Fig. 1
Neurotransmitters signalling pathways in cancer. Cancer neuro-immune communication is through the release of neurotransmitters using different signalling kinases which promote cancer progression via metastasis. Perineural invasion mediate cancer metastasis through the release of the NGF and GDNF via the activation of different signaling pathway. Ach, acetylcholine; β2-AR, β2-adrenergic receptor;cAMP, cyclic adenosine monophosphate; DA, dopamine; DR, dopamine receptor; EGFR, epidermal growth factor receptor;EMT,epithelial–mesenchymal transition; ERK1/2, extracellular signal-regulated kinase;FAK, focal adhesion kinase; GABA, gamma-aminobutyric acid; GABAB,gamma-aminobutyric acid receptorB;GDNF, glial cell line-derived neurotrophic factor; GFRα, glial cell line-derived neurotrophic factor receptor 1;ICAM-1, intercellular adhesion molecule-1; JAK2,janus kinase 2;MEK, MAPK/ERK kinase;mTOR, mammalian/mechanistic target of rapamycin;MMP, matrix metallopeptidase;MAPK,mitogen-activated protein kinases;RAF, mitogen activated protein kinase;RAS, mitogen activated protein kinase;mAChRs, muscarinic acetylcholine receptors;NK-1R, neurokinin-1 receptor; NGF, nerve growth factor;nAChR, nicotinic acetylcholine receptor;NE, norepinephrine;NF-kB, nuclear factor-kappa B;PLC, phospholipase C; PI3K, phosphoinositide 3-kinase;PKA, protein kinase A;PKC, protein kinase C;RET, proto-oncogene;AKT, serine/threonine kinase or protein kinase B;STAT3,signal transducer and activator of transcription 3; SP,substance P;TrkA,tropomyosin related kinase A