# Growth factor

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Protein or other substance that stimulates cellular proliferation

"Growth factors" redirects here. For the journal, see [Growth Factors (journal)](/source/Growth_Factors_(journal)).

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A **growth factor** is a naturally occurring substance capable of stimulating [cell proliferation](/source/Cell_proliferation), [wound healing](/source/Wound_healing), and occasionally [cellular differentiation](/source/Cellular_differentiation).[1] Usually it is a secreted [protein](/source/Protein) or a [steroid hormone](/source/Steroid_hormone).

## Comparison to cytokines

*Growth factor* is sometimes used interchangeably among scientists with the term *[cytokine](/source/Cytokine).*[2] Historically, cytokines were associated with [hematopoietic](/source/Hematopoietic) (blood and lymph forming) cells and [immune system](/source/Immune_system) cells (e.g., [lymphocytes](/source/Lymphocyte) and tissue cells from [spleen](/source/Spleen), [thymus](/source/Thymus), and [lymph nodes](/source/Lymph_node)). For the [circulatory system](/source/Circulatory_system) and [bone marrow](/source/Bone_marrow) in which cells can occur in a liquid suspension and not bound up in solid [tissue](/source/Tissue_(biology)), it makes sense for them to communicate by soluble, circulating protein [molecules](/source/Molecule). However, as different lines of research converged, it became clear that some of the same signaling proteins which the hematopoietic and immune systems use were also being used by all sorts of other cells and tissues, during development and in the mature organism.

While *growth factor* implies a positive effect on [cell proliferation](/source/Cell_proliferation), *cytokine* is a neutral term with respect to whether a molecule affects proliferation. While some cytokines can be growth factors, such as [G-CSF](/source/Granulocyte_colony-stimulating_factor) and [GM-CSF](/source/Granulocyte_macrophage_colony-stimulating_factor), others have an inhibitory effect on [cell growth](/source/Cell_growth) or cell proliferation. Some cytokines, such as [Fas ligand](/source/Fas_ligand), are used as "death" signals; they cause target cells to undergo programmed [cell death](/source/Cell_death) or *[apoptosis](/source/Apoptosis)*.

## List of classes

This list is incomplete; you can help by adding missing items. (February 2011)

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Individual growth factor proteins tend to occur as members of larger families of structurally and [evolutionarily](/source/Evolution) related proteins. There are many families, some of which are listed below:

- [Adrenomedullin](/source/Adrenomedullin) (AM)

- [Angiopoietin](/source/Angiopoietin) (Ang)

- [Autocrine motility factor](/source/Autocrine_motility_factor)

- [Bone morphogenetic proteins](/source/Bone_morphogenetic_protein) (BMPs)

- Ciliary neurotrophic factor family

- [Colony-stimulating factors](/source/Colony-stimulating_factor)

- [Epidermal growth factor](/source/Epidermal_growth_factor) (EGF)

- [Ephrins](/source/Ephrin)

- [Erythropoietin](/source/Erythropoietin) (EPO)

- [Fibroblast growth factor](/source/Fibroblast_growth_factor) (FGF)

- [Foetal Bovine Somatotrophin](/source/Bovine_somatotropin) (FBS)

- [GDNF family of ligands](/source/GDNF_family_of_ligands)

- [Growth differentiation factor-9](/source/Growth_differentiation_factor-9) (GDF9)

- [Hepatocyte growth factor](/source/Hepatocyte_growth_factor) (HGF)

- [Hepatoma-derived growth factor](/source/Hepatoma-derived_growth_factor) (HDGF)

- [Insulin](/source/Insulin)

- [Insulin-like growth factors](/source/Insulin-like_growth_factor)

- Interleukins

- [Keratinocyte growth factor](/source/Keratinocyte_growth_factor) (KGF)

- [Migration-stimulating factor](/source/PRG4) (MSF)

- [Macrophage-stimulating protein](/source/Macrophage-stimulating_protein) (MSP), also known as hepatocyte growth factor-like protein (HGFLP)

- [Myostatin](/source/Myostatin) (GDF-8)

