Journal of neuro-oncology
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Journal of neuro-oncology · Feb 1999
Case ReportsRecurrent chondrosarcoma of the cranial base: a durable response to ifosfamide-doxorubicin chemotherapy.
The case of a 46-year old woman with recurrent chondrosarcoma of the cranial base, refractory to neurosurgical intervention and external radiotherapy is reported. She received five cycles of systemic chemotherapy utilizing ifosfamide and doxorubicin which resulted in a durable clinical and radiographic response lasting 52+ months. A review of the management options for recurrent chondrosarcoma of the cranial base is also presented.
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Journal of neuro-oncology · Feb 1999
Synergistic cytotoxicity, apoptosis and protein-linked DNA breakage by etoposide and camptothecin in human U87 glioma cells: dependence on tyrosine phosphorylation.
In this study, simultaneous administration of certain inhibitors of topoisomerase I and topoisomerase II produced synergistic cytotoxicity in a series of human glioma cell lines. Camptothecin (CPT) and etoposide (VP-16) produced combination indices (CI) <1.0 in all glioma cell lines tested, including those that were relatively resistant to the two topoisomerase inhibitors individually. In contrast, CPT and VP-16 produced additive cytotoxicity in HT-29 and SW-620 colon carcinoma cell lines. ⋯ CPT and VP-16 also produced a synergistic accumulation of sub-G0 (apoptotic) cells which was blocked by tyrphostin-A23. No significant increase in topoisomerase protein levels could be detected in response to combination treatment. Thus, synergistic effects between topoisomerase I and topoisomerase II inhibitors in U87 glioma cells may depend upon phosphorylation of cellular proteins other than the topoisomerases themselves.