5-lipoxygenase regulates malignant mesothelial cell survival: involvement of vascular endothelial growth factor.
Evidence indicates that lipoxygenases (LO) may play a role in cancer cell survival. We show that human malignant pleural mesothelial (MM) cells, but not normal mesothelial (NM) cells, express a catalytically active 5-LO. Pharmacological or genetic inhibition of MM cell 5-LO determined nucleosome formation and induced a DNA fragmentation pattern typical of apoptosis. This was completely reversed by exogenously added 5(S)-HETE but not by 12(S)-, 15(S)-HETE, or leukotriene (LT)B4. A 5-LO antisense oligonucleotide potently and time-dependently reduced vascular endothelial growth factor (VEGF) mRNA and constitutive VEGF accumulation in the conditioned media of MM cells. When NM cells were transfected with a 5-LO cDNA, basal and arachidonic acid-induced VEGF formation increased consistently by 6- and 12-fold, respectively. This was associated with a significant increase in DNA synthesis that was counteracted by a specific anti-VEGF antibody. Arachidonic acid and 5(S)-HETE also potently stimulated the activity of a VEGF promoter construct. Thus, 5-LO is a key regulator of MM cell proliferation and survival via a VEGF-related circuit.
Romano
M
M
Department of Human Pathology, University of Messina, Messina, Italy. mromano@unich.it
Catalano
A
A
Nutini
M
M
D'Urbano
E
E
Crescenzi
C
C
Claria
J
J
Libner
R
R
Davi
G
G
Procopio
A
A
D017209:Apoptosis / Q000187:drug effects / Q000502:physiology; D001094:Arachidonate 5-Lipoxygenase / Q000235:genetics / Q000378:metabolism*; D016718:Arachidonic Acid / Q000494:pharmacology; D016227:Benzoquinones / Q000494:pharmacology; D002455:Cell Division / Q000187:drug effects / Q000502:physiology; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology*; D016373:DNA, Antisense / Q000235:genetics / Q000494:pharmacology; D016228:Endothelial Growth Factors / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation; D015971:Gene Expression Regulation, Enzymologic; D049452:Green Fluorescent Proteins; D006801:Humans; D016859:Lipoxygenase Inhibitors / Q000494:pharmacology; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008222:Lymphokines / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D009637:Masoprocol / Q000494:pharmacology; D008654:Mesothelioma / Q000201:enzymology / Q000473:pathology*; D009154:Mutation; D011401:Promoter Regions, Genetic / Q000235:genetics; D012313:RNA / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013936:Thymidine / Q000378:metabolism; D013997:Time Factors; D014158:Transcription, Genetic; D014162:Transfection; D014316:Tritium; D014407:Tumor Cells, Cultured; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
D016227:Benzoquinones; D016373:DNA, Antisense; D016228:Endothelial Growth Factors; D016859:Lipoxygenase Inhibitors; D008164:Luminescent Proteins; D008222:Lymphokines; D011993:Recombinant Fusion Proteins; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D014316:Tritium; D049452:Green Fluorescent Proteins; D016718:Arachidonic Acid; D012313:RNA; D009637:Masoprocol; C036837:2,3,5-trimethyl-6-(12-hydroxy-5,10-dodecadiynyl)-1,4-benzoquinone; D001094:Arachidonate 5-Lipoxygenase; D013936:Thymidine