Novel Dual-Reporter Preclinical Screen for Antiastrocytoma Agents Identifies Cytostatic and Cytotoxic Compounds

Mouse Cancer Genetics Program, National Cancer Institute, Frederick, Maryland 21702, USA.
Journal of Biomolecular Screening (Impact Factor: 2.42). 08/2008; 13(8):795-803. DOI: 10.1177/1087057108321085
Source: PubMed


Astrocytoma/glioblastoma is the most common malignant form of brain cancer and is often unresponsive to current pharmacological therapies and surgical interventions. Despite several potential therapeutic agents against astrocytoma and glioblastoma, there are currently no effective therapies for astrocytoma, creating a great need for the identification of effective antitumor agents. The authors have developed a novel dual-reporter system in Trp53/Nf1-null astrocytoma cells to simultaneously and rapidly assay cell viability and cell cycle progression as evidenced by activity of the human E2F1 promoter in vitro. The dual-reporter high-throughput assay was used to screen experimental therapeutics for activity in Trp53/Nf1-null astrocytoma. Several compounds were identified demonstrating selectivity for astrocytoma over primary astrocytes. The dual-reporter system described here may be a valuable tool for identifying potential antitumor treatments that specifically target astrocytoma.

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    • "After attachment (!4 h), extracts, fractions, or pure compounds were added and red and green luminescence assessed using Promega ChromoGlo reagent 2 d later. Inhibition of the green luminescence signal (E2F1) reflects growth inhibition while inhibition of the red signal (CMV) indicates loss of cell viability (Hawes et al., 2008). "
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    • "Owing to simultaneous detection of two different reporters, this system is able to distinguish cytotoxic compounds from cytostatic compounds in a single assay. This system can also be used to examine the pharmacology of antitumor agents and combinatorial treatments in a high-throughput manner in Nf1- null;Trp53-null astrocytoma cells, and then positive hits can be screened against a wider range of human and mouse astrocytoma cell lines (Hawes et al. 2008) and in vivo systems. The G/R-luc dual-reporter system will likely be a valuable tool in the identification and characterization of potential antitumor agents specifically targeting astrocytoma and Nf1-null;Trp53- null tumors. "
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