- [Neuregulins](/source/Neuregulin)

- [Neurotrophins](/source/Neurotrophins)

- [Placental growth factor](/source/Placental_growth_factor) (PGF)

- [Platelet-derived growth factor](/source/Platelet-derived_growth_factor) (PDGF)

- [Renalase](/source/Renalase) (RNLS) – Anti-apoptotic survival factor

- [T-cell growth factor](/source/T-cell_growth_factor) (TCGF)

- [Thrombopoietin](/source/Thrombopoietin) (TPO)

- [Transforming growth factors](/source/Transforming_growth_factor)

- [Tumor necrosis factor-alpha](/source/Tumor_necrosis_factor-alpha) (TNF-α)

- [Vascular endothelial growth factor](/source/Vascular_endothelial_growth_factor) (VEGF)

## In platelets

The [alpha granules](/source/Alpha_granule) in blood [platelets](/source/Platelet) contain growth factors PDGF, IGF-1, EGF, and TGF-β which begin healing of wounds by attracting and activating [macrophages](/source/Macrophage), [fibroblasts](/source/Fibroblast), and [endothelial cells](/source/Endothelial_cell).

## Uses in medicine

For the last two decades, growth factors have been increasingly used in the treatment of [hematologic](/source/Hematology) and [oncologic](/source/Oncology) diseases[3][4] and cardiovascular diseases[5][6] such as:

- [skin wound healing and regeneration of other tissues such as bone](https://en.wikipedia.org/w/index.php?title=Skin_wound_healing_and_regeneration_of_other_tissues_such_as_bone&action=edit&redlink=1) (PDGF-BB)

- [neutropenia](/source/Neutropenia)

- [myelodysplastic syndrome](/source/Myelodysplastic_syndrome) (MDS)

- [leukemias](/source/Leukemia)

- [aplastic anaemia](/source/Aplastic_anaemia)

- [bone marrow](/source/Bone_marrow) transplantation

- [angiogenesis](/source/Angiogenesis) for cardiovascular diseases

## See also

- [Angiogenesis](/source/Angiogenesis)

- [Bone growth factor](/source/Bone_growth_factor)

- [Cytokine](/source/Cytokine)

- [Growth factor receptor](/source/Growth_factor_receptor)

- [Human Genome Organisation](/source/Human_Genome_Organisation)

- [Mitogen](/source/Mitogen)

- [Neurotrophic factor](/source/Neurotrophic_factor)

- [Receptor (biochemistry)](/source/Receptor_(biochemistry))

- [Signal transduction](/source/Signal_transduction)

- [Wound healing § Overview of involved growth factors](/source/Wound_healing#Overview_of_involved_growth_factors)

## References

1. **[^](#cite_ref-1)** ["growth factor"](https://web.archive.org/web/20090628224336/http://www.mercksource.com/pp/us/cns/cns_hl_dorlands_split.jsp?pg=/ppdocs/us/common/dorlands/dorland/three/000038554.htm) at *[Dorland's Medical Dictionary](/source/Dorland's_medical_reference_works)*

1. **[^](#cite_ref-YorioClark2007_2-0)** Yorio T, Clark AF, Wax MB (2007). [*Ocular Therapeutics: Eye on New Discoveries*](https://books.google.com/books?id=7jVNuIt8vm4C&pg=PA88). Academic Press. p. 88. [ISBN](/source/ISBN_(identifier)) [978-0-12-370585-3](https://en.wikipedia.org/wiki/Special:BookSources/978-0-12-370585-3).

1. **[^](#cite_ref-3)** Cottler-Fox M, Klein HG (April 1994). "Transfusion support of hematology and oncology patients. The role of recombinant hematopoietic growth factors". *Archives of Pathology & Laboratory Medicine*. **118** (4): 417–20. [PMID](/source/PMID_(identifier)) [7909429](https://pubmed.ncbi.nlm.nih.gov/7909429).

