Combined action of the dinuclear platinum compound BBR3610 with the PI3-K inhibitor PX-866 in glioblastoma.

Abstract

Polynuclear platinum compounds are more effective at killing glioblastoma cells than cisplatin, work by a different mechanism, and typically do not induce high levels of apoptosis at early time points after exposure. Here, we tested the hypothesis that combining BBR3610, the most potent polynuclear platinum, with a phosphoinositide-3-kinase (PI3K) inhibitor would promote apoptosis and enhance the impact on glioblastoma cells. The PI3K pathway is commonly activated in glioblastoma and promotes tumor cell survival, suggesting that its inhibition would make cells more sensitive to cytotoxic agents. We chose PX-866 as a PI3K inhibitor as it is a clinically promising agent being evaluated for brain tumor therapy. Combining BBR3610 and PX-866 resulted in synergistic killing of cultured glioma cells and an extension of survival in an orthotopic xenograft animal model. Both agents alone induced autophagy, and this appeared to be saturated, because when they were combined no additional autophagy was observed. However, the combination of PX-866 and BBR3610 did induce statistically significant increases in the level of apoptosis, associated with a reduction in pAkt and pBad, as well as inhibition of transwell migration. We conclude that combining polynuclear platinums with PI3K inhibitors has translational potential and alters the cellular response to include early apoptosis.

• Authors: Ho-Shin Gwak, Takashi Shingu, Vaibhav Chumbalkar, Yeo-Hyeon Hwang, Robert DeJournett, Khatri Latha, Dimpy Koul, W K Alfred Yung, Garth Powis, Nicholas P Farrell, Oliver Bögler
• Journal: International journal of cancer (Int J Cancer) Vol. 128 Issue 4 Pg. 787-96 (Feb 15 2011) ISSN: 1097-0215 [Electronic] United States
• PMID: 20473884 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2010 UICC.

Chemical References

• BBR3610
• Gonanes
• Organoplatinum Compounds
• PX-866
• Phosphoinositide-3 Kinase Inhibitors
• RNA, Messenger
• Proto-Oncogene Proteins c-akt

Topics

• Animals
• Apoptosis (drug effects)
• Autophagy (drug effects)
• Blotting, Western
• Brain Neoplasms (drug therapy, metabolism, pathology)
• Cell Adhesion (drug effects)
• Cell Cycle (drug effects)
• Cell Movement (drug effects)
• Cell Proliferation (drug effects)
• Drug Synergism
• Drug Therapy, Combination
• Glioma (drug therapy, metabolism, pathology)
• Gonanes (therapeutic use)
• Humans
• Male
• Mice
• Mice, Nude
• Organoplatinum Compounds (therapeutic use)
• Phosphoinositide-3 Kinase Inhibitors
• Proto-Oncogene Proteins c-akt
• RNA, Messenger (genetics)
• Reverse Transcriptase Polymerase Chain Reaction
• Signal Transduction (drug effects)
• Survival Rate
• Tumor Cells, Cultured