Cleaved intracellular plasminogen activator inhibitor 2 in human myeloleukaemia cells is a marker of apoptosis.
The proteolytic modification of plasminogen activator inhibitor 2 (PAI-2) was studied during apoptosis in the human promyelocytic leukaemic NB4 cell line during treatment with the phosphatase inhibitors okadaic acid and calyculin A as well as the protein synthesis inhibitor cycloheximide. The apoptic type of cell death was ascertained by morphological and biochemical criteria. In cell homogenates PAI-2 was probed by [125I]urokinase plasminogen activator (uPA) and detected as a sodium dodecyl sulphate-stable M(r) 80,000 complex after reducing sodium dodecyl sulphate-polyacrylamide gel electrophoresis and autoradiography. During apoptosis a smaller (M(r) 70,000) uPA-PAI-2 complex was consistently detected. The modification was in the PAI-2 moiety, as the [125I]uPA tracer could be extracted in its intact form from the complex. Thus the cleaved PAI-2 isoform is a biochemical marker of apoptosis in the promyelocytic NB4 cell line. The modified PAI-2 isoform was also detected in homogenates made from purified human mononuclear leukaemic cells aspirated from the bone marrow of patients suffering from acute and chronic myeloid leukaemia.
Jensen
P H
PH
Department of Medical Biochemistry, Aarhus University, Denmark.
Cressey
L I
LI
Gjertsen
B T
BT
Madsen
P
P
Mellgren
G
G
Hokland
P
P
Gliemann
J
J
Døskeland
S O
SO
Lanotte
M
M
Vintermyr
O K
OK
D017209:Apoptosis / Q000502:physiology*; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001853:Bone Marrow / Q000378:metabolism; D016923:Cell Death / Q000502:physiology; D004988:Ethers, Cyclic / Q000494:pharmacology; D006801:Humans; D007424:Intracellular Fluid / Q000378:metabolism; D007536:Isomerism; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000378:metabolism* / Q000473:pathology*; D015473:Leukemia, Promyelocytic, Acute / Q000378:metabolism* / Q000473:pathology*; D008387:Marine Toxins; D019319:Okadaic Acid; D010080:Oxazoles / Q000494:pharmacology; D010749:Phosphoprotein Phosphatases / Q000037:antagonists & inhibitors; D017396:Plasminogen Activator Inhibitor 2 / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D014408:Biomarkers, Tumor; D004988:Ethers, Cyclic; D008387:Marine Toxins; D010080:Oxazoles; D017396:Plasminogen Activator Inhibitor 2; D019319:Okadaic Acid; C059041:calyculin A; D010749:Phosphoprotein Phosphatases