1. **[^](#cite_ref-4)** Aaronson SA (November 1991). "Growth factors and cancer". *Science*. **254** (5035): 1146–53. [Bibcode](/source/Bibcode_(identifier)):[1991Sci...254.1146A](https://ui.adsabs.harvard.edu/abs/1991Sci...254.1146A). [doi](/source/Doi_(identifier)):[10.1126/science.1659742](https://doi.org/10.1126%2Fscience.1659742). [PMID](/source/PMID_(identifier)) [1659742](https://pubmed.ncbi.nlm.nih.gov/1659742).

1. **[^](#cite_ref-5)** Domouzoglou EM, Naka KK, Vlahos AP, Papafaklis MI, Michalis LK, Tsatsoulis A, Maratos-Flier E (September 2015). ["Fibroblast growth factors in cardiovascular disease: The emerging role of FGF21"](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4747916). *American Journal of Physiology. Heart and Circulatory Physiology*. **309** (6): H1029-38. [doi](/source/Doi_(identifier)):[10.1152/ajpheart.00527.2015](https://doi.org/10.1152%2Fajpheart.00527.2015). [PMC](/source/PMC_(identifier)) [4747916](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4747916). [PMID](/source/PMID_(identifier)) [26232236](https://pubmed.ncbi.nlm.nih.gov/26232236).

1. **[^](#cite_ref-6)** Gorenoi, Vitali; Brehm, Michael U.; Koch, Armin; Hagen, Anja (2017). ["Growth factors for angiogenesis in peripheral arterial disease"](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6481523). *The Cochrane Database of Systematic Reviews*. **2017** (6) CD011741. [doi](/source/Doi_(identifier)):[10.1002/14651858.CD011741.pub2](https://doi.org/10.1002%2F14651858.CD011741.pub2). [ISSN](/source/ISSN_(identifier)) [1469-493X](https://search.worldcat.org/issn/1469-493X). [PMC](/source/PMC_(identifier)) [6481523](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6481523). [PMID](/source/PMID_(identifier)) [28594443](https://pubmed.ncbi.nlm.nih.gov/28594443).

## External links

- [Growth+Factors](https://meshb.nlm.nih.gov/record/ui?name=Growth+Factors) at the U.S. National Library of Medicine [Medical Subject Headings](/source/Medical_Subject_Headings) (MeSH)

- [FGF5 in Hair Tonic Products](https://web.archive.org/web/20170223153745/https://www.evolisproducts.com.au/fgf-5-hair-loss/)

- [FGF1 in Cosmetic Products](https://web.archive.org/web/20100208230857/http://www.esheeesthetic.com/technology.php)

v t e Growth factors Fibroblast FGF receptor ligands: FGF1/FGF2/FGF5 FGF3/FGF4/FGF6 KGF FGF7/FGF10/FGF22 FGF8/FGF17/FGF18 FGF9/FGF16/FGF20 FGF homologous factors: FGF11(FHF3) FGF12(FHF1) FGF13(FHF2) FGF14(FHF4) hormone-like: FGF15/19 FGF15 FGF19 FGF21 FGF23 EGF-like domain TGFα EGF HB-EGF TGFβ pathway TGFβ TGFβ1 TGFβ2 TGFβ3 Insulin/IGF/ Relaxin family Insulin and Insulin-like growth factor IGF1 IGF2 Relaxin family peptide hormones INSL3 INSL4 INSL5 INSL6 Relaxin 1 2 3 Platelet-derived PDGFA PDGFB PDGFC PDGFD Vascular endothelial VEGF-A VEGF-B VEGF-C VEGF-D PGF Other Nerve Hepatocyte

