Interleukin-12 and Trastuzumab in Treating Patients With Cancer That Has High Levels of HER2/Neu

Inclusion Criteria: * Patients must have a histologically proven Her2 overexpressing malignancy as determined by any standardized assay currently in clinical use * Patients must have measurable or evaluable disease * The patient must have failed standard curative and/or palliative therapies for their disease * Life expectancy of at least 6 months * No concurrent malignancy other than non-melanoma skin carcinoma * Adequate hematopoietic, cardiac, renal, and hepatic function * Calculated creatinine clearance will be used to assess renal function * Karnofsky Performance Status index \>= 70% * Women of childbearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control) prior to study entry and for the duration of study participation; a woman of childbearing potential is defined as a female who is biologically capable of becoming pregnant * Normal cardiac ejection fraction by echocardiogram or MUGA (i.e., greater than OSU lower limit of normal) * Written signed informed consent; the patient must be aware that his/her disease is neoplastic in nature and willingly consent after being informed of the procedure to be followed, the experimental nature of the therapy, alternatives, potential benefits, side-effects, risks, and discomforts Exclusion Criteria: * History of significant peripheral neuropathy or significant central nervous system disease * Brain or central nervous system metastasis at entry * Active or unstable cardiovascular disease or cardiac disease requiring drug or device intervention; history of coronary artery disease or congestive heart failure * Pregnant or nursing women * Surgery, radiotherapy, chemotherapy, or hormonal therapy during the three weeks prior to the initiation of therapy * Exposure to any investigational drug within three weeks prior to the start of dosing * Concurrent use of systemic corticosteroids * Known seropositive for hepatitis B surface antigen * Known seropositive for HIV antibody * Serious concurrent infection requiring intravenous antibiotic therapy * Clinically significant autoimmune disease (e.g., rheumatoid arthritis) * Clinically significant gastrointestinal bleeding or uncontrolled peptic ulcer disease * History of inflammatory bowel disease * Any other major illness which, in the investigator's judgment, will substantially increase the risk associated with the patient's participation in this study * Prior therapy with Herceptin