Decitabine and Bortezomib in Treating Patients With Acute Myeloid Leukemia

Inclusion Criteria: * Diagnosis of acute myeloid leukemia (AML), meeting one of the following criteria: * Relapsed or refractory disease (≥ 18 years of age) * Previously untreated disease (≥ 60 years of age) * Secondary AML or therapy-related AML allowed * No granulocytic sarcoma as the sole site of disease * No active or relapsed CNS disease * No advanced malignant solid tumors * ECOG performance status 0-2 * Life expectancy \> 6 months (if patient has co-morbid illness) * Total bilirubin \< 2.0 mg/dL * AST and ALT \< 2.5 times upper limit of normal * Creatinine \< 2.0 mg/dL * Not pregnant or nursing * Negative pregnancy test * Fertile patients must use effective contraception * Patients with HIV infection are eligible provided the following criteria are met: * No history of AIDS * Has a sufficiently high CD4 count (\> 400/mm³) * Has low HIV viral loads (\< 30,000 copies/mL plasma) * Does not require anti-HIV therapy * No uncontrolled active infection * No history of allergic reactions attributed to compounds of similar chemical or biological composition to decitabine or bortezomib that are not easily managed * No hypersensitivity to boron or mannitol * No concurrent uncontrolled illness including, but not limited to, any of the following: * Symptomatic congestive heart failure * Unstable or uncontrolled angina pectoris * Serious cardiac arrhythmia * Myocardial infarction within the past 6 months * New York Heart Association class III-IV heart failure * Severe uncontrolled ventricular arrhythmias * Acute ischemia or active conduction system abnormalities by ECG * No serious medical or psychiatric illness or social situation that would preclude participation in this study * No pre-existing neuropathy ≥ grade 2 * No other serious neurologic toxicity that would significantly increase the risk of complications from bortezomib therapy * Recovered from prior therapy (toxicity \< grade 2) * More than 14 days since prior investigational agents * More than 2 weeks since prior chemotherapy (6 weeks for nitrosoureas or mitomycin C) or radiotherapy * Prior decitabine or azacitidine for myelodysplastic syndromes (MDS) or AML allowed * More than 6 months since prior decitabine, azacitidine, or bortezomib * No concurrent palliative radiotherapy * No other concurrent investigational agents * No other concurrent direct anti-leukemia therapy