TY - JOUR
T1 - Plasminogen-induced aggregation of PANC-1 cells requires conversion to plasmin and is inhibited by endogenous plasminogen activator inhibitor-1
AU - Deshet, Naamit
AU - Lupu-Meiri, Monica
AU - Espinoza, Ingrid
AU - Fili, Oded
AU - Shapira, Yuval
AU - Lupu, Ruth
AU - Gershengorn, Marvin C.
AU - Oron, Yoram
PY - 2008/9
Y1 - 2008/9
N2 - PANC-1 cells express proteinase-activated receptors (PARs)-1, -2, and respond to their activation by transient elevation of cytosolic [Ca 2+] and accelerated aggregation (Wei et al., 2006, J Cell Physiol 206:322-328). We studied the effect of plasminogen (PGN), an inactive precursor of the PAR-1-activating protease, plasmin (PN) on aggregation of pancreatic adenocarcinoma (PDAC) cells. A single dose of PGN time- and dose-dependently promoted PANC-1 cells aggregation in serum-free medium, while PN did not. PANC-1 cells express urokinase plasminogen activator (uPA), which continuously converted PGN to PN. This activity and PGN-induced aggregation were inhibited by the uPA inhibitor amiloride. PGN-induced aggregation was also inhibited by α-antiplasmin and by the PN inhibitor ε-aminocaproic acid (EACA). Direct assay of uPA activity revealed very low rate, markedly enhanced in the presence of PGN. Moreover, in PGN activator inhibitor 1-deficient PANC-1 cells, uPA activity and PGN-induced aggregation were markedly potentiated. Two additional human PDAC cell lines, MiaPaCa and Colo347, were assayed for PGN-induced aggregation. Both cell lines responded by aggregation and exhibited PGN-enhanced uPA activity. We hypothesized that the continuous conversion of PGN to PN by endogenous uPA is limited by PN's degradation and negatively controlled by endogenously produced PAI-1. Indeed, we found that PANC-1 cells inactivate PN with t1/2 of approximately 7 h, while the continuous addition of PN promoted aggregation. Our data suggest that PANC-1 cells possess intrinsic, PAI-1-sensitive mechanism for promotion of aggregation and differentiation by prolonged exposure to PGN and, possibly, additional precursors of PARs agonists.
AB - PANC-1 cells express proteinase-activated receptors (PARs)-1, -2, and respond to their activation by transient elevation of cytosolic [Ca 2+] and accelerated aggregation (Wei et al., 2006, J Cell Physiol 206:322-328). We studied the effect of plasminogen (PGN), an inactive precursor of the PAR-1-activating protease, plasmin (PN) on aggregation of pancreatic adenocarcinoma (PDAC) cells. A single dose of PGN time- and dose-dependently promoted PANC-1 cells aggregation in serum-free medium, while PN did not. PANC-1 cells express urokinase plasminogen activator (uPA), which continuously converted PGN to PN. This activity and PGN-induced aggregation were inhibited by the uPA inhibitor amiloride. PGN-induced aggregation was also inhibited by α-antiplasmin and by the PN inhibitor ε-aminocaproic acid (EACA). Direct assay of uPA activity revealed very low rate, markedly enhanced in the presence of PGN. Moreover, in PGN activator inhibitor 1-deficient PANC-1 cells, uPA activity and PGN-induced aggregation were markedly potentiated. Two additional human PDAC cell lines, MiaPaCa and Colo347, were assayed for PGN-induced aggregation. Both cell lines responded by aggregation and exhibited PGN-enhanced uPA activity. We hypothesized that the continuous conversion of PGN to PN by endogenous uPA is limited by PN's degradation and negatively controlled by endogenously produced PAI-1. Indeed, we found that PANC-1 cells inactivate PN with t1/2 of approximately 7 h, while the continuous addition of PN promoted aggregation. Our data suggest that PANC-1 cells possess intrinsic, PAI-1-sensitive mechanism for promotion of aggregation and differentiation by prolonged exposure to PGN and, possibly, additional precursors of PARs agonists.
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U2 - 10.1002/jcp.21441
DO - 10.1002/jcp.21441
M3 - Article
C2 - 18366077
AN - SCOPUS:48749126093
SN - 0021-9541
VL - 216
SP - 632
EP - 639
JO - Journal of Cellular Physiology
JF - Journal of Cellular Physiology
IS - 3
ER -