DISEASE CHARACTERISTICS:

• Histologically or cytologically confirmed hepatocellular carcinoma

• Not amenable to surgical resection

  • Tumor amenable to post-treatment biopsy

• Measurable disease

  • Patients with only lesions measuring > 1 cm to ≤ 2 cm must have all tumor assessments made by spiral CT scan

  • Indicator lesion(s) outside the area of prior treatment

    • If the sole indicator lesion is inside the prior treatment area, there must be clear evidence of disease progression associated with that lesion
  • Edges of the indicator lesion must be clearly distinct by CT scan
• Child-Pugh classification A or B
• No known CNS metastases

PATIENT CHARACTERISTICS:

Age

• 18 and over

Performance status

• ECOG 0-2

Life expectancy

• At least 24 weeks

Hematopoietic

• Absolute neutrophil count ≥ 1,500/mm^3
• Platelet count ≥ 75,000/mm^3

Hepatic

• Bilirubin ≤ 2 times upper limit of normal (ULN)
• AST and ALT ≤ 5 times ULN
• Albumin ≥ 2.5 g/dL
• PT/INR ≤ 1.5* NOTE: *INR range of 2-3 allowed for patients on full-dose anticoagulants provided the patient has been on a stable dose of warfarin or low molecular weight heparin for ≥ 2 weeks

Renal

• Creatinine ≤ 2 mg/dL

Cardiovascular

• No symptomatic congestive heart failure
• No unstable angina pectoris
• No cardiac arrhythmia

Other

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• No significant traumatic injury within the past 3 weeks
• No grade 1 or greater sensory peripheral neuropathy OR grade 1 with neuropathic pain of any etiology
• No prior allergic reaction attributed to compounds of similar chemical or biological composition to bortezomib
• No other malignancy within the past 3 years except adequately treated basal cell or squamous cell skin cancer
• No other concurrent uncontrolled illness
• No ongoing or active infection
• No psychiatric illness that would limit study compliance

PRIOR CONCURRENT THERAPY:

Biologic therapy

• More than 4 weeks since prior immunotherapy
• More than 4 weeks since prior biologic therapy
• No concurrent immunotherapy
• No concurrent colony-stimulating factors during the first course of study therapy

Chemotherapy

• More than 6 weeks since prior chemoembolization
• No prior systemic chemotherapy
• No concurrent chemotherapy

Endocrine therapy

• Not specified

Radiotherapy

• More than 4 weeks since prior radiotherapy
• More than 6 weeks since prior radiofrequency ablation
• No concurrent radiotherapy

Surgery

• More than 3 weeks since prior major surgery

Other

• More than 6 weeks since prior cryotherapy
• More than 6 weeks since prior ethanol injection
• More than 6 weeks since prior photodynamic therapy
• No prior systemic anticancer therapy
• No prior bortezomib
• No other concurrent investigational therapy
• No concurrent combination antiretroviral therapy for HIV-positive patients