title: Effects of differentiation on purinergic and neurotensin-mediated calcium signaling in human HT-29 colon cancer cells.
abstract: Calcium signaling is a key regulator of processes important in differentiation. In colon cancer cells differentiation is associated with altered expression of specific isoforms of calcium pumps of the endoplasmic reticulum and the plasma membrane, suggesting that differentiation of colon cancer cells is associated with a major remodeling of calcium homeostasis. Purinergic and neurotensin receptor activation are known regulators of cytosolic free Ca(2+) levels in colon cancer cells. This study aimed to assess changes in cytosolic free Ca(2+) levels in response to ATP and neurotensin with differentiation induced by sodium butyrate or culturing post-confluence. Parameters assessed included peak cytosolic free Ca(2+) level after activation; time to reach peak cytosolic free Ca(2+) and the EC50 of dose response curves. Our results demonstrate that differentiation of HT-29 colon cancer cells is associated with a remodeling of both ATP and neurotensin mediated Ca(2+) signaling. Neurotensin-mediated calcium signaling appeared more sensitive to differentiation than ATP-mediated Ca(2+) signaling.
authors: School of Pharmacy, The University of Queensland, Queensland 4072, Australia.
authors: Mohammad A
authors: MA
authors: Chowdhury
authors: Amelia A
authors: AA
authors: Peters
authors: Sarah J
authors: SJ
authors: Roberts-Thomson
authors: Gregory R
authors: GR
authors: Monteith
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D002087:Butyrates / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D020013:Calcium Signaling / Q000187:drug effects*; D002454:Cell Differentiation; D003110:Colonic Neoplasms / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D015972:Gene Expression Regulation, Neoplastic; D019073:HT29 Cells; D006801:Humans; D009496:Neurotensin / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D018028:Receptors, Neurotensin / Q000378:metabolism*; D011983:Receptors, Purinergic / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D002087:Butyrates; D012333:RNA, Messenger; D018028:Receptors, Neurotensin; D011983:Receptors, Purinergic; D009496:Neurotensin; D000255:Adenosine Triphosphate; D002118:Calcium
keywords: ALPI; ATP; Calcium signaling; Colon cancer; Differentiation; ER; FBS; G-protein-coupled receptors; GPCRs; NT; NTS1; NTS2; NTS3; NaBt; Neurotensin receptors; Purinergic receptors; adenosine triphosphate; endoplasmic reticulum; fetal bovine serum; intestinal alkaline phosphatase; neurotensin; neurotensin receptor 1; neurotensin receptor 2; neurotensin receptor 3; sodium butyrate