DISEASE CHARACTERISTICS:

• Histologically confirmed adenocarcinoma of the prostate

• Relapsed disease after definitive local therapy, as documented only by a rise in prostate-specific antigen (PSA)

  • Experienced PSA relapse after definitive local therapy

  • Rising PSA (≥ 1.0 ng/mL after nadir < 1.0 ng/mL)

    • PSA increase of ≥ 0.3 ng/mL (increase occurred between 2 separate measurements taken ≥ 4 weeks apart)
  • The first of these two PSA values must rise above a previously recorded post-therapy nadir value
• Ineligible for curative therapy
• No clinical evidence of local recurrence (i.e., palpable induration or mass in the prostatic fossa) other than PSA elevation
• No evidence of palpable disease in the prostatic bed

• No metastatic disease (M0)

  • No non-nodal (> N1) metastasis
  • No evidence of osseous metastasis on bone scan within the past 28 days

PATIENT CHARACTERISTICS:

Age

• Over 18

Performance status

• ECOG 0-1

Life expectancy

• At least 1 year

Hematopoietic

• Platelet count ≥ 30,000/mm^3
• Absolute neutrophil count ≥ 1,000/mm^3

Hepatic

• No known hepatitis B or C positivity

Renal

• Creatinine clearance ≥ 30 mL/min

Immunologic

• No known human T-cell lymphotropic virus positivity
• No hypersensitivity to bortezomib, boron, or mannitol
• No known HIV 1 or 2 positivity
• No active, ongoing bacterial, viral, or fungal infection

Other

• Fertile patients must use effective contraception
• No peripheral neuropathy ≥ grade 2
• No other disease, condition, or social or geographic constraint that would preclude study participation
• No other malignancy within the past 5 years except basal cell or squamous cell skin cancer

PRIOR CONCURRENT THERAPY:

Biologic therapy

• Not specified

Chemotherapy

• No concurrent chemotherapy

Endocrine therapy

• See Disease Characteristics
• At least 6 months since prior hormonal therapy combined with radiation therapy as definitive therapy
• Neoadjuvant hormonal therapy prior to definitive therapy (e.g., surgery, radiation therapy, brachytherapy, or cryoablation) allowed
• No other concurrent hormonal therapy

Radiotherapy

• See Disease Characteristics
• More than 12 months since prior radioactive seed therapy
• No concurrent radiotherapy

Surgery

• See Disease Characteristics
• More than 4 weeks since prior surgery
• No concurrent surgery

Other

• No concurrent second-line herbal preparations, including PC-SPES
• No other concurrent investigational agents