Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histologically or cytologically confirmed hepatocellular carcinoma

- Metastatic and/or unresectable disease

- Child-Pugh score A or B

PATIENT CHARACTERISTICS:

- ECOG performance status 0-2

- Neutrophil count > 1500/mm³

- Platelet count > 100,000/mm³

- Hemoglobin ≥ 9 g/dL

- AST and ALT ≤ 2.5 times upper limit of normal (ULN) (≤ 5.0 times ULN if elevation due
to disease involvement)

- Serum bilirubin ≤ 1.5 times ULN

- Serum creatinine ≤ 1.5 times ULN or creatinine clearance ≥ 50 mL/min

- Total serum calcium (corrected for serum albumin) or ionized calcium ≥ lower limit of
normal (LLN)

- Serum potassium ≥ LLN

- Serum sodium ≥ LLN

- Serum albumin ≥ LLN or 3 g/dL

- LVEF ≥ LLN as demonstrated by baseline MUGA or ECHO

- TSH and free T4 within normal limits (thyroid hormone replacement therapy allowed)

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective double-method contraception (one being a barrier
method) during and for 3 months after completion of study treatment

- INR < 1.5 or PT/PTT within normal limits

- No impaired cardiac function including any 1 of the following:

- QTc > 450 msec on screening ECG

- Congenital long QT syndrome

- History of sustained ventricular tachycardia

- History of ventricular fibrillation or torsades de pointes

- Bradycardia, defined as heart rate < 50 beats per minute

- Patients with a pacemaker and heart rate ≥ 50 beats per minute are eligible

- Myocardial infarction or unstable angina within the past 6 months

- Congestive heart failure (NYHA class III-IV)

- Right bundle branch block and left anterior hemiblock (bifascicular block)

- No uncontrolled hypertension

- No thrombolic or embolic events (e.g., cerebrovascular accident and transient
ischemic attacks) within the past 6 months

- No pulmonary hemorrhage/bleeding event > CTCAE Grade 2 within the past 4 weeks

- No other hemorrhage/bleeding event > CTCAE Grade 3 within the past 4 weeks

- No unresolved diarrhea > CTCAE grade 1

- No other concurrent severe and/or uncontrolled medical conditions

- No other primary malignancy within the past 5 years except curatively treated
carcinoma in situ of the cervix or basal cell or squamous cell carcinoma of the skin

- No serious non-healing wound, ulcer, or bone fracture

- No evidence or history of bleeding diathesis or coagulopathy

- No significant traumatic injury within the past 4 weeks

- No known or suspected allergy to sorafenib tosylate or any other study drug

- No condition that would impair a patient's ability to swallow whole pills

- No malabsorption problem

- No known human immunodeficiency virus (HIV) or hepatitis C positivity (baseline
testing for HIV and hepatitis C is not required)

- No significant history of non-compliance to medical regimens

PRIOR CONCURRENT THERAPY:

- No prior HDAC inhibitors, DAC inhibitors, HSP90 inhibitors, sorafenib tosylate, or
valproic acid for the treatment of cancer

- More than 4 weeks since prior chemotherapy, investigational drugs, or major surgery
and recovered

- More than 4 weeks since open biopsy

- More than 5 days since prior and no concurrent valproic acid for any medical
condition

- No concurrent St. John's wort or rifampin

- No concurrent drugs with a risk of causing torsades de pointes

- No concurrent CYP3A4 inhibitors

- No concurrent radiotherapy

- No concurrent grapefruit, grapefruit juice, or Seville (sour) oranges

- No other concurrent investigational therapy

- No other concurrent anticancer agents

- Concurrent anticoagulation treatment with warfarin or heparin allowed