title: A pharmacological analysis of the cholinergic regulation of urokinase-type plasminogen activator secretion in the human colon cancer cell line, HT-29.
abstract: Urokinase-type plasminogen activator (uPA) is an important factor for tumour cell invasion and metastasis. We recently showed that acetylcholine is an autocrine/paracrine growth factor for the human colon cancer cell line, HT-29, in part via the α7 subtype of the nicotinic acetylcholine receptors. In the current study, we investigated whether acetylcholine participates in the regulation of the protein expressions of also uPA and its receptor (uPAR) in the HT-29 cell line. Such were investigated by immunocytochemistry and Western blotting, and quantitation of uPA secretion was undertaken by ELISA. Stimulation of the cells for 24h with nicotine caused increased uPA secretion with peak effect (78% above the control) occurring at a nicotine concentration of 10nM. This effect was markedly inhibited by α-Bungarotoxin, thus showing the involvement of α7 nicotinic acetylcholine receptors. Basal uPA secretion was found to be partly dependent on ongoing activation of nicotinic receptors, suggesting tonic production of acetylcholine. Conversely, there was no cholinergic influence on the expression of uPAR. The current findings demonstrate novel aspects of receptor-mediated regulation of tumour metastatic potential via uPA secretion. This may suggest future pharmaceutical strategies in treatment of colorectal cancer.
authors: Department of Surgery, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
authors: Ann
authors: A
authors: Novotny
authors: Karin
authors: K
authors: Edsparr
authors: Gunnar
authors: G
authors: Nylund
authors: Amir
authors: A
authors: Khorram-Manesh
authors: Per
authors: P
authors: Albertsson
authors: Svante
authors: S
authors: Nordgren
authors: Dick S
authors: DS
authors: Delbro
mesh_terms: D000109:Acetylcholine / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects; D018678:Cholinergic Agents / Q000494:pharmacology*; D003110:Colonic Neoplasms / Q000473:pathology*; D004305:Dose-Response Relationship, Drug; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D019073:HT29 Cells; D006801:Humans; D009538:Nicotine / Q000494:pharmacology; D011978:Receptors, Nicotinic / Q000378:metabolism; D055293:Receptors, Urokinase Plasminogen Activator / Q000378:metabolism; D014568:Urokinase-Type Plasminogen Activator / Q000378:metabolism*; D064569:alpha7 Nicotinic Acetylcholine Receptor
chemical_list: D018678:Cholinergic Agents; C579167:Chrna7 protein, human; D011978:Receptors, Nicotinic; D055293:Receptors, Urokinase Plasminogen Activator; D064569:alpha7 Nicotinic Acetylcholine Receptor; D009538:Nicotine; D014568:Urokinase-Type Plasminogen Activator; D000109:Acetylcholine