Research output: Contribution to journal › Journal article › Research › peer-review
We have studied the effect of the tumor promotor phorbol myristate acetate (PMA) on the level of mRNA for the receptor for urokinase-type plasminogen activator (u-PAR) in the human monocyte-like cell line U937. PMA causes an early increase in the u-PAR mRNA level which reaches a maximal 50-fold enhancement after 24 h of treatment. Half-maximal stimulation occurs at approximately 5 nM PMA. The effect is observed only with phorbol esters that also act as tumor promotors. The protein synthesis inhibitor cycloheximide (10 micrograms/ml) also increases the level of u-PAR mRNA. Nuclear run-on experiments show a time-dependent increase in the u-PAR gene transcription rate after exposure of the cells to PMA. The PMA-induced increase in u-PAR mRNA is paralleled by a time-dependent increase in u-PAR protein as detected by cross-linking studies with radiolabeled ligand. We conclude that PMA stimulates transcription of the u-PAR gene in U937 cells, and this is responsible at least in part for the accumulation of the u-PAR mRNA and for the subsequent increase in urokinase-binding capacity.
Original language | English |
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Journal | The journal of biological chemistry |
Volume | 266 |
Issue number | 8 |
Pages (from-to) | 5177-81 |
Number of pages | 5 |
ISSN | 0021-9258 |
Publication status | Published - 15 Mar 1991 |
ID: 46434653