Part I involves vaccine dose escalation in a population with no prior exposure to trastuzumab or other HER2-targeted therapies to determine if there is a significant, adverse safety signal regarding cardiac toxicity, in addition to preliminary assessment of the vaccine s immunogenicity and clinical activity. Five doses of 5, 10, 20 or 40 x 10(6) viable cells/AdHER2 DC vaccine will be given intradermally at Weeks 0, 4, 8, 16 and 24 in patients with metastatic solid tumors or high risk bladder cancer in the adjuvant setting characterized by some HER2/neu expression. Re-staging for clinical evidence of stable disease, partial response or better by immune-related response criteria will be assessed at Weeks 8, 16, 24, 36 and 48 with confirmatory scans (if indicated) at Weeks 12, 20, 28, 40 and 52. Adjuvant bladder cancer patients will undergo re-staging for evidence of disease recurrence (with confirmatory scans 4 weeks later if recurrence is documented) at Weeks 8, 16, 24, 36 and 48.