Azacitidine Plus Phenylbutyrate in Treating Patients With Advanced or Metastatic Solid Tumors That Have Not Responded to Previous Treatment

RATIONALE: Drugs used in chemotherapy use different ways to stop tumor cells from dividing so they stop growing or die. Combining more than one drug may kill more tumor cells. PURPOSE: This phase I trial is studying the side effects and best dose of azacitidine plus phenylbutyrate in treating patients with advanced or metastatic solid tumors that have not responded to previous treatment.

OBJECTIVES: * Evaluate the safety and toxicity of azacitidine plus phenylbutyrate in patients with refractory solid tumors. * Determine the maximum tolerated dose of this treatment regimen where maximal gene reexpression occurs in these patients. * Evaluate the pharmacokinetics of these drugs in these patients. * Determine the minimally effective dose of azacitidine in combination with phenylbutyrate that elicits a biological or clinical response in these patients. OUTLINE: This is a dose escalation study. Patients receive azacitidine subcutaneously for 14-21 days and sodium phenylbutyrate IV continuously for 1-7 days. Treatment repeats every 35 days in the absence of disease progression or unacceptable toxicity. Cohorts of 3-6 patients receive escalating doses and durations of treatment with azacitidine and phenylbutyrate until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose preceding that at which 2 of 6 patients experience dose limiting toxicities. PROJECTED ACCRUAL: Approximately 3-50 patients will be accrued for this study within 12-18 months.