2.5 A resolution.". Protein Sci. 2 (3): 448–58. doi:10.1002/pro.5560020317. PMC 2142391. PMID 8453382. 
  • Mailliard WS, Haigler HT, Schlaepfer DD (1996). "Calcium-dependent binding of S100C to the N-terminal domain of annexin I.". J. Biol. Chem. 271 (2): 719–25. doi:10.1074/jbc.271.2.719. PMID 8557678. 
  • Morgan RO, Fernández MP (1996). "A BC200-derived element and Z-DNA as structural markers in annexin I genes: relevance to Alu evolution and annexin tetrad formation.". J. Mol. Evol. 41 (6): 979–85. PMID 8587144. 
  • Almawi WY, Saouda MS, Stevens AC, et al. (1997). "Partial mediation of glucocorticoid antiproliferative effects by lipocortins.". J. Immunol. 157 (12): 5231–9. PMID 8955167. 
  • Croxtall JD, Wu HL, Yang HY, et al. (1998). "Lipocortin 1 co-associates with cytokeratins 8 and 18 in A549 cells via the N-terminal domain.". Biochim. Biophys. Acta 1401 (1): 39–51. doi:10.1016/S0167-4889(97)00120-1. PMID 9459484. 
  • Gao J, Li Y, Yan H (1999). "NMR solution structure of domain 1 of human annexin I shows an autonomous folding unit.". J. Biol. Chem. 274 (5): 2971–7. doi:10.1074/jbc.274.5.2971. PMID 9915835. 
  • Manda R, Kohno T, Matsuno Y, et al. (1999). "Identification of genes (SPON2 and C20orf2) differentially expressed between cancerous and noncancerous lung cells by mRNA differential display.". Genomics 61 (1): 5–14. doi:10.1006/geno.1999.5939. PMID 10512675. 

External links[edit]

This article incorporates text from the United States National Library of Medicine, which is in the public domain.