Format

Send to

Choose Destination
See comment in PubMed Commons below
Mol Cancer Ther. 2003 Jun;2(6):549-55.

Flavopiridol enhances the effect of docetaxel in vitro and in vivo in human gastric cancer cells.

Author information

  • 1Gastrointestinal Oncology Research Laboratory, Division of Solid Tumor Oncology, Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA.

Abstract

Gastric cancer is one of the leading causes of cancer death throughout the world. It is a disease in desperate need of new therapeutic approaches. Docetaxel, a semisynthetic taxane, has shown potent activity against a broad range of solid tumors. However, in gastric cancer, response rates to docetaxel remain only approximately 20%. In these studies we show that flavopiridol, a cyclin-dependent kinase inhibitor, potentiates docetaxel-induced apoptosis 3-fold in MKN-74 human gastric cells. This effect is sequence dependent, such that flavopiridol must follow docetaxel to induce this effect. Docetaxel induces transient arrest in the M phase of the cell cycle. Cells exit mitosis in a specific time window without cytokinesis with a decrease in cyclin B1/cdc-2 kinase activity and MPM-2 labeling. Flavopiridol treatment of docetaxel-treated cells enhances the exit from mitosis with a more rapid decrease in mitotic markers including MPM-2 labeling and cyclin B1/cdc2 kinase activity. In contrast, pretreatment with flavopiridol prevents cells from entering mitosis by inhibiting cyclin B1/cdc-2 kinase activity, thus antagonizing the docetaxel effect. The testing of this combination against MKN-74 xenografts confirms the sequence dependency. Treatment of MKN-74 tumor-bearing xenografts with docetaxel at a dose of 10 mg/kg followed 3-7 h later by flavopiridol at a dose of 2.5 mg/kg resulted in a 1-18% decrease in tumor volume. In contrast, treatment with docetaxel alone at this same dose resulted in a 394% increase in tumor volume. When flavopiridol was given immediately after docetaxel, the effect was not statistically different from that of docetaxel alone. The reverse combination of flavopiridol followed 7 h later by docetaxel was similar to treatment with docetaxel alone. Flavopiridol alone had no effect in this tumor model. Thus, flavopiridol, when combined with docetaxel in a sequence-specific manner, may provide a completely new therapeutic approach in the treatment of gastric cancer.

PMID:
12813134
[PubMed - indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Write to the Help Desk