1. Evidence of histologically or cytologically documented malignancy, including patients with treated, stable brain metastases. For Part A: Malignancy that is advanced and/or metastatic for which no proven therapy exists (for example, there is no comparable or satisfactory alternative drug or other therapy available to treat that stage of the disease). For Part B and C: Malignancy that is advanced and/or metastatic for which no proven therapy exists, and presents with disease that is amenable to serial measurement of pharmacodynamics by biopsy.