Sensitivity to cisplatin in primary cell lines derived from human glioma correlates with levels of EGR-1 expression.

Background: Less than 30% of malignant gliomas respond to adjuvant chemotherapy. Here, we have asked whether variations in the constitutive expression of early-growth response factor 1 (EGR-1) predicted acute cytotoxicity and clonogenic cell death in vitro, induced by six different chemotherapics. Materials and methods: Cytotoxicity assays were performed on cells derived from fresh tumor explants of 18 human cases of malignant glioma. In addition to EGR-1, tumor cultures were investigated for genetic alterations and the expression of cancer regulating factors, related to the p53 pathway. Results: We found that sensitivity to cisplatin correlates significantly with levels of EGR-1 expression in tumors with wild-type p53/INK4a/p16 status. Conclusion: Increased knowledge of the mechanisms regulating EGR-1 expression in wild-type p53/INK4a/p16 cases of glioma may help in the design of new chemotherapeutic strategies for these tumors.