Bortezomib and Temozolomide in Treating Patients With Brain Tumors or Other Solid Tumors That Have Not Responded to Treatment

OBJECTIVES: Primary * To determine the dose-limiting toxicities and maximum tolerated doses of bortezomib and temozolomide in patients with recurrent high-grade gliomas, recurrent metastatic brain tumors, or other refractory solid tumors. Secondary * To evaluate the pharmacokinetics of bortezomib in patients taking hepatic enzyme-inducing anticonvulsants (Group A) and in those who are not (Group B). * To describe the proportion of study patients treated with bortezomib and temozolomide who obtain a confirmed complete response or partial response. * To report the percentage of patients with 6-month progression-free survival. OUTLINE: Patients are stratified according to concurrent hepatic enzyme-inducing anticonvulsants (HEIAs) (Group A) versus concurrent anticonvulsant drugs that cause modest or no induction of hepatic metabolic enzymes OR no anticonvulsant drugs (Group B). * Group A: Patients receive oral temozolomide once a day on days 1-5 and bortezomib IV on days 2, 5, 9, and 12. Courses repeat every 28 days in the absence of disease progression or unacceptable toxicity. * Group B: Patients receive temozolomide and bortezomib as in group A. Cohorts of patients in both groups receive escalating doses of both study drugs until the maximum tolerated doses are determined. All patients undergo blood sample collection periodically for pharmacokinetic studies. Samples are analyzed for bortezomib concentration (groups A and B) and trough levels of anticonvulsants (group A only).