Experiment
| AccNo. |
45058 |
Classification incorrect?
Click the corresponding button to vote. Your vote
is used to improve the automatic classification.
|
| CA |
CVD |
DM |
APO |
ANG |
MI |
BD |
|
| 0.78 |
0.81 |
0.38 |
0.79 |
0.23 |
0.33 |
0.51 |
Vote |
 |
 |
 |
 |
 |
 |
 |
Yes |
 |
 |
 |
 |
 |
 |
 |
No |
|
| Name |
PM_11160861 |
| Detection |
unspecified method, MI:0686 |
| Source |
Pubmed |
Text Id |
11160861 |
| Journal |
Mol Pharmacol. 2001 Feb;59(2):254-62. |
| Title |
Involvement of Asp-Glu-Val-Asp-directed, caspase-mediated mitogen-activated protein kinase kinase 1 Cleavage, c-Jun N-terminal kinase activation, and subsequent Bcl-2 phosphorylation for paclitaxel-induced apoptosis in HL-60 cells. |
| Authors |
Shiah SG, Chuang SE, Kuo ML |
| Text |
Paclitaxel is a novel anticancer drug that has demonstrated efficacy toward treating several malignant tumor types. Here, we demonstrate that c-Jun NH(2)-terminal kinase (JNK), but not p38 mitogen-activated protein kinase or extracellular signal-regulated kinase 1/2, was persistently activated by paclitaxel or other microtubule-damaging agents within human leukemia HL-60 cells. Overexpression of a dominant-negative mutant, mitogen-activated protein kinase kinase 1 (MEKK1-DN) or treatment with JNK-specific antisense oligonucleotide prevented paclitaxel-induced JNK activation, Bcl-2 phosphorylation and apoptosis. Furthermore, we found that the full-length MEKK1 was cleaved to a 91-kDa carboxyl-terminal fragment at the earlier time of apoptosis induced by microtubule-damaging agents. This cleavage, however, occurred consistently with JNK activation and Bcl-2 phosphorylation, but preceded DNA fragmentation in cells in response to paclitaxel activity. The caspase inhibitor Ac-Asp-Glu-Val-Asp-CHO (DEVD-CHO), but not Ac-Tyr-Val-Ala-Asp-CHO (Ac-YVAD-CHO), effectively blocked MEKK1 cleavage, JNK activation, Bcl-2 phosphorylation, and subsequent apoptosis. Subcellular fractionation revealed that the 91-kDa C-terminal MEKK1 fragment was translocated to cytosol. Notably, the MEKK1 fragment could be coimmunoprecipitated with anti-JNK antibodies, suggesting that a signaling complex of C-terminal MEKK1/stress-activated protein kinase/extracellular-signal regulated kinase 1/JNK formed during apoptosis induced by microtubule-damaging agents. Taken together, our results suggest that disruption of cytoarchitecture by paclitaxel triggers a novel apoptosis-signaling pathway, wherein an active DEVD-directed caspase (DEVDase) initially cleaves MEKK1to generate a proapoptotic kinase fragment that is able to activate JNK and subsequent Bcl-2 phosphorylation, finally eliciting cell death. |
| Mesh Terms |
Antineoplastic Agents, Phytogenic/pharmacology; Apoptosis; Caspases/metabolism; Cell Cycle/drug effects; Cysteine Proteinase Inhibitors/pharmacology; Enzyme Activation/drug effects; HL-60 Cells; Humans; JNK Mitogen-Activated Protein Kinases; MAP Kinase Kinase Kinase 1; Mitogen-Activated Protein Kinases/metabolism; Oligopeptides/pharmacology; Paclitaxel/pharmacology; Peptide Fragments/metabolism; Peptide Hydrolases/physiology; Phosphorylation/drug effects; Protein-Serine-Threonine Kinases/metabolism; Proto-Oncogene Proteins c-bcl-2/metabolism |
|