PART A (solid tumor patients): Patients receive decitabine IV over 1 hour on days 0-6 and doxorubicin IV over 15 minutes and cyclophosphamide IV over 1 hour on day 7. Patients then receive filgrastim (G-CSF) subcutaneously (SC) beginning on day 8 and continuing until blood counts recover OR pegfilgrastim SC once on day 8 or 9*. Treatment repeats every 28 days for up to 12 courses in the absence of disease progression or unacceptable toxicity.