v t e Cell signaling: cytokines By family Chemokine CCL CCL1 CCL2/MCP1 CCL3/MIP1α CCL4/MIP1β CCL5/RANTES CCL6 CCL7 CCL8 CCL9 CCL11 CCL12 CCL13 CCL14 CCL15 CCL16 CCL17 CCL18/PARC/DCCK1/AMAC1/MIP4 CCL19 CCL20 CCL21 CCL22 CCL23 CCL24 CCL25 CCL26 CCL27 CCL28 CXCL CXCL1/KC CXCL2 CXCL3 CXCL4 CXCL5 CXCL6 CXCL7 CXCL8/IL8 CXCL9 CXCL10 CXCL11 CXCL12 CXCL13 CXCL14 CXCL15 CXCL16 CXCL17 CX3CL CX3CL1 XCL XCL1 XCL2 TNF TNFA Lymphotoxin TNFB/LTA TNFC/LTB TNFSF4 TNFSF5/CD40LG TNFSF6 TNFSF7 TNFSF8 TNFSF9 TNFSF10 TNFSF11 TNFSF13 TNFSF13B EDA Interleukin Type I (grouped by receptor subunit) γ chain IL2/IL15 IL4/IL13 IL7 IL9 IL21 β chain IL3 IL5 GMCSF IL6 like/gp130 IL6 IL11 IL27 IL30 IL31 +non IL OSM LIF CNTF CTF1 IL12 family/IL12RB1 IL12 IL23 IL27 IL35 Other IL14 IL16 IL32 IL34 Type II IL10 family IL10/IL22 IL19 IL20 IL24 IL26 Interferon type III IL28/IFNL2+3 IL29/IFNL1 Interferon I IFNA1 IFNA2 IFNA4 IFNA5 IFNA6 IFNA7 IFNA8 IFNA10 IFNA13 IFNA14 IFNA16 IFNA17 IFNA21 IFNB1 IFNK IFNW1 II IFNG Ig superfamily IL1 family: IL1A/IL1F1 IL1B/IL1F2 1Ra/IL1F3 IL1F5 IL1F6 IL1F7 IL1F8 IL1F9 IL1F10 33/IL1F11 18/IL1G IL17 family IL17/IL25 (IL17A) Other Hematopoietic KITLG Colony-stimulating factor SPP1 MIF By function/ cell proinflammatory cytokine IL1 TNFA Monokine Lymphokine Th1 IFNγ TNFβ Th2 IL4 IL5 IL6 IL10 IL13 Category Commons

v t e Wound healing Fibrosis Maggot therapy Granulation tissue Growth factor Scar Stem cell Angiogenesis Intussusception Vasculogenesis Wound licking

