DISEASE CHARACTERISTICS:

• Histologically confirmed breast cancer

  • Must overexpress HER-2 gene

  • Metastatic or chest wall recurrent disease

    • Recurrent or progressive disease while receiving prior trastuzumab (Herceptin^®) (with or without chemotherapy) OR relapsed within 3 months of last dose of prior adjuvant trastuzumab for metastatic disease

• Measurable disease, defined as ≥ 1 unidimensionally measurable lesion > 20 mm by conventional techniques or > 10 mm by spiral CT scan

  • Site of measurable disease must not have been irradiated (except chest wall recurrence treated with adjuvant radiation therapy)

• No untreated brain metastases

  • Previously treated brain metastasis responsive to radiotherapy and/or surgery allowed provided the brain is not the sole site of measurable disease

• Hormone receptor status:

  • Not specified

PATIENT CHARACTERISTICS:

Sex

• Male or female

Menopausal status

• Not specified

Performance status

• ECOG 0-2

Life expectancy

• Not specified

Hematopoietic

• Absolute neutrophil count ≥ 1,500/mm^3
• Platelet count ≥ 100,000/mm^3
• Hemoglobin ≥ 9 g/dL

Hepatic

• AST and ALT ≤ 2 times upper limit of normal
• Bilirubin ≤ 1.5 mg/dL (3 mg/dL in the presence of Gilbert's disease provided direct bilirubin is normal)

Renal

• Creatinine ≤ 1.5 mg/dL

Cardiovascular

• LVEF normal by nuclear scan or echocardiogram
• No evidence of PR prolongation or AV block by EKG
• 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 active or ongoing infection
• No history of allergic reaction to compounds of similar chemical or biologic composition to vorinostat or other agents used in study
• No psychiatric illness or social situation that would preclude study compliance
• No other uncontrolled illness

PRIOR CONCURRENT THERAPY:

Biologic therapy

• See Disease Characteristics

Chemotherapy

• See Disease Characteristics
• More than 3 weeks since prior chemotherapy (6 weeks for nitrosoureas or mitomycin; 1 week for capecitabine) and recovered

Radiotherapy

• See Disease Characteristics
• More than 3 weeks since prior radiotherapy and recovered
• No concurrent radiotherapy for brain metastases

Surgery

• See Disease Characteristics

Other

• Recovered from prior therapy
• At least 2 weeks since prior valproic acid
• More than 4 weeks since prior investigational agents
• More than 4 weeks since prior lapatinib ditosylate
• No concurrent combination antiretroviral therapy for HIV-positive patients
• No other concurrent investigational agents
• Concurrent bisphosphonates allowed provided therapy was initiated prior to study treatment
• No other concurrent anticancer therapy