Epidermal growth factor induces p11 gene and protein expression and down-regulates calcium ionophore-induced arachidonic acid release in human epithelial cells.
p11, a member of the S-100 family of proteins, is the cellular ligand of annexin II and also interacts with the C-terminal region of cytosolic phospholipase A(2) (cPLA(2)), inhibiting cPLA(2) activity and arachidonic acid (AA) release. It has been reported that epidermal growth factor (EGF) induces cPLA(2) activation or cPLA(2) expression and subsequent AA release. It was of interest to study the effect of EGF on p11 production and on AA release in human epithelial cells (HeLa). EGF (20 ng/ml) treatment of HeLa cells increased the cellular p11 protein and the steady-state levels of p11 mRNA in a time- and dose-dependent manner but did not affect cPLA(2) protein expression over a 4-48-h incubation time. Transient transfection experiments of a reporter gene construct containing 1498 bp of the 5'-flanking region of p11 promoter demonstrated that EGF induced p11 gene expression at the transcriptional level. EGF caused a rapid phosphorylation of p44/42 and p38 kinases with a maximum level at 10 min. AG 1478 (EGF receptor tyrosine kinase inhibitor), PD 98059 (ERK1/2 inhibitor), and SB 203580 (p38 inhibitor) significantly inhibited EGF-induced p11 expression. EGF-induced AA release was significantly suppressed by AG 1478, PD 98059, SB 203580, and methyl arachidonyl fluorophosphate (a specific cPLA(2) inhibitor). Methyl arachidonyl fluorophosphate (50 microm) also significantly inhibited EGF-induced p11 expression, demonstrating that the activation of cPLA(2) may have a role in the EGF-induced p11 expression. Immunoprecipitation experiments showed that EGF induced increased p11 binding to cPLA(2) in a time- and dose-dependent manner. EGF treatment for 30 min increased -induced AA release, whereas EGF treatment for 24 h inhibited -induced AA release. These results suggest that EGF treatment increased p11 bound to cPLA(2) may lead to the late suppression of AA release induced by EGF.
Huang
Xiu-Li
XL
Critical Care Medicine Department of the Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, Maryland 20892, USA.
Pawliczak
Rafal
R
Cowan
Mark J
MJ
Gladwin
Mark T
MT
Madara
Patricia
P
Logun
Carolea
C
Shelhamer
James H
JH
D017306:Annexin A2; D016718:Arachidonic Acid / Q000378:metabolism*; D001095:Arachidonic Acids / Q000494:pharmacology; D000001:Calcimycin / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism*; D002135:Calcium-Binding Proteins / Q000235:genetics* / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation / Q000502:physiology; D004791:Enzyme Inhibitors / Q000378:metabolism; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D004847:Epithelial Cells / Q000187:drug effects* / Q000378:metabolism; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D007476:Ionophores / Q000494:pharmacology; D020935:MAP Kinase Signaling System / Q000502:physiology; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D063065:Organophosphonates / Q000494:pharmacology; D010741:Phospholipases A / Q000378:metabolism; D010766:Phosphorylation; D011994:Recombinant Proteins / Q000378:metabolism; D009418:S100 Proteins; D000099248:S100 Calcium Binding Protein A10
D017306:Annexin A2; D016718:Arachidonic Acid; D001095:Arachidonic Acids; D000001:Calcimycin; D002118:Calcium; D002135:Calcium-Binding Proteins; D004791:Enzyme Inhibitors; D004815:Epidermal Growth Factor; D066246:ErbB Receptors; D007476:Ionophores; D020928:Mitogen-Activated Protein Kinases; D063065:Organophosphonates; D010741:Phospholipases A; D011994:Recombinant Proteins; D009418:S100 Proteins; D000099248:S100 Calcium Binding Protein A10; C104810:methyl arachidonylfluorophosphonate