v t e Growth factor receptor modulators Angiopoietin Agonists: Angiopoietin 1 Angiopoietin 4 Antagonists: Angiopoietin 2 Angiopoietin 3 Kinase inhibitors: Altiratinib CE-245677 Rebastinib Antibodies: Evinacumab (against angiopoietin 3) Nesvacumab (against angiopoietin 2) CNTF Agonists: Axokine CNTF Dapiclermin EGF (ErbB) EGF (ErbB1/HER1) Agonists: Amphiregulin Betacellulin EGF (urogastrone) Epigen Epiregulin Heparin-binding EGF-like growth factor (HB-EGF) Murodermin Nepidermin Transforming growth factor alpha (TGFα) Kinase inhibitors: Afatinib Agerafenib Brigatinib Canertinib Dacomitinib Erlotinib Gefitinib Grandinin Icotinib Lapatinib Neratinib Osimertinib Vandetanib WHI-P 154 Antibodies: Cetuximab Depatuxizumab Depatuxizumab mafodotin Futuximab Imgatuzumab Matuzumab Necitumumab Nimotuzumab Panitumumab Zalutumumab ErbB2/HER2 Agonists: Unknown/none Antibodies: Ertumaxomab Pertuzumab Trastuzumab Trastuzumab deruxtecan Trastuzumab duocarmazine Trastuzumab emtansine Kinase inhibitors: Afatinib Lapatinib Mubritinib Neratinib Tucatinib ErbB3/HER3 Agonists: Neuregulins (heregulins) (1, 2, 6 (neuroglycan C)) Antibodies: Duligotuzumab Patritumab Seribantumab ErbB4/HER4 Agonists: Betacellulin Epigen Heparin-binding EGF-like growth factor (HB-EGF) Neuregulins (heregulins) (1, 2, 3, 4, 5 (tomoregulin, TMEFF)) FGF FGFR1 Agonists: Ersofermin FGF (1, 2 (bFGF), 3, 4, 5, 6, 8, 10 (KGF2), 20) Repifermin Selpercatinib Trafermin Velafermin FGFR2 Agonists: Ersofermin FGF (1, 2 (bFGF), 3, 4, 5, 6, 7 (KGF), 8, 9, 10 (KGF2), 17, 18, 22) Palifermin Repifermin Selpercatinib Sprifermin Trafermin Antibodies: Aprutumab Aprutumab ixadotin Kinase inhibitors: Infigratinib FGFR3 Agonists: Ersofermin FGF (1, 2 (bFGF), 4, 8, 9, 18, 23) Selpercatinib Sprifermin Trafermin Antibodies: Burosumab (against FGF23) FGFR4 Agonists: Ersofermin FGF (1, 2 (bFGF), 4, 6, 8, 9, 19) Trafermin Unsorted Agonists: FGF15/19 HGF (c-Met) Agonists: Fosgonimeton Hepatocyte growth factor Potentiators: Dihexa (PNB-0408) Kinase inhibitors: Altiratinib AM7 AMG-458 Amuvatinib BMS-777607 Cabozantinib Capmatinib Crizotinib Foretinib Golvatinib INCB28060 JNJ-38877605 K252a MK-2461 PF-04217903 PF-2341066 PHA-665752 Savolitinib SU-11274 Tivantinib Antibodies: Emibetuzumab Ficlatuzumab Flanvotumab Onartuzumab Rilotumumab Telisotuzumab Telisotuzumab vedotin IGF IGF-1 Agonists: des(1-3)IGF-1 Insulin-like growth factor-1 (somatomedin C) IGF-1 LR3 Insulin-like growth factor-2 (somatomedin A) Insulin Mecasermin Mecasermin rinfabate Kinase inhibitors: BMS-754807 Linsitinib NVP-ADW742 NVP-AEW541 OSl-906 Antibodies: AVE-1642 Cixutumumab Dalotuzumab Figitumumab Ganitumab Robatumumab R1507 Teprotumumab Xentuzumab (against IGF-1 and IGF-2) IGF-2 Agonists: Insulin-like growth factor-2 (somatomedin A) Antibodies: Dusigitumab Xentuzumab (against IGF-1 and IGF-2) Others Binding proteins: IGFBP (1, 2, 3, 4, 5, 6, 7) Cleavage products/derivatives with unknown target: Glypromate (GPE, (1-3)IGF-1) Trofinetide LNGF (p75NTR) Agonists: BDNF BNN-20 BNN-27 Cenegermin DHEA DHEA-S NGF NT-3 NT-4 Antagonists: ALE-0540 Dexamethasone EVT-901 (SAR-127963) Testosterone Antibodies: Against NGF: ABT-110 (PG110) ASP-6294 Fasinumab Frunevetmab Fulranumab MEDI-578 Ranevetmab Tanezumab Aptamers: Against NGF: RBM-004 Decoy receptors: LEVI-04 (p75NTR-Fc) PDGF Agonists: Becaplermin Platelet-derived growth factor (A, B, C, D) Kinase inhibitors: Agerafenib Avapritinib Axitinib Crenolanib Imatinib Lenvatinib Masitinib Motesanib Nintedanib