DISEASE CHARACTERISTICS:

• Histologically or cytologically confirmed hepatocellular carcinoma that is not amenable to curative resection
• Measurable disease, defined as ≥ 1 lesion that can be accurately measured in ≥ 1 dimension (longest diameter to be recorded) as ≥ 20 mm with conventional techniques OR as ≥ 10 mm with MRI or spiral CT scan
• No known brain metastases
• No clinical ascites or encephalopathy

PATIENT CHARACTERISTICS:

• Life expectancy > 12 weeks
• ECOG performance status (PS) 0-2 or Karnofsky PS 60-100%
• WBC ≥ 3,000/mm³
• Absolute neutrophil count ≥ 1,500/mm³
• Platelet count ≥ 100,000/mm³
• Bilirubin ≤ 1.7 mg/dL
• Albumin ≥ 2.8 mg/dL
• ALT ≤ 5.0 times upper limit of normal (ULN)
• Alkaline phosphatase ≤ 6 times ULN
• Prothrombin time ≤ 4 sec above ULN
• Creatinine ≤ 1.6 mg/dL
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients use effective contraception
• No Child's-Pugh's grading Class C hepatic impairment
• No history of allergic reaction attributed to compounds of similar chemical or biologic composition to PXD101

• No marked baseline prolongation of QT/QTc interval, including the following:

  • Repeated demonstration of a QTc interval > 500 msec
  • Long QT Syndrome
• No ongoing or active infection

• No significant cardiovascular disease, including any of the following:

  • Unstable angina pectoris
  • Uncontrolled hypertension
  • Congestive heart failure related to primary cardiac disease
  • Condition requiring anti-arrhythmic therapy
  • Ischemic or severe valvular heart disease
  • Myocardial infarction within the past 6 months
• No psychiatric illness or social situation that would preclude study compliance
• No other uncontrolled illness

PRIOR CONCURRENT THERAPY:

• More than 4 weeks since prior chemotherapy (6 weeks for nitrosureas or mitomycin C) and recovered
• More than 4 weeks since prior radiotherapy and recovered
• At least 2 weeks since prior valproic acid
• No concurrent combination antiretroviral therapy for HIV-positive patients
• No concurrent participation in another investigational study
• No other concurrent investigational agents
• No other concurrent anticancer therapy

• No concurrent use of any of the following:

  • Disopyramide
  • Dofetilide
  • Ibutilide
  • Procainamide
  • Quinidine
  • Sotalol
  • Bepridil
  • Amiodarone
  • Arsenic trioxide
  • Cisapride
  • Calcium channel blockers (e.g., lidoflazine)
  • Clarithromycin
  • Erythromycin
  • Halofantrine
  • Pentamidine
  • Sparfloxacin
  • Domperidone
  • Droperidol
  • Chlorpromazine
  • Haloperidol
  • Mesoridazine
  • Thiordazine
  • Pimozide
  • Methadone