Table 1 Examples of direct and indirect mechanisms, factors affecting the radius and the cost.

From: Signalling architectures can prevent cancer evolution

Type of signallingSenderEffectorRadiusCost
Extracellular changesIntracellular changes
DirectIWnt, HhWnt[*] : lipoprotein particles28. Heparin30, Heparan sulfate (HSPGs)31,32,33, SFRPs and WIFs34,35,36,37,38,39,40. Hh[*] : Dispatched21Wnt [1, 2]: APC gene41. Hh1 :42.Production Cost
 IIProstaglandinsProstaglandins[*] : Kruppel-like factor (KLF)43.Prostaglandins[2]43.Production Cost. ATP-dependent exporter44.
IndirectIVEGF, FGFO2, nutrients, EGE, TGF-βVEGF[*]: Physical forces22. FGF[*] : Heparan sulfate23.VEGF [1]: EGF receptors27,45. TGF-β2 : ras, myc and fos genes. FGF1 :23. Production Cost
 IIPDGF, TGF-βIGF, HGFTGF-β[*]: Activin24. HGF[*]: heparin and heparin sulphate46,47.PDGF[2] : ras, myc and fos genes48,49,50.Production Cost
  1. *Post-translational modifications and association with extracellular vehicles.
  2. 1Modifications in receptor number and/or affinity or 2modifications resulting in processes that amplify the mitogenic signal after its interaction with the receptor.