Pazopanib Radotinib Quizartinib Ripretinib Sunitinib Sorafenib Toceranib Antibodies: Olaratumab Ramucirumab Tovetumab RET (GFL) GFRα1 Agonists: Glial cell line-derived neurotrophic factor (GDNF) Liatermin Kinase inhibitors: Vandetanib GFRα2 Agonists: Neurturin (NRTN) Kinase inhibitors: Vandetanib GFRα3 Agonists: Artemin (ARTN) Kinase inhibitors: Vandetanib GFRα4 Agonists: Persephin (PSPN) Kinase inhibitors: Vandetanib Unsorted Kinase inhibitors: Agerafenib SCF (c-Kit) Agonists: Ancestim Stem cell factor Kinase inhibitors: Agerafenib Axitinib Dasatinib Imatinib Masitinib Nilotinib Pazopanib Quizartinib Sorafenib Sunitinib Toceranib TGFβ See here instead. Trk TrkA Agonists: Amitriptyline BNN-20 BNN-27 Cenegermin DHEA DHEA-S Gambogic amide NGF Tavilermide Antagonists: ALE-0540 Dexamethasone FX007 Testosterone Positive allosteric modulators: AC26845 (AC‑0026845) ACD856 ACD857 E2511 Ponazuril (ACD855) Toltrazuril Negative allosteric modulators: VM-902A Kinase inhibitors: Altiratinib AZD-6918 CE-245677 CH-7057288 DS-6051 Entrectinib GZ-389988 K252a Larotrectinib Lestaurtinib Milciclib ONO-4474 ONO-5390556 PLX-7486 Rebastinib SNA-120 (pegylated K252a)) Antibodies: Against TrkA: GBR-900; Against NGF: ABT-110 (PG110) ASP-6294 Fasinumab Frunevetmab Fulranumab MEDI-578 Ranevetmab Tanezumab Aptamers: Against NGF: RBM-004 Decoy receptors: ReN-1820 (TrkAd5) TrkB Agonists: 3,7-DHF 3,7,8,2'-THF 4'-DMA-7,8-DHF 7,3'-DHF 7,8-DHF 7,8,2'-THF 7,8,3'-THF Amitriptyline Braegen-02 BDNF BNN-20 Deoxygedunin Diosmetin DMAQ-B1 HIOC LM22A-4 N-Acetylserotonin NT-3 NT-4 Norwogonin (5,7,8-THF) R7 R13 (BrAD-R13, Braegen-01) SPV-400 TDP6 Antagonists: ANA-12 Cyclotraxin B Gossypetin (3,5,7,8,3',4'-HHF) Ligands: DHEA Positive allosteric modulators: AC26845 (AC‑0026845) ACD856 ACD857 Ponazuril (ACD855) Toltrazuril Kinase inhibitors: Altiratinib AZD-6918 CE-245677 CH-7057288 DS-6051 Entrectinib GZ-389988 K252a Larotrectinib Lestaurtinib ONO-4474 ONO-5390556 PLX-7486 TrkC Agonists: BNN-20 DHEA NT-3 Positive allosteric modulators: AC26845 (AC‑0026845) ACD856 Kinase inhibitors: Altiratinib AZD-6918 CE-245677 CH-7057288 DS-6051 Entrectinib GZ-389988 K252a Larotrectinib Lestaurtinib ONO-4474 ONO-5390556 PLX-7486 VEGF Agonists: Placental growth factor (PGF) Ripretinib Telbermin VEGF (A, B, C, D (FIGF)) Allosteric modulators: Cyclotraxin B Kinase inhibitors: Agerafenib Altiratinib Axitinib Cabozantinib Cediranib Fruquintinib Lapatinib Lenvatinib Motesanib Nintedanib Pazopanib Pegaptanib Rebastinib Regorafenib Semaxanib Sorafenib Sunitinib Toceranib Tivozanib Vandetanib WHI-P 154 Antibodies: Alacizumab pegol Bevacizumab Icrucumab Ramucirumab Ranibizumab Decoy receptors: Aflibercept Others Additional growth factors: Adrenomedullin Colony-stimulating factors (see here instead) Connective tissue growth factor (CTGF) Ephrins (A1, A2, A3, A4, A5, B1, B2, B3) Erythropoietin (see here instead) Glucose-6-phosphate isomerase (GPI; PGI, PHI, AMF) Glia maturation factor (GMF) Hepatoma-derived growth factor (HDGF) Interleukins/T-cell growth factors (see here instead) Leukemia inhibitory factor (LIF) Macrophage-stimulating protein (MSP; HLP, HGFLP) Midkine (NEGF2) Migration-stimulating factor (MSF; PRG4) Oncomodulin Pituitary adenylate cyclase-activating peptide (PACAP) Pleiotrophin Renalase Thrombopoietin (see here instead) Wnt signaling proteins Additional growth factor receptor modulators: Cerebrolysin (neurotrophin mixture)

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