SB939 in Treating Patients With Recurrent or Metastatic Prostate Cancer

DISEASE CHARACTERISTICS: * Histologically confirmed adenocarcinoma of the prostate * Presence of clinically and/or radiologically documented disease (target or non-target) * Metastatic or locally recurrent disease for which no curative therapy exists AND for which systemic chemotherapy is indicated due to progression, meeting the following criteria: * At least two rises in PSA over a reference value OR the development of new metastatic lesions with a stable or rising PSA * First rising PSA must be taken at least 1 week after the reference value * Third or subsequent PSA must show further increase confirming progression within 2 weeks prior to study enrollment * PSA progression must be documented after discontinuation of peripheral antiandrogens (4 weeks for flutamide and 6 weeks for bicalutamide/nilutamide) for patients with documented evidence of progression while receiving peripheral antiandrogens * Medically or surgically castrated by androgen ablation * Castrate level of testosterone (\< 1.7 nmol/L) must be present for patients undergoing medical androgen ablation * Received prior hormone therapy * Must have hormone-refractory disease * Therapy with luteinizing hormone-releasing hormone (LHRH) agonist must continue for patients already receiving this treatment at the time of enrollment * Patients who discontinued LHRH agonist must restart therapy (if not surgically castrated) and the castrate level of testosterone must be present * PSA ≥ 5 ng/mL * Primary or metastatic tumor tissue available * No documented CNS metastases PATIENT CHARACTERISTICS: * ECOG performance status 0-1 * Life expectancy ≥ 12 weeks * Absolute granulocyte count ≥ 1.5 x 10\^9/L * Platelet count ≥ 100 x 10\^9/L * AST and ALT ≤ 2.5 times upper limit of normal (ULN) * Bilirubin normal * Serum creatinine normal * Potassium normal * Calcium normal * Fertile patients must use effective contraception * QTc ≤ 450 msec * LVEF ≥ 50% by Echo or MUGA scan * Troponin I or T ≤ ULN * Able to take oral medication * No preexisting uncontrolled cardiac condition * No prior myocardial infarction * No history of other malignancies, except adequately treated nonmelanoma skin cancer or other solid tumors curatively treated with no evidence of disease for ≥ 5 years * No gastrointestinal abnormalities (e.g., bowel obstruction or previous gastric resection) that would lead to inadequate absorption of HDAC Inhibitor SB939 * No known HIV positivity or hepatitis B or C infections * No chronic medical condition or comorbidity that may increase the risks associated with study participation/study drug administration or may interfere with the interpretation of study results, including any of the following: * Pulmonary disease * Active infection * Psychiatric condition * Laboratory abnormality PRIOR CONCURRENT THERAPY: * See Disease Characteristics * At least 4 weeks since prior antiandrogens (6 weeks for bicalutamide) * At least 4 weeks since prior external-beam radiotherapy * Exceptions may be made for low-dose, non-myelosuppressive radiotherapy * At least 28 days since other prior investigational therapy or anticancer therapy * At least 14 days since prior major surgery and wound healing has occurred * No more than 1 prior chemotherapy regimen allowed and recovered from significant toxicity * No prior strontium * No prior HDAC inhibitors * No current agents (dysrhythmic drugs) with a known risk of Torsades de Pointes * No other concurrent cytotoxic therapy or radiotherapy * No other concurrent investigational therapy